um medical center university campus lake avenue …

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UMASS MEMORIAL MEDICAL CENTER

UNIVERSITY CAMPUS 55 LAKE AVENUE NORTH

WORCESTER, MA

PREPARED FOR

DCAMM

Prepared by

B2Q Associates, Inc.

North Andover, MA

Revision Date

5/26/2015

2 DCAMM UMMC Worcester, MA | AL2 Energy Audit

B2Q Associates, Inc. 100 Burtt Rd. Suite 212 Andover, MA 01810

ASHRAE LEVEL 2 ENERGY AUDIT UMASS MEMORIAL MEDICAL CENTER - UNIVERSITY CAMPUS

Introduction .................................................................................................................................... 6

Contacts .......................................................................................................................................... 8

Approach & Modeling Methodology .............................................................................................. 9

Cost Estimate Methodology ......................................................................................................... 10

Executive Summary Table ............................................................................................................. 11

ACC Building Executive Summary Table ....................................................................................... 13

Facility Description ........................................................................................................................ 14

Baseline Energy Use & Benchmarking .......................................................................................... 15

Energy Use Graphs .................................................................................................................... 15

Benchmarking ........................................................................................................................... 21

eQuest Model Calibration ............................................................................................................. 23

Energy Conservation Measures .................................................................................................... 27

ECM-01.01 (a) Lighting Retrofit ................................................................................................ 28

ECM-04.09 (a)-1 Tighten Occupancy Schedules ....................................................................... 31

ECM-04.09 (a)-2 Install New Occupancy Sensors for HVAC Control ........................................ 34

ECM-09.00 (a) Retrofit AHU-5 Supply Fan with VFD ................................................................ 37

ECM-18.00 (a)-1 Replace Weather Station ............................................................................... 40

ECM-18.00 (a)-2 Calibrate Flow Stations & Reduce Unoccupied Outdoor Air ......................... 44

ECM-18.00 (a)-3 Static Pressure Reset on AHUs 1-4 ................................................................ 47

ECM-18.00 (a)-4 Reprogram Discharge Temperature Reset on AHUs 1-4 ............................... 51

ECM-18.00 (a)-5 Reduce AHU-2 OA Damper Minimum Position ............................................. 55

ECM-18.00 (a)-6 Calibrate Zone CO2 Sensors .......................................................................... 58

ECM-18.00 (a)-7 Replace AHU-4 Return Air CO2 Sensor .......................................................... 61

ECM-18.00 (a)-8 Reduce VAV Unoccupied Flow Set-points ..................................................... 65

ECM-18.00 (a)-9 Reprogram Zone Set-points & Implement Dead-band ................................. 68

ECM-18.00 (a)-10 Reconfigure Unoccupied Zone Temperature Control ................................. 72

Benedict Executive Summary Table .............................................................................................. 76

Facility Description ........................................................................................................................ 77

Baseline Energy Use & Benchmarking .......................................................................................... 78

Energy Use Graphs .................................................................................................................... 78

Benchmarking ........................................................................................................................... 84

eQuest Model Calibration ............................................................................................................. 86

Energy Conservation Measures .................................................................................................... 91

ECM-01.01 (b) Lighting Retrofit ................................................................................................ 92

ECM-02.01 (b) Install Occupancy Sensors ................................................................................ 95


ECM-04.09 (b)-1 Fan Coil Unit Controls Upgrade ..................................................................... 98

ECM-04.09 (b)-1A Unoccupied Temperature Set-backs ........................................................... 98

ECM-04.09 (b)-1B Close FCU OA Dampers During Unoccupied Periods ................................ 100

ECM-04.09 (b)-1C Retrofit FCU Fans with EC motors ............................................................. 101

ECM-04.09 (b)-1 Cost Estimate ............................................................................................... 104

ECM-04.09 (b)-2 HW Loop Differential Pressure Reset .......................................................... 105

ECM-12.04 (b) Install Low-E Window Film.............................................................................. 108

Hospital Executive Summary Table ............................................................................................. 110

Facility Description ...................................................................................................................... 111

Baseline Energy Use & Benchmarking ........................................................................................ 112

Energy Use Graphs .................................................................................................................. 112

Benchmarking ......................................................................................................................... 118

eQuest Model Calibration ........................................................................................................... 120

Energy Conservation Measures .................................................................................................. 124

ECM-01.01 (c) Lighting Retrofit............................................................................................... 125

ECM-04.02 (c) Comparative Enthalpy Economizer on AHU-1L,1R,1T-7T ............................... 129

ECM-04.09 (c)-1 Reconfigure Preheat Circulator Enable Sequence ....................................... 132

ECM-04.09 (c)-2 Reconfigure AHU-15T/16T Preheat Temperature Control .......................... 136

ECM-04.09 (c)-3 Increase AHU-10T & 11T Minimum Discharge Set-point ............................ 140

ECM-04.09 (c)-4 Hot Water Loop Differential Pressure Reset Schedule ................................ 143

ECM-04.11 (c) Reconfigure Preheat & Discharge Air Reset Schedules on AHU-1B-6B .......... 147

ECM-04.14 (c) Kitchen Hood Controls .................................................................................... 151

ECM-17.03 (c)-1 Complete VAV Conversion AHU-1B-6B, 1T,2T,3T,4T,6T,7T ......................... 154

ECM-17.03 (c)-2 Retrofit Fans with VFDs / Install Branch Duct Dampers .............................. 158

ECM-17.03 (c)-3 Retrofit Fans with VFDs / Reset Speed Based on OAT ................................. 163

ECM-18.00 (c)-1 Replace Preheat Valves & Actuators ........................................................... 167

ECM-18.00 (c)-2 Lock-Out Humidification & Calibrate Humidity Sensors .............................. 171

ECM-18.00 (c)-3 Replace Leaking Preheat Valve on AHU-13T ............................................... 175

ECM-18.00 (c)-4 Duct Static Pressure Reset on AHU-1R, 15T/16T ......................................... 179

ECM-18.00 (c)-5 Adjust AHU-1L Temperature Control ........................................................... 181

ECM-18.00 (c)-6 Optimize Heat Exchanger Reset Schedule ................................................... 185

ECM-18.00 (c)-7 Replace Leaking Chilled Water Valve on AHU-11T ...................................... 188

ECM-18.00 (c)-8 Fix Mixed Air Damper Issues to Improve Economizer ................................. 193

ECM-21.02 (c) Hospital Solar Hot Water ................................................................................ 197

Other Opportunities Reviewed ............................................................................................... 198

Lakeside Executive Summary Table ............................................................................................ 200




Benchmarking ......................................................................................................................... 208



ECM-01.01 (d) Lighting Retrofit .............................................................................................. 216

ECM-04.09 (d) Modify Mixed Air Temperature Control on AHU 1-10 ................................... 219


ECM-04.13 (d) Install Occupancy Sensors in Operating Rooms ............................................. 222

ECM-18.00 (d)-1 Discharge Air Temperature Reset on AHU 1-10 .......................................... 225

ECM-18.00 (d)-2 Static Pressure Reset on AHU 1-8................................................................ 229

ECM-18.00 (d)-3 Reconfigure Preheat Circulator Control ...................................................... 232

ECM-18.00 (d)-4 Optimize Hot Water Supply Temperature Reset ........................................ 235

ECM-18.00 (d)-5 Replace AHU-4 Return Temperature Sensor ............................................... 238

ECM-18.00 (d)-6 Replace Leaking CHW valve on AHU-2 ........................................................ 242

Lazare Research Building (LRB) Executive Summary Table ........................................................ 246


Laboratories ............................................................................................................................ 248

Vivarium (Animal Rooms) ....................................................................................................... 248

Office & Support Areas ........................................................................................................... 249



Benchmarking ......................................................................................................................... 256



ECM-01.01 (e) : Lighting Retrofit ............................................................................................ 265

ECM-03.00 (e) Replace Cage Washer Pump Motors .............................................................. 269

ECM-03.01 (e)-1 EC Motors on Bio-Safety Cabinet Fans ........................................................ 271

ECM-03.01 (e)-2 EC Motors on DHW & Non-Potable Water Circulators ............................... 273

ECM-03.01 (e)-3 EC Motors on AHU-10, 11 Supply Fans........................................................ 276

ECM-03.01 (e)-4 Retrofit RO Water Pumps with VFDs ........................................................... 280

ECM-04.02 (e) Comparative Enthalpy Economizer on AHU-9 ................................................ 283

ECM-04.09 (e)-1: Scheduling and Set-points on AHU-9 Zones ............................................... 287

ECM-04.09 (e)-2 Reprogram AHU-7 Preheat Control Sequence ............................................ 291

ECM-04.09 (e)-3 Reduce Air Change Rates in Labs ................................................................. 295

ECM-04.09 (e)-4 Hot Water Loop Differential Pressure Reset ............................................... 298

ECM-04.09 (e)-5 Process CHW Loop Differential Pressure Reset ........................................... 301

ECM-04.11 (e)-1 Heat Recovery on Make-up Air Units (AHU 1-6) ......................................... 305

ECM-04.11 (e)-2 Install Passive Chilled Beams in Labs ........................................................... 313

ECM-18.00 (e)-1 Static Pressure Reset ................................................................................... 318

ECM-18.00 (e)-2 Discharge Air Temperature Reset ................................................................ 322

ECM-18.00 (e)-3 Replace Leaking Preheat Valves .................................................................. 326

ECM-18.00 (e)-4 Replace Leaking Chilled Water Valve .......................................................... 330

ECM-18.00 (e)-5 Reduce AHU-9 Minimum Outdoor Air ......................................................... 334

ECM-18.00 (e)-6 Reprogram AHU-10, 11 Zone Temperature Set-points ............................... 338

ECM-18.00 (e)-7 Replace Preheat Face/Bypass Damper Actuators ....................................... 342

ECM-18.00 (e)-8 Exhaust Fan Static Pressure Reset ............................................................... 347

ECM-18.00 (e)-9 Temperature Setbacks in Lab Corridors ...................................................... 351

ECM-18.00 (e)-10 Hot Water Supply Temperature Reset ...................................................... 354

Other Opportunities Reviewed ............................................................................................... 358

Medical School Executive Summary Table ................................................................................. 359





Benchmarking ......................................................................................................................... 368



ECM 1.01 (f) Lighting Retrofit ................................................................................................. 376

ECM 3.01 (f)-1 Retrofit FCU & FPB Fans with EC motors ........................................................ 379

ECM 3.01 (f)-2 Retrofit Environmental Room Evaporator Fans with EC Motors ................... 382

ECM 4.07 (f) Upgrade Terminal VAV Mixing Box Controls ..................................................... 384

ECM 9.00 (f)-1 Loading Dock Variable Exhaust Controls ........................................................ 387

ECM 9.00 (f)-2 Reduce Lab Air Changes.................................................................................. 391

ECM 9.00 (f)-3 Install VFDs & CO2 Ventilation Controls on Library AC Units ......................... 394

ECM 17.09 (f) Reclaim Return Air on AC-12 ........................................................................... 400

ECM 18.00 (f)-1 Optimize Perimeter HW Reset ..................................................................... 402

ECM 18.00 (f)-2 Auditorium Scheduling & Occupancy Controls ............................................ 406

ECM 18.00 (f)-3 Replace Heating Valves & Actuators ............................................................ 410

ECM 18.00 (f)-4 Replace Cooling Valves & Actuators ............................................................. 415

ECM 18.00 (f)-5 Repair Economizer Dampers & Optimize Sequence .................................... 419

ECM 18.00 (f)-6 Air-Sealing Repairs on AC Units .................................................................... 424

ECM 18.00 (f)-7 Optimize Static Pressure Reset ..................................................................... 428

ECM-21.02 (f) School Solar Hot Water ................................................................................... 432

Central Plant CHW Pumping Executive Summary ...................................................................... 433

Facility Description .................................................................................................................. 434

Central Plant Load Calibration ................................................................................................ 439

ECM 4.03-1 – Conversion from Constant Volume Primary to Variable Primary Pumping ..... 441

ECM 4.13-1– Coordinated Control of the CHP Primary and Building Tertiary pumping ........ 444

Solar Photovoltaic Executive Summary ...................................................................................... 447

ECM 21-01 (g)-1 Sherman Center Rooftop Photovoltaic Array .............................................. 448

ECM 21-01 (g)-2 Quad Four Dual-Axis Tracker Photovoltaic Array ........................................ 449

ECM 21-01 (g)-3 Plantation Hillside Fixed Tilt Photovoltaic Array ......................................... 450

ECM 21-01 (g)-4 South Road Garage Canopy Photovoltaic Array .......................................... 451

ECM 21-01 (g)-5 Plantation Street Garage Canopy Photovoltaic Array ................................. 452

ECM 21-01 (g)-6 First Road Garage Canopy Photovoltaic Array ............................................ 453

Additional ECM Summary Tables ...................................................... Error! Bookmark not defined. ECMs By Building & Measure Category .................................................................................. 454

ECMs By Building & Grouped Implementation Costs ............................................................. 455

ECMs By Measure Category .................................................................................................... 456

Solar Hot Water Report .............................................................................................................. 457

Renewable Energy Technology Report ....................................................................................... 458


INTRODUCTION

This focused ASHRAE Level 2 audit was conducted by B2Q Associates, Inc. in collaboration with the Massachusetts Department of Capital Asset Management and Maintenance (DCAMM) and the University of Massachusetts Medical Center (UMass). This study is part of DCAMM’s Accelerated Energy Program (AEP), whose focus is to assess the feasibility of a “deep energy retrofit” which includes a goal to reduce purchased energy by 20%-30% and then identify renewable energy systems where financially and technically feasible. The intent is to identify and implement and integrated package of energy efficiency measures and renewable energy systems that will maximize net present value of the building over 10-20 years.

The intent of this report is to present the results associated with Task 1 of the AEP process, which includes an ASHRAE Level 2 audit of all buildings, existing condition assessment, utility analysis, preliminary list of energy conservation measures (ECMs), and a renewable energy and innovative technology assessment.

The buildings included this report are: Ambulatory Care Center (ACC), Benedict Building, Hospital, Lakeside, Lazare Research Building (LRB), and Medical School.

B2Q worked with UMass Medical Facilities and Maintenance staff from June 2014 through the writing of this report in support of the following efforts:

1. Obtain historical energy consumption records in order to establish a baseline for each building, as well as benchmark the facilities’ normalized energy consumption against each other and against other available benchmarking data sets.

2. Gather available documentation for each building including: mechanical and architectural drawings, Testing, Adjusting, and Balancing (TAB) reports, space utilization (occupancy) plans, control sequences of operation, as well as previous technical assistance and scoping studies. Documentation was processed and analyzed to create tables of equipment parameters that were used to establish accurate baseline energy models for each building as well as to be used in developing Opinions of Probable Construction Costs for the ECM’s identified.

3. Walk through mechanical spaces and occupied areas, interview facilities staff, and review building automation system (BAS) controls to gain an understanding of each building’s equipment and document operational strategies.

4. Review lighting reflected ceiling plans as well as past lighting audits and walk through a statistical sample of the occupied areas to gain an understanding of each building’s lighting systems and fixture counts to develop a high level list of recommended lighting upgrades.

5. Review available historical trend data for major air- and water-side equipment in each building to compare documented control sequences to observed operation and identify issues and potential improvement opportunities. In order to accomplish this review of large quantities of data we used a powerful visualization/analytic software tool called


CSense which is part of General Electric’s Proficy suite of industrial hardware and software.

6. Modify the existing eQuest models for each building to accurately reflect the baseline conditions documented during the information gathering effort.

7. Identify energy conservation measures for each building; define the necessary eQuest parametric runs and develop spreadsheet models to estimate energy savings for each ECM.

8. Develop budgetary Opinions of Probable Construction Costs for the ECM’s identified and calculate simple payback estimates. These estimates presented in the draft report do not include the cost reduction impact of potential utility incentives. These will be accounted for in the final report after utility review.


CONTACTS

UMASS MEDICAL Mark Armington Director Facilities (508) 856-5202 [email protected]

David Macneil Sr. Mechanical Project Manager

(508) 856-4776 [email protected]

Jim Gardner Director of Facilities Maintenance


Joseph Collins Director of Energy Resources


Andrew Doe Mechanical Engineer (508) 856-2498 [email protected]

Matthew Stelmach Sr. Electrical Project Manager


Glenn Myers Maintenance Manager


Steven Blair Assistant Director, Power Plant


Todd Manning Senior Construction Manager


DCAMM

Tony Ransom Program Manager (617) 727-4030 x31561

[email protected]

John Crisley Project Manager (617) 727-4030 x31561

[email protected]

Ray Soohoo Energy Planner (617) 727-4030 x31509

[email protected]

B2Q ASSOCIATES Paul Banks Principal (978) 447-5601 [email protected]

Richard Andelman Vice President (978) 447-5603 [email protected]

Michael Margareci Vice President (978) 447-5602 [email protected]

Kevin Keena Sr. Project Manager (978) 447-5603 [email protected]

Joshua Doolittle Engineer (978) 447-5607 [email protected]

Sam Deptula Engineer (978) 447-5611 [email protected]

Janne Kairento Engineer (978) 447-5610 [email protected]

Patrick Colby Designer (978) 447-5615 [email protected]

Mark Penta Lighting Specialist (978) 447-5602 [email protected]


APPROACH & MODELING METHODOLOGY

A prior computer model of each building on campus was developed by Andelman & Lelek and used to analyze the energy savings from applicable EEMs using the eQuest building analysis program. eQuest uses the latest DOE-2.2 building energy analysis software as its calculating engine and this model was customized to the observed operation of HVAC equipment in each building on campus. eQuest also allows for the interactive effects between EEMs to be modeled. For EEMs which were deemed to be too difficult and impractical to be modeled in eQuest, custom spreadsheet calculations were performed by B2Q. The Energy savings Methodology sections of each EEM describe whether a measure was modeled using a spreadsheet or eQuest.

The A&L eQuest model was created using information collected over the course of several site visits, through discussions with facilities staff, equipment submittals, nameplate and physical operating information, building plans, and reviewing existing building automation systems. Worcester, MA TMY3 weather data was used in the analysis. Electric utility cost and cost savings were calculated using the utility rates estimated by B2Q of $0.10/kWh of electricity ($0.12/kWh for ACC only), $0.12/ton-hour of chilled water use, and $10.00/MLb of steam. Existing zoning & equipment information in the A&L model was compared against observations made on site, with necessary adjustments being made to the model baseline. The charts in Appendix B: “eQuest vs. Design Input Sheets” give an overview of the changes made to the baseline model during this process. For each EEM to be modeled in eQuest, parametric runs were created and then compared against the baseline model to calculate energy savings.

Assumptions were made for some inputs to the eQuest models due to the limitations in the availability of design data and as-built documentation. These assumptions were as follows:

“Auto-sizing” was allowed only for design parameters that could not be determined based on nameplate data, mechanical drawings, TAB reports, etc.

Savings for each individual ECM were analyzed against either the baseline model or another parametric run to capture measure interactive effects, where applicable.


COST ESTIMATE METHODOLOGY

In order to provide more accurate opinions of probable construction cost for each of the ECMs described below, wherever possible B2Q utilized vendor quotes and/or estimates, including costs from past similar projects. Where this information was unavailable, B2Q utilized industry-standard cost estimating resources like RS Means. All VFD costs from the measures above are based on 18-pulse drives and are assumed to require a motor replacement in order to be compatible with the VFD. For component replacements, such as valves or dampers, B2Q included the cost to reconnect the control point as DDC with new electric actuators. New DDC point costs were standardized at $1,500 per point. A prevailing wage labor rate of $150 per hour was used for all trades. For all measures, line item costs for creating as-builts and contractor commissioning were also included so that UMass Medical Center staff could have accurate and comprehensive records of all work completed. Contingency, project management, engineering, and commissioning costs were estimated as a percentage of the project cost subtotal and these percentages were standardized as shown in the table below, with the exception of reduced engineering and contingency for capital measures with significant cost and increased commissioning for lower cost controls improvements.

Table 1: Summary of standard contingency, project management, engineering, and commissioning mark-ups

Contingency 20%

Engineering 10%

Construction Administration 5%

Commissioning 5%

Construction Observation 10%

Project Closeout & Expenses 5%


EXECUTIVE SUMMARY TABLE

The table below summarizes estimated energy savings, project costs, and simple payback periods for each of the six (6) buildings included in this study, in addition to the central chilled water pumping analysis and renewables.

Building

Equivalent Electricity Savings5

Equivalent Natural Gas

Savings5

Total Cost

Savings1

Estimated Retrofit

Cost

Payback Before

Incentive

Estimated Potential Electric

Incentive3

Estimated Potential

Gas Incentive3

Estimated Retrofit

Cost After Incentives

Estimated Payback

After Incentives

- kWh therms $ $ yrs $ $ $ yrs

Ambulatory Care Center (ACC) 850,478 161,467 $268,471 $1,502,308 5.6 $255,144 $201,834 $1,045,330 3.9

Benedict 456,057 37,133 $79,060 $1,124,750 14.2 $136,817 $46,417 $941,516 11.9

Hospital 7,164,528 763,680 $1,565,077 $8,694,405 5.6 $2,149,358 $954,601 $5,590,446 3.6

Lakeside6 675,129 260,440 $347,882 $390,915 1.1 $133,952 $256,963 $0 0.0

Lazare Research Building (LRB) 2,884,273 580,299 $858,530 $4,372,635 5.1 $865,282 $725,373 $2,781,979 3.2

Medical School 4,588,945 356,988 $854,250 $5,829,019 6.8 $1,376,684 $446,235 $4,006,100 4.7

Central Plant CHW Pumping 526,782 0 $52,678 $208,575 4.0 $158,035 $0 $50,540 1.0

Solar Photovoltaic2,4 3,656,978 0 $365,698 $16,369,277 44.8 $1,097,093 $0 $15,272,184 41.8

TOTALS 20,803,171 2,160,007 $4,391,646 $38,491,883 8.8 $6,240,951 $2,700,009 $29,550,923 6.7

Notes: (1) The cost savings figures in the summary table above assume the following utility rates: $0.10/kWh, $0.12/ton-hour, $10.00/Mlb. (2) Potential grants are not included in the project economics shown in the table above. (3) Incentives shown in the table are based on incentive rates provided by National Grid and NSTAR for DCAMM’s AEP projects of $0.30/kWh saved and $1.25/therm saved, respectively. All incentives presented in this report are subject to the respective utility’s review and approval. (4) Solar PV Renewables are not eligible for electric utility incentives and are therefore excluded from the preliminary incentive estimate in the table. (5) The Equivalent Electricity Savings and Equivalent Natural Gas Savings are calculated to include the CHW and Steam savings based on a ratio of the central CHW plant fuel source and plant efficiencies. (6) Potential electric and gas incentives at Lakeside were each reduced by $68,586.50 to limit the payback after incentives for this building to 0 years. However, column total incentives are based on the sum of costs and equivalent electricity and gas savings for all buildings and therefore have not been discounted.

Also note that energy savings, implementation costs, and utility incentives for Solar Hot Water measures associated with the Hospital and School are included in totals for those buildings shown in the table above.


The table below summarizes the same information presented in the table on the previous page; however, electricity (kWh), chilled water (ton-hours), and steam (Mlbs) energy savings have been listed out separately to provide additional granularity. Refer to the building-level executive summary tables and measure descriptions throughout the report for the energy savings and project economics associated with each energy conservation measure identified.

Building

Electric Energy Savings

CHW Energy Savings

Steam Energy Savings

Equivalent Electricity

Savings

Equivalent Natural Gas

Savings

Total Cost

Savings

Estimated Retrofit

Cost

Payback Before

Incentive

- kWh ton-hr Mlb kWh therms $ $ yrs

Ambulatory Care Center (ACC) 652,272 609,866 11,701 850,478 161,467 $268,471 $1,502,308 5.6

Benedict 442,807 40,771 2,989 456,057 37,133 $79,060 $1,124,750 14.2

Hospital 5,985,524 3,627,705 53,120 7,164,528 763,680 $1,565,077 $8,694,405 5.6

Lakeside 324,067 1,080,190 18,585 675,129 260,440 $347,882 $390,915 1.1

Lazare Research Building (LRB) 2,410,232 1,458,588 44,248 2,884,273 580,299 $858,530 $4,372,635 5.1

Medical School 4,045,373 1,672,529 24,901 4,588,945 356,988 $854,250 $5,829,019 6.8

Central Plant CHW Pumping 526,782 0 0 526,782 0 $52,678 $208,575 4.0

Renewables 3,656,978 0 0 3,656,978 0 $365,698 $16,369,277 44.8

TOTALS 18,044,035 8,489,650 155,544 20,803,171 2,160,007 $4,391,646 $38,491,883 8.8

Note: The table above uses the same assumptions for utility rates: $0.10/kWh, $0.12/ton-hour, $10.00/Mlb.

Refer to the Section titled “Error! Reference source not found.” on Page Error! Bookmark not defined. for summary tables with line items for all measures included in this report formatted in three different forms: 1) ECMs by Building and Measure Category, 2) ECMs by Building, and 3) ECMs by Measure Category

13 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Ambulatory Care Center

ACC BUILDING EXECUTIVE SUMMARY TABLE

Notes: The cost savings figures in the summary table above assume the following utility rates: $0.10/kWh, $0.12/ton-hour, $10.00/Mlb.

ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total

Cost

Savings

Retrofit

Cost

Payback

Before

Incentive

- - kWh ton-hr Mlb $ $ yrs

01.01 (a) Lighting Retrofit 83,832 0 0 $10,060 $116,710 13.9

04.09 (a)-1 Tighten Occupancy Schedules 40,288 35,207 1,605 $25,106 $30,625 1.2

04.09 (a)-2 Install New Occupancy Sensors for HVAC Control 95,875 30,917 1,276 $27,976 $708,110 25.3

09.00 (a) Retrofit AHU-5 Supply Fan with VFD 8,648 0 0 $1,038 $23,000 22.2

18.00 (a)-1 Replace Weather Station 251 39,269 -23 $4,516 $12,700 2.8

18.00 (a)-2 Calibrate Flow Stations & Reduce Unoccupied OA -3,015 63,186 2,039 $27,614 $35,100 1.3

18.00 (a)-3 Static Pressure Reset on AHUs 1-4 162,714 27,859 -182 $21,046 $38,200 1.8

18.00 (a)-4 Reprogram Discharge Temperature Reset on AHUs 1-4 -3,020 73,412 280 11,250 $20,300 1.8

18.00 (a)-5 Reduce AHU-2 OA Damper Minimum Position -236 5,654 320 $3,852 $7,700 2.0

18.00 (a)-6 Calibrate Zone CO2 Sensors 0 19,892 0 $2,387 $52,200 21.9

18.00 (a)-7 Replace AHU-4 Return Air CO2 Sensor 0 6,703 0 $804 $3,500 4.4

18.00 (a)-8 Reduce VAV Unoccupied Flow Set-points -4,505 183,954 2,429 $45,827 $389,900 8.5

18.00 (a)-9 Reprogram Zone Set-points & Implement Deadband 271,440 123,813 3,595 $83,380 $55,650 0.7

18.00 (a)-10 Reprogram Unoccupied Zone Temperature Control 0 0 361 $3,615 $8,613 2.4

652,272 609,866 11,701 268,471 1,502,308 5.6TOTALS


FACILITY DESCRIPTION

The Ambulatory Care Center (ACC) is a seven story, 258,000 ft2 building that houses a mix of ambulatory clinical care centers, as well as several clinical and translational research programs. The building was opened in 2010 and achieved LEED Silver certification in 2011. The ACC attaches directly to the South Road Patient and Visitor Parking Garage and is directly accessible from three floors. The building is designed to accommodate 183,000 patient visits a year with several floors devoted to exam and treatment rooms. The facility does not have a kitchen or large cafeteria, except for a small café that sells to-go food and beverage items.

Steam and chilled water (CHW) are supplied to the building by the central power plant. There is one set of (3) tertiary CHW pumps that are designed to maintain a CHW loop differential pressure set-point in the building; however it was observed that the pumps do not normally run. The ACC Building receives steam at approximately 50 psig from the central plant.

There are (2) steam to hot water (HW) heat exchangers (HXs) that serve AHUs, fan coil units, VAV boxes, fan powered boxes, and perimeter baseboard. The pair of HXs has one set of (2) pumps that operate lead/lag to circulate the HW throughout the building. Both the HW pumps and the tertiary CHW pumps are equipped with VFDs. Domestic HW is provided by (2) steam to DHW HXs, each with 225 gallons of storage capacity.

There are (7) major air handling units in the building. Of these AHUs, (4) serve occupied areas in the building. These AHUs are all mixed air variable volume with comparative enthalpy economizer strategies, and have hot water (HW) preheat coils & chilled water (CHW) cooling coils. These AHUs all have a design supply airflow capacity of 65,000 cfm and serve both constant volume (CV) and variable volume (VAV) boxes with HW reheat coils. The remaining (2) AHUs are 100% recirculation units that condition electrical substation rooms. These units are CV, have design airflow capacities of 5,000 cfm or less, and feature cooling coils only. The building’s 6th floor pharmacy is served by AHU-7, which is a HEPA filtration unit equipped with a variable speed booster fan. Preconditioned air is supplied to AHU-7 from AHU-1,2,3, and 4, so this unit does not include heating or cooling coils.

There are also (4) fan coil units (FCUs) that serve mechanical and storage spaces and (2) computer room air conditioner (CRAC) units.

There are approximately (8) building exhaust fans serving toilet and general areas, and (5) smoke control pressurization fans serving stairwells and elevator shafts that are normally off.

ACC Building HVAC control is fully DDC through the Siemens building automation system (BAS). Some advanced control strategies such as comparative enthalpy economizer, demand-based discharge temperature reset, demand-controlled ventilation, and hot water reset are already implemented on equipment throughout the building.

A description of the existing lighting systems in the building can be found in the base case description of ECM-8: Lighting Retrofit.


BASELINE ENERGY USE & BENCHMARKING

ENERGY USE GRAPHS

ELECTRICITY Figure 1 on the following page shows electricity use for the ACC Building for Fiscal Years 2011 – 2014. It can be seen that electricity use is fairly consistent throughout the year, with slight variations between the years likely due to weather effects. According to facilities staff, a LED lighting retrofit was completed in the South Parking Garage in November 2011, which is attached to the ACC Building and is included in its utility meter. The project involved replacing metal halide fixtures with LED fixtures and resulted in an estimated 60,000 kWh in monthly electricity savings. It is not clear why the savings associated with this retrofit are not reflected in the monthly data obtained from power plant records following installation.

In November 2013, a clear drop of approximately 90,000 kWh in monthly electricity consumption is shown in the chart. The source data obtained from power plant records was reviewed to verify that this was not associated with the lighting project described above. According to facilities staff, this reduction may have been the result of changes made to equipment schedules and/or set-points; however this could not be confirmed.

Figure 2 on the following page shows the utility use baseline for energy model calibrations. This baseline was determined by taking the average of the FY11-13 data and subtracting the expected electricity savings from the lighting retrofit described above (approximately 60,000 kWh/month). The chart shows that the resulting baseline average is nearly in line with the available data from Fiscal Year 2014, which was excluded from baseline calculations because the dataset was incomplete.


Figure 1: ACC monthly electricity use (kWh) for Fiscal Years 2011 - 2014.

Figure 2: ACC baseline electricity use (kWh) profile, using averaged monthly data from Fiscal Years 2011 - 2013 that has been corrected to reflect the savings associated with the lighting retrofit in the adjacent parking garage.

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STEAM This chart shows the monthly steam consumption for Fiscal Years 2011 – 2014. In Fiscal Years 2012 – 2014, some pronounced variations can be seen between months, possibly due to differentials in meter read dates. It can also be seen that Fiscal Year 2014 has a noticeably higher consumption during the winter months. The bottom graph shows the steam use averaged over Fiscal Years 2011 – 2013, taken as the utility use baseline for energy model calibrations. Fiscal Year 2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 3: ACC monthly steam energy use (Lbs) for Fiscal Years 2011 - 2014.

Figure 4: ACC baseline steam energy use (Lbs) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

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CHILLED WATER The chart below shows the ACC Building CHW use from Fiscal Years 2011 – 2014.It can be seen that CHW use is failr consistent from year to year, with slight variations between the years likely due to weather effects. The bottom graph shows the CHW use averaged over Fiscal Years 2011 – 2013, taken as the utility use baseline for energy model calibrations. Fiscal Year 2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 5: ACC monthly chilled water energy use (ton-days) for Fiscal Years 2011 - 2014.

Figure 6: ACC baseline chilled water energy use (ton-days) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

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BENCHMARKING

BENCHMARKING SUMMARY TABLE The table on the following page summarizes the annual energy consumption and performance metrics for the facility. This was done to provide a clear representation of the actual site and estimated source energy consumption for benchmarking and also for evaluation with energy savings opportunities. Energy use data for Fiscal Years 2011 – 2013 is shown in the table, along with an average of data from the three fiscal years.


Energy Use

Annual site electricity (kWh), chilled water (ton-hours) and 50 lb steam (klbs). These figures are not adjusted for central plant efficiencies (site to source conversion).

Performance Ratings

Performance ratings are provided for electricity in three units of measure: total kWh/ft2, equivalent total kBtu/ft2, and annual average W/ft2. Note that since electric demand utility data was not available for the building, an average demand was calculated based on the building’s annual electricity consumption (kWh) divided by the total number of hours in the year (8,760) and converted to Watts (1000 W/kW).

Performance ratings for chilled water and steam are provided in equivalent kBtu/ft2 based on measured site energy consumption. Estimates for equivalent source kWh/ft2 (electricity) and kBtu/ft2 (natural gas fuel) are also included based on the following assumptions:

Fuel-to-Steam Boiler Efficiency: 80%

Electric Chiller Plant Efficiency: 0.65 kW/ton

Steam-driven Chiller Efficiency: 2.1 COP

Annual Chilled Water Load Assumptions: 20% Steam-driven chillers, 80% Electric Chillers

The total site and source performance ratings sum the equivalent source ratings (kBtu/ft2) for electricity, chilled water, and steam, so that this building can be benchmarked against similar facilities, which may generate steam and chilled water in a central plant captured in the building electricity and natural gas meters.

Site Site Site Source

ft2 FY kWh ton-hrs klbs kWh/ft2 W/ft2 kBtu/ft2 kBtu/ft2 kWh/ft2 kBtu/ft2 kBtu/ft2 kWh/ft2 kBtu/ft2 kBtu/ft2 kBtu/ft2

FY11 3,812,917 1,303,008 19,895 14.8 1.69 50.4 60.61 3.2 7.2 77 0 96 188 165

FY12 4,076,971 1,253,904 19,583 15.8 1.80 53.9 58.32 3.1 6.9 76 0 95 188 166

FY13 4,063,194 803,688 18,895 15.7 1.80 53.8 37.38 2.0 4.5 73 0 92 164 157

3 Year Avg. 3,281,485 1,120,200 19,458 12.7 1.45 43.4 52.10 2.8 6.2 75 0 94 171 153

UMass Medical Center ACC Building Energy Use Data

ENERGY USE PERFORMANCE RATINGS

Floor

AreaFiscal Year Electricity CHW 50# Steam Electricity

Steam Total

Source Source

CHW

258,000


EQUEST MODEL CALIBRATION

Energy and cost savings were estimated using an existing eQuest model of the facility originally developed by Andelman & Lelek and modified to reflect current equipment characteristics, schedules, and internal loads. The model used the TMY3 weather file for Worcester, MA and was calibrated against monthly electricity use over a three year period from July 2010 – July 2013. The model was also calibrated for chilled water and steam use using monthly data obtained from the UMass central plant staff. The charts below compare the baseline utility use and the calibrated eQuest model predicted utility use.

Figure 7: ACC building eQuest model electricity use calibration chart. The baseline monthly electricity use utility data is shown in blue and the eQuest model predicted monthly electricity consumption is shown in red


Figure 8: ACC building eQuest model chilled water calibration chart. The baseline monthly chilled water utility data is shown in blue and the eQuest model predicted monthly chilled water energy consumption is shown in red.

Figure 9: ACC building eQuest model steam calibration chart. The baseline monthly steam utility data is shown in blue and the eQuest model predicted monthly steam consumption is shown in red.

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The table below summarizes the annual end-use energy distribution for electricity, steam, and chilled water at the facility as calculated by the baseline eQuest model. The pie chart on the following page illustrates the baseline eQuest model’s electricity end use using the figures shown in the table.

The “Miscellaneous Equipment” category in the table below can include any of the following equipment types: plug loads (such as appliances, computers, peripherals, laboratory equipment, freezers/refrigerators, etc.), transformer losses assigned to the building, exterior lighting, and elevators.

The following parameters were used to model the estimated miscellaneous loads in the ACC building, based on information gathered during walkthroughs and historical whole-building electricity use:

1. Corridor and Stairwell Plug Loads: 0.10 W/ft2

2. Office, Clinical Exam Room Plug Loads: 0.60 W/ft2

3. Tel/Data Room Plug Loads: 3.0 W/ft2

4. Peak Elevator Electric Demand: 60 kW

In addition, the following parameters were used to model interior lighting loads:

1. Office, Clinical Exam Room, and Corridor Lighting Power Density: 0.78 W/ft2

2. Stairwell Lighting Power Density: 0.60 W/ft2

Table 2: ACC Building eQuest model’s annual energy end-use for each meter (electricity, steam, and chilled water).

kWh MLb ton-hrs

Area Lighting 703,740 0 0

Task lighting 0 0 0

Misc. Equip. 799,424 1,284 0

Space Heating 803 19,214 0

Space Cooling 2,706 0 1,109,864

Heat Rejection 0 0 0

Pumps and Auxiliary 175,196 0 0

Ventilation Fans 1,636,362 0 0

Refrigeration 0 0 0

Heat Pump 0 0 0

Hot Water 0 0 0

Exterior 0 0 0

Total 3,318,232 20,499 1,109,864

BaselineAnnual Energy By

End Use


Figure 10: Pie chart showing ACC Building eQuest model’s annual electricity end use breakdown.


ENERGY CONSERVATION MEASURES

Energy Conservation Measures (ECMs) associated with the major air- and water-side equipment and terminal devices were identified following field investigations and a review of trend data from the facility’s Siemens building automation system. ECMs vary in scope from low cost measures limited to schedule, sequence, and set-point optimization, to more complex measures which may require larger capital investment associated with equipment replacement or retrofit.


ECM-01.01 (A) LIGHTING RETROFIT

MEASURE ECONOMICS SUMMARY ECM # 01.01 (a) Lighting Retrofit


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive

kWh $ ton-hr $ Mlb $ $ $ yrs

83,832 $8,383 0 $0 0 $0 $8,383 $116,710 13.9

BASE CASE The lighting consists of 1’ by 4’ one lamp 32 Watt T8 fixtures, and 2’x4’ two and three lamp 32 Watt T8 fixtures. There is a substantial number of 13 Watt recessed cans that contain 13 Watt compact fluorescents (CFLs). The facility also contains a large quantity of 2’x2’ two and three lamp 14 Watt T5 volumetric fixtures. The lens type on most fixtures is either prismatic or volumetric. The recessed cans do not have a lens. Occupancy sensors for lighting control are installed throughout the facility in the majority of spaces.

PROPOSED CASE This measure proposes to upgrade existing lamps and ballasts to newer high efficiency units where applicable. Refer to the Opinion of Probable Cost Table on the following page for a breakdown of proposed equipment types and quantities. We recommend replacing 4’ 32 Watt T8 lamps with high efficiency 25 or 28 Watt lamps and NEMA Premium (NP) electronic ballasts. We also recommend replacing CFLs and incandescent floods with LED lamps. The recommendations do not include fixture upgrades or replacement in an effort to present a more effective retrofit approach. There is no change recommended for the existing T5 fixtures.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in electricity use by installing high efficiency fluorescent lamps and more efficient ballasts. The energy savings calculations make estimates for annual run hours of each fixture based on information obtained from facilities and maintenance staff. The calculations assume that run hours remain the same in the proposed case.

ASSUMPTIONS The audit was performed, room-by-room, on all of floor A (with the exception of areas that were inaccessible), and floors one and two. Given the consistency on the floor plan and area/room type between floor two, and floors three, four and five, those floors were estimated based upon room size and corresponding fixture type and quantity from the audit of floor two. A high level walk through of those floors was performed and apparent differences captured in the audit data. Areas on floors six and seven that were identified on the floor plan as being


different from the preceding floors were reviewed and added to the audit. The remaining, similar areas on floors six and seven were extrapolated from the audit results of the floors below. Occupancy sensing and other lighting controls are excluded from this measure due to the nature of the spaces served and 24/7 building operation.


COST ESTIMATE The cost estimate for this measure is shown in the table below. The labor cost for the recommended retrofits are included in the material costs below.

B2Q Associates, Inc. Customer: UMASS MEDICAL Date: 12/24/2014

100 Burtt Rd. Ste. 212 Address: ACC Building Estimated By: KK

Andover, MA 01810 Checked By: PB

(978) 208 - 0609

Number Source Item Type Quantity Unit Cost Total Cost Unit Rate Workers Hours Each Labor Cost Total Cost

1 3-Audit

Retrofit - 1 Lamp 32 Watt T8 with NP Ballast

with 1 Lamp 28 Watt T8 with NP Ballast ea 114 $45 $5,130 $0 0 0 $0 $5,130

2 3-Audit

Retrofit - 3 Lamp 3 foot 30 Watt T8 with NP

Ballast with 3 Lamp 25 Watt T8 with HP Ballast ea 11 $60 $660 $0 0 0 $0 $660

3 3-Audit


Ballast with 2 Lamp 28 Watt T8 with NP Ballast ea 969 $55 $53,295 $0 0 0 $0 $53,295

4 3-Audit


Ballast with 3 Lamp 28 Watt T8 with NP Ballast ea 2 $60 $120 $0 0 0 $0 $120

4 3-Audit

Replace 13 Watt Compact Florescents lamps

(CFL's) with 5 Watt LED's ea 661 $5 $3,305 $0 0 0 $0 $3,305

Subtotal $62,510

1 Means

2 Vendor Quote Contingency 20% $12,600

3 Other Engineering 15% $11,300

4 Vendor Allowance Construction Administration 5% $3,800

Commissioning 20% $15,100

Construction Observation 10% $7,600

Project Closeout & Expenses 5% $3,800

Total $116,710

Opinion of Probable Construction Cost01-01 (a): Retrofit Lighting Fixtures

General Materials Labor

Sources


ECM-04.09 (A)-1 TIGHTEN OCCUPANCY SCHEDULES

MEASURE ECONOMICS SUMMARY ECM # 04.09 (a)-1 Tighten Occupancy Schedules


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


40,288 $4,835 35,207 $4,225 1,605 $16,047 $25,106 $30,625 1.2

BASE CASE The majority of thermal zones in the building are currently setback using a global occupancy schedule (Monday - Friday 5:30am - 7:30pm). However, there are areas in the building that have occupancy patterns that are not occupied as late as 7:30pm and could benefit from customized scheduling.

PROPOSED CASE We propose tightening the existing occupancy schedule in the areas of the building that are generally occupied during typical office hours to Monday - Friday 6:00am - 6:00pm. The proposed schedule and specific zones included in this measure will be reviewed with UMass Medical Facilities and Maintenance staff prior to implementation.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the increase in hours that zones are unoccupied as a result of tighter occupancy schedules. During the unoccupied mode, zone temperature set-points set back and VAV box airflow set-points are reset to 40% of their occupied minimums, resulting in less fan, heating, and cooling energy consumed at the VAV box and upstream AHU.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQUEST model. The run was performed on the zones listed in the table above that are served by the AHU-1,2,3,4 system. The parametric run changed the following parameters:

Base Case

COOL-TEMP-SCH: Health Cool Sch

o M-F 5:00am - 8:00pm: 72.0°F

o All other hours: 95°F

HEAT-TEMP-SCH: Health Heat Sch

o M-F 5:00am - 8:00pm: 72°F



MIN-FLOW-RATIO: 0.70

HMIN-FLOW-RATIO: 0.65

MIN-FLOW-SCH: Min Flow AS

o M-F 5:00am - 8:00pm: -999 [Calculate based on MIN-FLOW-RATIO]

o All other hours: 0.30

Proposed Case

COOL-TEMP-SCH: Prop Health Cool Sch

o M-F 6:00am - 6:00pm: 72.0°F


HEAT-TEMP-SCH: Prop Health Heat Sch

o M-F 6:00am - 6:00pm: 72°F







COST ESTIMATE The following estimate was developed using estimates for materials, labor, and programming costs. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable.


100 Burtt Rd. Ste. 212 Address: ACC Building Estimated By: PB

Andover, MA 01810 Checked By: KK

(978) 208 - 0609


1 3 Controls Programming ea 414 $0 $0 $150 1 0.15 $9,315 $9,315

2 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200

3 3 Contractor Commissioning ea 414 $0 $150 1 0.1 $6,210 $6,210

Subtotal $16,725

1 Means







Total $30,625

Sources

Opinion of Probable Construction CostECM-04.09 (a)-1: Tighten Occupancy Schedules



ECM-04.09 (A)-2 INSTALL NEW OCCUPANCY SENSORS FOR HVAC

CONTROL

MEASURE ECONOMICS SUMMARY ECM # 04.09 (a)-2 Install New Occupancy Sensors for HVAC Control


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


95,875 $11,505 30,917 $3,710 1,276 $12,761 $27,976 $708,110 25.3

BASE CASE The majority of thermal zones in the building are currently setback using a global occupancy schedule (Monday - Friday 5:30am - 7:30pm). Setbacks include lower minimum airflow set-points and the following temperature set-points: 60°F heating / 95°F cooling. However, there are areas throughout the building that are either continuously unoccupied or have occupancy patterns that differ from the global schedule. Most zones are equipped with occupancy sensors that control lighting operation, but do not interface with the building automation system and do not control HVAC set-points or schedules.

PROPOSED CASE We propose replacing all existing occupancy sensors with units that feature two outputs for sending signals to separate lighting and HVAC controllers. This would enable the global building automation system equipment schedule to be overridden in the event that an office zone becomes unoccupied during the day prior to 7:30pm.

We recommend maintaining a global occupied schedule start time on each week day in order to ensure that zones are able to recover to occupied temperature set-points. If no occupancy is detected by the sensor for a duration of 60 minutes after the start of the normally occupied period, the zone would then be set-back until occupancy is detected.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the increase in hours that zones are unoccupied due to occupancy sensor control. During the unoccupied mode, zone temperature set-points set back and VAV box airflow set-points are reset to 40% of their occupied minimums, resulting in less fan, heating, and cooling energy consumed at the VAV box and upstream AHU.

The energy savings associated with this measure were estimated using a parametric run of the eQuest model using the results of ECM-7.1 as the baseline for savings calculations. This was done in order to account for the overlap between the two measures. The run was performed


on the approximately 50% of zones that are served by the AHU-1,2,3,4 system to simulate the benefits of installing occupancy sensors. The parametric run changed the following parameters:

Base Case


o M-F 5:00am - 8:00pm: 72.0°F



o M-F 5:00am - 8:00pm: 72°F







Proposed Case - Applied to Approximately 50% of Thermal Zones

COOL-TEMP-SCH: Prop Health Cool Sch

o M-F 7:00am - 12:00pm, 1:00pm - 4:00pm: 72.0°F


HEAT-TEMP-SCH: Prop Health Heat Sch

o M-F 7:00am - 12:00pm, 1:00pm - 4:00pm: 72.0°F





o M-F 7:00am - 12:00pm, 1:00pm - 4:00pm: -999 [Calculate based on MIN-FLOW-RATIO]







(978) 208 - 0609


1 3 Occupancy Sensors ea 414 $150 $62,100 $150 1 2 $124,200 $186,300

2 3 Controls Points ea 414 $250 $103,500 $150 1 1 $62,100 $165,600

3 3 Controls Programming ea 414 $0 $150 1 1 $62,100 $62,100

4 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $421,410

1 Means







Total $708,110

Opinion of Probable Construction CostECM-04.09 (a)-2: Install Occupancy Sensors for HVAC Control


Sources


ECM-09.00 (A) RETROFIT AHU-5 SUPPLY FAN WITH VFD

MEASURE ECONOMICS SUMMARY ECM # 09.00 (a) Retrofit AHU-5 Supply Fan with VFD


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


8,648 $1,038 0 $0 0 $0 $1,038 $23,000 22.2

BASE CASE AHU-5 is a 100% recirculation constant volume air handling unit with a 5 hp supply fan that provides mechanical cooling for Electric Room 801 in the penthouse. The system is configured to cycle the supply fan on as needed to meet the zone cooling set-point. A review of historical trend data showed that the cycle time for the AHU ranges between 30 - 120 minutes, and when the system was running, the chilled water valve was only partially open, indicating that the unit is typically operating at part load. Figure 11 on Page 38 shows a sample weeklong period of operation including the supply fan status, chilled water valve position, zone temperature, and discharge air temperature.

PROPOSED CASE We propose retrofitting the AHU-5’s supply fan with a VFD and revising the existing sequence of operation to minimize fan power. We recommend operating the supply fan continuously at minimum speed (15 Hz, adjustable) and modulating the chilled water valve to maintain the zone temperature set-point. If the chilled water valve is fully open and the zone temperature set-point is not met, the supply fan speed would slowly increase as necessary to meet the set-point. The reverse would occur once the set-point is met.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in AHU-5’s fan energy that is used to meet the zone cooling load.

The energy savings associated with this measure were estimated using a one-line spreadsheet model. Trend data was used to estimate the existing cycling ratio, or percentage of time spent running. It was estimated that the proposed VFD unit would run continuously at an average VFD speed equal to the cycling ratio of the base case. A VFD exponent of 2.5 was estimated, based on the low minimum static pressure requirements of the supply fan.


Figure 11: The trend screenshot below shows typical operation of AHU-5 over a 10 day period in July. The system maintains the zone temperature (RED) to between 76-80°F by cycling on every 30-120 minutes. The supply temperature (ORANGE) while running with the chilled water valve (PINK) partially open is never lower than 70°F.




100 Burtt Rd. Ste. 212 Address: ACC Building Estimated By: JAB

Andover, MA 01810 Checked By:

(978) 208 - 0609


1 3 5 HP VFD est 1 $2,500 $2,500 $150 1 16 $2,400 $4,900

2 3 Controls - 4pts ea 4 $1,000 $4,000 $150 1 4 $2,400 $6,400

2 3 As-built ea 1 $0 $150 1 4 $600 $600

3 3 Contractor Commissioning ea 1 $0 $150 1 8 $1,200 $1,200

Subtotal $13,100

1 Means



4 Vendor Allowance Construction Administration 5% $800



Project Closeout & Expenses 5% $800

Total $23,000

Opinion of Probable Construction CostECM-09.00 (a): Retrofit AHU-5 Supply Fan with VFD


Sources


ECM-18.00 (A)-1 REPLACE WEATHER STATION

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-1 Replace Weather Station


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


251 $30 39,269 $4,712 -23 -$226 $4,516 $12,700 2.8

BASE CASE Historical trend logs show that the building’s outdoor air temperature sensor is consistently reading approximately 5°F higher than the sensors for other buildings on the UMass Medical campus. The disparity was found to occur during the day and at night, which suggests that calibration drift may be the root cause as opposed to improper placement or shielding. A higher temperature measurement during daylight hours only often indicates that the sensor is picking up additional heat from direct or reflected radiation. Since the sensor for ACC is also reading higher at night, calibration is the most likely cause. Figure 12 on Page 42 shows a comparison between ACC’s outdoor air temperature and the Hospital’s outdoor air temperature measurement.

Since the building’s four AHUs feature a comparative enthalpy economizer strategy, the accuracy of temperature and humidity sensors are crucial to efficient operation during mild weather. Trend data shows that the apparent sensor drift is preventing airside economizer operation when conditions are appropriate.

PROPOSED CASE We recommend calibrating the building’s outdoor air weather station, including temperature and relative humidity sensors, to improve the effectiveness of the existing comparative enthalpy economizer strategy. We also recommend implementing a schedule to calibrate these sensors on an annual basis going forward to maintain the persistence of savings associated with this measure.

This measure will reduce mechanical cooling energy used at the four AHUs during periods when the outdoor air enthalpy is between 0-3.5 Btu/lb less than the return air enthalpy of each AHU. This range approximately corresponds to an average sensor drift of 5°F, with some variation due to fluctuations in relative humidity.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in mechanical cooling energy that is used when economizer was inappropriately locked-out in the base case as a result of the outdoor air temperature reading higher than actual.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-1,2,3,4 and changed the economizer’s comparative enthalpy enable offset (Outdoor Air Enthalpy < Return Air Enthalpy) from 3.5 Btu/lb in the base case to 0 Btu/lb in the proposed case. The 3.5 Btu/lb existing case offset represents the enthalpy differential corresponding to the outdoor air temperature sensor drift of 5°F at an average outdoor air relative humidity of 65%. By implementing a positive offset in the base case eQuest model, the economizer sequence is limited to operate only when the outdoor air enthalpy is less than the return air enthalpy by 3.5 Btu/lb, which reduces the number of hours the economizer can be enabled.


Figure 12: The trend screenshot below shows the difference between the ACC outdoor air temperature measurement (RED) and the Hospital outdoor air temperature measurement (BLUE). The difference ranges between 3-10°F during the year, which an average of 5°F.






(978) 208 - 0609


1 2

New Weather Station(s) -incl redundant

reference station ea 2 $1,000 $2,000 $150 1 8 $2,400 $4,400

3 3 Programming ea 1 $0 $150 1 4 $600 $600

3 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


5 $0 $0 $0

Subtotal $7,400

1 Means




Commissioning 5% $500

Construction Observation 10% $900


Total $12,700

Opinion of Probable Construction Cost ECM-18.00 (a)-1: Replace Weather Station


Sources


ECM-18.00 (A)-2 CALIBRATE FLOW STATIONS & REDUCE UNOCCUPIED OUTDOOR

AIR

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-2 Calibrate Flow Stations & Reduce Unoccupied Outdoor Air


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-3,015 -$362 63,186 $7,582 2,039 $20,394 $27,614 $35,100 1.3

BASE CASE According to the as-built controls submittal for the building, AHU-1,2,3, and 4 are equipped with separate modulating minimum and maximum outdoor air dampers. The minimum outdoor air dampers are specified to modulate in order to maintain an effective outdoor airflow set-point based on return and zone air CO2 measurements. The minimum outdoor airflow set-point should between 40% - 100% of design outdoor airflow, corresponding to 7,800 cfm - 19,500 cfm. If the AHU return air CO2 measurement is below set-point (750 ppm) and all zone CO2 measurements are below alarm (950 ppm), then the minimum outdoor airflow set-point should be at its lowest.

Historical trend logs show that each of the four major air handling units have an actual minimum outdoor air ratio ranging between 32% - 48%, which corresponds to a minimum airflow of approximately 11,500 cfm - 24,000 cfm depending on the total supply airflow. The data suggests that none of the AHUs reach the 7,800 cfm minimum described in the original sequence and minimum outdoor airflow was not observed to reset during unoccupied periods when the building’s main exhaust fans shut down.

The trend logs also suggest that the outdoor airflow stations may be out of calibration. Minimum outdoor airflow was calculated using mixed air temperature, return air temperature, and an accurate outdoor air temperature, and then compared against the measured minimum outdoor air flow. In all cases, the calculated flow using temperatures was greater than the measured flow.

PROPOSED CASE We propose calibrating the outdoor airflow stations on AHU-1, 2, 3, and 4 and implementing a new outdoor air sequence of operation. Specifically, each AHU would maintain an occupied minimum airflow set-point of 12,500 cfm, which would reset higher as necessary to maintain the return air CO2 set-point of 750 ppm or if any individual zone CO2 exceeds 950 ppm. A minimum set-point of 12,500 cfm per AHU is recommended based on an analysis of building exhaust fans to maintain proper building pressurization during occupied periods.


In addition, we recommend a further reduction in outdoor airflow during unoccupied periods when the building’s six general and toilet exhaust fans shut down. Combined, these fans have a design flow of 42,400 cfm and are currently scheduled Monday-Friday 5:30am - 7:30pm. During unoccupied periods, the total building exhaust flow decreases by nearly 90% and as a result, less outdoor air is necessary to maintain pressurization. Similarly, since the building is primarily unoccupied at night and on weekends, less ventilation is necessary to maintain CO2 set-points. We recommend reducing the minimum outdoor airflow set-point on each of the two running AHUs to 3,000 cfm during unoccupied periods, resulting in a total ventilation rate of 6,000 cfm.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating and mechanical cooling energy that is necessary to condition excess amounts of outdoor air.

The energy savings associated with this measure were estimated using a parametric run of the eQuest model, using the results of ECM-2.2 as the baseline for savings calculations. This was done in order to avoid double-counting savings between the two measures. The run was performed on AHU-1,2,3,4 and changed the following parameters:

Base Case

Outdoor airflow calculation type: Fraction of hourly flow

Minimum outdoor airflow ratio: 43%

Minimum outdoor airflow schedule: None

Proposed Case

Outdoor airflow calculation type: Fraction of design flow

Minimum outdoor airflow ratio: 19.2% [Occupied]

Minimum outdoor airflow schedule:

o 19.2% [Monday – Friday 5:30am – 7:30pm]

o 5% [Monday – Friday 7:30pm – 5:30am, All Day Saturday – Sunday]






(978) 208 - 0609


1 3 Controls ea 4 $0 $150 1 4 $2,400 $2,400

2 3 TAB ea 4 $0 $150 2 8 $9,600 $9,600

3 4 Damper/Actuator Allowance ea 4 $500 $2,000 $150 2 2 $2,400 $4,400

4 3 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $19,400

1 Means







Total $35,100

Sources

Opinion of Probable Construction CostECM-18.00 (a)-2: Calibrate Flow Stations & Reduce Unoccupied Outdoor Air



ECM-18.00 (A)-3 STATIC PRESSURE RESET ON AHUS 1-4

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-3 Static Pressure Reset on AHUs 1-4


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


162,714 $19,526 27,859 $3,343 -182 -$1,823 $21,046 $38,200 1.8

BASE CASE AHU-1, 2, 3, and 4 are variable volume units that control to a fixed duct static pressure set-point of 1.5” WC. The majority of terminal boxes served by these units have minimum airflow set-points of approximately 25% of maximum, indicating an opportunity to reduce duct static during periods of low load.

PROPOSED CASE We propose resetting the duct static pressure set-point on AHU-1, 2, 3, and 4 using a new cascading control algorithm. Every 15 minutes the BAS will perform a damper position “high select” on all VAV boxes served by the AHUs. If the average of the top five (user selectable from 1 to 10) “high select” boxes is between 85% and 90% open the system shall hold its current discharge pressure set-point. If the average is below 80% open the BAS logic shall cascade its duct static pressure set-point down to a low of 1.0” WC. If the average of the top five boxes is greater than 90% then the system duct static pressure set-point shall cascade up to a maximum of 1.85” WC. The cascading reset loop shall be tuned to avoid unnecessary hunting.

This proposed sequence ensures that sufficient static pressure is maintained in order to supply enough airflow to meet demand, while allowing for “rogue“ non-critical zone(s) that are consistently at or near maximum flow.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in AHU fan horsepower needed to maintain a lower duct static pressure set-point when the system is at part load.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-1,2,3,4 and changed the supply fan “EIR f(PLR)” performance curve that calculates fan input power as a function of airflow part load ratio. The curve used in the base case is the standard curve available from the eQuest library. A custom curve was developed for the proposed case to model a demand-based duct static pressure reset. At maximum a fan part load ratio of 30%, the proposed fan energy input ratio (EIR) was 0.297 compared to an existing EIR of 0.372, resulting in 20% savings at lowest part load. EIR is defined to be the ratio of electric energy input (Btu/hr) to the rated energy


output (Btu/hr) of the fan. The chart below illustrates the existing and proposed can fan curves used to estimate energy savings.

Figure 13: Existing and proposed case fan curves [EIR = f(Part Load Ratio)] used to model demand-based static pressure reset energy savings.

0

0.2

0.4

0.6

0.8

1

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Ele

ctri

c In

pu

t R

atio

Part Load Ratio

AHU-1,2,3,4 Static Pressure Reset Curve

Existing Case Curve (No SP Reset) Proposed Case Curve (SP Reset)


Figure 14: The trend screenshot below shows that duct static pressure is maintained at the set-point of 1.85” WC.






(978) 208 - 0609


1 3

Controls Programming-Assumes polling

zone based feedback ea 4 $0 $150 1 24 $14,400 $14,400

2 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


4 $0 $0 $0

5 $0 $0 $0

Subtotal $20,400

1 Means







Total $38,200

ECM-18.00 (a)-3: Static Pressure Reset on AHUs 1-4

Opinion of Probable Construction Cost


Sources


ECM-18.00 (A)-4 REPROGRAM DISCHARGE TEMPERATURE RESET ON

AHUS 1-4

MEASURE ECONOMICS SUMMARY ECM # 18.00-7 Reconfigure Discharge Temperature Reset on AHUs 1-4


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-3,020 -$302 73,412 $8,809 280 $2,803 $11,311 $20,300 1.8

BASE CASE AHU-1, 2, 3, and 4 are equipped with hot water preheat, chilled water cooling, and control to a discharge air temperature set-point that resets based on zone temperature error. The sequence of operation states that if any zone is more than 1°F above the effective zone cooling set-point, the AHU discharge air temperature set-point resets to the minimum of 55°F. Historical trend data available between May – September shows that the discharge air temperature set-points on any of the four major AHUs did not reset above the 55°F minimum.

Terminal box trends show that many zones temperatures that were not meeting their effective temperature set-points, which is restricting the AHU discharge set-point from resetting higher. The primary air damper positions on boxes in these zones were found to only partially open, however, suggesting that the boxes may need to be rebalanced for the current loads.

PROPOSED CASE We recommend rebalancing terminal boxes that are unable to meet zone temperature set-points and reconfigure the existing demand-based discharge temperature reset to work in tandem with static pressure reset proposed in ECM-3. The discharge air temperature set-point on AHUs 1-4 is not currently resetting because zone temperature set-points are not being met in several zones. This is likely due to improper minimum and maximum airflow set-points on the terminal boxes in these zones. As a result, we propose rebalancing these zones so that they are able to accurately meet zone set-points. The proposed sequence of operation is to reset the discharge temperature set-point higher only after the AHU duct static pressure set-point has reached minimum. This will reduce the potential for the two reset sequences to fight each other, which would reduce their energy savings.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in chilled water energy consumption and terminal reheat and perimeter baseboard energy consumption during periods when the discharge


temperature set-point resets higher. A comparatively small fan energy penalty is modeled as part of the measure, since higher primary air temperatures may require zones with larger internal loads to supply more airflow to meet cooling set-points during the shoulder seasons.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-1,2,3,4 and changed the following parameters:

Base Case

Cool Control: Warmest

Reset Priority: Simultaneous

Maximum Cooling Reset Temp: 55°F

Minimum Cooling Reset Temp: 55°F

Proposed Case


Reset Priority: Simultaneous



In the base case, the “maximum cooling reset temp” of 55°F was specified to limit the demand-based reset from enabling a set-point than 55°F, based on observations made from historical trend data.


Figure 15: The trend screenshot below shows the discharge air temperatures for AHU-1, 2, 3, and 4 between 6/1/2014 - 7/30/2014. When in the occupied mode, each AHU discharges at a constant 55°F.






(978) 208 - 0609


1 3

Controls Programming-Assumes polling

zone based feedback and SP reset is in

place ea 4 $0 $150 1 8 $4,800 $4,800

2 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


$0 $0 $0

$0 $0

Subtotal $10,800

1 Means







Total $20,300

Opinion of Probable Construction CostECM-18.00 (a)-4: Reconfigure Discharge Temperature Reset on AHUs 1-4


Sources


ECM-18.00 (A)-5 REDUCE AHU-2 OA DAMPER MINIMUM POSITION

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-5 Reduce AHU-2 OA Damper Minimum Position


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-236 -$28 5,654 $678 320 $3,202 $3,852 $7,700 2.0

BASE CASE Historical trend data shows that the maximum outdoor air (economizer) damper on AHU-2 does not close during periods when economizer and demand-controlled ventilation sequences are disabled. The damper’s minimum position was observed to be 20%, compared to a 0% minimum on the other three identical AHUs. The maximum outdoor air dampers can have a 0% minimum position because modulating minimum outdoor air dampers are used to maintain sufficient outdoor airflow at all times for building pressurization and ventilation.

The minimum outdoor air ratio calculated for AHU-2 using outdoor, return, and mixed air temperatures was the highest of all four AHUs at approximately 46%.

PROPOSED CASE We recommend reducing the minimum position of the maximum outdoor air damper on AHU-2 from 20% to 0%. This will reduce heating and cooling energy consumption associated with conditioning additional outdoor air during periods when economizer and demand-controlled ventilation sequences are disabled.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating and mechanical cooling energy that is necessary to condition excess amounts of outdoor air.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the AHU-1,2,3,4 system and changed the following parameters:

Base Case

Minimum OA Schedule: Min OA Annual

Minimum outdoor airflow ratio: 45% [all hours]

Proposed Case

Minimum OA Schedule: Min OA Annual


Minimum outdoor airflow ratio: 43% [all hours]






(978) 208 - 0609


1 3 Controls Programming ea 1 $0 $150 1 4 $600 $600

2 3 TAB ea 1 $0 $0 $150 1 8 $1,200 $1,200

3 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


5 $0 $0 $0

Subtotal $4,200

1 Means

2 Vendor Quote Contingency 20% $900

3 Other Engineering 15% $800





Total $7,700

Opinion of Probable Construction CostECM-18.00 (a)-5: Reduce AHU-2 OA Damper Minimum Position


Sources


ECM-18.00 (A)-6 CALIBRATE ZONE CO2 SENSORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-6 Calibrate Zone CO2 Sensors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 19,892 $2,387 0 $0 $2,387 $52,200 21.9

BASE CASE Historical trend data shows that the maximum outdoor air (economizer) damper on AHU-2 was open up to 100% in the summer when the outdoor air enthalpy was greater than the return enthalpy and economizer should be disabled. The demand controlled ventilation sequence should have also been disabled based on return air CO2, which peaked at 510 ppm during an occupied period in July. According to the original sequence of operation, demand controlled ventilation may also be enabled if any zone’s CO2 measurement exceeds an alarm set-point of 950 ppm. Although trend data was not available for all zones, it is possible that one or more zone CO2 measurements were above this alarm threshold, activating the DCV sequence and causing the outdoor air damper to open above minimum.

A portable CO2 sensor was used to determine if concentrations above 950 ppm were typical in densely occupied zones, or if sensor calibration may be an issue. Measurements were taken at approximately 11:30am on a weekday in a densely occupied area of the fourth floor, which according to an Operating Engineer was estimated to have the highest CO2 concentration in the building due to dense occupancy. However, the highest measurement recorded during the test was 550 ppm. This suggests that one or more zone CO2 sensors may be out of calibration, especially if these sensors have not been calibrated since installation.

PROPOSED CASE We recommend calibrating (40) zone CO2 sensors to reduce heating and cooling loads during periods when the economizer sequence is disabled. We also recommend reviewing AHU-2’s return air CO2 set-point and zone air CO2 alarm thresholds to determine if an overridden set-point is causing the demand controlled ventilation sequence to activate instead of a miscalibrated sensor.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating and mechanical cooling energy that is necessary to condition excess amounts of outdoor air when the demand-controlled ventilation sequence was incorrectly enabled due to faulty CO2 sensor measurements.


The energy savings associated with this measure were estimated using a bin spreadsheet model. Trend data collected from the Siemens BAS between May and August 2014 was used to determine the existing case average outdoor air ratio for AHU-2 during periods when economizer was disabled but the max-outdoor air damper position was greater than 0%. In the proposed case, the outdoor air fraction was set to 32% to model the benefits of correcting the issue with the demand-controlled ventilation sequence and closing the maximum-outdoor air damper.






(978) 208 - 0609


1 3 Calibrate CO2 Sensors ea 40 $0 $150 1 4 $24,000 $24,000

2 3 As-built ea 1 $0 $150 1 0 $0 $0


4 $0 $0 $0

5 $0 $0 $0

Subtotal $30,000

1 Means







Total $52,200


Sources

Opinion of Probable Construction CostECM-18.00 (a)-6: Calibrate Zone CO2 Sensors


ECM-18.00 (A)-7 REPLACE AHU-4 RETURN AIR CO2 SENSOR

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-7 Replace AHU-4 Return Air CO2 Sensor


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 6,703 $804 0 $0 $804 $3,500 4.4

BASE CASE Historical trend data shows that the return air CO2 measurement on AHU-4 typically reached over 1,000 ppm and as high as 1,120 ppm each weekday. See Figure 16 on Page 63 for a chart that shows the return air CO2 trend over time. It is suspected that this sensor is out of calibration based on the following observations:

The return air ducts for each of the four major AHUs are headered on each floor, which should allow for partial mixing of the return air

The return air CO2 measurements on the three other AHUs are consistently lower than AHU-4. For example, AHU-3’s peak CO2 measurement of 710 ppm on 7/14/2014 is the closest in magnitude to AHU-4, a 390 ppm difference.

In the sample of zone trend data downloaded, the peak zone CO2 measurement found was 810 ppm. No zone CO2 measurements reviewed approached or exceeded the typical return air CO2 of AHU-4.

As a result of the elevated return air CO2 measurement, the maximum outdoor air damper on AHU-4 was found to be above minimum position during occupied periods throughout the summer months when the economizer sequence was disabled.

PROPOSED CASE We recommend replacing the return air CO2 sensor on AHU-4 to improve the efficiency of the demand-controlled ventilation sequence by providing accurate CO2 concentration feedback to the controls. This should reduce the amount of outdoor air that must be conditioned during periods when economizer is disabled.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating and mechanical cooling energy that is necessary to condition excess amounts of outdoor air when the demand-controlled ventilation sequence was incorrectly enabled due to faulty CO2 sensor measurements.

The energy savings associated with this measure were estimated using a bin spreadsheet model. Trend data collected from the Siemens BAS between May and August 2014 was used to


determine Return air conditions, supply air conditions, and mixed air conditions. TMY3 weather data for Worcester, MA was used was used to determine the exact amount of run hours spent by the unit in each temperature bin. Savings were taken by comparing the energy use of AHU-4 under the current air mixing behavior and under a situation where the OA dampers remain at minimum position for all hours when economizer mode is locked out. The minimum outside air percentage used to calculate proposed case energy use was 30%.


Figure 16: The trend screenshot below shows a typical two-week period of Return Air CO2 Concentration (RED) and supply fan speed (BLUE). The highlighted timestamp on 7/7/2014 at 11:45 am indicates the return air CO2 reached nearly 1,100 ppm during the occupied period. This is inconsistent with field measurements taken using a properly calibrated handheld meter.






(978) 208 - 0609


1 3 Replace CO2 Sensor ea 1 $500 $500 $150 1 4 $600 $1,100

2 3 As-built ea 1 $0 $150 1 0 $0 $0

3 3 Contractor Commissioning ea 1 $0 $150 1 4 $600 $600

4 $0 $0 $0

5 $0 $0 $0

Subtotal $1,700

1 Means







Total $3,500

Opinion of Probable Construction CostECM-18.00 (a)-7: Replace AHU-4 Return Air CO2 Sensor


Sources


ECM-18.00 (A)-8 REDUCE VAV UNOCCUPIED FLOW SET-POINTS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-8 Reduce VAV Unoccupied Flow Set-points


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-4,505 -$541 183,954 $22,075 2,429 $24,293 $45,827 $389,900 8.5

BASE CASE The majority of the building’s VAV boxes are configured to maintain an unoccupied airflow set-point that is 40% of the occupied minimum airflow set-point and approximately 25% of the maximum VAV airflow. Historical trend data shows that this continuous supply of conditioned air limits the zones from ever reaching unoccupied temperature set-points. Although the unoccupied set-points are relatively aggressive (60°F heating / 95°F), the full benefit of the set-back is not being realized as a result of the continuous airflow.

PROPOSED CASE We recommend that all VAV box minimum airflow set-points be reduced to 0 cfm during the unoccupied mode while maintaining the existing zone temperature set-backs. According to ASHRAE 62.1-2013, the most recent standard for facility ventilation requirements, ventilation should be supplied to a zone when it is expected to be occupied. Ventilation is not required during periods when a zone is unoccupied and as a result, supply airflow set-points can be reduced to 0 cfm in areas without continuous exhaust flow and/or space pressurization requirements.

In the proposed case, perimeter hot water baseboard shall be used as the first stage of heat if the zone reaches the unoccupied heating set-point. If the zone cannot meet the set-point with the baseboard on, the VAV airflow set-point shall be reset higher and the reheat valve shall open as necessary to meet the set-point. In zones equipped with fan-powered terminal boxes, the primary air damper shall remain closed during the unoccupied period and the fan and heating coil shall be used to maintain the zone heating set-point.

If the zone reaches the unoccupied cooling set-point, the VAV airflow set-point shall be reset to maintain the set-point. At all times during the unoccupied mode, VAV airflow set-points shall be limited to their current unoccupied minimums.

As part of this measure, we recommend a revision to the existing AHU staging sequence that currently shuts down two out of four AHUs during unoccupied periods. Due to the proposed reduction in unoccupied minimum airflow set-points throughout the building, we propose shutting down a third unit if the following conditions are met:


The supply fan on each running AHU reaches minimum speed (20 Hz)

Duct static pressure is greater than the effective set-point

Once the third AHU is shut down, it would remain off until the running unit’s supply fan speed reaches 45 Hz.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan, heating, and mechanical cooling energy that is necessary to supply excess conditioned air to zones during unoccupied periods. VAV reheat and perimeter baseboard heating savings is not anticipated since the majority of zones do not currently reach the unoccupied heating set-point throughout the year.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the zones served by the AHU-1,2,3,4 system and changed the following parameters:

Base Case

MIN-FLOW-SCH: Min Flow Ratio

o Monday - Friday 5:00am - 8:00pm: 0.70


Proposed Case

MIN-FLOW-SCH: ECM#6.1 Min Flow Ratio








(978) 208 - 0609


1 3 VAV Controls ea 414 $0 $0 $150 1 0.5 $31,050 $31,050

2 3 AHU Controls (Shut Down 3rd AHU) ea 1 $0 $0 $150 1 24 $3,600 $3,600

3 3 TAB ea 414 $0 $0 $150 1 2 $124,200 $124,200

4 4 Damper/Actuator Allowance ea 20 $500 $10,000 $150 2 4 $24,000 $34,000

5 3 As-built ea 414 $0 $0 $150 1 0.25 $15,525 $15,525

6 3 Contractor Commissioning ea 414 $0 $0 $150 1 0.25 $15,525 $15,525

Subtotal $223,900

1 Means







Total $389,900


Sources

Opinion of Probable Construction CostECM-18.00 (a)-8: Reduce VAV Box Unoccupied Flow Set-points


ECM-18.00 (A)-9 REPROGRAM ZONE SET-POINTS & IMPLEMENT DEAD-BAND

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-9 Reprogram Zone Set-points & Implement Dead-band


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


271,440 $32,573 123,813 $14,858 3,595 $35,949 $83,380 $55,650 0.7

BASE CASE Historical trend data shows that zones throughout the building have occupied temperature set-points that range between 68-76°F, potentially contributing to inefficient operation and simultaneous heating and cooling. The control sequence of operation does not describe any limitations on local thermostat set-point adjustment and trends suggest that occupants have a band of at least 8°F. In addition, zones were observed to have a single effective set-point during occupied periods and a mode point that defined whether the zone was in heating or cooling. Some zones were observed to switch between heating and cooling modes throughout the day as the zone temperature cycled around the single effective set-point.

PROPOSED CASE We recommend setting global occupied and unoccupied heating and cooling zone temperature set-points and allowing a maximum local adjustment of +/- 2°F by occupants. We recommend implementing occupied set-points of 71°F heating and 73°F cooling (2°F dead-band), and maintaining the existing unoccupied set-points of 60°F heating and 95°F cooling. Implementing separate occupied heating and cooling set-points with at least a 2°F dead-band may reduce energy consumption by allowing zones to ‘drift’ between the set-points before reheat is needed or additional cooling airflow is supplied.

Note that if ECM-10 is implemented, we recommend reducing the unoccupied cooling set-point to 85°F in order to reduce zone recovery time on design cooling days.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from an overall reduction in conditioned airflow and reheat energy used to meet temperature set-points that are higher or lower than the systems were designed for. In addition, savings result from a reduction in simultaneous heating and cooling that may be occurring in adjacent zones with different temperature set-points. Mixing between these zones can cause equipment to ‘fight’ each other, with one VAV box typically in cooling and the other in heating.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the zones served by the AHU-1,2,3,4 system and changed the following parameters:

Base Case

MIN-FLOW-SCH: Min Flow Ratio




o Monday - Friday 5:00am - 8:00pm: 72°F





Proposed Case

MIN-FLOW-SCH: ECM#6.2 Min Flow Ratio



COOL-TEMP-SCH: ECM#6.2 Health Cool Sch



HEAT-TEMP-SCH: ECM#6.2 Health Heat Sch




Figure 17: Level 3 VAV 051 - The trend screenshot below shows the VAV box switching between heating and cooling modes with an estimated 1°F deadband. The highlighted timestamp indicates the reheat valve (PINK) opens directly after the zone temperature (ORANGE) reaches 1°F below the effective set-point (BLUE). Before this point in time, the equipment had been in cooling mode, as indicated by the airflow (RED) being greater than minimum (450 cfm) and the reheat valve being closed.






(978) 208 - 0609



2 3 As-built ea 1 $0 $0 $150 1 4 $600 $600


4 $0 $0 $0

5 $0 $0 $0

Subtotal $31,650

1 Means







Total $55,650

Opinion of Probable Construction CostECM-18.00 (a)-9: Reprogram Zone Set-points & Implement Dead-band


Sources


ECM-18.00 (A)-10 RECONFIGURE UNOCCUPIED ZONE TEMPERATURE

CONTROL

MEASURE ECONOMICS SUMMARY ECM # 18.00 (a)-10 Reprogram Unoccupied Zone Temperature Control


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 0 $0 361 $3,615 $3,615 $8,613 2.4

BASE CASE A review of historical trend data has shown that each zone has a single effective unoccupied set-point that is set based on a mode point, which can be either heating or cooling. In the heating mode, the zone’s unoccupied temperature set-point is 60°F and in the cooling mode the unoccupied temperature set-point is 95°F. However, the boxes listed in Table 3 below were found to be in full reheat during the unoccupied period when the effective set-point was 95°F. It is possible that an error in their control sequences is resulting in the device’s mode not matching the effective unoccupied set-point. See Figure 18 on Page 74 for a trend screenshot illustrating this issue on Level 1 VAV 010.

Table 3: Terminal boxes identified to be reheating during the unoccupied period with an effective set-point of 95°F

LEVEL-1 LEVEL-2 LEVEL-3 LEVEL-5 LEVEL-6

10 35 11 000CC 10

033E 36 52 20 14

53 42 56 30 20

65 56 71 104 48

82 107 5C15 64

120 117 096A

210A 121 233

2C02 208

3035

PROPOSED CASE We recommend reconfiguring unoccupied temperature control to allow zones to drift between unoccupied heating and cooling set-points without establishing a mode. For example, during the unoccupied period, the heating set-point would be 60°F and the cooling set-point would be 95°F. Each terminal box would remain at minimum airflow and reheat would be disabled until the zone temperature reaches either of the unoccupied set-points. Zones would then be maintained as necessary to the appropriate set-point.


ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in reheat energy used by terminal boxes that were observed to be reheating when unnecessary during the unoccupied mode. This issue was not found to impact the fan or cooling energy consumption of surrounding zones during overnight and weekend periods since the unoccupied zone cooling set-point of 95°F was not observed to be reached at any point. However, the additional heating supplied by the faulty boxes may result in excess energy consumption during the recovery period as zone temperatures are brought down to occupied set-points.

The energy savings associated with this measure were estimated using a bin spreadsheet model. Energy savings were modeled for a typical VAV box that was observed to be 100% reheating during the unoccupied period. The energy model assumed that the reheat coils were designed for a 20°F air temperature rise with coil valves 100% open. The results were then extrapolated to all other VAV boxes using individual minimum airflow set-points to appropriately scale the savings. Hot water energy savings were converted to steam savings using an estimated heat exchanger and distribution efficiency of 97% and a steam heating value of 1,000 Btu/lb.

74 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Benedict

Figure 18: Level 1 VAV 010 - The trend screenshot below shows how the zone reheat valve (LIGHT BLUE) is opening during each unoccupied period in an attempt for the system to meet the effective unoccupied set-point (DARK BLUE) of 95°F. Although the VAV box should be in a setback cooling mode based on the high unoccupied set-point, an unknown error is causing the box to enter the heating mode.






(978) 208 - 0609



2 3 As-built ea 1 $0 $0 $150 1 4 $600 $600


Subtotal $4,313

1 Means







Total $8,613

Opinion of Probable Construction CostECM-18.00 (a)-10: Reconfigure Unoccupied Zone Temperature Control


Sources


BENEDICT EXECUTIVE SUMMARY TABLE


ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


01.01 (b) Lighting Retrofit 57,116 0 0 $5,712 $110,150 19.3

02.01 (b) Install Occupancy Sensors 129,208 9,802 -293 $11,171 $67,100 6.0

04.09 (b)-1 FCU Controls Upgrade 244,142 25,308 3,297 59,801 $848,600 14.2

04.09 (b)-1a Unoccupied Set-backs & Zone Temperature Control 116,132 25,453 2,159 $35,636 - -

04.09 (b)-1b Close FCU OA Dampers During Unoccupied Periods -2,032 -145 1,138 $11,160 - -

04.09 (b)-1c Retrofit FCU Fans with EC Motors 130,042 0 0 $13,004 - -

04.09 (b)-2 HW Loop dP Reset 7,258 0 -22 $501 $8,100 16.2

12.04 (b) Install Low-E Window Film 5,083 5,661 7 $1,253 $90,800 72.5

442,807 40,771 2,989 $78,438 $1,124,750 14.3TOTALS



The Benedict building on the UMMC campus, constructed in 1992, is approximately 80,000 ft2 and consists of three above grade levels and one basement level below grade. The building serves as a primary care clinic providing serves such as preventative care, routine examinations, medical consultation services, and others. The building is primarily occupied between 8:00am - 5:00pm Monday - Friday, with little to no operation at night and on weekends.

Steam and chilled water (CHW) are provided by the central plant. There are no tertiary CHW pumps in the building. All fan coil units (FCUs) using chilled water operate off the pressure of the central loop. Steam is supplied to the building at 50 psig and is used only for HVAC heating; domestic hot water is generated by electric heaters.

There are (2) steam to hot water (HW) heat exchangers that serve fan coil units and perimeter baseboard. The pair of HXs has a single set of VFD pumps that operate lead/lag to circulate the HW throughout the building. The heat exchangers operate with a hot water supply temperature reset, ranging between 200°F and 140°F at ambient temperatures between 20°F and 60°F. The pump VFDs modulate to maintain a fixed loop differential pressure set-point of 18 psig.

The airside equipment in the building consists primarily of (70) fan coil units serving zones throughout the building. All fan coils are constant volume, have fixed outdoor air sections, and have both a HW heating and CHW cooling coil. They have no economizer mode or relief ductwork that could enable economizer mode and always receive a fixed volume of return air. FCUs range in size from 400 to 1,200 cfm. Perimeter spaces are also equipped with HW baseboards to provide additional heating. There are also (3) HW unit heaters that serve mechanical and storage spaces in the basement level.

There are approximately (8) building exhaust fans, ranging from 1,000 to 2,000 cfm, serving general building exhaust.

Fan coil units are locally controlled through feedback from Johnson digital wall thermostats that are adjustable with at least 8°F of range. The Johnson controllers have been partially integrated with the campus’ Siemens building automation system; however most points are read from the Johnson controller with limited capabilities to adjust temperature set-points or control sequences.




ENERGY USE GRAPHS

ELECTRICITY Figure 19 on the following page shows electricity use for the Benedict for fiscal year (FYs) 11 – 14. It can be seen that electricity use is fairly consistent between FY-11 and FY-12, except with an inexplicable reduction in use beginning in March FY2013 and continuing for all of FY2014. Figure 20 shows the electric use averaged over FYs 2011-2012, which was taken as the utility use baseline for energy model calibrations. FY2013&14 were excluded from the baseline average as their lower usage values were considered to be uncharacteristic of the facility.


Figure 19: Benedict monthly electricity use (kWh) for Fiscal Years 2011 - 2014.

Figure 20: Benedict baseline electricity use (kWh) profile, using averaged monthly data from Fiscal Years 2011 - 2012.

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Benedict Baseline Electric Use

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FY 12

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Baseline (FY11-12)


STEAM Figure 21 shows the monthly steam consumption for FYs 2010, 2011, 2012, and 2014. It can be seen that FY10 and FY11 follow fairly consistent profiles, but that FY12 and FY14 have vastly different profiles. Discussions with facility staff indicated that this is likely due to data that was missing for all or some portion of these years. Also note that steam data is unavailable for FY13. Figure 22 shows the steam use averaged over FYs 2010-2011, which was taken as the utility use baseline for energy model calibrations. All other years were excluded from the baseline average due to their likely inaccuracies due to data issues.


Figure 21: Benedict monthly 50 lb steam energy use (Lbs) for Fiscal Years 2010 - 2014.

Figure 22: Benedict baseline 50 lb steam energy use (Lbs) profile, using averaged monthly data from Fiscal Years 2010 - 2011.

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FY 10

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Benedict Steam Use FY 11 - FY 14

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FY 12

FY 13

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Baseline (FY10-11)


CHILLED WATER Figure 23 on the following page shows the Benedict CHW use from FYs 11 – 14. It can be seen that FY11 and FY12 follow fairly consistent profiles, but that FY13 and FY14 have differing profiles on certain months, possibly due to meter read date or data collection issues. Figure 24 shows the CHW use averaged over FYs 2011-2012, which was taken as the utility use baseline for energy model calibrations. All other years were excluded from the baseline average due to their likely inaccuracies due to data issues. It is noteworthy that the winter CHW consumption is approximately 1,300 ton-days/month, which is approximately 1/2 of the peak summer CHW consumption. Since cooling loads are expected to be very low in the building during the winter months, this may indicate an issue with the calculation for Benedict’s chilled water usage.


Figure 23: Benedict monthly chilled water energy use (ton-days) for Fiscal Years 2011 - 2014.

Figure 24: Benedict baseline chilled water energy use (ton-days) profile, using averaged monthly data from Fiscal Years 2011 - 2012.

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Benedict CHW Use FY 11 - FY 14

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FY 12

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Benedict Baseline CHW Use

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Baseline (FY11-12)


BENCHMARKING

BENCHMARKING SUMMARY TABLE The table on the following page summarizes the annual energy consumption and performance metrics of the facility. This was done to provide a clear representation of the actual site and estimated equivalent source energy consumption for benchmarking and also for evaluation with energy savings opportunities. Energy use data for the fiscal years 2010 – 2012 is shown in the table, along with an average of data from an estimated typical year. Fiscal years 2013 and 2014 were excluded from this table because of one or more months of utility data was missing for those periods.


Energy Use


Performance Ratings










FY10 1,230,290 516,936 5,282 15.8 1.80 53.8 79.44 4.2 9.5 68 0 85 201 162

FY11 1,230,034 516,456 5,000 15.8 1.80 53.8 79.37 4.2 9.4 64 0 80 197 158

FY12 1,253,040 518,544 1,653 16.0 1.83 54.8 79.69 4.2 9.5 21 0 26 156 105

Est. Typ. Year 1,241,537 517,500 5,141 15.9 1.82 54.3 79.53 4.2 9.5 66 0 82 200 161

UMass Medical Center Benedict Building Energy Use Data


Floor


Steam Total

Source Source

CHW

78,087



Energy and cost savings were estimated using an existing eQuest model of the facility originally developed by Andelman & Lelek and modified to reflect current equipment characteristics, schedules, and internal loads. The model used the TMY3 weather file for Worcester, MA and was calibrated against monthly electric, CHW, and steam use for an estimated typical year as determined using the methods described on the benchmarking summary table above. The charts below compare the estimated typical year data and the calibrated eQuest model predicted utility use.

Both electric and steam use were able to be reasonably calibrated to utility data, however there was a major discrepancy with the CHW use for the entire year. It can be seen that the measured CHW use is higher than the eQuest Output by somewhere between 20,000 and 30,000 ton-days each month. We believe that this somewhat consistent offset suggests an issue with the utility data, as interviews with facility staff revealed that this value was not a direct measurement, but rather a calculated value, as the meter serving meter serving benedict also serves different areas on campus.

Figure 25: Benedict building eQuest model electricity use calibration chart. The baseline monthly electricity use utility data is shown in blue and the eQuest model predicted monthly electricity consumption is shown in red.

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ge (

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)

Monthly Electricity Usage - Benedict

UtilityData

eQUESTOutput


Figure 26: Benedict building eQuest model chilled water calibration chart. The baseline monthly chilled water utility data is shown in blue and the eQuest model predicted monthly chilled water energy consumption is shown in red.

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er U

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UtilityData

eQUESTOutput


Figure 27: Benedict building eQuest model steam calibration chart. The baseline monthly steam utility data is shown in blue and the eQuest model predicted monthly steam consumption is shown in red.

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The table below summarizes the annual end-use energy distribution for electricity, CHW, and steam at the facility as calculated by the baseline eQuest model. The pie chart on the following page illustrates the baseline eQuest model’s electricity end use using the figures shown in the table below.


The following parameters were used to model the estimated miscellaneous loads in the Benedict building, based on information gathered during walkthroughs and historical whole-building electricity use:

1. Lobby, Lounge, Corridor, and Stairwell Plug Loads: 0.10 W/ft2

2. Office Plug Loads: 0.80 W/ft2

3. Exam Room Plug Loads: 1.0 W/ft2


1. Exam Room Lighting Power Density: 1.5 W/ft2

2. Conference Room, Lounge, Office Lighting Power Density: 1.0 - 1.3 W/ft2

Table 4: Benedict Building eQuest model’s annual energy end-use for each meter (electricity, steam, and chilled water).

kWh MLb ton-hrs

Area Lighting 616,834 0 0

Task lighting 0 0 0

Misc. Equip. 294,190 880 0


Space Cooling 0 0 137,028



Ventilation Fans 293,958 0 0

Refrigeration 0 0 0

Heat Pump 0 0 0

Hot Water 0 0 0

Exterior 0 0 0

Total 1,214,701 5,187 137,028


End Use


Table 5: Pie chart showing Benedict Building eQuest model’s annual electricity end use breakdown.


ECM-01.01 (B) LIGHTING RETROFIT

MEASURE ECONOMICS SUMMARY ECM # 01.01 (b) Lighting Retrofit


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


57,116 $5,712 0 $0 0 $0 $5,712 110,150 19.3

BASE CASE The lighting consists of 2’ by 4’ three and two lamp 32 Watt T8 fluorescent fixtures, and 2’x2’ three and two lamp 17 Watt fluorescent fixtures. There are also a small number of 13 Watt compact fluorescent (CFL) recessed can fixtures. The lens type on the fixtures is either prismatic or volumetric. The cans do not have a lens.

PROPOSED CASE This measure proposes to upgrade existing lamps and ballasts to newer high efficiency units where applicable. Refer to the Opinion of Probable Cost Table on the following page for a breakdown of proposed equipment types and quantities. We recommend replacing 4’ 32 Watt T8 lamps with high efficiency 28 Watt lamps and NEMA Premium (NP) electronic ballasts. We also recommend replacing CFLs and incandescent floods with LED lamps. The recommendations do not include fixture upgrades or replacement in an effort to present a more effective retrofit approach. Lighting controls such as occupancy sensors are recommended as a separate measure (refer to ECM-02.01 (b)).


ASSUMPTIONS The audit was performed room-by-room on all of floor A (with the exception of areas that were inaccessible), and all of floor 1, and part of the floor 2. Given the consistency on the floor plan between floors one, two and three, and the room size and resulting fixture type and quantity, captured in the audit, the remaining areas of floors two and three were estimated based upon room size and count. A high level walk through of the estimated areas was performed and any differences were captured in the audit data. Occupancy sensing and other lighting controls are


excluded from this measure due to the nature of the spaces served and 24/7 building operation.



B2Q Associates, Inc. Customer: UMass Medical Date: 12/24/2014

100 Burtt Rd. Ste. 212 Address: Benedict Building Estimated By: KK


(978) 208 - 0609


1 3-Audit


Ballast with 3 Lamp 4 foot 28 Watt T8 with NP

Ballast ea 877 $60 $52,620 $0 0 0 $0 $52,620

2 3-Audit


Ballast with 2 Lamp 4 foot 28 Watt T8 with LP

Ballast ea 98 $60 $5,880 $0 0 0 $0 $5,880

3 3-Audit



Ballast ea 1 $60 $60 $0 0 0 $0 $60

4 3-Audit



Ballast. ea 8 $60 $480 $0 0 0 $0 $480

5 3-Audit


(CFL's) with 5 Watt LED's ea 2 $5 $10 $0 0 0 $0 $10

Subtotal $59,050

1 Means







Total $110,150

Opinion of Probable Construction CostECM-5: Lighting Retrofit


Sources


ECM-02.01 (B) INSTALL OCCUPANCY SENSORS

MEASURE ECONOMICS SUMMARY ECM # 02.01 (b) Install Occupancy Sensors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


129,208 $12,921 9,802 $1,176 -293 -$2,926 $11,171 67,100 6.0

BASE CASE There is currently no automated lighting control in place in Benedict. Interviews with facility staff indicated that a significant amount of the lighting in Benedict remains on 24 hours per day, although the building is unoccupied at night and on weekends. According to staff, corridor and other general lighting is generally left on at all times, while some office and exam room lighting is switched off at night at the discretion of the occupants. Based on this anecdotal evidence, it is estimated that approximately 40% of lighting in the building remains on at night and on weekends.

PROPOSED CASE We recommend replacing the existing lighting wall switches with units that are equipped with built-in occupancy sensors to reduce unnecessary lighting run hours and extended lamp life.

ENERGY SAVINGS METHODOLOGY This measure will result in energy savings from a reduction in run hours for the lighting fixtures in the building.

Energy savings were derived from a parametric run of the baseline eQuest model. The eQuest daily lighting schedule was significantly reduced, with unoccupied period lighting power density reduced as shown in Table 6 on the following page. The average ratio of lights on during unoccupied periods was reduced from 40% in the existing case to 10% in the proposed case through the use of occupancy sensors.


Table 6: Summary table of existing and proposed case hourly average zone lighting power density schedule

Time Period

Base

Case

Lighting

Intensity

Schedule

Proposed

Case

Weekday

Lighting

Intensity

Schedule

Proposed

Case

Weekend

Lighting

Intensity

Schedule

12am-1am 60% 10% 10%

1am-2am 60% 10% 10%

2am-3am 60% 10% 10%

3am-4am 60% 10% 10%

4am-5am 60% 10% 10%

5am-6am 60% 10% 10%

6am-7am 80% 80% 10%

7am-8am 90% 90% 10%

9am-10am 100% 100% 10%

10am-11am 100% 100% 10%

11am-12pm 100% 100% 10%

12pm-1pm 100% 100% 10%

1pm-2pm 100% 100% 10%

2pm-3pm 100% 100% 10%

3pm-4pm 100% 100% 10%

4pm-5pm 90% 90% 10%

5pm-6pm 80% 80% 10%

6pm-7pm 70% 70% 10%

7pm-8pm 60% 60% 10%

8pm-9pm 60% 60% 10%

9pm-10pm 60% 60% 10%

10pm-11pm 60% 10% 10%

11pm-12am 60% 10% 10%

eQuest Model Base & Proposed Case

Lighting Intensities (% of full load)


COST ESTIMATE The costs for this measure include the labor & material cost to connect the BAS into the lighting circuit, along with the labor cost for control programming and documentation associated with implementing the new lighting schedule.




(978) 208 - 0609


1 2 Wall Switch Occ Sensors ea 363 $35 $12,705 $150 1 0.5 $27,225 $39,930

3 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $42,330

1 Means







Total $73,700

Opinion of Probable Construction CostECM-02.01 (b): Install Occupancy Sensors


Sources


ECM-04.09 (B)-1 FAN COIL UNIT CONTROLS UPGRADE

MEASURE ECONOMICS SUMMARY ECM # 04.09 (b)-1 FCU Controls Upgrade


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


244,142 $24,414 25,308 $3,037 3,297 $32,972 $60,423 848,600 14.2

ECM-04.09 (B)-1A UNOCCUPIED TEMPERATURE SET-BACKS

MEASURE ECONOMICS SUMMARY ECM # 04.09 (b)-1a Unoccupied Set-backs & Zone Temperature Control


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


116,132 $11,613 25,453 $3,054 2,159 $21,591 $36,258 - -

BASE CASE Based on a review of fan coil unit historical trend data, there are currently only a few zones that set-back to unoccupied zone temperature set-point at night and on weekends when the building is closed. The majority of fan coils were found to run continuously, controlling to a single set-point that did not reset on a schedule, despite the building being completely unoccupied at night and on weekends according to facility staff. Any set-point changes that were observed are due to local adjustments at each FCU’s thermostat by occupants. Space temperature set-points are adjustable by at least +/-4°F at the thermostats according to field investigation and historical trend data review. As a result, zones were observed to control to a variety of set-points ranging from 68°F to 78°F, which may be contributing to additional energy consumption and possible simultaneous heating and cooling between adjacent zones in the core of the building that are open to each other.

PROPOSED CASE We recommend reconfiguring all zone temperature set-points to 70°F heating and 72°F cooling with no more than +/-2°F of adjustment at each local thermostat to reduce energy consumption and limit simultaneous heating and cooling. We also recommend implementing occupancy-based scheduling on the building’s fan coil units. All fan coils would shut down between 7:30pm - 6:30am Monday-Friday and all day on weekends. We propose implementing separate temperature set-back schedules for perimeter and core zones and limiting the setback in perimeter zones to improve recovery time at the start of the occupied period.


In core areas, we propose a implementing an occupied mode schedule of 6:30am - 7:30pm on weekdays with set-backs of 64°F heating and 78°F cooling during unoccupied mode. In perimeter zones, we propose implementing a heating setback of 67°F, as there are known issues with morning warm-up in perimeter zones during the winter.

This measure will involve replacing the existing Johnson fan coil controllers with Siemens controllers and adding new programming to implement the scheduling and set-points described above. All existing wall mounted thermostats will be replaced with programmable thermostats.

ENERGY SAVINGS METHODOLOGY This measure will result in heating and cooling energy savings during the setback periods by reducing the heating or cooling loads on the fan coils and perimeter baseboard. Heating and cooling savings may also be realized by reducing the simultaneous heating and cooling resulting from set-point fighting between adjacent zones.

The energy savings associated with the temperature setbacks were estimated using a parametric run of the baseline eQuest model. For each applicable zone, the “OFF1 Heat Wk”, “OFF1 Cool Wk”, and “Perim Heating WS” parameters were set to reference the proposed schedules described above.

A bin spreadsheet model was used to calculate energy savings associated with establishing global heating and cooling set-points with +/- 2°F of local adjustment. The additional energy used to maintain existing case zone temperature set-points was estimated based on the average difference between the observed set-points and the recommended set-points, as well as fan coil unit design airflow. The savings calculations assume that 25% of FCUs in the building have occupied zone set-points outside the proposed case range of 71-73°F.


ECM-04.09 (B)-1B CLOSE FCU OA DAMPERS DURING UNOCCUPIED PERIODS

MEASURE ECONOMICS SUMMARY ECM # 04.09 (b)-1b Close FCU OA Dampers During Unoccupied Periods


Electric Cost Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-2,032 -$203 -145 -$17 1,138 $11,381 $11,160 - -

BASE CASE Each FCU in Benedict has a ceiling plenum return and ducted outdoor air section, and maintains a fixed outside air percentage for all hours of operation. A review of ductwork drawings and BAS screenshots indicates that there is no modulating mixed air control, with only a two-position damper on the outside air duct. FCU fans run continuously for all hours of the year despite the building having no occupancy at night and on weekends.

For the purposes of energy modeling, the base case for this measure assumes that ECM-1.1: Unoccupied Temperature Set-backs has been implemented, significantly

PROPOSED CASE We recommend implementing an occupancy based ventilation sequence on the FCUs in Benedict. During unoccupied periods, all twelve outside air dampers will be closed, except during periods when weather conditions would allow outside air to be used to reduce mechanical cooling loads. We recommend keeping outdoor air dampers open during occupied periods to provide sufficient ventilation for the building.

ENERGY SAVINGS METHODOLOGY This measure results in savings by reducing heating and cooling loads on FCUs during unoccupied periods when ventilation is unnecessary.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The FCU minimum outdoor air flow schedule was adjusted so that during unoccupied periods, outdoor air would be reduced to 0%.


ECM-04.09 (B)-1C RETROFIT FCU FANS WITH EC MOTORS

MEASURE ECONOMICS SUMMARY ECM # 04.09 (b)-1c Retrofit FCU Fans with EC Motors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


130,042 $13,004 0 $0 0 $0 $13,004 - -

BASE CASE There are 69 total fan coil units in Benedict, all of which are equipped with permanent split capacitor (PSC) AC fan motors. According to available documentation, all fan-powered boxes are series-type with reheat coils, ranging in airflow capacity from 460 to 2,000 cfm, and feature motors ranging from 58 Watts to 1/2 nominal hp. Fractional horsepower PSC motors such as these typically operate at efficiencies between 20-45% and do not have speed modulation capabilities. Interviews with facility staff revealed that the majority of fans run continuously, as only a few zones in the building have setbacks.

PROPOSED CASE This measure proposes to replace the 69 existing fan powered box Permanent Split Capacitor (PSC) motors with high-efficiency, electronically-commutated (EC) motors. These motors have significantly increased fan efficiency, on the order of 3 – 4 times greater than the PSC motors. Because the EC motors are direct current (DC) motors, they are able to vary their speed based on an input signal of 0 – 10 V without the need for a VFD. We recommend utilizing this capability to increase energy savings beyond what can be achieved from increased fan efficiency alone by controlling fan speed to meet zone temperature in sequence with heating and cooling to minimize fan energy. For example, the fan speed would increase as the difference between the zone temperature and zone temperature set-point increases. These additional energy savings are especially important during low load periods when the fan could be operated at a minimum speed.

This measure would require replacement of each fan motor, the addition of a fan speed (0-10V) control output to each FCU’s controller, and programming changes to accommodate to the new fan motor capabilities and implement a fan speed control sequence.

ENERGY SAVINGS METHODOLOGY This measure results in fan energy savings at all times when the FCUs are in operation, along with additional savings during times when the fan motors are allowed to reduce speed per the temperature control sequence


This measure was modeled using a bin spreadsheet by establishing existing case and proposed case fan load profiles as a function of outdoor air temperature. The existing case model assumed a constant speed fan profile with fixed motor efficiencies based on the motor size and design airflow. The chart below summarizes the efficiency curves used to define each FCU’s motor power consumption.

Figure 28: Chart showing efficiency curves for typical PSC motors.

In the proposed case, a fan speed profile was estimated as a function of outdoor air temperature, assuming average fan speeds would be lowest at outdoor temperatures between 40°F-50°F. Fans were modeled to operate at 100% speed during the warmest outdoor conditions and 90% at the coldest conditions, due to the greater supply air ΔT developed in the heating mode. The chart below summarizes the efficiency curves used to define proposed case FCU EC motor power consumption.

0.00

0.10

0.20

0.30

0.40

0.50

0.60

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Effi

cien

cy (

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fm)

Airflow (cfm)

PSC Motor Efficiency

PSC Motor Size 1

PSC Motor Size 2

PSC Motor Size 3

PSC Motor Size 4


Figure 29: Chart showing efficiency curves for typical EC motors.

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0 200 400 600 800 1,000 1,200 1,400 1,600 1,800 2,000

Effi

cien

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Airflow (cfm)

EC Motor Efficiency

EC Motor Size 1

EC Motor Size 2

EC Motor Size 1 Extrapolation

Poly. (EC Motor Size 1)


ECM-04.09 (B)-1 COST ESTIMATE The costs for this measure include replacement of the existing Johnson FCU controllers, wall thermostats, and necessary programming to implement ECMs 1.1, 1.2, and 1.3. Also included are materials and labor to replace each FCU’s motor with an EC motor.




(978) 208 - 0609


3 3 BAS Control points (1) ea 69 $750 $51,750 $150 1 5 $51,750 $103,5001 3 Modulating Damper Actuators ea 69 $300 $20,700 $150 1 1 $10,350 $31,050

2 3 BAS Control points (1) ea 69 $750 $51,750 $150 1 5 $51,750 $103,500

1 3 EC Motors ea 69 $300 $20,700 $150 1 2 $20,700 $41,400

2 3 New BAS Controllers (3 points) ea 207 $600 $124,200 $150 1 5 $155,250 $279,450

3 3 General Conditions-ceiling ea 69 $50 $3,450 $150 1 2 $20,700 $24,1504 3 As-built ea 69 $0 $0 $150 1 0.5 $5,175 $5,175


Subtotal $593,400

1 Means







Total $848,600


ECM-04.09 (b)-1 Fan Coil Unit Controls Upgrade


Sources


ECM-04.09 (B)-2 HW LOOP DIFFERENTIAL PRESSURE RESET

MEASURE ECONOMICS SUMMARY ECM # 04.09 (b)-2 HW Loop dP Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


7,258 $726 0 $0 -22 -$225 $501 8,100 16.2

BASE CASE The two steam converters in the building, HX-1&2, serve all FCUs and baseboard radiators. The two pumps serving them, HWP-1&2, have VFDs that maintain a constant loop differential pressure set-point of 18 psig.

A review of trend data showed that the building hot water loop operated in May, June, and July with an average temperature differential of 13°F with the pump VFD above minimum speed, indicating a potential opportunity to reduce the loop’s differential pressure set-point.

PROPOSED CASE We recommend implementing an outdoor air temperature reset schedule for the hot water loop differential pressure set-point. The table below summarizes the proposed reset schedule.

Outdoor Air Temperature

Hot Water Loop dP Set-point

30°F 18 psig

60°F 12 psig

The loop would maintain its current set-point of 18 psig at outdoor air temperatures below 30°F, but would linearly reset between 30°F and 60°F down to a minimum set-point of 12 psig to reduce pumping power.

ENERGY SAVINGS METHODOLOGY This measure results in pumping energy savings during lower heating load periods when the differential pressure set-point is reduced below its current set-point.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQUEST model. The run was performed on the “HW Loop” system which serves the FCUs and perimeter baseboard throughout the building. The following parameters were changed as part of the parametric run.


Base Case

HEAD-STPT-CTRL: Fixed

Proposed Case

HEAD-STPT-CTRL: Valve-Reset


COST ESTIMATE The costs for this measure include the labor cost for control programming and documentation associated with sequence changes.




(978) 208 - 0609


1 2 Pressure sensors ea 4 $150 $600 $150 1 4 $2,400 $3,000

3 3 Programming ea 4 $0 $150 1 4 $2,400 $2,400

3 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


5

Subtotal $7,800

1 Means







Total $14,600

Sources


Opinion of Probable Construction CostECM-04.09 (b)-2: HW Loop Differential Pressure Reset


ECM-12.04 (B) INSTALL LOW-E WINDOW FILM

MEASURE ECONOMICS SUMMARY ECM # 12.04 (b) Install Low-E Window Film


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


5,083 $508 5,661 $679 7 $65 $1,253 90,800 72.5

BASE CASE Interviews with facility staff revealed an issue with Southern-facing spaces over-heating in warmer weather due to solar gain. Exterior windows in Benedict are original to the building, constructed in 1992.

PROPOSED CASE We recommend installing low-emissivity (Low-E) window film on the existing glazing in all south & west facing exterior windows in Benedict. The properties of the window film reflect solar radiation, reducing the heat gain in south & west facing spaces during daylight hours, especially during the summer months when radiation intensity is greatest.

ENERGY SAVINGS METHODOLOGY This measure results in energy savings from a reduction in the amount of heat gain through solar exposure. Although this measure results in a reduction of seasonal cooling loads, there is a comparatively small heating energy penalty during colder weather.

Energy savings were derived from a parametric run of the baseline eQuest model. In the proposed case, window construction and performance was reconfigured to model low-e characteristics using the eQuest glass library. Similar center U values were used between the base & proposed case, with a lower solar heat gain coefficient (SHGC) being used on applicable windows in the proposed case. Specifically, the window type was changed from “VE12M Clr/Air/Clr 6” to “VE42M Brz/Air/Clr 6”.

109 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Hospital

COST ESTIMATE The costs for this measure include the labor and material cost to install low-emissivity window film on all exterior windows on the southern and western faces of the Benedict building.




(978) 208 - 0609


1 2 Window Film ea 5400 $10 $54,000 $150 1 0 $0 $54,000

3 ea $0 $150 $0 $0

3 ea $0 $150 $0 $0

4

5

Subtotal $54,000

1 Means







Total $90,800

Sources

Opinion of Probable Construction CostECM-4: Install Low Emissivity Window Film



HOSPITAL EXECUTIVE SUMMARY TABLE

Notes: The cost savings figures in the summary table above assume the following utility rates: $0.10/kWh, $0.12/ton-hour, $10.00/Mlb. Costs and savings for ECM-17.03(c)-2 and 17.03(c)-3 are not included in column totals due to significant overlap with 17.03(c)-1. These three ECMs represent different options for converting the Hospital’s main B-Level and Penthouse AHUs to variable volume.

ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


01.01 (c) Lighting Retrofit 524,392 0 0 $52,439 $1,025,490 19.6

04.02 (c) Comparative Enthalpy Economizer on AHU-1L, 1R, 1T-7T 1,827 168,536 -13 $20,277 $36,850 1.8

04.09 (c)-1 Reconfigure Preheat Circulator Enable Sequence on AHU-1B-6B 3,255 0 0 $326 $11,400 35.0

04.09 (c)-2 Reconfigure AHU-15T/16T Preheat Temperature Control 84 20,813 229 $4,792 $5,800 1.2

04.09 (c)-3 Increase AHU-10T & 11T Minimum Discharge Set-point 187 8,722 70 $1,767 $5,800 3.3

04.09 (c)-4 Hot Water Loop Differential Pressure Reset Schedule 120,840 0 -384 $8,245 $12,000 1.5

04.11 (c) Reconfigure Preheat & Discharge Reset Schedules on AHU-1B-6B 0 281,337 5,468 88,437 $120,700 1.4

04.14 (c) Kitchen Hood Controls 43,857 14,479 2,429 $30,413 $184,800 6.1

17.03 (c)-1 Complete VAV Conversion on AHU-1B-6B & 1T,2T,3T,4T,6T,7T 5,256,107 2,983,462 41,457 $1,298,198 $6,562,276 5.1

17.03 (c)-2 Retrofit Fans with VFDs & Install Branch Duct Dampers 2,429,314 1,165,401 13,359 $516,368 $3,306,679 6.4

17.03 (c)-3 Retrofit Fans with VFDs & Reset Speed vs OAT 3,025,217 3,394,859 43,237 $1,142,278 $929,379 0.8

18.00 (c)-1 Replace Preheat Valves & Actuators on AHU-1B-6B, 1T-7T 0 33,302 400 $7,992 $83,700 10.5

18.00 (c)-2 Lock-out Humidification & Calibrate Return Air %RH Sensors 0 0 2,408 $24,081 $38,200 1.6

18.00 (c)-3 Replace Leaking Preheat Valve on AHU-13T 0 12,333 148 $2,960 $5,000 1.7

18.00 (c)-4 Duct Static Pressure Reset on AHU-1R, 15T/16T 9,665 3,250 14 $1,492 $19,700 13.2

18.00 (c)-5 Adjust AHU-1L Temperature Control 27,088 10,771 36 $4,361 $4,100 0.9

18.00 (c)-6 Optimize Heat Exchanger Reset Schedule -1,566 0 526 $5,099 $12,000 2.4

18.00 (c)-7 Replace Leaking CHW Valve on AHU-11T 0 18,390 223 $4,435 $4,650 1.0

18.00 (c)-8 Fix Mixed Air Dampers to Improve Economizer -213 72,310 -533 $3,327 $22,500 6.8

21.02 (c) Hospital Solar Hot Water 0 0 644 $6,437 $539,439 83.8

5,985,524 3,627,705 53,120 $1,565,077 $8,694,405 5.6TOTAL



The hospital building on the UMMC campus was constructed in 1970, is approximately 700,000 ft2, and stands 10 stories tall, 2 of which are subgrade. The facility houses 417 licensed acute care beds, and contains bone marrow transplant, catheterization, radiation therapy, and neurology departments, among others, and also features a Level 1 trauma center. The building has a full service kitchen and cafeteria that provides three meals per day to patients, employees, and visitors. Most areas of the facility are occupied 24/7.

Steam is supplied at approximately 50 psig, which is converted at (7) steam to hot water (HW) heat exchangers (HXs) to serve AHU preheat coils, fan coil units, reheat coils, and induction units. Each HX has a set of pumps that operate in a lead/lag sequence to circulate the HW throughout the building. The majority of the main HW pumps are equipped with VFDs. Domestic HW is generated via HXs and is stored in (2) 900 gallon tanks.

There are approximately 30 air handling units (AHUs) throughout the building. There are (7) AHUs located in the basement that serve B-Level through Level 2. These constant volume AHUs are typically rated at between 45,000 and 60,000 cfm. Outside air supplied to these units from an intake at the penthouse level via a large shaft that is pressurized using a booster fan. Each AHU is equipped with a dedicated preheat coil circulator for freeze protection and to maintain design flow through the coil. The majority of AHUs serve terminal reheat coils.

There are 15 AHUs located in the tower penthouse that serve the Levels 3 - 8, two are used exclusively as backup units. These primarily serve constant volume or variable volume boxes with HW reheat coils, except for AHU-5T which provides primary ventilation air for the induction units on floors 3 – 8. AHUs-1T – 7T supply approximately 35,000 – 65,000 CFM depending on the unit and are all equipped with dedicated circulators on both the HW preheat coils and CHW cooling coils. AHUs-9T – 16T are smaller units that serve the Bone Marrow Transplant Unit (BMTU) on the 8th Floor. Only AHUs-7T, 15T, & 16T are equipped with VFDs. In addition to the major AHUs, there are also (5) H&V units that serve mechanical spaces and (3) Liebert CRAC units totaling 36 tons.

There are approximately (40) building exhaust fans, serving isolation rooms, lab fume hoods, operating rooms, general exhaust, and kitchen exhaust hoods.

Hospital HVAC is primarily controlled by the Siemens BAS, which was recently upgraded. Some recently upgrade terminal devices are controlled by the Automated Logic building automation system that primarily controls equipment in the School building.

For details on the Hospital’s lighting systems, refer to ECM-16’s existing case description.



ENERGY USE GRAPHS

ELECTRICITY The top graph below shows electricity use for the hospital for FYs 11 – 14. It can be seen that electricity use is very consistent throughout the year, with slight variations between the years likely due to weather effects. The bottom graph shows the electric use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 30: Hospital monthly electricity use (kWh) for Fiscal Years 2011 - 2014.

Figure 31: Hospital baseline electricity use (kWh) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000


Ele

ctri

c U

se (

kWh

)

Hospital Electric Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000


Ele

ctri

c U

se (

kWh

)

Hospital Baseline Electric Use

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-13)


STEAM The top chart below shows the monthly steam consumption for FYs 11 – 14. It can be seen that FY 11 and FY 14 have a noticeably higher consumption during the winter months, possibly due to a higher amount of heating degree days during these years. The bottom graph shows the steam use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 32: Hospital monthly steam energy use (Lbs) for Fiscal Years 2011 - 2014.

Figure 33: Hospital baseline steam energy use (Lbs) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

0

2,000,000

4,000,000

6,000,000

8,000,000

10,000,000

12,000,000

14,000,000

16,000,000


Ste

am U

se (

lbs)

Hospital Steam Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

2,000,000

4,000,000

6,000,000

8,000,000

10,000,000

12,000,000

14,000,000

16,000,000


Ste

am U

se (

lbs)

Hospital Steam Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-13)


CHILLED WATER The top chart below shows the Hospital CHW use from FYs 11 – 14. It can be seen that CHW use is very consistent from year to year. It is noteworthy that the winter CHW consumption is approximately 20,000 ton-days/month, which is approximately 1/3 of the peak summer CHW consumption. This may indicate an opportunity to improve winter economizer mode and reduce simultaneous heating and cooling. The bottom graph shows the CHW use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 34: Hospital monthly chilled water energy use (ton-days) for Fiscal Years 2011 - 2014.

Figure 35: Hospital baseline chilled water energy use (ton-days) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000


Ch

ille

d W

ate

r U

se (

ton

-day

s)

Hospital CHW Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000


Ch

ille

d W

ate

r U

se (

ton

-day

s)

Hospital Baseline CHW Use

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-13)


BENCHMARKING

BENCHMARKING SUMMARY TABLE The table on the following page summarizes the annual energy consumption and performance metrics by the facility. This was done to provide a clear representation of the actual site energy consumption for benchmarking and also for evaluation with energy savings opportunities. Energy use data for Fiscal year 2011 – 2013 is shown in the table, along with an average of data from the three fiscal years.


Energy Use


Performance Ratings

Performance ratings are provided for electricity in three units of measure: total kWh/ft2, equivalent total kBtu/ft2, and annual average W/ft2. Note that since electric demand utility data was not available for the building, an average demand was calculated based on the building’s annual electricity consumption (kWh) divided by the total number of hours in the year (8,760) and converted to Watts (1000 W/kW). Electricity consumption was converted from units of kWh to kBtu using the following factor: 3.413 kBtu = 1 kWh.









FY11 21,580,813 9,923,424 103,029 30.1 3.4 103 166 8.9 19.8 144 0 180 413 333

FY12 21,652,335 10,433,928 97,894 30.2 3.4 103 175 9.3 20.8 137 0 171 414 327

FY13 22,434,606 10,240,224 96,127 31.3 3.6 107 171 9.1 20.4 134 0 168 412 326

3 Year Avg. 21,889,251 10,199,192 99,017 30.5 3.5 104 171 9.1 20.3 138 0 173 413 328

Source

Electricity

716,558

PERFORMANCE RATINGS

UMass Medical Center Hospital Building Energy Use Data

BLDG INFO ENERGY USE

Floor

AreaFiscal Year Electricity CHW 50# Steam

Steam TotalCHW

Source



Energy and cost savings were estimated using an existing eQuest model of the facility originally developed by Andelman & Lelek and modified to reflect current equipment characteristics, schedules, and internal loads. The model used the TMY3 weather file for Worcester, MA and was calibrated against monthly electricity use over a three year period from July 2010 – July 2013. The model was also calibrated for chilled water and steam use using monthly data obtained from the UMass central plant staff. The charts below compare the actual monthly utility use averaged over FY2011-2013 and the calibrated eQuest model predicted utility use.

It can be seen that electric, CHW, and steam use were all able to be calibrated well.

Figure 36: Hospital building eQuest model electricity use calibration chart. The baseline monthly electricity use utility data is shown in blue and the eQuest model predicted monthly electricity consumption is shown in red.

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

Ele

ctri

city

Usa

ge (

kWh

)

Monthly Electricity Usage

UtilityData

eQUESTOutput


Figure 37: Hospital building eQuest model chilled water calibration chart. The baseline monthly chilled water utility data is shown in blue and the eQuest model predicted monthly chilled water energy consumption is shown in red.

Figure 38: Hospital building eQuest model steam calibration chart. The baseline monthly steam utility data is shown in blue and the eQuest model predicted monthly steam consumption is shown in red.

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

Ch

ille

d W

ate

r U

sage

(to

n-h

r)

Monthly Chilled Water Usage

UtilityData

eQUESTOutput

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

Ste

am U

sage

(M

lb)

Monthly Steam Usage

UtilityData

eQUESTOutput


Table 7 on the following page summarizes the annual end-use energy distribution for electricity, CHW and steam at the facility as calculated by the baseline eQuest model. The pie chart on the following page illustrates the baseline eQuest model’s electricity end use using the figures shown in the table.


The following parameters were used to model the estimated miscellaneous loads in the Hospital building, based on information gathered during walkthroughs and historical whole-building electricity use:

1. Lobby, Café, and Corridor Plug Loads: 0.10 W/ft2


3. Patient Room, Clinic, and ER Patient Area Plug Loads: 1.0 W/ft2

4. Laboratory, MRI, ICU, and Surgery Plug Loads: 3.0 W/ft2

5. Kitchen Plug Loads: 10.0 W/ft2


1. Patient Room Lighting Power Density: 0.70 W/ft2

2. Corridor Lighting Power Density: 1.0 W/ft2

3. Office Lighting Power Density: 1.1 W/ft2

4. Kitchen Lighting Power Density: 1.2 W/ft2

5. Laboratory and Exam Room Lighting Power Density: 1.4 - 1.5 W/ft2

6. Surgery and ICU Lighting Power Density 2.2 W/ft2


Table 7: Hospital Building eQuest model’s annual energy end-use for each meter (electricity, steam, and chilled water).

Figure 39: Pie chart showing Hospital Building eQuest model’s annual electricity end use breakdown.

kWh MLb ton-hrs

Area Lighting 4,368,300 0 0

Task lighting 0 0 0

Misc. Equip. 4,625,527 9,244 0


Space Cooling 0 0 9,550,203




Refrigeration 0 0 0

Heat Pump 0 0 0

Hot Water 0 0 0

Exterior 0 0 0

Total 22,454,161 110,267 9,550,203

Baseline

Annual Energy By End Use


ECM-01.01 (C) LIGHTING RETROFIT

MEASURE ECONOMICS SUMMARY ECM # 01.01 (c) Lighting Retrofit


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


524,392 $52,439 0 $0 0 $0 $52,439 $1,025,490 19.6

BASE CASE The lighting in the hospital was updated between 1996 and 1998 and primarily consists of one, two, and four lamp fluorescent fixtures, containing 4’ 32 Watt T8 lamps with normal and low power ballasts. There are also a limited number of one, two, and three lamp 17 Watt T8 fluorescents, and 18 Watt compact fluorescents (CFLs) scattered throughout that facility. The halls, staff areas/stations and patient rooms on floors three through seven for the most part, remain unchanged from the fixtures and lamps that were installed as a part of the 1996-1998 lighting project.

UMass recently upgraded lighting in three buildings on campus, with the entire project consisting of approximately 10,000 28 Watt T8 lamps. An estimated 5,300 of these were dedicated to the Hospital. UMass staff ‘relamped’ a large portion of the halls, entryways, and common area fluorescent fixtures that remain on during all hours of the year.

PROPOSED CASE This measure proposes to upgrade existing lamps and ballasts to newer high efficiency units where applicable. Refer to the Opinion of Probable Cost Table on the following page for a breakdown of proposed equipment types and quantities. We recommend replacing 4’ 32 Watt T8 lamps with high efficiency 28 Watt lamps and NEMA Premium (NP) electronic ballasts. We also recommend replacing CFLs and incandescent floods with LED lamps. The recommendations do not include fixture upgrades or replacement in an effort to present a more effective retrofit approach. Lighting controls such as occupancy sensors are not recommended due to the nature of the spaces and the 24/7 building operation.

The recent upgrade project described in the Base Case decreased the overall number of 4’ fluorescent fixtures that are candidates for retrofits as a part of this ECM. The impact of the upgrades are included in the in the Measure Economics summary table above and the Cost Estimate table.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in electricity use by installing high efficiency fluorescent lamps and more efficient ballasts. The energy savings calculations make estimates


for annual run hours of each fixture based on information obtained from facilities and maintenance staff. The calculations assume that run hours remain the same in the proposed case.

ASSUMPTIONS A room by room audit of floors one, two, and three were performed. There were significant changes to floors one and two from what was on the Noresco audit. Areas that were eliminated or reconfigured were captured in the audit. Because floors three through seven consist primarily of staff stations, and single and double size patient rooms, and remain unchanged from the lighting work done 1996/1998, the recommendations and calculations have been done based upon a lighting update done to one floor (floor three) and extrapolated through the remaining five patient floors. Occupancy sensing and other lighting controls are excluded from this measure due to the nature of the spaces served and 24/7 building operation.

COST ESTIMATE The cost estimate for this measure is shown in the table on the following page. The labor cost for the recommended retrofits are included in the material costs below.



100 Burtt Rd. Ste. 212 Address: Hospital Building Estimated By: KK


(978) 208 - 0609


1 3-Audit



Ballast ea 3370 $55 $185,350 $0 0 0 $0 $185,350

2 3-Audit



Ballast ea 1523 $45 $68,535 $0 0 0 $0 $68,535

3 3-Audit

Retrofit - 2 Lamp 4 foot 32 Watt T8 with LP


Ballast ea 2839 $60 $170,340 $0 0 0 $0 $170,340

4 3-Audit

Retrofit - 1 Lamp 2 foot 17 watt T8 with NP

Ballast with 1 Lamp 2 foot 17 watt T8 with LP

Ballast ea 670 $45 $30,150 $0 0 0 $0 $30,150

5 3-Audit



Ballast ea 1412 $65 $91,780 $0 0 0 $0 $91,780

6 3-Audit



Ballast ea 37 $55 $2,035 $0 0 0 $0 $2,035







(978) 208 - 0609


7 3-Audit

Retrofit - 1 Lamp 3 Foot 25 Watt T8 with NP

Ballast with 1 Lamp 3 Foot 15 Watt T8 with LP

Ballast ea 2 $45 $90 $0 0 0 $0 $90

8 3-Audit

Retrofit 3 Lamp 2 Foot 17 Watt T8 with NP

Ballast with 3 Lamp 2 Foot 17 Watt T8 with NP

Ballast ea 40 $60 $2,400 $0 0 0 $0 $2,400

9 3-Audit


(CFL's) with 5 Watt LED's ea 102 $5 $510 $0 0 0 $0 $510

10 3 Audit



11 3 Audit

Replace 2 Lamp 13 Watt Compact Florescents

fixtures with 9 Watt LED's ea 188 $5 $940 $0 0 0 $0 $940

Subtotal $551,190

1 Means







Total $1,025,490



Sources


ECM-04.02 (C) COMPARATIVE ENTHALPY ECONOMIZER ON AHU-1L,1R,1T-7T

MEASURE ECONOMICS SUMMARY ECM # 04.02 (c) Comparative Enthalpy Economizer on AHU-1L, 1R, 1T-7T


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


1,827 $183 168,536 $20,224 -13 -$130 $20,277 $36,850 1.8

BASE CASE AHU-1L is a single zone variable volume AHU that serves the Hospital’s Remillard Lobby. The unit has a 10,000 cfm design supply airflow, a 15 hp supply fan motor, 3 hp return fan motor, and a single point economizer with a 50°F high limit lockout. This relatively low lockout temperature significantly limits the number of hours during the year which the economizer can operate.

AHU-1R is a multi-zone variable volume AHU that serves the Hospital’s new 2nd floor Catheterization Lab. The unit has a 32,000 cfm design supply airflow, a 60 hp supply fan motor, 30 hp return fan motor, and comparative economizer with a 0°F offset between outdoor and return air temperature.

AHU-1T, 2T, 3T, 4T, 5T, 6T, and 7T are multi-zone constant volume AHUs that serve Level 3 through Level 8 of the Hospital. Each AHU features an economizer sequence with a 70°F outdoor air lock-out.

PROPOSED CASE We propose implementing a comparative enthalpy economizer on AHU-1L, AHU-1R, and the seven penthouse AHUs identified in the existing case with a 0 Btu/lb offset so that the sequence is enabled whenever the outdoor air enthalpy is less than the return air enthalpy. This measure will include the installation of a new return air relative humidity sensor on AHU-1L and AHU-1R.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in mechanical cooling energy during periods when the outdoor air enthalpy is less than each AHU’s return air enthalpy, but economizer was not enabled in the existing case. In addition, the existing comparative economizer on AHU-1R using temperature only causes the sequence to be active during periods when the outdoor temperature may be less than the return, but the enthalpy may be greater, resulting in excess total mechanical cooling energy.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on hAHU1R and hAHU1L and changed the following parameters:

hAHU1R Base Case

OA-CONTROL: Dual Temperature

DUAL-TEMP-DT: 0°F

DUAL-ENTHALPY-DH: n/a Proposed Case

OA-CONTROL: OA Temperature

DUAL-TEMP-DT: n/a

DUAL-TEMP-DT: 0 Btu/lb hAHU1L

Base Case

OA-CONTROL: Outdoor Temperature

DRYBULB-LIMIT: 50°F


OA-CONTROL: Dual Enthalpy

DRYBULB-LIMIT: n/a

DUAL-ENTHALPY-DH: 0 Btu/lb hAHU1T,2T,3T,4T,5T,6T, and 7T

Base Case

OA-CONTROL: Outdoor Temperature

DRYBULB-LIMIT: 70°F



DRYBULB-LIMIT: n/a

DUAL-ENTHALPY-DH: 0 Btu/lb



B2Q Associates, Inc. Customer: Umass Medical Date: 12/24/2014

100 Burtt Rd. Ste. 212 Address: Hospital Building Estimated By: JAB


(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 6 $900 $900


3 3 Humidity Sensor ea 9 $750 $6,750 $150 1 2 $2,700 $9,450

4 3 BAS Programming ea 9 $0 $150 1 6 $8,100 $8,100

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $20,250

1 Means







Total $36,850

Opinion of Probable Construction CostECM-04.02 (c): Comparative Enthalpy Economizer on AHU-1L, AHU-1R, and AHU-1T-7T


Sources


ECM-04.09 (C)-1 RECONFIGURE PREHEAT CIRCULATOR ENABLE

SEQUENCE

MEASURE ECONOMICS SUMMARY ECM # 04.09 (c)-1 Reconfigure Preheat Circulator Enable Sequence on AHU-1B-6B


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


3,255 $326 0 $0 0 $0 $326 $11,400 35.0

BASE CASE AHU 1B – 6B each have a dedicated preheat coil circulator pump that is primarily used for freeze protection and to maintain the necessary flow through the coil. The design info for each circulator is shown in the chart below.

All six pumps are enabled based on outdoor air temperature, turning on when below 50°F. See Figure 40 on Page 134 for a trend screenshot showing this sequence in more detail. This method of control is intended to ensure the pumps are circulating hot water through the coil when the unit is calling for heating.

Historical trend logs and the controls sequence of operation indicate that the circulators are enabled at outdoor air temperatures less than 50°F. However, it was observed that all six circulators turned on more than a dozen times in May 2014, despite there being no call for heating. This example represents instances when the pumps are running and consuming energy unnecessarily.

Unit

Name

Pump

Quantity

Design

Flow

Design

HeadVFD

Average

Speed

Pump

Motor

Rating

Shaft

Power

Input

Power

gpm ft WC hp bhp kW

AHU-1B 1 256 25 Yes 25% 5 0.1 0.1

AHU-2B 1 256 25 Yes 25% 5 0.1 0.1

AHU-3B 1 220 35 Yes 25% 5 0.1 0.1

AHU-4B 1 208 25 Yes 25% 5 0.1 0.1

AHU-5B 1 174 25 Yes 25% 5 0.1 0.0

AHU-6B 1 208 25 No 100% 5 2.0 1.7

Totals 6 30 2.4 2.0

HW Circulator Pump Information


PROPOSED CASE We recommend modifying the existing preheat circulator sequence of operation by enabling pumps for operation based on heating load instead of outdoor air temperature. In the proposed case, pumps would start and run when the discharge or preheat discharge air temperature control loops call for heating. Once enabled, the pump variable speed drives would operate according to the existing control sequence. This measure will reduce the energy consumption of the circulators without have adverse impacts on equipment freeze protection.

ENERGY SAVINGS METHODOLOGY This measure will result in energy savings due to a reduction in run hours of the dedicated AHU heating coil circulator pumps. Savings were calculated using an 8,760 hour spreadsheet using TMY3 (Typical Meteorological Year 3) weather data for Worcester, MA. Energy savings are derived from the reduction in preheat circulator run hours during periods when the outdoor air temperature is below 50°F but preheat is not necessary to meet discharge air temperature set-points.

In the base case model, pump run hours were limited to when the outdoor air temperature was below 50°F. The proposed case model recalculated pump run hours, limiting operation only to periods when the outdoor air temperature was low enough to require the heating coil valve to be open. This outdoor air temperature threshold was different for each AHU due to differences in minimum outdoor air ratios, observed discharge air temperatures, and return air temperatures.


Figure 40: The trend scatterplot below shows the preheat circulator VFD speed (Hz) for AHU-2B versus outdoor air temperature (°F). The pattern is typical of the B-Level AHUs and shows that the pumps are enabled at outdoor air temperatures below 50°F. The chart also shows that the VFD speed is directly proportional to outdoor air temperature.


COST ESTIMATE The following estimate was developed using estimates for programming labor. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable.




(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $6,000

1 Means







Total $11,400

Opinion of Probable Construction CostECM-04.09 (c)-1: Reconfigure Preheat Circulator Enable Sequence on AHU-1B-6B


Sources


ECM-04.09 (C)-2 RECONFIGURE AHU-15T/16T PREHEAT

TEMPERATURE CONTROL

MEASURE ECONOMICS SUMMARY ECM # 04.09 (c)-2 Reconfigure AHU-15T/16T Preheat Temperature Control


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


84 $8 20,813 $2,498 229 $2,286 $4,792 $5,800 1.2

BASE CASE AHU-15T and AHU-16T have a separate preheat coil discharge set-point and discharge air set-point. The preheat discharge set-point is fixed at 55°F and the discharge air set-point of 52°F, which was found to result in unnecessary simultaneous heating and cooling during the winter and shoulder seasons. Figure 41 on Page 138 illustrates this issue on AHU-15T.

PROPOSED CASE We recommend eliminating the preheat coil’s discharge set-point and controlling the mixed air dampers, preheat coil, and chilled water coil in sequence to the discharge air temperature set-point. For freeze protection, we propose implementing a 45°F preheat discharge air low-limit that would be maintained at all times.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in simultaneous heating and cooling that will occur when the preheat and chilled water coils properly control to the same set-point.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQUEST model. The run was performed on AHU-15T/16T and changed the following parameters:

Base Case

PREHEAT-SOURCE: Hot Water Loop

HEAT-SOURCE: Not Installed

PREHEAT-CAPACITY: Autosized

PREHEAT-T : 55°F

COOL-CONTROL: Constant

COOL-SET-T: 52°F


Proposed Case

PREHEAT-SOURCE: Not Installed

HEAT-SOURCE: Hot Water Loop

PREHEAT-T : n/a


COOL-SET-T: 52°F


Figure 41: The trend screenshot of AHU-15T below shows that the preheat leaving air temperature (RED) is controlled to a 55°F minimum set-point while the discharge air temperature (ORANGE) is controlled to a fixed set-point (DARK BLUE) of 52°F. The trend also shows that the preheat valve (LIGHT BLUE) is opening to maintain the preheat set-point and that the mixed air temperature (PINK) is lower than the preheat temperature, confirming preheat is enabled.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $3,000

1 Means







Total $5,800


Sources

Opinion of Probable Construction CostECM-04.09 (c)-2: Reconfigure AHU-15T/16T Preheat Temperature Control


ECM-04.09 (C)-3 INCREASE AHU-10T & 11T MINIMUM DISCHARGE

SET-POINT

MEASURE ECONOMICS SUMMARY ECM # 04.09 (c)-3 Increase AHU-10T & 11T Minimum Discharge Set-point


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


187 $19 8,722 $1,047 70 $701 $1,767 $5,800 3.3

BASE CASE AHU-10T and AHU-11T are constant volume 100% outdoor air make-up air units that serve the 8th Floor Bone Marrow Transplant Unit (BMTU). AHU-10T serves four rooms, each with a zone reheat, and AHU-11T serves three rooms, each with a zone reheat. Both AHUs have discharge air temperature set-points that reset linearly based on outdoor air temperature according to the following schedule:


Discharge Temperature Set-point

0°F 75°F

55°F 55°F

The original sequence of operation describes a minimum discharge air set-point of 57°F; however, the observed minimum discharge set-point was 55°F. Historical trend data showed that zone reheats were active for the majority of the summer, suggesting that the minimum discharge air temperature may be too low for the zone loads.

PROPOSED CASE We propose increasing the minimum discharge air set-point in the outdoor air reset schedule from 55°F to 57°F to reduce reheat during the summer months and shoulder seasons. The proposed outdoor air reset is shown in the table below:


Discharge Temperature Set-point

0°F 75°F

55°F 57°F

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in mechanical cooling energy and reheat primarily during periods when the outdoor air temperature is greater than 55°F.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQUEST model. The run was performed on AHU-15T/16T and changed the following parameters:

Base Case

COOL-RESET-SCH: DAT Reset 2 Sch

o Outdoor Drybulb High Temperature: 55°F

o Outdoor Drybulb Low Temperature: 0°

o Supply Leaving Temp @ Outdoor Low: 75°F

o Supply Leaving Temp @ Outdoor High: 55°F

Proposed Case

COOL-RESET-SCH: ECM#3.2 DAT Reset Sch


o Outdoor Drybulb Low Temperature: 0°








(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $3,000

1 Means







Total $5,800

Opinion of Probable Construction CostECM-04.09 (c)-3: Increase AHU-10T & 11T Minimum Discharge Set-point


Sources


ECM-04.09 (C)-4 HOT WATER LOOP DIFFERENTIAL PRESSURE RESET

SCHEDULE

MEASURE ECONOMICS SUMMARY ECM # 04.09 (c)-4 Hot Water Loop Differential Pressure Reset Schedule


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


120,840 $12,084 0 $0 -384 -$3,839 $8,245 $12,000 1.5

BASE CASE Historical trend data shows that the loop differential pressure set-point on HX-1, 2, 3, 4, and 7 is fixed at 15 psig. Figure 42 on Page 145 shows an example loop differential pressure trend and the corresponding pump VFD speed. During the summer months, these loops may be over pumped by maintaining a differential set-point that is greater than necessary to maintain flow at the further coils.

PROPOSED CASE We recommend implementing a loop differential pressure reset as a function of outdoor air temperature, using the parameters defined in the table below.

Outdoor Temperature

Loop dP Set-point

°F psig

30°F 15

70°F 10

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in pumping power needed to maintain a lower loop differential pressure set-point when the system is at part load.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the “HW Loop” system which models HX-1, 2, 3, 4, and 7. The following parameters were changed as part of the parametric run.

Base Case


Proposed Case


Figure 42: The trend screenshot below shows the VFD speeds (BLUE, ORANGE) for the two pumps serving HX-1 and the loop’s differential pressure (RED). The differential pressure is approximately constant throughout the year, ranging between 13-15 psig.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $6,600

1 Means







Total $12,000

Opinion of Probable Construction CostECM-04.09 (c)-4: Hot Water Loop Differential Pressure Reset Schedule on HX-1-4 and HX-7


Sources


ECM-04.11 (C) RECONFIGURE PREHEAT & DISCHARGE AIR RESET

SCHEDULES ON AHU-1B-6B

MEASURE ECONOMICS SUMMARY ECM # 04.11 (c) Reconfigure Preheat & Discharge Reset Schedules on AHU-1B-6B


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 281,337 $33,760 5,468 $54,676 $88,437 $120,700 1.4

BASE CASE AHU-2B—6B are currently equipped with separate preheat coil discharge air and supply air reset schedules that can result in simultaneous heating and cooling during periods when the outdoor air temperature is less than 50°F. The set-points reset based on outdoor air temperature and are shown in the table below. Figure 43 below shows the reset in graphical form.

Preheat Discharge Discharge

OAT DAT-SP OAT DAT-SP

10°F 65°F 5°F 62°F

42°F 55°F 55°F 55°F

Figure 43: B-Level AHU preheat- and discharge-air temperature resets as a function of outdoor air temperature.

50

52

54

56

58

60

62

64

66

68

70

0 10 20 30 40 50 60 70 80

Dis

char

ge S

et-

po

int

(°F)

Outdoor Air Temperature (°F)

B-LEVEL AHU Temperature Resets

Discharge Air Temperature Set-point Preheat Discharge Set-point


Figure 43 above includes a dashed blue line that is offset from the discharge air temperature set-point by 2°F to indicate the approximate temperature that the chilled water coil must meet in order for the discharge set-point to be satisfied as a result of heat added by the supply fan and motor. Based on the measured fan motor input power, the motor efficiency, estimated fan efficiency, and design airflow of the AHU, the heat generated at the fan was calculated to be 2.02°.

Note that although AHU-1B should be configured with the same set-point resets as the other B-Level AHUs, historical trend data showed that the discharge air temperature set-point on this AHU remained fixed throughout the year at 53°F. However, the preheat leaving air set-point reset was found to be the same as other AHUs.

The chart shows that when each AHU’s mixed air temperature is lower than the preheat discharge air temperature set-point, simultaneous heating and cooling becomes an issue due to the difference in discharge set-points. For example, at an outdoor air temperature of 20°F, AHU-3B’s mixed air temperature will be approximately 53°F at 36% outdoor air. The preheat coil will first increase the temperature of the supply air to 62°F to meet its set-point. The chilled water coil will then lower the air temperature to approximately 58°F in order to meet the 60°F discharge air temperature set-point. Although this scenario uses approximately 566 kBtu/hr of heating energy and 21 tons of cooling, the sequence could be reconfigured to eliminate virtually all of the consumption in this example.

The Hospital’s Facilities and Maintenance staff have indicated that the AHU preheat and discharge air resets have been configured in this way to prevent freezestat trips and the associated equipment shutdowns, as well as a precaution against coil freezing. One of the primary reasons that freezestat trips were an issue before implementing the separate preheat reset was the lack of sufficient mixing of the outdoor and return air. Outdoor air enters each mixing plenum from a vertical set of louvers on the side along the back of the unit while return air enters from the top of the unit, which allows cold outdoor air to quickly sink to the floor of the AHU without properly mixing with the return. During the winter, this could result in a freezestat trip if cool air is not evenly preheated across the coil.

PROPOSED CASE We recommend installing air mixers in each of the AHU mixed air plenums to help equalize the temperature of the air leaving the primary filter bank and entering the preheat coil and freezestat. We also propose a revision to the preheat discharge air reset so that the preheat set-point is always 2°F lower than the effective discharge air temperature reset in order to account for fan and motor heat gain. The table below shows the proposed preheat and discharge air resets as a function of outdoor air.

Preheat Discharge Discharge

OAT DAT-SP OAT DAT-SP

5°F 60°F 5°F 62°F

55°F 53°F 55°F 55°F


ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in simultaneous heating and cooling that was observed to occur as a result of the differences in the preheat coil leaving air set-point and discharge air set-point resets.

The energy savings associated with this measure were estimated using a bin-type spreadsheet model that calculated the average magnitude of unnecessary preheat energy (Btu/hr) used by all AHUs at different outdoor air conditions. This energy was calculated using the following equation:

𝑄 [𝐵𝑡𝑢

ℎ𝑟] = 1.08 ∗ 𝑆𝑢𝑝𝑝𝑙𝑦 𝐴𝑖𝑟𝑓𝑙𝑜𝑤 ∗ (𝑃𝑅𝐻𝑇𝑆𝑃 − ( 𝐷𝐴𝑇𝑆𝑃 − 𝛥𝑇𝐹𝑎𝑛,𝑚𝑜𝑡𝑜𝑟))

Where ‘Supply Airflow’ is equal to the total supply airflow of all seven AHUs included in this measure and ‘ΔTFan,Motor’ is equal to the average temperature rise across the fan and motor as a result of mechanical and electrical losses to the airstream.

Hot water energy savings were converted to steam savings assuming a steam heating value of 1,000 Btu/lb and a 97% conversion and distribution efficiency.

The model assumed that the amount of wasted chilled water energy was equal to the amount of unnecessary preheat energy, since minimal latent cooling would occur at the cooler outdoor air temperatures that this measure focuses on.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 3 Air Blenders ea 6 $5,000 $30,000 $150 2 16 $28,800 $58,800

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $64,800

1 Means







Total $120,700

Opinion of Probable Construction CostECM-04.11 (c): Reconfigure Preheat & Discharge Air Reset Schedules on AHU-1B-6B


Sources


ECM-04.14 (C) KITCHEN HOOD CONTROLS

MEASURE ECONOMICS SUMMARY ECM # 04.14 (c) Kitchen Hood Controls


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


43,857 $4,386 14,479 $1,737 2,429 $24,290 $30,413 $184,800 6.1

BASE CASE There are 4 kitchen exhaust fans which serve the exhaust hoods over the various appliances. The kitchen provides breakfast, lunch and dinner and operates from 5 AM to 7PM, 365 days per year. Make-up air to the kitchen/cafeteria is supplied by AHU-2-B which has a total air supply of 59,700 CFM, which brings in ~23,000 CFM of outside air. The existing fans run constant speed, maintaining a fixed air flow during all run hours. The existing fans already have VFD’s controlling the motor speeds, which were set during the balancing effort.

Fan Serves Nameplate Calculated Input

Power Balanced Airflow

Tag Equipment hp kW cfm

KEF-1 Grease Hood Level A 10.0 7.3 7,381

KEF-2 Kettle Hood Level A 7.5 5.5 7,076

KEF-3 Grease Hood Level 1 3.0 2.4 2,365

KEF-4 Dishwasher Level 1 7.5 5.5 7,584

TOTALS 28.0 20.7 24,406

PROPOSED CASE The proposed case is to install new control systems utilizing smoke or infrared cooking sensors and temperature sensors in all the kitchen hoods and connect the controller to the existing VFDs. KEF-3 serves 2 grease hoods and KEF-1, 2- 4 each serve single hoods. The control systems will operate the exhaust fan motor VFDs at a low of 50% speed until heat is generated from cooking equipment or smoke/cooking is sensed. The VFD will ramp to full speed immediately when smoke/cooking is sensed, and will ramp up more slowly if only a temperature rise is detected (e.g. from ovens under the hood). Similarly, the fan VFDs will ramp down when there is no cooking activity. The kitchen exhaust fan controllers will be tied into the existing Siemens building control system for monitoring and alarm purposes. The installation should include an interlock with both the hood and building fire prevention system. It should also include a manual override to instantly ramp the VFDs to full exhaust air flow and the control system should revert to full flow in the event of a failure. To help maintain the proper air balance in the space a new damper will be installed in the supply air ductwork that serves the


kitchen/cafeteria. Also a new space differential pressure sensor should be installed to monitor the kitchen air pressure relative to the surrounding spaces; feedback from this sensor will be used to regulate the supply air damper. The damper actuator and sensor will be tied into the existing Siemens control system.

ENERGY SAVINGS METHODOLOGY The energy savings for this measure were calculated using time of day profiles combined with a temperature-based bin model. The bin model uses 5oF temperature bins and TMY3 weather data for Boston, MA. The base case is modeled with the exhaust fans operating 5,110 hours per year. The kitchen MAU scheduling was included in Phase 1 EEM 2: DDC Control of AHUs and therefore it is assumed to be implemented for the base case. In the proposed case, it is assumed that the BAS will also turn the exhaust fans off at the same time as the MAU. The assumed flow profile is shown in the table below. The average fan speed is assumed to increase to 100% during periods of high cooking for the three meals each day. The average fan speed is assumed to be reduced to 75% in the hours before and after each meal to account for the variability in cooking start and end times for each meal.

Hour of

Day

Fan VFD

Speed (%)

Hour of

Day

Fan VFD

Speed (%)

1 0% 13 100%

2 0% 14 75%

3 0% 15 50%

4 0% 16 50%

5 50% 17 100%

6 75% 18 100%

7 100% 19 50%

8 100% 20 0%

9 50% 21 0%

10 50% 22 0%

11 50% 23 0%

12 100% 24 0%


COST ESTIMATE The opinion of probable cost for this measure is based on previous vendor quotes for the furnishing and installation of new kitchen hood controls systems. It also includes the cost to interface to the BAS, an allocation for air flow measurements, and commissioning.




(978) 208 - 0609

Total


1 3 Kitchen hood controllers ea 4 $20,000 $80,000 $150 2 16 $19,200 $99,200

2 3 Hood Air Flow Measurements ea 5 $0 $150 1 8 $6,000 $6,000

3 3 New supply air duct damper ea 1 $1,000 $1,000 $150 2 8 $2,400 $3,400

4 3 Siemens monitoring and control points ea 4 $750 $3,000 $150 1 5 $3,000 $6,000

5 4 Duct Air Flow Measurements ea 1 $0 $150 2 8 $2,400 $2,400

6 3 As-Builts ea 1 $0 $150 1 16 $2,400 $2,400


8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $124,200

1 Means







Total $184,800

Opinion of Probable Construction CostECM-04.14 (c): Kitchen Exhaust Hood Controls


Sources


Note: The three (3) following measures are presented as separate options for reducing the energy consumption of the Hospital’s constant volume air handling units. The costs and savings estimates for these measures overlap and as a result, only the cost and savings for the first option (ECM-17.03 (c)-1) is included in building’s executive summary totals.

ECM-17.03 (C)-1 COMPLETE VAV CONVERSION AHU-1B-6B, 1T,2T,3T,4T,6T,7T

MEASURE ECONOMICS SUMMARY

BASE CASE All six major B-Level AHUs (AHU-1B, 2B, 3B, 4B, 5B, and 6B) are constant volume with hot water preheat coils, chilled water cooling coils, steam humidification, and have fixed fractions of outdoor air. Six of the seven total penthouse AHUs (AHU-1T, 2T, 3T, 4T, 6T, and 7T) are also constant volume and feature the same coil configuration as the basement level AHUs, but feature modulating mixed air dampers with a single-point economizer.

The supply fan motor nameplate ratings on the AHUs range from 60 hp up to 125 hp and the return fans on applicable AHUs range from 15 to 50 hp. The table below summarizes key parameters for the AHUs included in this measure. AHUs serve zones via 386 constant volume zone reheats equipped with hot water coils.

AHU-# Total

Supply Supply Fan Return Fan Preheat Capacity CHW Capacity

cfm hp hp MBH tons

AHU-1B 49,560 125 30 3,840 433

AHU-2B 59,740 100 20 3,840 195

AHU-3B 58,240 125 25 3,300 240

AHU-4B 58,240 125 30 3,120 210

AHU-5B 41,750 100 25 2,610 165

AHU-6B 52,680 100 30 3,120 210

AHU-1T 35,600 75 25 2,520 175

AHU-2T 43,530 (2) 50 15 2,700 308

AHU-3T 46,400 75 15 2,520 210

AHU-4T 4,320 75 20 2,880 216

ECM # 17.03 (c)-1

Electric

Energy

Savings

Electric Cost

Savings

CHW

Energy

Savings

CHW Cost

Savings

Steam

Savings

Steam

Cost

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


5,256,107 $525,611 2,983,462 $358,015 41,457 $414,571 $1,298,198 $6,562,276 5.1

Complete VAV Conversion on AHU-1B-6B & 1T,2T,3T,4T,6T,7T


AHU-6T 66,500 125 50 3,420 245

AHU-7T 44,940 125 15 3,780 373

PROPOSED CASE This measure proposes a complete conversion of the twelve (12) AHUs included in the table above from constant volume to variable volume. This would include replacing each AHU’s supply and return fan motor, retrofitting each motor with an 18 pulse VFD, and replacing each zone reheat with a variable volume box and new reheat coil. As part of this measure, the existing terminal device pneumatic controls would be replaced with full DDC controls, which include new digital thermostats, new actuators, flow stations, and controllers. Note that although we have carried costs for replacement of the existing zone reheats with new VAV boxes, a hybrid approach could be taken to potentially reduce capital costs. The existing reheat coil could be re-used with a new valve and actuator and a new VAV box without a coil could be installed upstream to provide flow control to each zone. Each supply fan VFD would be controlled by a new duct static pressure sensor to be located approximately 2/3rds of the way down the duct system, and each return fan VFD would be controlled to track the supply fan VFD speed. VAV boxes would be configured with a proposed average minimum airflow of 50%, varying depending on the air change rate requirements in each individual zone. VAV controls would control space temperature by modulating terminal unit dampers. On a drop in space temperature below the effective heating set-point, the VAV damper would close to maintain the minimum airflow set-point and the reheat valve would open as necessary. On a rise is space temperature above the effective cooling set-point, the reheat valve would remain closed and the damper would modulate to maintain the set-point.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan, mechanical cooling, preheat, and reheat energy that is used to supply conditioned air at constant volume during all hours of the year.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the model systems shown in the table on the following page.


AHU-# BASE CASE PROPOSED CASE

MIN-FLOW-

RATIO FAN EIR f(PLR)

FAN-CONTROL

MIN-FLOW-RATIO

FAN EIR f(PLR)

FAN-CONTROL

AHU-1B 1.00 n/a Constant 0.50 VSD FPLR Variable






AHU-1T 1.00 n/a Constant 0.50 VSD FPLR Variable






COST ESTIMATE The cost estimate on the following page was developed using budget quotes for VFDs and motors replacement, as well as estimates for installation of new VAV boxes, BAS points, programming, TAB, ceiling and duct work, and electrical installation. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable. The cost estimate assumes that sufficient floor space is available in the basement mechanical room to accommodate the proposed 18-pulse VFDs. This assumption should be verified during the schematic design process to determine if sufficient space exists.





(978) 208 - 0609

Total


1 3 As-Builts ea 13 $0 $150 1 16 $31,200 $31,200


3 2 125 hp VFD and Motor ea 5 $16,000 $80,000 $150 2 6 $9,000 $89,000









12 3 Startup/Freight ea 26 $250 $6,500 $150 1 8 $31,200 $37,700


14 3 BAS Control Points ea 1,211 $1,500 $1,816,500 $0 $1,816,500

15 3 VAV Boxes ea 386 $1,500 $579,000 $150 2 4 $463,200 $1,042,200

16 3 Electrical - Controls ea 399 $250 $99,750 $150 1 8 $478,800 $578,550

17 3 TAB ea 386 $150 1 4 $231,600 $231,600

18 3 General Conditions - Ceiling ea 386 $50 $19,300 $150 2 2 $231,600 $250,900

19 3 OA Flow Stations ea 12 $3,000 $36,000 $150 1 8 $14,400 $50,400

Subtotal $4,418,876

1 Means







Total $6,562,276


Sources

Opinion of Probable Construction CostECM-17.03 (c)-1: Complete VAV Conversion on AHU-1B-6B and AHU-1T-7T


ECM-17.03 (C)-2 RETROFIT FANS WITH VFDS / INSTALL BRANCH DUCT

DAMPERS


BASE CASE All six major B-Level AHUs (AHU-1B, 2B, 3B, 4B, 5B, and 6B) are constant volume with hot water preheat coils, chilled water cooling coils, steam humidification, and have fixed fractions of outdoor air. Six of the seven total penthouse AHUs (AHU-1T, 2T, 3T, 4T, 6T, and 7T) are also constant volume and feature the same coil configuration as the basement level AHUs, but feature modulating mixed air dampers with a single-point economizer. AHU-5T is a constant volume make-up air unit that serves patient room induction units.

The supply fan motor nameplate ratings on the AHUs range from 60 hp up to 125 hp and the return fans on applicable AHUs range from 15 to 50 hp. The table below summarizes key parameters for the AHUs included in this measure. AHUs serve zones via 386 constant volume zone reheats equipped with hot water coils.

AHU-# Total


cfm hp hp MBH tons

AHU-1B 49,560 125 30 3,840 433

AHU-2B 59,740 100 20 3,840 195

AHU-3B 58,240 125 25 3,300 240

AHU-4B 58,240 125 30 3,120 210

AHU-5B 41,750 100 25 2,610 165

AHU-6B 52,680 100 30 3,120 210

AHU-1T 35,600 75 25 2,520 175

AHU-2T 43,530 (2) 50 15 2,700 308

AHU-3T 46,400 75 15 2,520 210

AHU-4T 4,320 75 20 2,880 216

AHU-6T 66,500 125 50 3,420 245

AHU-7T 44,940 125 15 3,780 373

ECM # 17.03 (c)-2

Electric

Energy

Savings

Electric Cost

Savings

CHW

Energy

Savings

CHW Cost

Savings

Steam

Savings

Steam

Cost

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


2,429,314 $242,931 1,165,401 $139,848 13,359 $133,589 $516,368 $3,306,679 6.4

Retrofit Fans with VFDs & Install Branch Duct Dampers


PROPOSED CASE This measure proposes retrofitting the supply and return fans on the AHUs included in the table above with VFDs and installing modulating dampers at strategic locations in each AHU’s supply ducts. Each supply fan VFD would be controlled by a new duct static pressure sensor that would be located as far as possible down the supply duct while still being upstream of modulating branch duct dampers. Modulating branch duct dampers are recommended as an alternative to a full VAV conversion by reusing the existing zone reheats. The proposed dampers would be used to implement scheduling in non-critical areas where airflow could be reduced to approximately 70% of existing flow during nighttime periods. The table below summarizes the areas of the building that we propose a scheduled airflow reduction by installing branch duct dampers on each floor. The table also indicates the ratio of areas served by each AHU that we estimate can be turned down at night. For example, we have assumed that critical areas served by AHU-1B, 2T, and 7T would require design airflow at all times and therefore the turndown of this equipment would be less.

AHU-# Areas Served Ratio of Areas for Branch Duct Airflow Reduction

AHU-1B L2 Operating Rooms, L2 Neurology, L1 Emergency Room 30%

AHU-2B Cafeteria 100%

AHU-3B General Supply LB & LA 100%

AHU-4B E.B.S., Bio Med

General Supply LB & LA 100%

AHU-5B General Supply LA, L1, Parts of LB 100%

AHU-6B General Supply LB & L1 100%

AHU-1T Doctors’ Offices

General Supply L3,4,5,6,7,8 100%

AHU-2T 2A-T: L3,6,7 ICU; L4 Nursery

2B-T: L3,5,6,7 ICU; L4 Delivery 30%

AHU-3T Elevator area, hallways, common corridor areas


AHU-4T Nurses Stations


AHU-6T L2 East Side 100%

AHU-7T Laboratory Supply

L2 50%

Each supply fan VFD would be controlled by new duct static pressure sensors to be located in strategic locations upstream of branch duct dampers, in order to ensure that the proper flow balance is maintained at all times. In addition, static pressure sensors would be installed downstream of each branch duct damper to maintain proper flow to each branch zone during


periods when flow is reduced. Branch duct dampers would modulate to maintain a minimum downstream static pressure at all times; in the even the branch duct damper is fully open and static pressure is not met, the AHU supply fan would ramp higher as necessary to maintain the set-point. As part of this measure, we recommend installing outdoor airflow stations on each AHU in order to maintain building pressurization during periods when fans turn down. The existing case outdoor airflow would be maintained at all times by modulating outdoor air dampers and return fan speeds. For B-Level AHUs, the booster fan serving the common outdoor air plenum would be controlled to maintain the necessary outdoor airflow to each unit.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the model systems shown in the table below.


MIN-FLOW-


FAN-CONTROL

MIN-FLOW-RATIO

FAN EIR f(PLR)

FAN-CONTROL













For the ratio of thermal zones served by each AHU indicated in the proposed case table above, the following minimum flow schedule was implemented as part of the parametric run:

Monday - Friday 6:00pm - 6:00am: 70%

Monday - Friday 6:00am - 6:00pm, All Day Saturday - Sunday: 100%


COST ESTIMATE The cost estimate on the following page was developed using budget quotes for VFDs and motors replacement, as well as estimates for installation of branch duct dampers, static pressure sensors, BAS points, programming, TAB, ceiling and duct work, and electrical installation. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable.





(978) 208 - 0609

Total


1 3 As-Builts ea 12 $0 $150 1 24 $43,200 $43,200










12 3 Startup/Freight ea 25 $250 $6,250 $150 $0 $6,250


14 3 BAS Control Points ea 345 $1,500 $517,500 $0 $517,500

15 1 Branch Duct Dampers ea 80 $500 $40,000 $150 2 8 $192,000 $232,000

16 3 Sheetmetal Cut in ea 80 $250 $20,000 $150 2 8 $192,000 $212,000

17 3 TAB ea 92 $150 1 8 $110,400 $110,400

18 3 General Conditions-ceiling ea 80 $50 $4,000 $150 2 8 $192,000 $196,000

19 3 Electrical-controls ea 92 $500 $46,000 $150 1 8 $110,400 $156,400


Subtotal $1,900,079

1 Means







Total $3,306,679

Sources

ECM-17.03 (c)-2: Retrofit Fans with VFDs/ Install Branch Duct Dampers for AHU-1B-6B and AHU-1T,2T,3T,4T,6T,7T




ECM-17.03 (C)-3 RETROFIT FANS WITH VFDS / RESET SPEED BASED ON

OAT


BASE CASE All six major B-Level AHUs (AHU-1B, 2B, 3B, 4B, 5B, and 6B) are constant volume with hot water preheat coils, chilled water cooling coils, steam humidification, and have fixed fractions of outdoor air. Six of the seven total penthouse AHUs (AHU-1T, 2T, 3T, 4T, 6T, and 7T) are also constant volume and feature the same coil configuration as the basement level AHUs, but feature modulating mixed air dampers with a single-point economizer. AHU-5T is a constant volume make-up air unit that serves patient room induction units.

The supply fan motor nameplate ratings on the AHUs range from 60 hp up to 125 hp and the return fans on applicable AHUs range from 15 to 50 hp. The table below summarizes key parameters for the AHUs included in this measure. AHUs serve zones via constant volume 386 zone reheats equipped with hot water coils.

AHU-# Total


cfm hp hp MBH tons

AHU-2B 59,740 100 20 3,840 195

AHU-3B 58,240 125 25 3,300 240

AHU-4B 58,240 125 30 3,120 210

AHU-5B 41,750 100 25 2,610 165

AHU-6B 52,680 100 30 3,120 210

AHU-1T 35,600 75 25 2,520 175

AHU-3T 46,400 75 15 2,520 210

AHU-4T 4,320 75 20 2,880 216

AHU-6T 66,500 125 50 3,420 245

PROPOSED CASE This measure proposes retrofitting the supply and return fans on the AHUs included in the table above with VFDs and resetting the supply fan speed on each AHU based on outdoor air

ECM # 17.03 (c)-3

Electric

Energy

Savings

Electric Cost

Savings

CHW

Energy

Savings

CHW Cost

Savings

Steam

Savings

Steam

Cost

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


3,025,217 $302,522 3,394,859 $407,383 43,237 $432,374 $1,142,278 $929,379 0.8

Retrofit Fans with VFDs & Reset Speed vs OAT


temperature. AHU-1B, AHU-2T, and AHU-7T are not included in this measure since these units serve critical spaces that require design airflow at all times. The table below summarizes the proposed reset schedule.

Outdoor Temperature

Supply Fan VFD Speed

°F %

30°F 60%

70°F 100%

As part of this measure, we recommend installing duct static pressure sensors as far as possible down the supply duct of each AHU that would be used to override the outdoor air reset in the event the duct static dropped below a minimum threshold. Although the system’s terminal devices are constant volume, the static pressure measurement could be used as a tool to ensure that sufficient flow is maintained to the further zones under all conditions. In addition, we recommend installing new temperature sensors in a sample of zones throughout the hospital that would be used to override the supply fan speed outdoor air reset on each AHU. If the zone temperature in any zone reaches more than 2°F (adjustable) above the set-point, the AHU fan speed would reset higher. We also recommend installing outdoor airflow stations on each AHU in order to maintain building pressurization during periods when fans turn down. The existing case outdoor airflow would be maintained at all times by modulating outdoor air dampers and return fan speeds. For B-Level AHUs, the booster fan serving the common outdoor air plenum would be controlled to maintain the necessary outdoor airflow to each unit.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the model systems shown in the table on the following page.



MIN-FLOW-


FAN-CONTROL

MIN-FLOW-RATIO

FAN EIR f(PLR)

FAN-CONTROL

COOL-CONTROL

AHU-2B 1.00 n/a Constant 0.70 VSD FPLR Variable Warmest





AHU-1T 1.00 n/a Constant 0.70 VSD FPLR Variable Warmest




COST ESTIMATE The cost estimate on the following page was developed using budget quotes for VFDs and motors replacement, as well as estimates for installation of new static pressure and zone temperature sensors, BAS points, programming, TAB, and electrical installation. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable.





(978) 208 - 0609

Total


1 3 As-Builts ea 12 $0 $150 1 24 $43,200 $43,200










12 3 Startup/Freight ea 25 $250 $6,250 $150 $0 $6,250


14 3 BAS Control Points ea 24 $1,500 $36,000 $0 $36,000

15 3 Electrical-controls ea 12 $500 $6,000 $150 1 8 $14,400 $20,400

16 3 TAB ea 12 $150 1 16 $28,800 $28,800


Subtotal $533,979

1 Means







Total $929,379

Opinion of Probable Construction CostECM-17.03 (c)-3: Retrofit Fans with VFDs & Reset Speed Based on OAT for AHU-1B-6B and AHU-1T,2T,3T,4T,6T,7T


Sources


ECM-18.00 (C)-1 REPLACE PREHEAT VALVES & ACTUATORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-1 Replace Preheat Valves & Actuators on AHU-1B-6B, 1T-7T


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 33,302 $3,996 400 $3,996 $7,992 $83,700 10.5

BASE CASE Historical trend logs show that upon startup of each major basement (AHU-1B-6B) and penthouse (AHU-1T-7T) AHU preheat coil circulator, the preheat discharge air temperature rises significantly even when the valve was fully closed. This may be due to a leaking valve or insufficient pressure at the pneumatic actuator to hold the valve closed when the coil circulator is on. See Figure 44 on Page 169 for a trend screenshot that illustrates the air temperature rise observed across a typical AHU preheat coil when the pump turns on.

PROPOSED CASE For each of the AHUs listed in the table above, we recommend replacement of the preheat coil valve with a new valve body and replacement of the existing pneumatic actuator with an electric actuator to eliminate the hot water leakage observed when the circulator was enabled. As part of the measure, the valve controls would be converted to fully DDC and the programming updated for an electrically actuated valve.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating energy used during periods when the preheat pumps are active and the heating demand is less than the amount the results from valve leakage. In addition, chilled water savings result from the additional mechanical cooling needed to meet discharge set-points after supply air is preheated more than necessary.

The energy savings associated with this measure were estimated using an 8,760 hour spreadsheet model that calculates the sensible heat gain across each AHU’s preheat coil based on trend data observations. The average temperature rise across each coil was first calculated using trends of mixed air and preheat leaving air temperature during periods when the circulator was on but the preheat valve was closed. For the thirteen AHUs analyzed, this average differential ranged from 0.25°F to 7.1°F. Energy savings were then calculated and extrapolated using TMY3 weather data for Worcester, MA. For each AHU, if the hourly outdoor air temperature was greater than the point at which heating was required but less than or


equal to the pump enable temperature (50°F for all AHUs), wasted heating energy was calculated using the following equation:

𝑄 [𝐵𝑡𝑢

ℎ𝑟] = 1.08 ∗ 𝑆𝑢𝑝𝑝𝑙𝑦 𝐴𝑖𝑟𝑓𝑙𝑜𝑤 [𝑐𝑓𝑚] ∗ 𝐴𝑣𝑒𝑟𝑎𝑔𝑒 𝐶𝑜𝑖𝑙 𝛥𝑇 [°𝐹]

Where ‘Supply Airflow’ is equal to each AHU’s total supply airflow documented in the latest available testing, adjusting, and balancing (TAB) report.

Heating energy savings (Btu) were summed across all AHUs for the entire year and divided by a steam heating value of 1,000 Btu/lb to calculate the measure’s annual steam savings (Lbs).


Figure 44: The trends screenshot for AHU-2B below shows the large difference between preheat leaving air temperature (PINK) and mixed air temperature (LIGHT BLUE) when the preheat circulator status (ORANGE) is on but the preheat control valve (RED) is closed. The typical speed of the circulator VFD (DARK BLUE) ranges between 40-50% during these periods.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 6 $900 $900


3 3 4 in. Control Valve ea 13 $450 $5,850 $150 2 4 $15,600 $21,450

4 3 Valve Actuator ea 13 $350 $4,550 $150 1 2 $3,900 $8,450

5 3 Insulation Repair ea 13 $150 $1,950 $150 1 2 $3,900 $5,850

6 3 DDC Control Point ea 13 $250 $3,250 $150 1 4 $7,800 $11,050

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $51,600

1 Means







Total $83,700

Opinion of Probable Construction CostECM-18.00 (c)-1: Replace Preheat Valves & Actuators on AHUs 1B-6B and AHU-1T-7T


Sources


ECM-18.00 (C)-2 LOCK-OUT HUMIDIFICATION & CALIBRATE HUMIDITY

SENSORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-2 Lock-out Humidification & Calibrate Return Air %RH Sensors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 0 $0 2,408 $24,081 $24,081 $38,200 1.6

BASE CASE All major mixed air AHUs at the hospital are equipped with steam humidification and fixed return air relative humidity minimum set-points. However, the humidification valves on many of the AHUs were found to be open throughout the summer as a result of low return air relative humidity measurements. Figure 45 on Page 173 shows a historical trend of the return air relative humidity measurements and steam humidification valve positions for a sample of the major Hospital AHUs.

At the typical AHU summer discharge air temperature of 55°F, it is unlikely that return air relative humidity would be below the minimum set-point of 30%, especially when considering the latent heat added at the zone level from infiltration and occupants. As a result, the relative humidity sensors may be out of calibration. The list below includes the AHUs found to have a potential calibration issue.

B-LEVEL T-LEVEL

AHU-1B AHU-1T

AHU-2B AHU-2T

AHU-4B AHU-3T

AHU-5B AHU-4T

AHU-6B AHU-5T

AHU-6T

AHU-7T

PROPOSED CASE We recommend implementing a summer humidification lockout on the AHUs listed in the table above when outdoor air temperatures are greater than 70°F. We also propose calibrating each of the AHU return air relative humidity sensors to ensure that humidification equipment is controlling to an accurate target during periods when the system is enabled.


ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in steam consumption during periods when the AHU return air relative humidity sensors were reading low and humidification was not necessary.

The energy savings associated with this measure were estimated using a bin spreadsheet model that calculated the average steam humidifier load on each AHU included in this measure during periods when the outdoor air temperature was greater than 70°F. Humidifier load was estimated based on historical trend data of steam valve position available between 5/3/2014 - 7/31/2014 and the nameplate capacity of each AHU’s humidifier. Energy savings were extrapolated to the entire year using TMY3 weather data for Worcester, MA by multiplying the average humidifier load by the annual number of hours that the outdoor air temperature is greater than 70°F (906). Steam savings assumed a heating value of 1,000 Btu/lb.


Figure 45: Trend screenshot of AHU-1B showing the steam humidification valve opening 100% during periods when the return air relative humidity is below the minimum set-point of 35%.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 8 $1,200 $1,200



4 3 Sensor Calibration ea 8 $0 $150 1 4 $4,800 $4,800

5 3 Sensor Replacement ea 4 $750 $3,000 $150 1 1 $600 $3,600

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $20,400

1 Means







Total $38,200

Sources

Opinion of Probable Construction CostECM-18.00 (c)-2: Lock-out Humidification & Calibrate Humidity Sensors on AHU-1B-6B and AHU-1T-7T



ECM-18.00 (C)-3 REPLACE LEAKING PREHEAT VALVE ON AHU-13T

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-3 Replace Leaking Preheat Valve on AHU-13T


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 12,333 $1,480 148 $1,480 $2,960 $5,000 1.7

BASE CASE AHU-13T is a make-up air unit that serves bone marrow transfer unit. During the summer, trend data suggests the preheat valve on AHU-13T is leaking by, with a 20°F average temperature rise between the outdoor air temperature and the unit discharge temperature observed when the preheat valve commanded fully closed. This results in wasted heating and cooling energy necessary to maintain the discharge air temperature set-point. Figure 48 on Page 190 shows an example trend screenshot that illustrates this issue. The table below summarizes key specifications for AHU-13T and its discharge air set-point reset schedule.

HVAC Type

Supply

Fan HP

Supply

Fan Qty

Measured

Supply Air Flow

Constant Volume 3 HP 1 2,909 CFM

Zone Temp

Error

Unit DAT

set-point

-1oF 57 oF

1oF 95 oF

Unconditioned outdoor air is initially preheated by a separate coil upstream of AHU-13T during the winter. This coil controls to the leaving air set-point reset schedule below, and was integrated into the energy model.

OAT PHT set-

point

5oF 62 oF

50 oF 55 oF


Figure 46: The trend screenshot below shows the preheat valve (BLUE) and chilled water valve (RED) positions on AHU-13T, as well as the temperature of the air entering the AHU (PINK) and the discharge air temperature (ORANGE). The areas highlighted in gray show periods when only the chilled water valve was 60-70% open, but the discharge air temperature was equal to or greater than the entering (outdoor) air temperature. This is likely due to a leaking preheat valve.


PROPOSED CASE We recommend replacing AHU-13T’s preheat valve to eliminate leak-by.

ENERGY SAVINGS METHODOLOGY This savings associated with this measure were calculated using a customized, hourly spreadsheet model. Hourly TMY3 data was used for Worcester, MA. The magnitude of the leakby was calculated for each hour of the year and the resulting excess heating load was calculated using the formula below:

𝑄𝑆𝑖𝑚 𝐻𝑒𝑎𝑡/𝐶𝑜𝑜𝑙 = 1.08 × 𝐶𝐹𝑀𝑆𝑢𝑝𝑝𝑙𝑦 × ∆𝑇𝐶𝑜𝑜𝑙𝑖𝑛𝑔

Where,

Qsim heat/cool = simultaneous heating and cooling load from leakby, in Btu/hr. This load occurs

on both the heating and cooling coils.

CFMSupply = Total supply CFM across preheat and cooling coils.

∆Tpreheat = 𝑇𝐷𝐴 > 𝑇𝑀𝐴 + 𝑇𝑆𝐹 = Magnitude of the temperature drop across the cooling coil

𝑇𝐷𝐴= discharge air temperature

𝑇𝑀𝐴= mixed air temperature

𝑇𝑆𝐹= calculated temperature rise resulting from supply fan sensible heat dissipation

The temperature rise across the fan and motor is calculated with the following equation:

∆𝑇𝑆𝐹 = 2545 ∗ 𝑃 ∗ [(1 − 𝐸𝐹) + (

1𝐸𝑀

− 1)]

1.08𝑄

Where, ΔTSF = Temperature Rise across Motor and Fan 2545 = Btu/hp P = Shaft Power (bhp) EM = Motor Efficiency 1.08 Btu/hr-CFM-°F Q = Air Flow Rate (CFM)

Modeling Assumptions:

Simultaneous load on the cooling coil is equal in magnitude to the leakby load on the preheat coil.

In both the base & proposed case, the unit continuously operates at 100% outdoor air.


COST ESTIMATE The estimated cost for this measure includes an allocation for the replacement of the chilled water valve and commissioning following installation. An estimated opinion of probable cost for this measure is presented in the chart below.




(978) 208 - 0609

Total



2 1 2 in. Control Valve ea 1 $350 $350 $150 1 8 $1,200 $1,550

3 1 Insulation Repair ea 1 $150 $150 $150 1 2 $300 $450

4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $2,600

1 Means







Total $5,000

Opinion of Probable Construction CostECM-18.00 (c)-3: Replace Leaking Preheat Valve on AHU-13T


Sources


ECM-18.00 (C)-4 DUCT STATIC PRESSURE RESET ON AHU-1R, 15T/16T

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-4 Duct Static Pressure Reset on AHU-1R, 15T/16T


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


9,665 $967 3,250 $390 14 $135 $1,492 $19,700 13.2

BASE CASE AHU-1R is a multi-zone VAV AHU that serves the Hospital’s new 2nd floor Catheterization Lab. The unit has a 32,000 cfm design supply airflow, a 60 hp supply fan motor, 30 hp return fan motor, and controls to a fixed duct static pressure set-point of 1.5” WC.

AHU-15T and AHU-16T are both multi-zone VAV AHUs that serve the Hospital’s new 8th floor Bone Marrow Transplant Unit (BMTU). One AHU in the pair runs at all times, with the other serving as a backup in the event of a failure. Each unit has a 7,730 cfm design supply airflow, a 15 hp supply fan motor, 7.5 hp return fan motor, and controls to a fixed duct static pressure set-point of 1.7” WC.

PROPOSED CASE We propose resetting the duct static pressure set-point on AHU-1R and AHU-15T/16T using a new cascading control algorithm. Every 15 minutes the BAS will perform a damper position “high select” on all VAV boxes served by each AHU. If the average of the top two “high select” boxes is between 85% and 90% open the system shall hold its current duct static pressure set-point. If the average is below 80% open the BAS logic shall cascade its static pressure set-point down to a low of 0.8” WC. If the “high select” average of the top five boxes is greater than 90% then the system duct static pressure set-point shall cascade up to maximum (1.5” WC for AHU-1R, 1.7” WC for AHU-15T/16T). The cascading reset loop shall be tuned to avoid unnecessary hunting.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on hAHU1R and hAHU15T/16T and changed the supply fan “EIR f(PLR)” performance curve that calculates fan input power as a function of airflow part load ratio. The curve used in the base case is the standard curve available from the eQuest library. A custom curve was developed for the proposed case to model a demand-based duct static pressure reset.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $10,800

1 Means







Total $19,700

Opinion of Probable Construction CostECM-18.00 (c)-4: Duct Static Pressure Reset on AHU-1R, 15T/16T


Sources


ECM-18.00 (C)-5 ADJUST AHU-1L TEMPERATURE CONTROL

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-5 Adjust AHU-1L Temperature Control


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


27,088 $2,709 10,771 $1,293 36 $360 $4,361 $4,100 0.9

BASE CASE AHU-1L is a single zone variable volume AHU that serves the Hospital’s Remillard Lobby. The unit has a 10,000 cfm design supply airflow, a 15 hp supply fan motor, 3 hp return fan motor, and a single point economizer.

Historical trend data for AHU-1L shows that the unit’s discharge air temperature resets to maintain the zone temperature set-point. However, the unit consistently cycles between full heating and cooling, hunting to maintain the set-point. Figure 47 on Page 183 shows how the preheat and chilled water valves cycle between 0% and 100% open, and the supply fan speed cycles between its minimum speed (62%) in heating and near 100% speed in cooling. This control sequence may be causing excess fan, heating, and cooling energy to maintain the zone at set-point.

PROPOSED CASE We recommend implementing a heating/cooling set-point dead-band of 2°F and reconfiguring the AHU’s temperature control loop to be less sensitive in order to reduce excessive cycling. In the proposed case, the occupied zone heating set-point would be 71°F and the occupied cooling set-point would be 73°F. The dead-band will allow the zone temperature to drift from one set-point to the other before switching between heating and cooling modes, and may reduce energy consumption during mild outdoor air conditions.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in fan, heating, and mechanical cooling energy used by AHU-1L as a result of unnecessary cycling between heating and cooling modes.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on hAHU1L and changed the following parameters:

Base Case


THROTTLING-RANGE: 0.1°F


COOL-TEMP-SCH: AHU-1L Cool Ann

HEAT-TEMP-SCH: AHU-1L Heat Ann Proposed Case


THROTTLING-RANGE: 2°F

COOL-TEMP-SCH: 247 Cool Ann

HEAT-TEMP-SCH: 247 Heat Ann


Figure 47: The trend screenshot below of AHU-1L shows that supply chilled water valve (DARK BLUE) and hot water valve (ORANGE) on the unit constantly cycles between 0% and 100% to maintain the zone temperature (LIGHT BLUE) at the 72°F set-point. The supply fan VFD speed (RED) also changes constantly, ramping up in cooling and ramping down in heating.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 2 $300 $300



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $2,100

1 Means







Total $4,100

Opinion of Probable Construction CostECM-18.00 (c)-5: Adjust AHU-1L Temperature Control


Sources


ECM-18.00 (C)-6 OPTIMIZE HEAT EXCHANGER RESET SCHEDULE

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-6 Optimize Heat Exchanger Reset Schedule


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-1,566 -$157 0 $0 526 $5,256 $5,099 $12,000 2.4

BASE CASE Historical trend data shows that hot water supply set-point on HX-1, 2, 3, 4, and 7 resets based on outdoor air temperature according to the limits shown in the table below.

Outdoor Temperature

HWST Set-point

°F °F

0°F 180°F

60°F 160°F

PROPOSED CASE We recommend revising the existing hot water reset on HX-1, 2, 3, 4, and 7 to increase the system’s efficiency during periods of low thermal load. During the summer months, a hot water supply temperature of 160°F may not be necessary to satisfy induction unit and terminal reheat loads. The table below summarizes the proposed reset parameters.

Outdoor Temperature

HWST Set-point

°F °F

0°F 180°F

60°F 140°F

ENERGY SAVINGS METHODOLOGY Energy savings are derived from an increase in the hot water distribution system’s efficiency by reducing losses through piping, fittings, pumps, and the heat exchangers at lower hot water supply temperatures.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the “HW Loop” system which models HX-1, 2, 3, 4, and 7. The following parameters were changed as part of the parametric run.


Base Case

HEAT-SETPT-CTRL: OA-RESET

HEAT-RESET-SCH: Schedule RESET-TEMP


o Outdoor Drybulb Low Temperature: 0°F



Proposed Case












(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 4 $600 $600



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $6,600

1 Means







Total $12,000

Opinion of Probable Construction CostECM-18.00 (c)-6: Optimize Heat Exchanger Reset Schedule on HX-1-4 and HX-7


Sources


ECM-18.00 (C)-7 REPLACE LEAKING CHILLED WATER VALVE ON AHU-11T

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-7 Replace Leaking CHW Valve on AHU-11T


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 18,390 $2,207 223 $2,228 $4,435 $4,650 1.0

BASE CASE AHU-11T is a dedicated outdoor air system that serves bone marrow transfer unit. During the heating season, the OA is preheated in a separate unit, prior to entering AHU-11T. The cooling valve on AHU-11T is leaking by, with a 15°F average temperature drop between the preheat air temperature and the unit discharge temperature observed when both the heating and cooling valves are commanded fully closed. This results in wasted cooling energy as well as an extra simultaneous load on the heating coil whenever 15°F of cooling is not required. The tables below shows AHU-11T specifications and DAT reset schedule.

HVAC Type

Supply

Fan HP

Supply

Fan Qty

Measured

Supply Air Flow

Constant Volume 3 HP 1 1,830 CFM

OAT Unit DAT

set-point

0oF 75 oF

65 oF 55 oF

The preheat temperature set-point follows the reset schedule below, and was integrated into the energy model.

OAT PHT set-

point

5oF 62 oF

50 oF 55 oF


The graph below shows the difference between outdoor air temperature (OAC) and supply air temperature (SAT), as well as supply air temperature set-point (SAT), heating coil output (HCO), and cooling coil output (CCO). The two gray highlighted areas represent occurrences in June, during which the heating valve is open, and the cooling valve appears closed. In actuality, the cooling valve is leaking by, causing a temperature drop that the heating coil needs to compensate for. During such mild weather, heating should not be needed, and represents wasted energy. During colder months, the cooling energy is not required at all, and represents even more wasted energy.


Figure 48: The trend screenshot below shows the preheat valve (BLUE) and chilled water valve (RED) positions on AHU-11T, as well as the temperature of the air entering the AHU (PINK) and the discharge air temperature (ORANGE). The areas highlighted in gray show periods when only the preheat valve was open, but the discharge air temperature was equal to or lower than the entering (outdoor) air temperature. This is likely due to a leaking chilled water valve.


PROPOSED CASE Repair or replace chilled water valve actuator and replace valve if needed to eliminate leakby. No other changes are made to the unit.

ENERGY SAVINGS METHODOLOGY This savings associated with this measure were calculated using a customized, hourly spreadsheet model. Hourly TMY3 data was used for Worcester, MA. The magnitude of the leakby was calculated for each hour of the year and the resulting excess cooling load was calculated using the formula below:


Where,









∆𝑇𝑆𝐹 = 2545 ∗ 𝑃 ∗ [(1 − 𝐸𝐹) + (

1𝐸𝑀

− 1)]

1.08𝑄






COST ESTIMATE The estimated cost for this measure includes an allocation for the replacement of the chilled water valve and commissioning following installation. An estimated opinion of probable cost for this measure is presented in the chart below.




(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 2 $300 $300



4 ea $0 $150 $0 $0

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $2,450

1 Means







Total $4,650

Sources

Opinion of Probable Construction CostECM-18.00 (c)-7: Replace Leaking Chilled Water Valve on AHU-11T



ECM-18.00 (C)-8 FIX MIXED AIR DAMPER ISSUES TO IMPROVE

ECONOMIZER

MEASURE ECONOMICS SUMMARY ECM # 18.00 (c)-8 Fix Mixed Air Dampers to Improve Economizer


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-213 -$21 72,310 $8,677 -533 -$5,329 $3,327 $22,500 6.8

BASE CASE AHU-2T, 3T, 4T, and 7T are multi-zone constant volume AHUs that serve Level 3 through Level 8 of the Hospital. Each AHU features an economizer sequence with a 70°F outdoor air lock-out. However, trends of outdoor air, return air, mixed air temperature suggest that when the outdoor air damper is commanded fully open, the return air damper is not closing completely or sealing well. Figure 49 on Page 195 shows that when AHU-2T’s outdoor air damper position is 100%, the mixed air temperature is between the outdoor air and return air temperatures. The table below summarizes the estimated actual maximum outdoor air ratio achieved while economizer is enabled for each AHU included in this measure.

AHU-# Maximum % OA

AHU-2T 65%

AHU-3T 88%

AHU-4T 92%

AHU-7T 95%

PROPOSED CASE We recommend inspecting the mixed air dampers on the four AHUs listed in the table above and making improvements as needed to ensure that the outdoor air dampers are fully opening and return air dampers are closing tightly. This may include adjusting pneumatic damper actuator spring tension, replacing damper seals, or adjusting damper linkages.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in mechanical cooling energy used by increasing the maximum outdoor air ratio to 100% during periods when economizer is enabled.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on hAHU-2T, hAHU3T, hAHU4T, and hAHU7T, and changed the following parameters:


Parameter hAHU2T hAHU3T hAHU4T hAHU7T

BASE MAX-OA-FRACTION 0.65 0.88 0.92 0.95

OA-CONTROL OA Temperature

PROPOSED MAX-OA-FRACTION 1.00 1.00 1.00 1.00

OA-CONTROL OA Temperature


Figure 49: The trend screenshot below shows the mixed air (BLUE), return air (ORANGE), and outdoor air (RED) temperature measurements for AHU-2T, as well as the mixed air damper position (PINK). The shaded areas show that when the outdoor air damper is fully open, the mixed air temperature does not equal the outdoor air temperature as would be expected; the calculated quantity of outdoor air is approximately 65%.






(978) 208 - 0609

Total


1 3 As-Builts ea 1 $0 $150 1 2 $300 $300


3 3 Damper Investigation and Testing ea 4 $0 $150 2 2 $2,400 $2,400

4 3 Damper Improvements ea 4 $500 $2,000 $150 2 4 $4,800 $6,800

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $11,900

1 Means







Total $22,500

Opinion of Probable Construction CostECM-18.00 (c)-8: Fixed Mixed Air Damper Issues to Improve Economizer on AHU-2T-4T and AHU-7T


Sources


ECM-21.02 (C) HOSPITAL SOLAR HOT WATER

MEASURE ECONOMICS SUMMARY ECM # 21.02 (c) Hospital Solar Hot Water


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 0 $0 644 $6,437 $6,437 $539,439 83.8

MEASURE DESCRIPTION Solar water heating is the conversion of sunlight into renewable energy for water heating using a solar thermal collector. The solar hot water system proposed by BEAM includes a glazed flat plate collector system consisting of 96 7’x4’ panels with a total surface area of 2,697 ft2. The target loads for the heating system in the Hospital building are shows, bathroom sinks, and the kitchen/cafeteria, which are estimated at 3,500 gallons/day. The system would include a 2,700 gallon buffer tank to be installed in the 9th floor mechanical room, adjacent to the existing 1,980 gallon domestic hot water tanks. For more details, refer to the BEAM’s report in the Appendix, which includes additional details on the proposed solar hot water systems for the Hospital and School buildings.


OTHER OPPORTUNITIES REVIEWED

ECONOMIZER IMPROVEMENTS ON AHU-1B-6B


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-664 -$66 883,491 $106,019 -5,100 -$51,002 $54,950 - -

All six major B-Level AHUs (AHU-1B, 2B, 3B, 4B, 5B, and 6B) are constant volume with hot water preheat coils, chilled water cooling coils, steam humidification, and have fixed fractions of outdoor air. According to the most recent balancing reports, the fixed fraction ranges between 32% and 50%, with the average being 38%. Outdoor air is supplied to these AHUs via a large shaft that connects to an intake plenum located at the penthouse level. The shaft is pressurized using an axial fan equipped with a 60 hp nameplate motor and a VFD that operates at a fixed speed of 40 Hz (67%). At this speed, the outdoor airflow through the fan is approximately 147,000 cfm, according to a memo attached to the fan’s VFD enclosure.

The original HVAC airflow riser diagram (Plan No. H-31) suggests that each basement AHU features relief dampers and ducts that could exhaust air to the Level A Areaway. However, upon further investigation, it was determined that all basement AHUs do not have any form of return relief. All exhaust air leaves the zones served by the basement AHUs via dedicated exhaust fans, stack effect, and/or exfiltration.

We propose investigating the feasibility of installing return air relief or increasing zone-level exhaust in tandem with a new sequence operation for the outdoor air booster fan VFD in order to take greater advantage of outdoor air during mild weather. The sequence would consist of increasing the speed of the booster fan VFD to 100% and reducing the amount of recirculated air to raise the fraction of outdoor air when conditions are appropriate.

This opportunity would require further investigation to determine if it would be feasible considering the location, configuration, and size of the basement AHUs.

Potential energy savings are derived from the reduction in mechanical cooling energy that is used to condition mixed air during periods when an economizer sequence could be active.

The potential energy savings were estimated using a parametric run of the baseline eQuest model. The run was performed on the following model systems: hAHU1B, hAHU2B, hAHU3B, hAHU4B, 7B, hAHU5B, and hAHU6B. The parametric run changed the following parameters:


Parameter hAHU1B hAHU2B hAHU3B hAHU4B,7B hAHU5B hAHU6B

BASE MIN-OUTSIDE-AIR 0.33 0.39 0.35 0.71 0.39 0.31

OA-CONTROL Fixed Fraction

PROPOSED

MIN-OUTSIDE-AIR 0.33 0.39 0.35 0.71 0.39 0.31

MAX-OA-FRACTION 0.55 0.57 0.55 0.92 0.78 0.54

OA-CONTROL OA Enthalpy

ENTHALPY-LIMIT 24 Btu/lb

200 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Lakeside

LAKESIDE EXECUTIVE SUMMARY TABLE


ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


01.01 (d) Lighting Retrofit 61,418 0 0 $6,142 $133,865 21.8

04.09 (d) Modify Mixed Air Temperature Control on AHU 1-10 0 67,135 3,106 $39,119 $27,900 0.7

04.13 (d) Install Occupancy Sensors in Operating Rooms 97,720 20,518 721 $19,448 $115,600 5.9

18.00 (d)-1 Discharge Air Temperature Reset on AHU 1-10 -41,322 810,228 12,559 $218,688 $33,700 0.2

18.00 (d)-2 Static Pressure Reset on AHU 1-8 198,073 49,857 -5 $25,736 $31,700 1.2

18.00 (d)-3 Reconfigure Preheat Circulator Control on AHUs 1-10 8,175 0 0 $817 $27,900 34.1

18.00 (d)-4 Optimize HWST Reset 4 0 547 $5,475 $8,200 1.5

18.00 (d)-5 Replace AHU-4 Return Temperature Sensor 0 1,074 6 $184 $3,900 21.2

18.00 (d)-6 Replace Leaking CHW Valve on AHU-2 0 131,378 1,651 $32,273 $8,150 0.3

324,067 1,080,190 18,585 $347,882 $390,915 1.1TOTALS



The Lakeside building on the UMMC campus is approximately 270,000 ft2 and stands 3 stories tall. The Lakeside also has two sub-grade levels. It was constructed in 2004, and features a 60,000 ft2 emergency department accommodating more than 100,000 patient visits annually, along with 10 operating suites, an ICU, and patient & family care centers. Most areas in the facility are occupied 24 hours per day.

Steam and chilled water (CHW) are provided by the central plant. There are no tertiary CHW pumps in the building. All air handlers using chilled water operate off the pressure of the central loop. The Lakeside building receives steam from the central plant at 50 psig for HVAC loads and 125 psig for sterilization.

There is (1) steam to hot water (HW) heat exchanger (HX) that serve AHUs, fan coil units, and reheat coils. The HX has a set of three constant volume pumps, two of which operate at any given time to circulate the HW throughout the building.

There are (10) air handling units (AHUs) serving the building, all of which are located in mechanical spaces on the third floor. The units are referred to as AHU-1 through AHU-10. (8) of the air handlers serve the majority of spaces throughout the building, with AHU-9&10 serving second floor operating rooms. AHU-9 and AHU-10 operate lead/lag such that only one unit operates at a time; in the event of a failure, the lag AHU automatically starts. These units rotate lead and lag roles on a regular basis to balance run hours on the equipment.

All AHUs in the building are variable volume with supply and return fan VFDs and all feature economizer capabilities with a preheat coil, steam humidifier, and cooling coil. These units are all equipped with dedicated preheat coil circulators, which are used for freeze protection and to maintain the necessary hot water flow. HW coils have three-way valves while CHW coils have two-way valves. All units have a design capacity of 40,000 cfm, and a minimum outside air percentage of 33%. These primarily serve variable volume boxes, some of which are equipped with HW reheat coils. There are also approximately (4) Fan coil units (FCUs) that primarily serve mechanical and storage spaces in the basement.

There are also (8) pressurization fans serving elevators & stairwells and approximately (25) building exhaust fans serving isolation rooms, mechanical rooms, electrical rooms, and general exhaust. Exhaust fans range in size from 3,000 cfm to 23,000 cfm. Pressurization fans run only in the event of a fire and approximately half of exhaust fans run 24/7.

Lakeside HVAC is primarily controlled by the Siemens building automation system (BAS). Air handlers typically control to a constant discharge air temperature set-point of 55oF, however AHU-3 was seen to control to 60oF. The HX has an reset schedule based on outdoor air temperature for the hot water supply temperature set-point.




ENERGY USE GRAPHS

ELECTRICITY The top graph below shows electricity use for the Lakeside for fiscal years (FYs) 11 – 14. It can be seen that electricity use is very consistent throughout the year, with slight variations between the years likely due to weather effects. The bottom graph shows the electric use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 50: Lakeside monthly electricity use (kWh) for Fiscal Years 2011 - 2014.

Figure 51: Lakeside baseline electricity use (kWh) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000


Ele

ctri

c U

se (

kWh

)

Lakeside Electric Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000


Ele

ctri

c U

se (

kWh

)

Lakeside Baseline Electric Use

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-13)


STEAM The top chart below shows the monthly steam consumption for FYs 11 – 14. It can be seen that there is a significant difference between steam use in some months. This may be due to differences in meter read dates, but may also be due to known issues with the accuracy of the Lakeside steam meter. Also note the significant increase in summer steam usage seen in FY14. The bottom graph shows the steam use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 52: Lakeside monthly 50 lb steam energy use (Lbs) for Fiscal Years 2011 - 2014.

Figure 53: Lakeside baseline 50 lb steam energy use (Lbs) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

0

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000

6,000,000


Ste

am U

se (

lbs)

Lakeside 50# Steam Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000

6,000,000


Ste

am U

se (

lbs)

Lakeside Steam Use FY 11 - FY 13

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-13)


CHILLED WATER The top chart below shows the Lakeside CHW use from FYs 11 – 14. It can be seen that CHW use is very consistent from year to year, with slight variations between the years likely due to weather effects. The bottom graph shows the CHW use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 54: Lakeside monthly chilled water energy use (ton-days) for Fiscal Years 2011 - 2014.

Figure 55: Lakeside baseline chilled water energy use (ton-days) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

0

5,000

10,000

15,000

20,000

25,000


Ch

ille

d W

ate

r U

se (

ton

-day

s)

Lakeside CHW Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

5,000

10,000

15,000

20,000

25,000


Ch

ille

d W

ate

r U

se (

ton

-day

s)

Lakeside Baseline CHW Use

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-13)


BENCHMARKING

BENCHMARKING SUMMARY TABLE The table on the following page summarizes the annual energy consumption and performance metrics for the facility. This was done to provide a clear representation of the actual site and estimated equivalent source energy consumption for benchmarking and also for evaluation with energy savings opportunities. Energy use data for Fiscal year 2011 – 2013 is shown in the table, along with an average of data from the three fiscal years.


Energy Use


Performance Ratings










FY11 7,864,925 2,425,344 23,570 29.1 3.33 99.4 107.79 5.7 12.8 87 0 109 295 241

FY12 7,812,691 2,649,024 20,110 28.9 3.30 98.8 117.73 6.3 14.0 74 0 93 291 227

FY13 7,732,755 2,389,392 21,210 28.6 3.27 97.7 106.20 5.7 12.6 79 0 98 282 228

3 Year Avg. 7,803,457 2,487,920 21,630 28.9 3.30 98.6 110.57 5.9 13.2 80 0 100 289 232

UMass Medical Center Lakeside Building Energy Use Data


Floor


Steam Total

Source Source

CHW

270,000



Energy and cost savings were estimated using an existing eQuest model of the facility originally developed by Andelman & Lelek and modified to reflect current equipment characteristics, schedules, and internal loads. The model used the TMY3 weather file for Worcester, MA and was calibrated against monthly utility use over a three year period from July 2010 – July 2013. The model was also calibrated for chilled water and steam use using monthly data obtained from the UMass central plant staff. The charts below compare the actual monthly utility use averaged over FY2011-2013 and the calibrated eQuest model predicted utility use. Operation of the building was inferred from a review of trend data, generally extending from May 2014 to September 2014.

Monthly electricity and chilled water use were able to be reasonably calibrated to utility data. Peak winter steam usage was also able to be calibrated; however there was a major discrepancy with the steam use during warmer months. Based on discussions with facilities staff, the Lakeside steam meter has known calibration and turndown issues, and is planned for replacement.

Figure 56: Lakeside building eQuest model electricity use calibration chart. The baseline monthly electricity use utility data is shown in blue and the eQuest model predicted monthly electricity consumption is shown in red.

0

100,000

200,000

300,000

400,000

500,000

600,000

700,000

800,000

Ele

ctri

city

Usa

ge (

kWh

)

Monthly Electricity Usage - Lakeside

UtilityData

eQUESTOutput


Figure 57: Lakeside building eQuest model chilled water calibration chart. The baseline monthly chilled water utility data is shown in blue and the eQuest model predicted monthly chilled water energy consumption is shown in red.

0

100,000

200,000

300,000

400,000

500,000

600,000

Ch

illed

Wat

er U

sage

(to

n-h

r)

Monthly Chilled Water Usage - Lakeside

UtilityData

eQUESTOutput


Figure 58: Lakeside building eQuest model steam calibration chart. The baseline monthly steam utility data is shown in blue and the eQuest model predicted monthly steam consumption is shown in red.

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

Stea

m U

sage

(M

lb)

Monthly Steam Usage - Lakeside

UtilityData

eQUESTOutput


Table 8 on Page 214 summarizes the annual end-use energy distribution for electricity, steam, and CHW at the facility as calculated by the baseline eQuest model. The pie chart on the following page illustrates the baseline eQuest model’s electricity end use using the figures shown in the table.


The following parameters were used to model the estimated miscellaneous loads in the Hospital building, based on information gathered during walkthroughs and historical whole-building electricity use:

1. Lobby, Café, and Corridor Plug Loads: 0.10 W/ft2


3. Patient Room, Clinic, and ER Patient Area Plug Loads: 1.0 W/ft2

4. Laboratory, MRI, ICU, and Surgery Plug Loads: 3.0 W/ft2

5. Kitchen Plug Loads: 10.0 W/ft2


1. Patient Room Lighting Power Density: 0.70 W/ft2

2. Corridor Lighting Power Density: 1.0 W/ft2


4. Kitchen Lighting Power Density: 1.2 W/ft2

5. Laboratory and Exam Room Lighting Power Density: 1.4 - 1.5 W/ft2

6. Surgery and ICU Lighting Power Density 2.2 W/ft2


Table 8: Lakeside Building eQuest model’s annual energy end-use for each meter (electricity, steam, and chilled water).

Figure 59: Pie chart showing Lakeside Building eQuest model’s annual electricity end use breakdown.

kWh MLb ton-hrs


Task lighting 0 0 0

Misc. Equip. 2,755,013 174 0






Refrigeration 0 0 0

Heat Pump 0 0 0

Hot Water 0 0 0

Exterior 0 0 0

Total 7,792,048 37,616 1,895,914


End Use


ECM-01.01 (D) LIGHTING RETROFIT

MEASURE ECONOMICS SUMMARY ECM # 01.01 (d) Lighting Retrofit


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


61,418 $6,142 0 $0 0 $0 $6,142 $133,865 21.8

BASE CASE The lighting consists primarily of 1’ by 4’ fixtures with 32 Watt T8 lamps, and 2’ by 4’ fixtures, also with two or three lamp 32 Watt T8 lamps. There is also a significant quantity of recessed can fixtures containing 13 Watt compact florescent lamps (CFLs). The lens type on the fixtures is primarily either prismatic or volumetric. The cans do not have a lens.

PROPOSED CASE This measure proposes to upgrade existing lamps and ballasts to newer high efficiency units where applicable. Refer to the Opinion of Probable Cost Table on the following page for a breakdown of proposed equipment types and quantities. We recommend replacing 4’ 32 Watt T8 lamps with high efficiency 28 Watt lamps and NEMA Premium (NP) electronic ballasts. We also recommend replacing CFLs and incandescent floods with LED lamps. The recommendations do not include fixture upgrades or replacement in an effort to present a more effective retrofit approach. Lighting controls such as occupancy sensors are not recommended due to the nature of the spaces and the 24/7 building operation.

ENERGY SAVINGS METHODOLOGY

Energy savings are derived from the reduction in electricity use by installing high efficiency fluorescent lamps and more efficient ballasts. The energy savings calculations make estimates for annual run hours of each fixture based on information obtained from facilities and maintenance staff. The calculations assume that run hours remain the same in the proposed case.

ASSUMPTIONS The audit was performed, room-by-room, on all of the floors in the building. An audit was done on the staff areas, (referred to as ‘Pods’), and extrapolated to like areas in the building. The operating room areas on floor two were inaccessible, and are not included in the audit and resulting kWh and cost numbers. Occupancy sensing and other lighting controls are excluded from this measure due to the nature of the spaces served and 24/7 building operation.




100 Burtt Rd. Ste. 212 Address: Lakeside Building Estimated By: KK


(978) 208 - 0609


1 3-Audit



2 3-Audit


with 3 Lamp 28 Watt T8 with NP Ballast ea 10 $60 $600 $0 0 0 $0 $600

3 3-Audit



4 3-Audit


with 1 Lamp 25 Watt T8 with LP Ballast ea 433 $45 $19,485 $0 0 0 $0 $19,485

5 3-Audit



6 3-Audit



7 3-Audit


with 4 Lamp 25 Watt T8 with LP Ballast ea 42 $65 $2,730 $0 0 0 $0 $2,730

Opinion of Probable Construction CostECM-01.01 (d): Retrofit Lighting Fixtures






(978) 208 - 0609


8 3-Audit


with 3 Lamp 25 Watt T8 with LP Ballast ea 12 $60 $720 $0 0 0 $0 $720

9 3-Audit



10 3-Audit

Retrofit - 2 Foot 2 U Lamp 17 Watt T8 with NP

Ballast with 2 Foot 2 Lamp 17 Watt T8 with LP

Ballast ea 12 $55 $660 $0 0 0 $0 $660

11 3-Audit



Subtotal $71,665

1 Means







Total $133,865

Opinion of Probable Construction CostECM-01.01 (d): Retrofit Lighting Fixtures


Sources


ECM-04.09 (D) MODIFY MIXED AIR TEMPERATURE CONTROL ON

AHU 1-10

MEASURE ECONOMICS SUMMARY ECM # 04.09 (d) Modify Mixed Air Temperature Control on AHU 1-10


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 67,135 $8,056 3,106 $31,062 $39,119 $27,900 0.7

EXISTING CASE The mixed air dampers on all Lakeside AHUs each control to a mixed air temperature set-point that is not directly tied to the discharge air set-point. The constant mixed air and discharge air temperature set-points for each unit in Lakeside are listed in the table below.

Table 9: List of mixed air and discharge air temperature set-points on each AHU

A review of historical trend data indicated that an improper offset between mixed and discharge temperature set-points is causing unnecessary heating and/or cooling in many AHUs. For example, the mixed air set-point on AHU-8 is 59°F, while the discharge air set-point is 55°F, which limits the function of the AHU’s economizer sequence and uses additional chilled water energy to constantly cool the mixed air from 59°F to 55°F at the discharge of the AHU.

Another example is AHU-9, where the mixed air set-point is significantly lower than the discharge set-point. This condition is resulting in unnecessary heating energy during the shoulder seasons since the 49°F mixed air must constantly be heated to 55°F at the discharge of the AHU.

Unit

Existing

MAT

Setpoint

Existing

DAT

Setpoint

AHU-1 53 55

AHU-2 55 55

AHU-3 55 60

AHU-4 55 55

AHU-5 49 55

AHU-6 49 55

AHU-7 52 55

AHU-8 59 55

AHU-9 49 55

AHU-10 48 55


PROPOSED CASE We recommend reconfiguring the mixed air temperature control sequence on all AHUs so that the mixed air temperature set-point continuously resets to track the discharge air temperature set-point, rather than maintaining its own fixed set-point. The following sequence changes are recommended as part of this measure:

During periods when economizer is enabled, the mixed air dampers shall modulate to maintain the active discharge air temperature set-point. If there is not a call for cooling, the dampers shall remain at minimum position.

If the dampers are fully open and there is still a call for cooling (discharge air temperature above set-point), the chilled water valve shall modulate to maintain set-point

When economizer is disabled, the mixed air dampers shall go to minimum position and the chilled water valve shall modulate to maintain the discharge air temperature set-point.

If at any time the mixed air temperature decreases below a low limit set-point (40°F adj.), the mixed air dampers shall modulate to maintain the low limit and an alarm shall be generated at the building automation system.

The proposed sequence may reduce heating and cooling energy consumption during periods when the offset between discharge and mixed air temperature set-points results in unnecessary heating or mechanical cooling energy consumption.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in unnecessary heating and cooling that was observed to occur as a result of the differences in AHU mixed air set-points and discharge air set-points

The energy savings associated with this measure were estimated using a 8,760 hour spreadsheet model that calculated the magnitude of unnecessary preheat energy (Btu/hr) or chilled water energy (Btu/hr) used by each AHU for each hour of the year. This energy was calculated using the following equation:

𝑄 [𝐵𝑡𝑢

ℎ𝑟] = 1.08 ∗ 𝑆𝑢𝑝𝑝𝑙𝑦 𝐴𝑖𝑟𝑓𝑙𝑜𝑤 ∗ (𝑀𝐴𝑇𝑆𝑃 − ( 𝐷𝐴𝑇𝑆𝑃 − 𝛥𝑇𝐹𝑎𝑛,𝑚𝑜𝑡𝑜𝑟))

Where ‘Supply Airflow’ is equal to the supply airflow of each AHU included in this measure and ‘ΔTFan,Motor’ is equal to the average temperature rise across the fan and motor as a result of mechanical and electrical losses to the airstream.

Hot water energy savings were converted to steam savings assuming a steam heating value of 1,000 Btu/lb and a 97% conversion and distribution efficiency.


COST ESTIMATE The costs for this measure include engineering design to create the revised sequence, BAS programming costs, and commissioning.




(978) 208 - 0609


1 2 Programming ea 10 $0 $0 $150 1 4 $6,000 $6,000

2 3 As-built ea 10 $0 $150 1 2 $3,000 $3,000


4

5

Subtotal $15,000

1 Means







Total $27,900

Opinion of Probable Construction CostECM-04.09 (d): Modify Mixed Air Temperature Control on AHU 1-10


Sources


ECM-04.13 (D) INSTALL OCCUPANCY SENSORS IN OPERATING ROOMS

MEASURE ECONOMICS SUMMARY ECM # 04.13 (d) Install Occupancy Sensors in Operating Rooms


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


97,720 $9,772 20,518 $2,462 721 $7,214 $19,448 $115,600 5.9

EXISTING CASE VAV boxes serving the building’s operating rooms currently operate at constant volume and were not observed to have any form of airflow setback. This may be due to the inconsistency in operating room use patterns, which makes it difficult to implement scheduling that could reduce the energy consumption of the equipment serving these areas.

Figure 60 on Page 223 shows a trend screenshot of AHU-9, which serves the operating rooms. The trend shows that over a ten day period, the supply fan speed of the AHU is nearly constant, indicating no airflow set-backs on the downstream terminal devices.

PROPOSED CASE We propose implementing an occupancy schedule in the operating rooms so that between 11:00pm and 5:00am Monday - Sunday, the airflow set-points on VAV boxes serving these areas are reduced to 40% of the existing occupied set-points. As part of this measure, we also propose installing wall switches and occupancy sensors in each of the operating rooms so that schedules can be overridden and airflow can immediately be brought back up to occupied set-points on demand. We do not recommend any adjustments to zone temperature set-points as part of the scheduling, so that operating rooms are maintained at constant temperature and humidity at all times.

ENERGY SAVINGS METHODOLOGY This measure will result in fan, cooling, and heating energy savings during unoccupied periods when airflow to the operating rooms can be reduced, while still maintaining occupied temperature set-points.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. For operating room areas on the second floor, the model’s MIN-FLOW-SCH parameter was modified to reduce minimum VAV box airflow from 100% to 40% between 11:00pm and 5:00am Monday - Friday.


Figure 60: The trend screenshot below shows the supply fan speed (%) for AHU-9 serving the operating rooms between 7/7/2014 and 7/14/2014. The trend indicates that supply airflow set-points at terminal devices are constant and no scheduling is implemented, since AHU-9’s supply fan speed does not fluctuate on a daily basis.


COST ESTIMATE The cost estimate for this measure includes the material and labor cost to install space-mounted override switches, the labor cost to enable turndown on the operating room terminal devices, and the labor cost for control programming and documentation associated with sequence changes.




(978) 208 - 0609


1 3 Room pressurization sensors est 10 $1,500 $15,000 $150 1 8 $12,000 $27,000

2 3 Override Switches ea 10 $800 $8,000 $150 1 8 $12,000 $20,000

3 3 Programming est 10 $0 $150 1 4 $6,000 $6,000

4 3 As-built ea 10 $0 $150 1 2 $3,000 $3,000


Subtotal $62,000

1 Means







Total $115,600

Sources

Opinion of Probable Construction CostECM-04.13 (d): Install Occupancy Sensors in Operating Rooms



ECM-18.00 (D)-1 DISCHARGE AIR TEMPERATURE RESET ON AHU 1-10

MEASURE ECONOMICS SUMMARY ECM # 18.00 (d)-1 Discharge Air Temperature Reset on AHU 1-10


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-41,322 -$4,132 810,228 $97,227 12,559 $125,593 $218,688 $33,700 0.2

EXISTING CASE All air handlers in Lakeside with the exception of AHU-3 have a constant discharge air temperature set-point of 55°F, with AHU-3 having a constant set-point of 60°F. Historical trend data reviews and the original sequence of operation indicate that the discharge temperature set-points do not reset. Trends also show consistent periods during warm weather when approximately 60% of the terminal devices on a given building level were reheating. Figure 61 on Page 227 shows a sample of terminal device reheat valve positions during a week long period in July 2014.

Though trend data was not available for these units during the winter, the patterns observed during spring and summer operation suggest that a much greater amount of reheat may be used during the winter months as a result of the AHU’s fixed discharge set-points.

PROPOSED CASE We propose implementing a discharge air temperature reset schedule in the sequence of operation whereby the set-point is reset up or down based on terminal box reheat valve position. Every five minutes, the BAS will poll the terminal boxes associated with each AHU. If the number of boxes with reheat valves closed is less than a specified threshold (2-3 recommended), then the discharge air temperature set-point would be increased by 0.5°F. If the number of boxes with their reheat valves closed exceeds the set-point, the discharge air temperature would be decreased. The proposed minimum and maximum reset temperatures for the sequence are 55°F and 62°F, respectively.

ENERGY SAVINGS METHODOLOGY An excessively low AHU discharge air temperature requires terminal VAV boxes to use additional reheat energy during mild and cooler weather. Raising the AHU discharge air temperature during these periods can reduce this amount of unnecessary reheat energy used by terminal devices, often without increasing heating energy consumption at the air handler. This is accomplished by modulating the AHU’s mixed air damper to maintain the discharge air temperature set-point without opening the preheat coil during mild weather.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQUEST model. The run was performed on AHU-1, 2, 4, 5, 6, 7, and 8 and changed the following parameters:

Base Case


COOL-RESET-SCH: n/a

Proposed Case

COOL-CONTROL: Reset

RESET-PRIORITY: Simultaneous (Airflow and Temperature)

COOL-MAX-RESET-T: 62°F

COOL-MIN-RESET-T: 55°F


Figure 61: The trend screenshot below shows a sample of VAV box reheat valve positions between 7/23/2014 and 7/30/2014. A majority of reheat valves are open during this period, suggesting there may be an opportunity to implement a discharge air temperature reset. At the timestamp highlighted (7/28/2014 5:00am), four out of eight VAV boxes have reheat valves that are 100% open, and seven out of eight are at least partially open.






(978) 208 - 0609


1 2 Programming ea 10 $0 $0 $150 1 8 $12,000 $12,000

2 3 As-built ea 10 $0 $150 1 2 $3,000 $3,000


4

5

Subtotal $18,000

1 Means







Total $33,700

Sources

Opinion of Probable Construction CostECM-18.00 (d)-1: Discharge Air Temperature Reset on AHU-1-10



ECM-18.00 (D)-2 STATIC PRESSURE RESET ON AHU 1-8

MEASURE ECONOMICS SUMMARY ECM # 18.00 (d)-2 Static Pressure Reset on AHU 1-8


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


198,073 $19,807 49,857 $5,983 -5 -$54 $25,736 $31,700 1.2

EXISTING CASE The sequence of operation for the Lakeside AHUs and their respective terminal boxes is as follows:

The VFD speed shall modulate to maintain a fixed static pressure set-point.

Static pressure set-point is currently a fixed value for all AHUs. The observed static pressure set-point for each AHU is given in the table below:

AHU Units AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8

Existing Static Set-point

" WC 1.75 1.75 1.75 1.5 1.5 1.5 1.75 1.75

VAV box damper position shall modulate between its minimum position and 100% open to maintain the space thermostat set-point. Upon reaching minimum position, if the space temperature remains below the set-point, the reheat valve shall modulate to maintain space temperature.

Though trend data is not available for VAV damper positions, a review of terminal reheat valve positions showed a significant amount of reheat, even through the summer, suggesting that many boxes may be at minimum position.

PROPOSED CASE We propose resetting the duct static pressure set-point on each AHU using a new cascading control algorithm. Every 15 minutes the BAS will perform a damper position “high select” on all VAV boxes served by each of the AHUs. If the average of the top five (user selectable from 1 to 10) “high select” boxes is between 85% and 90% open the system shall hold its current discharge pressure set-point. If the average is below 80% open the BAS logic shall cascade its duct static pressure set-point down to a low of 1.0” WC. If the average of the top five boxes is greater than 90% then the system duct static pressure set-point shall cascade up to a maximum of either 1.25” WC or 1.5” WC, depending on the observed existing case static pressure set-point. The cascading reset loop shall be tuned to avoid unnecessary hunting.


This proposed sequence ensures that sufficient static pressure is maintained in order to supply enough airflow to meet demand, while allowing for “rogue“ non-critical zone(s) that are consistently at or near maximum flow.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run, performed on AHU-1, 2, 3, 4, 5, 6, 7, & 8, changed the supply fan “EIR f(PLR)” performance curve that calculates fan input power as a function of airflow part load ratio. The curve used in the base case is the standard curve available from the eQuest library. A custom curve was developed for the proposed case to model a demand-based duct static pressure. A single curve was applied to all units involved, despite slightly different static pressure set-points and intended resets for some AHUs.

The custom fan curve applied to the proposed case produces an energy input ratio of 0.16 at the maximum turndown of 0.25” WC. The table below shows the existing static pressure set-points on the units involved in this measure, along with their expected minimum static pressure set-points.

Unit

Existing

SP

Setpoint

(in. WG)

Proposed

Minimum SP

Setpoint

(in. WG)

AHU-1 1.75 1.50

AHU-2 1.75 1.50

AHU-3 1.50 1.25

AHU-4 1.50 1.25

AHU-5 1.50 1.25

AHU-6 1.50 1.25

AHU-7 1.75 1.50

AHU-8 1.75 1.50






(978) 208 - 0609


1 2 Programming ea 8 $0 $0 $150 1 8 $9,600 $9,600

2 3 As-built ea 8 $0 $150 1 2 $2,400 $2,400


4

5

Subtotal $16,800

1 Means







Total $31,700

Opinion of Probable Construction CostECM-18.00 (d)-2: Static Pressure Reset on AHU 1-8


Sources


ECM-18.00 (D)-3 RECONFIGURE PREHEAT CIRCULATOR CONTROL

MEASURE ECONOMICS SUMMARY ECM # 18.00 (d)-3 Reconfigure Preheat Circulator Control on AHUs 1-10


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


8,175 $817 0 $0 0 $0 $817 $27,900 34.1

BASE CASE Each AHU in Lakeside has a 3/4 hp preheat circulator for freeze protection and to maintain the necessary flow through the coil. The design information for each circulator pump is given in the table below.

Design Head

Design Flow

Estimated Pump

Efficiency

Estimated Motor

Efficiency

Estimated Input

Power

ft WC gpm % % kW

20 65 65% 90% 0.561

The circulators were observed to operate based on outside air temperature, including the unit serving AHU-10, which acts as a back-up to AHU-9 and typically does not operate. It was noticed that the outside air temperature set-points were different between nearly all of the pumps in the building. The table below summarizes the outdoor air temperature enable set-points for each AHU’s preheat circulator.

AHU AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 AHU-9 AHU-10

Pump Enable

OAT 55°F 55°F 55°F 47°F 47°F 47°F 48°F 50°F 50°F

PROPOSED CASE We recommend modifying the existing preheat circulator sequence of operation by enabling pumps for operation based on heating load instead of outdoor air temperature. In the proposed case, pumps would start and run when the discharge or preheat discharge air temperature control loops call for heating. In order to maintain freeze protection on these AHUs, we recommend implementing an outdoor air temperature override so that pumps are enabled below 35°F. This measure will reduce the energy consumption of the circulators without have adverse impacts on equipment freeze protection.


ENERGY SAVINGS METHODOLOGY This measure will result in energy savings due to a reduction in run hours of the dedicated AHU heating coil circulator pumps. Savings were calculated using an 8,760 hour spreadsheet using TMY3 (Typical Meteorological Year 3) weather data for Worcester, MA. Energy savings are derived from the reduction in preheat circulator run hours during periods when the outdoor air temperature is below the existing enable set-point but preheat is not necessary to meet discharge air temperature set-points.

In the base case model, pump run hours were limited to when the outdoor air temperature was below the existing enable set-point. The proposed case model recalculated pump run hours, limiting operation only to periods when the outdoor air temperature was low enough to require the heating coil valve to be open. This outdoor air temperature threshold was different for each AHU due to differences in minimum outdoor air ratios, observed discharge air temperatures, and return air temperatures.






(978) 208 - 0609


1 2 Programming ea 10 $0 $0 $150 1 4 $6,000 $6,000

2 3 As-built ea 10 $0 $150 1 2 $3,000 $3,000


4

5

Subtotal $15,000

1 Means







Total $27,900

Opinion of Probable Construction CostECM-18.00 (d)-3: Reconfigure Preheat Circulator Control on AHU 1-10

Sources



ECM-18.00 (D)-4 OPTIMIZE HOT WATER SUPPLY TEMPERATURE RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (d)-4 Optimize HWST Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


4 $0 0 $0 547 $5,475 $5,475 $8,200 1.5

EXISTING CASE The hot water converters in Lakeside serve air handlers, VAV reheats, and baseboard radiators. A review of trend data showed that the hot water supply temperature set-point resets based on outdoor air temperature with the set-point ranging between 190°F and 180°F. The original Siemens controls submittal for the HW converters showed a reset schedule ranging between 190°F and 150°F.

PROPOSED CASE We recommend revising the existing hot water reset to increase the system’s efficiency during periods of low thermal load. During the summer months, a hot water supply temperature of 180°F may not be necessary to satisfy terminal reheat loads. The table below summarizes the proposed reset parameters.

Outdoor Air Temperature HWST Set-point

0°F 190°F

60°F 150°F


The energy savings associated with this measure were estimated using a parametric run of the baseline eQUEST model. The run was performed on the “HW Loop” system which models the building’s hot water loop using estimated piping lengths and dimensions based on available drawings. The following parameters were changed as part of the parametric run.


Base Case







Proposed Case












(978) 208 - 0609


1 2 Programming ea 3 $0 $0 $150 1 4 $1,800 $1,800

2 3 As-built ea 1 $0 $150 1 4 $600 $600


4

5

Subtotal $4,200

1 Means







Total $8,200

Labor

Opinion of Probable Construction CostECM-18.00 (d)-4: Optimize Hot Water Supply Temperature Reset

General Materials

Sources


ECM-18.00 (D)-5 REPLACE AHU-4 RETURN TEMPERATURE SENSOR

MEASURE ECONOMICS SUMMARY ECM # 18.00 (d)-5 Replace AHU-4 Return Temperature Sensor


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 1,074 $129 6 $55 $184 $3,900 21.2

EXISTING CASE Trend data showed that the return air temperature sensor on AHU-4 was out of calibration, reading approximately 2°F higher than the actual expected temperature. Figure 62 on Page 240 illustrates the calibration issue. When the unit is commanded to minimum outside air, the mixed air temperature is not between the return and outdoor air temperature measurements, as would be expected. However, when the unit is commanded to 100% outside air, the outside and mixed air temperatures are essentially equal, as expected. This suggests that the return air temperature sensor is out of calibration since the outdoor air mixed air temperature sensors appear to be calibrated relative to each other.

The return air sensor calibration issue is affecting the efficiency of economizer sequence by enabling economizer during periods when the outdoor air temperature and enthalpy are greater than the return conditions. This may result in excess chilled water energy consumption during periods when the outdoor air temperature is within approximately 2°F of the return temperature.

PROPOSED CASE We recommend replacing the return air temperature sensor on AHU-4 for efficient economizer operation.

ENERGY SAVINGS Energy savings are derived from the reduction in mechanical cooling energy that is used when economizer was inappropriately enabled in the existing case as a result of the return air temperature reading lower than actual.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-4 and changed the economizer’s comparative enthalpy enable offset (Outdoor Air Enthalpy < Return Air Enthalpy) from -1.0 Btu/lb in the base case to 0 Btu/lb in the proposed case. The -1.0 Btu/lb existing case offset represents the enthalpy differential corresponding to the return air temperature sensor drift of 2°F at an average outdoor air relative humidity of 65%. By implementing a negative offset in the base case eQuest model, the economizer sequence is allowed to operate when the outdoor air


enthalpy is greater than the return air enthalpy by approximately 1.0 Btu/lb, which can result in additional mechanical cooling energy consumption.


Figure 62: The trend screenshot below shows two periods when the mixed air damper is at minimum position, but the mixed air temperature is lower than both the return and outdoor air temperature measurements. This suggests a potential sensor calibration issue.


COST ESTIMATE The costs for this measure include the labor and material cost for sensor recalibration and or replacement for the return air temperature sensor on AHU-4.




(978) 208 - 0609


1 3 Replace return air sensor ea 1 $600 $600 $150 1 4 $600 $1,200

2 3 Calibration ea 1 $0 $150 2 1 $300 $300


4

5

Subtotal $2,100

1 Means







Total $3,900

Opinion of Probable Construction CostECM-18.00 (d)-5: Replace AHU-4 Return Air Temperature Sensor


Sources


ECM-18.00 (D)-6 REPLACE LEAKING CHW VALVE ON AHU-2

MEASURE ECONOMICS SUMMARY ECM # 18.00 (d)-6 Replace Leaking CHW Valve on AHU-2


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 131,378 $15,765 1,651 $16,508 $32,273 $8,150 0.3

EXISTING CASE The chilled water valve on AHU-2 is leaking by, with a 5oF temperature drop observed between the mixed and discharge air temperature when both the heating and cooling valves were commanded fully closed. This is resulting in wasted cooling energy as well as an additional simultaneous load on the heating coil during certain parts of the year. The table below shows AHU-2 specifications.

HVAC

Type

Supply

Fan HP

Supply

Fan Qty

Return

Fan HP

Return

Fan Qty

Calculated

Supply Air Flow

Unit MAT

Set-point

Unit DAT

set-point

VAV 75 HP 1 25 HP 1 40,000 CFM 55oF 55oF

Figure 63 on Page 244 illustrates the conditions that indicate a potential leaking chilled water valve.

PROPOSED CASE We recommend replacing the chilled water valve to eliminate leak-by and reduce the associated unnecessary mechanical cooling and preheat energy consumption.

ENERGY SAVINGS This savings associated with this measure were calculated using a customized, hourly spreadsheet model and hourly TMY3 weather data from Worcester, MA. The magnitude of the chilled water valve leakby was calculated for each hour of the year using historical trend data and the resulting excess cooling load was calculated using the formula below:


Where,


on both the preheat and chilled water coils when cooling is not needed.

CFMSupply = Total supply airflow


∆Tcooling = 𝑇𝐷𝐴 < 𝑇𝑀𝐴 + 𝑇𝑆𝐹 = Magnitude of the temperature drop across the cooling coil





∆𝑇𝑆𝐹 = 2545 ∗ [𝑃 (

1𝐸𝑀

− 1) + 𝑃(1 − 𝐸𝐹)]

1.08𝑄

Where, ΔTSF = Temperature Rise across Motor and Fan 2545 = Btu/hp P = Shaft Power (bhp) EM = Motor Efficiency EF = Fan Mechanical Efficiency 1.08 Btu/hr-CFM-°F Q = Air Flow Rate (CFM)


No savings during periods when the mixed air temperature is greater than 55oF, as it is assumed that the mechanical cooling will be needed to meet this discharge air temperature set-point

Simultaneous load on the cooling coil is equal in magnitude to the leakby load on the cooling coil.

In both the base & proposed case, the unit operates with the minimum outside air percentage determined numerically from trend data, approximately 50%.


Figure 63: The trend screenshot below shows the potential chilled water valve leak-by on AHU-2. During periods when the chilled water valve position (PINK) and preheat valve position (ORANGE) are both 0% (as indicated by the periods highlighted in gray), the discharge air temperature (BLUE) is less than the mixed air temperature (RED). Typically, the temperature difference is between 4°F and 7°F.


COST ESTIMATE The estimated costs for this measure includes an allocation for the replacement of the valve bodies, valve actuators or controls, functional testing of valves to determine what part of the device has failed, and commissioning of each valve to verify correction operation after repair.




(978) 208 - 0609


1 3 As-Builts ea 1 $0 $150 1 6 $900 $900




5 3 DDC Control Point ea 1 $250 $250 $150 1 4 $600 $850

Subtotal $4,150

1 Means







Total $8,150


Sources

Opinion of Probable Construction CostECM-18.00 (d)-6: Replace Leaking CHW Valve on AHU-2

246 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Lazare Research Building

LAZARE RESEARCH BUILDING (LRB) EXECUTIVE SUMMARY TABLE

The cost savings figures in the summary table on the following page assume the following utility rates: $0.10/kWh, $0.12/ton-hour, $10.00/Mlb.


ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive

- kWh ton-hr Mlb $ $ yrs

1.01 (e) Lighting Retrofit 1,270,300 0 0 $127,030 $302,250 2.4

03.00 (e) Replace Cage Washer Pump Motors 1,252 0 0 $125 $11,500 91.9

03.01 (e)-1 EC Motors on Bio-Safety Cabinet Fans 58,412 0 0 $5,841 $167,148 28.6

03.01 (e)-2 EC Motors on DHW Circulators 35,222 0 0 $3,522 $40,544 11.5

03.01 (e)-3 EC Motors on AHU-10 & 11 23,063 4,527 27 $3,120 $16,500 5.3

03.01 (e)-4 Retrofit RO Water Pumps with VFDs 69,848 0 0 $6,985 $42,770 6.1

04.02 (e) Comparative Enthalpy Economizer on AHU-9 425 2,449 0 $337 $10,650 31.6

04.09 (e)-1 Scheduling and Set-points on AHU-9 Zones 13,052 6,278 325 $5,306 $39,650 7.5

04.09 (e)-2 Reprogram AHU-7 Preheat Control Sequence 23,886 269,211 2,828 $62,976 $10,000 0.2

04.09 (e)-3 Reduce Air Change Rates in Labs 12,778 129,252 6,732 $84,109 $682,450 8.1

04.09 (e)-4 Hot Water Loop Differential Pressure Reset 940 0 34 $431 $10,000 23.2

04.09 (e)-5 Process CHW Loop Differential Pressure Reset 7,874 0 0 $787 $20,500 26.0

04.11 (e)-1 Heat Recovery on Make-up Air Units (AHU 1-6) -300,403 9,269 20,367 $174,743 $995,504 5.7

04.11 (e)-2 Install Passive Chilled Beams in Labs 405,347 233,302 2,120 $89,734 $1,862,993 20.8

18.00 (e)-1 Static Pressure Reset 321,723 89,563 -320 $39,718 $54,000 1.4

18.00 (e)-2 Discharge Air Temperature Reset -2,510 462,855 -693 $48,365 $17,200 0.4

18.00 (e)-3 Replace Leaking Preheat Valves 0 168,570 2,141 $41,634 $19,050 0.5

18.00 (e)-4 Replace Leaking Chilled Water Valve 0 41,958 533 $10,363 $10,425 1.0

18.00 (e)-5 Reduce AHU-9 Minimum Outdoor Air 16,536 14,135 1,347 $16,818 $8,500 0.5

18.00 (e)-6 Reprogram AHU-10, 11 Zone Temperature Set-points 618 3,761 20 $716 $3,900 5.4

18.00 (e)-7 Replace Preheat Face/Bypass Damper Actuators 235,436 7,635 3,529 $59,754 $14,400 0.2

18.00 (e)-8 Exhaust Fan Static Pressure Reset 213,924 0 0 $21,392 $6,600 0.3

18.00 (e)-9 Temperature Set-backs in Lab Corridors 3,465 15,823 954 $11,782 $19,500 1.7

18.00 (e)-10 Hot Water Supply Temperature Reset -956 0 4,304 $42,940 $6,600 0.2

TOTALS 2,410,232 1,458,588 44,248 $858,530 $4,372,635 5.1



The University of Massachusetts, Aaron Lazare Medical Research Laboratory Building is a 10 story, 398,697 ft2 facility housing teaching and research laboratories, a vivarium, supporting offices, and support equipment facilities. The vivarium is located on Level 1, staff offices are located on the east side of each floor, the main mechanical rooms are located on Level 10 (penthouse), and laboratories located on Levels 2 - 9. A kitchen and cafeteria are also located on level 1 which are generally unused since the opening of the Sherman Center’s cafeteria.

LABORATORIES Conditioned air to the laboratories is provided by six (6), 100% outside-air AHUs located in the penthouse. Each air handler is equipped with two (2) supply fans. The two (2) fans are equipped with variable frequency drives (VFDs) controlling static pressure in the supply ducts. These six (6) AHUs are manifolded into two (2) separate systems, with AHUs 1, 4 and 5 serving Levels 2-5, and AHUs 2, 3, and 6 serving Levels 6-9.

Exhaust for the laboratories is provided by (18) rooftop exhaust fans, with three (3) ancillary, in-line exhaust fans providing some local exhaust. The eighteen (18) major exhaust fans are combined into groups of 3 (i.e. EX1: 1a, 1b, and 1c.... EX2: 2a, 2b, 2c... etc...) and are manifolded immediately below the roof line to form six (6) major vertical exhaust duct drops. These six (6) duct drops are again combined into groups of three (3) to serve two (2) separate systems (levels 2-5, or 6-9). The numbering of the groups corresponds to the AHU numbering (EX 1, 4 and 5 serving levels 2-5, and EX 2, 3, and 6 serving levels 6-9). Each of the three (3) duct drops are cross-connected on each level that they serve.

The ventilation systems for the laboratories are designed to operate as a variable volume system, with once through air (100% outside air). The laboratory-level air delivery is temperature dependent (load driven) for 98% of the laboratories (3 laboratories on the 8th level vary according to fume hood sash positions).

There are several different types of local exhaust ventilation systems:

88 constant volume laboratory fume hoods

24 variable volume laboratory fume hoods

Miscellaneous bathroom exhausts and general exhaust for offices and hallways.

24 canopy exhausts (glass-wash areas).

VIVARIUM (ANIMAL ROOMS) Conditioned air to the vivarium is provided by two (2), 100% outside-air AHUs (AHU 7 & 8) located in first level mechanical room. Each air handler is equipped with two (2) supply fans. The two (2) fans in are equipped with variable frequency drives (VFDs) controlled by feedback


from static pressure sensors in the supply ducts. Each of the AHUs serves half of the vivarium and has a cross connection in the event that one AHU needs to be shut down for maintenance.

Exhaust for the vivarium is provided by six (6) rooftop exhaust fans, with one (1) other in-line exhaust fan providing exhaust to the cage wash area. The six (6) major exhaust fans are combined into groups of three (EX7: 7a, 7b, and 7c.... EX8: 8a, 8b, 8c) and are manifolded immediately below the roof line to form two (2) major vertical exhaust duct drops. These two (2) duct drops serve two (2) separate areas of the vivarium.

The ventilation systems for the vivarium area are designed and operate as a constant volume system with once through air (100% outside air). The effective design air change rate for the vivarium is 17.6 ACH. In May 2013, the Vivarium’s air change rate was reduced to an average of 13.4 ACH as part of a wider airflow reduction project in the laboratory areas of the facility.

OFFICE & SUPPORT AREAS Conditioned air to the offices is provided by AHU-9 and is located in the penthouse. This AHU is coupled with a return air fan (RF-9). RF-9 returns air back from the space to the intake of AHU-9 for re-conditioning and re-circulation. AHU-9 must provide a minimal amount of fresh or outside air makeup, therefore only a percentage of the air from RF-9 can be re-circulated. The two fans on this unit are equipped with variable frequency drives (VFDs) and are controlled by feedback from static pressure sensors in the duct. This AHU serves the offices and hallways on the east side of levels 2-9 and the conference rooms and cafeteria on the 1st level.

A description of the existing lighting systems in the building can be found in the base case description of ECM-01.01-1: Lighting Retrofit.



ENERGY USE GRAPHS

ELECTRICITY Figure 64 on the following page shows electricity use for the LRB for fiscal years 11 – 14. It can be seen that electricity use is fairly consistent throughout fiscal year 11 and 12, with slight variations between the years likely due to weather effects. There is significantly higher usage in fiscal year 2013, possibly due to energy use resulting from the construction of the nearby Sherman Center.

Figure 65 shows the electric use averaged over fiscal years 2011-2012, taken as the utility use baseline for energy model calibrations. Fiscal year 2013 was excluded due to the data being abnormally high, and fiscal year 2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 64: LRB monthly electricity use (kWh) for Fiscal Years 2011 - 2014.

Figure 65: LRB baseline electricity use (kWh) profile, using averaged monthly data from Fiscal Years 2011 - 2012.

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000


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)

LRB Electric Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

0

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1,000,000

1,500,000

2,000,000

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Ele

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LRB Baseline Electric Use

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-12)


STEAM Figure 66 shows the monthly steam consumption for fiscal years 11 – 14. It can be seen that steam use is fairly consistent throughout fiscal year 11 and 12, with slight variations between the two years likely due to weather effects. There is significantly higher usage in fiscal year 2013, which may be due to energy use resulting from the construction of the nearby Sherman Center. In fiscal year 2014, some pronounced variations can be seen between months, possibly due to differentials in meter read dates or meter calibration.

Figure 67 shows the steam use averaged over fiscal years 2011-2012, taken as the utility use baseline for energy model calibrations. Fiscal year 2013 was excluded due to the data being abnormally high, and fiscal year 2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 66: LRB monthly steam energy use (Lbs) for Fiscal Years 2011 - 2014.

Figure 67: LRB baseline steam energy use (Lbs) profile, using averaged monthly data from Fiscal Years 2011 - 2012.

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LRB 50# Steam Use FY 11 - FY 14

FY 11

FY 12

FY 13

FY 14

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LRB Steam Use FY 11 - FY 13

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-12)


CHILLED WATER Figure 68 shows the LRB CHW use from fiscal years 11 – 14. Differences in CHW use can be seen between years, with data from FYs 2011-2012 showing the most consistency. In fiscal year 2013 and 2014, some pronounced variations can be seen between months, possibly due to differentials in meter read dates. Data use in fiscal year 2013 is also higher during summer months, possibly due to energy use resulting from the Sherman center construction.

Figure 69 shows the CHW use averaged over fiscal years 2011-2012, taken as the utility use baseline for energy model calibrations. Fiscal year 2013 was excluded due to the likely impact of the Sherman center construction, and fiscal year 2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 68: LRB monthly chilled water energy use (ton-days) for Fiscal Years 2011 - 2014.

Figure 69: LRB baseline chilled water energy use (ton-days) profile, using averaged monthly data from Fiscal Years 2011 - 2012.

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LRB Baseline CHW Use

FY 11

FY 12

FY 13

FY 14

Baseline (FY11-12)


BENCHMARKING

BENCHMARKING SUMMARY TABLE The table on the following page summarizes the annual energy consumption and performance metrics for the facility. This was done to provide a clear representation of the actual site and estimated equivalent source energy consumption for benchmarking and also for evaluation with energy savings opportunities. Energy use data for fiscal years 2011 – 2012 is shown in the table, along with an average of data from the two fiscal years.


Energy Use


Performance Ratings









ft2 FY kWh ton-hrs klbs

kWh

/ft2

W

/ft2

kBtu

/ft2

kBtu

/ft2

kWh

/ft2

kBtu

/ft2

kBtu

/ft2

kWh

/ft2

kBtu

/ft2

kBtu

/ft2

kBtu

/ft2

FY11 16,537,140 2,282,952 81,083 41.5 4.74 141.7 69 3.2 8.2 204 0 254 414 415

FY12 16,545,070 2,711,040 90,563 41.5 4.74 141.7 82 3.8 9.7 227 0 284 451 449

2 Year Avg. 16,541,105 2,496,996 85,823 41.5 4.74 141.7 75 3.5 9.0 215 0 269 432 432

UMass Medical Center Lazare Research Building Energy Use Data

Steam Total

Source Source

CHW

BLDG INFO ENERGY USE PERFORMANCE RATINGS

Floor

AreaFiscal Year Electricity CHW

50#

SteamElectricity

398,370


BENCHMARKING COMPARISON The table below benchmarks the LRB’s total source energy usage intensity (kBtu/ft2) against three other academic/research laboratories in New England, as well as a sample of facilities similar to the LRB available through the Labs21 database. The criteria used for the Labs21 benchmark sample are:

Lab Area / Gross Area Ratio: 0.60 - 0.90

Occupancy hours per week: Standard (<= 80 hours)

Lab Type: Chemical, Biological, Chemical/Biological, Combination/Others

Lab Use: Research/Development, Teaching, Combination/Others

Climate Zone: 5A (Cool - Humid) The table also compares the LRB’s building characteristics such as gross floor area and estimated laboratory floor area ratio to the other buildings.

In order to compare each of the buildings’ energy use benchmarks, all electricity, chilled water, and steam energy consumption was converted to estimated equivalent source energy (kBtu). For example, Academic Lab 1 is supplied steam and chilled water from district systems, but Academic Labs 2 and 3 have on-site chiller plants and district steam. As a result, a direct site electricity use comparison between these buildings and the LRB could be misleading.

NEW ENGLAND ACADEMIC LABS

The table shows that the LRB’s source energy usage intensity (EUI) is higher than all three of the comparison buildings, including the Academic Lab 3 which has a similar ratio of floor area utilized as laboratory space (80%). On average, the LRB’s source EUI is 30% higher than the three comparison buildings and is 75% higher than Academic Lab 3, which may be driven by the amount of 100% outdoor air systems in the LRB and the lack of any heat recovery. However, since Academic Labs 1 and 2 have a significantly lower ratio of laboratory floor area compared to the LRB, it is logical that their source EUI is lower.

Two additional site benchmarks are included in the table: Site Electricity Use Intensity (kWh/ft2) and Average Electric Demand (W/ft2). Average Electric Demand is calculated by dividing the building’s annual electricity consumption by 8,760 hours/year, and multiplying by 1000 W/kW to determine the annual average demand at the facility. Both of these benchmarks compare

ft2 132,998 178,612 81,304 130,971 - 398,370

% 40% 40% 80% 53% 72% 80%

kBtu/ft2 343 396 248 329 596 432

kWh/ft2 30.2 32.5 26.7 29.8 33.4 41.5

W/ft2 3.4 3.7 3.0 3.0 3.8 4.7

Units

New

England

Academic

Lab 1

New

England

Academic

Lab 2

New

England

Academic

Lab 3

Average

of

Lab 1-3

Lazare

Research

Building

Gross Floor Area

Ratio of Laboratory Floor Area

Source Energy Use Intensity (EUI)

Site Electricity Use Intensity

Average Electric Demand

Labs 21

Benchmark

Sample

Average


only the average annual electricity consumption in each of the buildings. Although Academic Lab 2 and 3 have electric chiller plants included on the building metering and the LRB does not, the LRB intensity and average demand is still greater that all three labs. This may be the result of the amount of floor area dedicated to laboratory space in the LRB, or could be driven by the types of research and experimentation ongoing at each of the buildings.

LABS21 BENCHMARKING SAMPLE

The average source EUI of the Labs21 benchmarking sample of buildings is 38% greater than the source EUI of the LRB with a comparable ratio of laboratory floor area. However, the average quantity of occupancy hours among the building sample was 60 hours/week, which is higher than the typical occupancy at LRB. This may be one of the reasons why the LRB has a lower source EUI compared to the sample average. The data from individual buildings included in the Labs21 average is included in the table below, and shows significant variability among buildings.

Labs21 Benchmarking - Building Results

Laboratory Type Benchmarking

Year Source EUI

kBtu/ft2 Lab Floor

Area Occupancy

Hours / Week Climate

Zone

ChemicalBiological 2011 361.25 60% 80 5A


CombinationOthers 2010 448.48 65% 60 5A

Chemical 2007 501.9 66% 50 5A








Chemical 2002 357.51 71% 72 5A

Biological 2007 825.77 72% 30 5A

Chemical 2011 687.82 74% 40 5A

Biological 2012 601.9 75% 40 5A






Chemical 2008 801.47 80% 60 5A

Chemical 2011 1498.23 80% 60 5A

Averages 596.1 72% 59.6



Energy and cost savings were estimated using an existing eQuest model of the facility originally developed by Andelman & Lelek and modified to reflect current equipment characteristics, schedules, and internal loads. The model used the Typical Meteorological Year Three (TMY3) weather file for Worcester, MA and was calibrated against monthly electricity use over a three year period from July 2010 – July 2013. The model was also calibrated for chilled water and steam use using monthly data obtained from the UMass central plant staff. The charts below compare the baseline utility use and the calibrated eQuest model predicted utility use.

Figure 70: LRB eQuest model electricity use calibration chart. The baseline monthly electricity use utility data is shown in blue and the eQuest model predicted monthly electricity consumption is shown in red

0

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)


UtilityData

eQUESTOutput


Figure 71: LRB eQuest model chilled water calibration chart. The baseline monthly chilled water utility data is shown in blue and the eQuest model predicted monthly chilled water energy consumption is shown in red.

Figure 72: LRB eQuest model steam calibration chart. The baseline monthly steam utility data is shown in blue and the eQuest model predicted monthly steam consumption is shown in red.

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The table below summarizes the annual end-use energy distribution for electricity, steam, and chilled water at the facility as calculated by the baseline eQuest model. The pie chart below illustrates the baseline eQuest model’s electricity end use using the figures shown in the table.

The “Miscellaneous Equipment” category in the table below can include the following equipment types: plug loads (such as laboratory equipment, computers, freezers, refrigerators, bio-safety cabinet fans), transformer losses assigned to the building, and elevators. The relatively high fraction of miscellaneous loads in the LRB (41% of annual electricity consumption) can be attributed to the large amount of plug loads, especially the high density ultra-low temperature (ULT) freezers.

The following parameters were used to model the estimated miscellaneous loads in the building, based on information gathered during walkthroughs and historical whole-building electricity use:

1. Bay Laboratory/Alcove Plug Loads: 1.8 W/ft2

2. Laboratory Corridor Plug Loads: 8.0 W/ft2 (high density of ULT freezers)

3. Average Transformer Losses: 40 kW

4. Peak Elevator Load: 35 kW


1. Office, Corridor, and Core Laboratory Lighting Power Density: 1.1 W/ft2

2. Bay Laboratory and Alcove Lighting Power Density: 1.4 W/ft2

Table 10: LRB eQuest model’s annual energy end-use for each meter (electricity, steam, and chilled water).

End Use

Electricity Steam Chilled Water

kWh Mlbs ton-hours


Task lighting end-use energy 0 0 0

Miscellaneous Equipment 7,576,124 15,965 138,980






Refrigeration 0 0 0

Heat Pump 0 0 0

Hot Water 0 0 0

Exterior 0 0 0

TOTALS 17,182,950 79,943 3,122,351


Figure 73: Pie chart showing LRB eQuest model’s annual electricity end use breakdown.

Area Lighting 16%

Miscellaneous Equipment

41%

Pumps and Auxiliary

4%

Ventilation Fans 39%

Baseline Model Annual Electricity End Uses


ECM-01.01 (E) : LIGHTING RETROFIT

MEASURE ECONOMICS SUMMARY ECM # 1.01 (e) Lighting Retrofit


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


1,270,300 $127,030 0 $0 0 $0 $127,030 $302,250 2.4

BASE CASE The facility’s lighting consists primarily of two-lamp, 26 Watt compact fluorescent lamps (CFLs) in recessed and pendant cans, 1’ by 24’ two-lamp 32 Watt T8 fixtures (labs), and 2’ by 8’ two- and four-lamp 32 Watt T8 fixtures. The remaining 4’ fluorescents consist of 2’ by 4’ one-, three-, and four-lamp 32 Watt T8 fixtures. In addition, there is also a significant quantity of 2’ by 2’ two- and three-lamp 17 Watt T8 fluorescent fixtures, and 50 and 60 Watt incandescent flood lights in both recessed and pendant cans.

The remaining lighting consists of a small amount of 1’ by 2’ one lamp 17 Watt T8 and 1’ by 4’ one lamp 32 Watt T8. The lens type on most of the fluorescent fixtures was found to be prismatic, parabolic, or volumetric. With the exception of the first floor lobby and the large common area adjacent to the lobby, the recessed and pendant CFL and incandescent floods lights do not have lenses.

UMass recently upgraded lighting in three buildings on campus, with the entire project consisting of approximately 10,000 28 Watt T8 lamps. An estimated 2,400 of these were dedicated to the LRB. UMass staff re-lamped a large portion of the halls, entryways, and common area fluorescent fixtures that remain on during all hours of the year.

PROPOSED CASE This measure proposes to upgrade existing lighting lamps and ballasts to newer high efficiency units where applicable. Refer to the Opinion of Probable Cost Table on the following page for a breakdown of proposed equipment types and quantities. We recommend replacing 4’ 32 Watt T8 lamps with high efficiency 28 Watt lamps and NEMA Premium (NP) electronic ballasts. We also recommend replacing CFLs and incandescent floods with LED lamps and installing occupancy sensors in some areas of the building. The recommendations do not include fixture upgrades or replacement in an effort to present a more cost effective retrofit approach.



ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in electricity use by replacing existing lighting fixtures, lamps, and ballasts with high efficiency equipment. Savings were estimated using a custom spreadsheet model that calculates existing and proposed case annual energy consumption based on the power consumption of each lighting fixture and the associated annual run hours.

ASSUMPTIONS An audit was performed on the first and second floors of the building to record fixture types and quantities (with the exception of areas that were inaccessible). Since Levels 3 - 9 are very similar in floor plan layout and space utilization to the second floor, a walk-through of the higher floors was performed to only to confirm floor plan information and note any significant differences. Level A (basement), the Penthouse (Level 10), and interstitial space were inaccessible, but the types of fixtures, lamps, and their quantity were captured from the lighting plans and are included in this measure’s scope.


COST ESTIMATE


100 Burtt Rd. Ste. 212 Address: Lazare Building Estimated By: KK


(978) 208 - 0609


1 3-Audit



2 3-Audit



Ballast (Labs) ea 295 $225 $66,375 $0 0 0 $0 $66,375

3 3-Audit



Ballast ea 737 $55 $40,535 $0 0 0 $0 $40,535

4 3-Audit



Ballast ea 64 $55 $3,520 $0 0 0 $0 $3,520

5 3-Audit

Retrofit - 1 Lamp 4 foot 32 watt T8 with NP

Ballast with 1 Lamp 4 foot 28 watt T8 with NP

Ballast ea 16 $45 $720 $0 0 0 $0 $720

6 3-Audit



Ballast ea 29 $60 $1,740 $0 0 0 $0 $1,740

7 3-Audit



Ballast ea 32 $65 $2,080 $0 0 0 $0 $2,080

8 3-Audit

Retrofit - 4 Lamp 8 Foot 32 Watt T8 with NP

Ballast with 4 Lamp 8 Foot 28 Watt T8 with NP

Ballast ea 48 $130 $6,240 $0 0 0 $0 $6,240

Opinion of Probable Construction CostECM-01.01-1: Lighting Retrofit




100 Burtt Rd. Ste. 212 Address: Lazare Building Estimated By: KK


(978) 208 - 0609


9 3-Audit



Ballast ea 4 $45 $180 $0 0 0 $0 $180

10 3-Audit



Ballast ea 226 $55 $12,430 $0 0 0 $0 $12,430

11 3-Audit



Ballast ea 48 $60 $2,880 $0 0 0 $0 $2,880

12 3 Audit

Replace 60 Watt Incandescent Flood lamps

with 25 Watt LED's ea 265 $5 $1,325 $0 0 0 $0 $1,325

13 3 Audit

Replace 50 Watt Incandescent Flood lamps

with 25 Watt LED's ea 24 $5 $120 $0 0 0 $0 $120

14 3 Audit Wall Switch Occupancy Sensors ea 172 $90 $15,480 $0 0 0 $0 $15,480

Subtotal $162,350

1 Means







Total $302,250

Opinion of Probable Construction CostECM-01.01-1: Lighting Retrofit


Sources


ECM-03.00 (E) REPLACE CAGE WASHER PUMP MOTORS

MEASURE ECONOMICS SUMMARY ECM # 03.00 (e) Replace Cage Washer Pump Motors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


1,252 $125 0 $0 0 $0 $125 $11,500 91.9

BASE CASE The facility’s two animal cage washers feature a total of six 3600 rpm water pumps, each rated at 7.5 hp and 87.5% nominal efficiency. Each washer is estimated to operate for five cycles per day, each lasting one hour, seven days per week.

PROPOSED CASE This measure proposes to replace the existing TEFC cage washer pump motors with premium efficient units, which would have NEMA nominal efficiencies of 89.5% or greater. Since it has a long payback, this measure could be considered at end-of-life replacement as cage washer pump motors fail or are scheduled for preventative maintenance replacement.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in pump energy that is used by improving the full load efficiency of the motors.

The energy savings associated with this measure were estimated using spreadsheet calculation comparing the full load input power of the existing motors at 87.5% efficiency to the proposed motors at 89.5% efficiency. Annual run hours were estimated assuming seven running hours per day on each pump motor, and five days of operation per week, based on information provided by facilities staff.




100 Burtt Rd. Ste. 212 Address: LRB Estimated By: SD


(978) 208 - 0609


1 2 7.5 hp Motor ea 6 $900 $5,400 $150 1 2 $1,800 $7,200

2 3 As-built ea 1 $0 $150 1 0 $0 $0


Subtotal $7,500

1 Means







Total $11,500

Opinion of Probable Construction Cost ECM-03.00 (e): Replace Cage Washer Motors


Sources


ECM-03.01 (E)-1 EC MOTORS ON BIO-SAFETY CABINET FANS

MEASURE ECONOMICS SUMMARY ECM # 03.01 (e)-1 EC Motors on Bio-Safety Cabinet Fans


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


58,412 $5,841 0 $0 0 $0 $5,841 $167,148 28.6

BASE CASE The building has an estimated 142 biosafety cabinets that are used as enclosed, ventilated laboratory workspaces for safely handling materials contaminated (or potentially contaminated) with pathogens requiring a defined biosafety level. Each cabinet features a constant speed blower fan that recirculates filtered air from within the cabinet to the laboratory. A sample survey of cabinets found that their blower fan motors are typically either 1/3 or 3/4 hp permanent split capacitor (PSC) type, which can have full load efficiencies of 65% or lower.

PROPOSED CASE This measure proposed to replace the existing biosafety cabinet blower fan motors with high efficiency electronically-commutated (EC) motors. These direct current motors have higher full- and part-load efficiencies. We do not recommend including variable speed control due to the higher first cost associated with the necessary sensors and programming.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan energy that is used by improving the full load efficiency of the blower motors.

The energy savings associated with this measure were estimated using spreadsheet calculation comparing the full load input power of the existing PSC motors (assuming 60% average efficiency) to the proposed EC motors (assuming 93% average efficiency). The quantity and annual run hours of bio-safety cabinets in the building were estimated based on a walkthrough of typical laboratories on the 2nd, 4th, and 8th floors, as well as information provided by facilities staff. Annual run hours were estimated assuming eight running hours per day on each cabinet fan and five days per week of operation. A diversity factor of 75% was applied to the savings estimate to account for cabinets which may not be used on a given day.






(978) 208 - 0609


1 3 1/3 hp EC Motor ea 85 $435 $36,975 $150 1 2 $25,500 $62,475

2 3 3/4 hp EC Motor ea 57 $464 $26,448 $150 1 2 $17,100 $43,548

3 4 As-built ea 1 $0 $150 1 0 $0 $0


Subtotal $111,348

1 Means







Total $167,148

Opinion of Probable Construction CostECM-03.01 (e)-1: EC Motors on Bio-safety Cabinet Fans


Sources


ECM-03.01 (E)-2 EC MOTORS ON DHW & NON-POTABLE WATER

CIRCULATORS

MEASURE ECONOMICS SUMMARY ECM # 03.01 (e)-2 EC Motors on DHW Circulators


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


35,222 $3,522 0 $0 0 $0 $3,522 $40,544 11.5

BASE CASE Domestic hot water (DHW) is circulated throughout the building via a constant speed in-line pump located in the basement. Non-potable water is circulated to the laboratories via a constant speed in-line pump located in the penthouse. Each pump motor is 3 hp with a 73.0% nameplate efficiency, and one pump in each set is estimated to run 8,760 hours per year.

PROPOSED CASE This measure proposes to replace the AC motors on each of the two pumps with high efficiency electronically commutated (EC) motors. These direct current motors have higher full-load efficiencies and feature variable speed control. In addition, they maintain a higher efficiency at part load compared with the existing induction motors. As part of this measure, the speed of the motors would be controlled to maintain a loop differential pressure set-point, which would allow for lower flow during periods of low or no load, especially at night and on weekends when the building is primarily unoccupied.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in pump electricity that is used by improving the full and part load efficiency of the motors, as well as from the implementation of variable speed control.

The energy savings associated with this measure were estimated using a time of day spreadsheet model. Estimated weekday and weekend load profiles were developed, assuming that loads would peak in the mid-morning and mid-afternoon when labs may be at greatest occupancy density. Refer to Figure 74 on the following page for the proposed case speed profiles used in the energy model.


Figure 74: Chart showing the proposed case domestic hot water and non-potable water circulation pump speed profiles for typical weekday and weekend operation

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Cir

c P

um

p S

pe

ed

(%

)

Circulator Speed Profiles

Circ Pump VFD Speed Weeked






(978) 208 - 0609


1 3 3 hp EC Motor & Pump Set ea 2 $3,772 $7,544 $150 1 4 $1,200 $8,744

2 3 dP Sensor ea 2 $250 $500 $150 1 4 $1,200 $1,700

3 3 BAS Points & Programming ea 6 $1,500 $9,000 $150 1 2 $1,800 $10,800

4 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $26,644

1 Means







Total $40,544

Opinion of Probable Construction CostECM-03.01 (e)-2: EC Motors on Domestic & Non-Potable Water Circulators


Sources


ECM-03.01 (E)-3 EC MOTORS ON AHU-10, 11 SUPPLY FANS

MEASURE ECONOMICS SUMMARY ECM # 03.01 (e)-3 EC Motors on AHU-10 & 11


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


23,063 $2,306 4,527 $543 27 $270 $3,120 $16,500 5.3

BASE CASE AHU-10 and AHU-11 supply conditioned recirculation air to the elevator machine rooms located in the penthouse. Each AHU features a chilled water coil and 3 hp two-speed supply fan; the fan speed is controlled to maintain a fixed zone cooling set-point of 72°F.

PROPOSED CASE This measure proposes to replace the fan motors on each of the two units with high efficiency electronically commutated (EC) motors. These direct current motors have higher full-load efficiencies and feature variable speed control. In addition, they maintain a higher efficiency at part load compared with the existing induction or permanent split capacitor (PSC) motors.

For each unit, we recommend controlling the speed of the fan to maintain zone temperature set-points using the following sequence:

If the zone temperature is less than or equal to the effective temperature set-point, the supply fan shall be at minimum speed (50%, adjustable) and the chilled water valve shall be closed

Upon a rise in zone temperature above the set-point, the chilled water valve shall open to meet the set-point

If the chilled water valve position is greater than 90% and the zone temperature is still above set-point, the supply fan speed shall increase as necessary to meet the set-point

Upon a drop in zone temperature, the reverse shall occur. The control sequence shall be tuning to prevent hunting of the chilled water valve and supply fan.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan energy that is used by improving the full load and part load efficiency of the supply fan motors. The variable speed capability of the motors also offers greater turndown capability and speed control compared to a two-speed motor.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the AHU-10, 11 system and CAC-1, 2 system and changed the following parameters:

Base Case

AHU-10, 11

FAN-CONTROL: Two Speed

MIN-FLOW-RATIO: 0.5

CAC-1, 2

FAN-CONTROL: Constant Volume

MIN-FLOW-RATIO: 1.0

Proposed Case

AHU-10, 11

FAN-CONTROL: Fan EIR fPLR

MIN-FLOW-RATIO: 0.3

CAC-1, 2

FAN-CONTROL: Fan EIR fPLR

MIN-FLOW-RATIO: 0.5


Figure 75: The trend screenshot below shows the supply fan amperage (BLUE), chilled water valve position (RED), and zone temperature (ORANGE) for AHU-10 serving an elevator machine room. The fan motor amperage trend is consistently between 6.6 - 6.8 amps.






(978) 208 - 0609


1 3 3 hp EC Motor ea 2 $1,800 $3,600 $150 1 4 $1,200 $4,800

2 3 BAS Points & Programming ea 2 $1,500 $3,000 $150 1 2 $600 $3,600

3 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $10,800

1 Means







Total $16,500

Sources

Opinion of Probable Construction Cost ECM-03.01 (e)-3: EC Motors on AHU-10, 11 Supply Fans



ECM-03.01 (E)-4 RETROFIT RO WATER PUMPS WITH VFDS

MEASURE ECONOMICS SUMMARY ECM # 03.01 (e)-4 Retrofit RO Water Pumps with VFDs


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


69,848 $6,985 0 $0 0 $0 $6,985 $42,770 6.1

BASE CASE Filtered and de-ionized water is circulated to the laboratory spaces via a pair of two-stage pumps manufactured by Grundfos. Each pump is rated at 25 hp and has a nameplate efficiency of 88.5%. The pumps supply 350 gpm at 210 feet of head; the relatively high head requirement is the result of the reverse osmosis (RO) filtration that occurs downstream of the pump set. The pumps are controlled in a lead/lag sequence and switch lead positions to maintain equal run hours on the equipment.

PROPOSED CASE This measure proposes to replace the existing TEFC RO filter pump motors with premium efficient units, which would have NEMA nominal efficiencies of 89.5% or greater. In addition, this measure includes installing a VFD on each of the pumps and controlling the speed of the motor to a loop differential pressure set-point. During periods of low filtered water usage, the loop differential pressure would increase and the pump speed would ramp down. Due to the high minimum head requirement of the RO loop, we have assumed a minimum pump speed of no lower than 70% to maintain flow.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in pump energy that is used by improving the full load efficiency of the motors and by reducing their speed during periods of low load on the loop.

The energy savings associated with this measure were estimated using spreadsheet calculation comparing the full load input power of the existing motors at 88.5% efficiency to the proposed motors at 89.5% efficiency. Estimated typical weekday and weekend RO load profiles were developed to model the proposed case pump speeds and corresponding energy consumption. The table below illustrates the weekday and weekend speed profiles used in the proposed case spreadsheet models.


Figure 76: Proposed case weekday and weekend RO pump speed profiles, assuming a minimum pump speed of 70%.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Cir

c P

um

p V

FD S

pe

ed

RO Pump VFD Speed (Proposed Case)

Weekday Weekend






(978) 208 - 0609


1 2 25 hp TEFC Motor ea 2 $2,025 $4,050 $150 1 2 $600 $4,650

2 3 25 hp VFD (18 Pulse) ea 2 $4,860 $9,720 $150 1 4 $1,200 $10,920


4 3 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $25,170

1 Means







Total $42,770

Materials Labor

Sources

Opinion of Probable Construction Cost ECM-03.01 (e)-4: Replace Motors on RO Water Pumps

General


ECM-04.02 (E) COMPARATIVE ENTHALPY ECONOMIZER ON AHU-9

MEASURE ECONOMICS SUMMARY ECM # 04.02 (e) Comparative Enthalpy Economizer on AHU-9


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


425 $43 2,449 $294 0 $0 $337 $10,650 31.6

BASE CASE AHU-9 is a mixed air unit with a design supply airflow of 60,000 cfm and serves office and administration areas along the eastern perimeter of the building. The unit features a comparative economizer that is based on the difference between outdoor and return air dry bulb temperature. When the outdoor air temperature is less than the return air temperature, the economizer is enabled regardless of humidity conditions. Refer to Figure 77 on Page 285 for a trend screenshot illustrating this sequence.

PROPOSED CASE This measure proposes to implement a comparative enthalpy economizer on AHU-9 so that the sequence is enabled when the outdoor air enthalpy is less than the return air enthalpy. This measure will include the installation of a new return air relative humidity sensor in order to calculate return air enthalpy. The building’s existing weather station will be used to calculate outdoor air enthalpy.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in mechanical cooling energy that is used when the outdoor air temperature is less than the return air temperature, but the total heat content of the air (enthalpy) is greater. Similarly, savings are realized when the outdoor air temperature is greater than the return, but the enthalpy of the outdoor air is lower.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-9 and changed the following parameters:

Base Case

OA-CONTROL: Dual Temperature

DUAL-TEMP-DP: 0°F

Proposed Case



DUAL-ENTHLAPY-DH: 0 Btu/lb


Figure 77: The trend screenshot below illustrates the comparative economizer sequence on AHU-9. When the outdoor air temperature (BLUE) is greater than the return air temperature (ORANGE), the outdoor air damper position (RED) goes from fully open (14 psig) to minimum position (6 psig). The period highlighted by the vertical rule (black line) indicates this switch over from economizer to minimum outdoor air.






(978) 208 - 0609


1 3 Return Humidity Sensor ea 1 $350 $350 $150 1 4 $600 $950


3 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $5,750

1 Means







Total $10,650

Sources

Opinion of Probable Construction CostECM-04.02 (e): Comparative Enthalpy Economzier on AHU-9



ECM-04.09 (E)-1: SCHEDULING AND SET-POINTS ON AHU-9 ZONES

MEASURE ECONOMICS SUMMARY ECM # 04.09 (e)-1 Scheduling and Set-points on AHU-9 Zones


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


13,052 $1,305 6,278 $753 325 $3,247 $5,306 $39,650 7.5

BASE CASE AHU-9 serves office and administration areas on Levels 2 - 9 along the eastern perimeter of the building. The existing schedule for AHU-9 is Monday - Saturday 5:45am - 7:00pm, although the historical trends from June and September 2014 show the unit ran several Sundays. Maintenance personnel have indicated that during the summer, the AHU is sometimes scheduled to run at night and on weekends during the summer due to previous issues with loss of space temperature control and excessive recovery times. During the winter, perimeter radiant panels are used to maintain unoccupied heating set-points while AHU-9 is off and as a result, recovery has not been an issue. See Figure 78 on Page 289 for a trend chart showing AHU-9’s operation during June 2014.

The majority of office and support zones served by AHU-9 were observed to be occupied between 6:30am - 7:30pm Monday - Friday with an occupied zone temperature set-point of 72°F. During unoccupied periods in the summer, a 2°F temperature setback was observed. However, since AHU-9 was off for a significant number of hours during the unoccupied period, zone temperatures often rose higher than unoccupied cooling set-points during the summer months. For example, the typical unoccupied cooling set-point is 74°F but zone temperatures were observed to reach up to 82°F over weekend periods.

Some office zones were found to have fixed temperature set-points so that whenever AHU-9 was running, the terminal box would control to the occupied set-point regardless of actual occupancy.

PROPOSED CASE This measure proposes to implement global occupied and unoccupied heating and cooling zone temperature set-points in the Building Automation System. Based on walkthroughs of the office areas, thermostats do not appear to have local adjustment capabilities, so no limitation on user adjustment is necessary. We recommend implementing occupied set-points of 71°F heating and 73°F cooling (2°F dead-band), and unoccupied set-points of 62°F heating and 80°F cooling. Implementing separate occupied heating and cooling set-points with a 2°F dead-band may reduce energy consumption by allowing zones to ‘drift’ between the set-points before reheat is needed or additional cooling airflow is supplied.


We also recommend reprogramming the equipment schedule for AHU-9 so that the unit runs on weekends only when necessary to maintain unoccupied setbacks. During the unoccupied period, if three (adjustable) or more zones are not meeting their set-points, we recommend cycling AHU-9 on until those zone set-points are met.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan, heating, and mechanical cooling energy that is used by tightening equipment schedules to match the occupancy of the building’s office areas and implementing more effective space temperature set-points.


Base Case

FAN-SCHEDULE: AHU-9 Fan Sch

COOL-TEMP-SCH: S1 Sys1 (PMZS) Cool Sch

HEAT-TEMP-SCH: S1 Sys1 (PMZS) Heat Sch

NIGHT-CYCLE: No

Proposed Case

FAN-SCHEDULE: ECM-04.09-1 AHU-9 Fan Sch

COOL-TEMP-SCH: ECM-04.09-1 AHU-9 Cool Sch

HEAT-TEMP-SCH: ECM-04.09-1 AHU-9 Heat Sch

NIGHT-CYCLE: Cycle on Any


Figure 78: The trend screenshot below shows the operation of AHU-9 during the month of June 2014. The supply airflow trend shows that the AHU typically operates six days per week, but ran constantly between 6/21 - 6/25, possibly as a result of very warm outdoor air temperatures.






(978) 208 - 0609


1 3 Programming ea 105 $0 $150 1 1 $15,750 $15,750

3 4 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $21,750

1 Means







Total $39,650

Sources

Opinion of Probable Construction CostECM-04.09 (e)-1: Scheduling and Set-points on AHU-9 Zones



ECM-04.09 (E)-2 REPROGRAM AHU-7 PREHEAT CONTROL SEQUENCE

MEASURE ECONOMICS SUMMARY ECM # 04.09 (e)-2 Reprogram AHU-7 Preheat Control Sequence


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


23,886 $2,389 269,211 $32,305 2,828 $28,282 $62,976 $10,000 0.2

BASE CASE AHU-7 is one of two make-up air units that serve the vivarium on the first floor. Historical trend data shows that the preheat valve on AHU-7 is maintaining a minimum preheat discharge air temperature of 57°F at all times. This is contributing to simultaneous heating and cooling since the chilled water coil must constantly supply air at approximately 47°F to meet the 50°F minimum discharge air temperature set-point. Figure 79 on Page 293 shows a trend screenshot that illustrates this sequence of operation on AHU-7.

PROPOSED CASE This measure proposes to reconfigure the preheat temperature control sequence for AHU-7 so that it performs as described in the as-built sequence of operation:

In heating operation, the cooling coil valve is closed. In this mode, the [preheat] valves and face and bypass damper modulate to maintain the preheat discharge temperature at the preheat discharge temperature set-point. The preheat discharge set-point is reset between 5 degrees below set-point to the discharge air set-point as necessary to maintain the unit discharge temperature at the discharge temperature set-point.

The preheat discharge air temperature set-point should properly reset to maintain the unit discharge air temperature set-point without the need for mechanical cooling.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in steam preheat and chilled water energy that is used when outdoor air is preheated to a temperature higher than necessary and then subsequently cooled to meet the discharge air set-point.



Base Case

PREHEAT-SOURCE: Steam Loop

PREHEAT-T: 57°F

Proposed Case

PREHEAT-SOURCE: Not Installed

PREHEAT-T: n/a

HEAT-SOURCE: Steam Loop


Figure 79: The trend screenshot below shows that the preheat discharge air temperature (blue) is maintained at a minimum temperature of approximately 57-58°F. During periods highlighted in gray, the preheat valve (orange) opens to maintain this minimum set-point. The chilled water valve then opens meet the discharge air temperature set-point (Light Blue) of 50°F.






(978) 208 - 0609


1 3 Programming ea 1 $0 $150 1 16 $2,400 $2,400

2 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $5,400

1 Means







Total $10,000

ECM-04.09 (e)-2: Reprogram AHU-7 Preheat Control Sequence


Sources



ECM-04.09 (E)-3 REDUCE AIR CHANGE RATES IN LABS

MEASURE ECONOMICS SUMMARY ECM # 04.09 (e)-3 Reduce Air Change Rates in Labs


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


12,778 $1,278 129,252 $15,510 6,732 $67,321 $84,109 $682,450 8.1

BASE CASE The average minimum air change rate in the building’s laboratories is currently 9.9 ACH, which includes alcoves and fume hoods. Since the hoods are constant volume and require a high amount of exhaust relative to the floor space the alcoves occupy, the air change rates in these areas are higher than the rest of the laboratories. Excluding alcoves, the average air change rate in the labs is approximately 4.6 ACH. Based on a review of testing, adjusting, and balancing reports available from the most recent airflow reduction, the limiting factor for many of the VAV boxes is the minimum airflow recommended by the box’s manufacturer. The as-built mechanical schedules indicate most boxes have a 4:1 turndown, which is confirmed by recent testing, adjusting, and balancing records. Below a certain threshold, accurate flow control is not guaranteed and as a result, boxes were balanced so that their minimums were no lower than the manufacturer’s recommendation.

According to the 2011 Edition of ASHRAE HVAC Applications, Chapter 14, “Reducing ventilation requirements in laboratories and vivariums based on real time sensing of contaminants in the room environment offers opportunities for energy conservation. This approach can potentially reduce lab air change rates down safely to as low as 2 air changes per hour when the lab air is “clean” and the fume hood exhaust or room cooling load requirements do not require higher airflow rates. Previous lab environment studies have shown that lab rooms are on average “clean” of contaminants in excess of about 98% of the time.”

PROPOSED CASE A review of the facility’s existing Aircuity real-time contaminant monitoring system suggests that a lower air change rate in line with ASHRAE’s guidance may be possible during unoccupied periods. This measure proposes to consider reducing the average air change rate in labs on levels 2 - 9 (excluding alcoves) to 2.5 ACH between 10:00pm - 6:00am Monday - Sunday. This unoccupied flow reduction would be accomplished by retrofitting the existing VAV and VEV boxes with new differential pressure transducers that are used to calculate airflow, which would allow for greater turndown while maintaining control stability and flow measurement accuracy.


The proposed sequence would maintain the existing temperature and contaminant (TVOC, CO2, and particulates) control sequences so that if the zone cooling set-point is not met or a contaminant concentration above the allowable threshold is detected, supply and exhaust airflows would automatically be increased as necessary according to the existing sequences.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan, heating, and cooling energy that is used as a result of lower make-up and exhaust airflow during unoccupied periods.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on all Level 2 - 8 bay lab zones and changed the following parameters:

Base Case

MIN-FLOW-SCH: undefined

MIN-FLOW/AREA: 0.7 (Bay Labs), 0.65 (Alcoves/Corridors)

Proposed Case

MIN-FLOW-SCH (Bay Labs): ECM-04.09-3 Min Flow Sch

o Monday - Sunday 6:00am - 10:00pm: 0.70

o All other hours: 0.38 (54.3% of existing, 2.5/4.6 ACH)

MIN-FLOW/AREA: 0.65 (Alcoves/Corridors)






(978) 208 - 0609


1 3 dP Transducer Replacement ea 404 $100 $40,400 $150 1 2 $121,200 $161,600

2 3 Programming ea 404 $0 $150 1 1.25 $75,750 $75,750

3 3 TAB ea 404 $0 $150 2 1 $121,200 $121,200

4 4 As-built ea 1 $0 $150 1 40 $6,000 $6,000


Subtotal $378,950

1 Means







Total $682,450

Opinion of Probable Construction CostECM-04.09 (e)-3: Reduce Air Change Rates in Labs


Sources


ECM-04.09 (E)-4 HOT WATER LOOP DIFFERENTIAL PRESSURE RESET

MEASURE ECONOMICS SUMMARY ECM # 04.09 (e)-4 Hot Water Loop Differential Pressure Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


940 $94 0 $0 34 $337 $431 $10,000 23.2

BASE CASE Three hot water loops are used to supply heat to different terminal devices throughout the building. One loop (HE-3/4) supplies hot water to the office and lab reheats, one (HE-5/6) serves reheats in the vivarium, and the third loop (HE-1/2) serves perimeter radiant panels and baseboard in the labs and offices. All three loops were observed to operate at a fixed differential pressure set-point. HE-1/2 operates at 12.00 psig while HE-3/4 and HE-5/6 both operate at 10.00 psig.

PROPOSED CASE This measure proposes to implement a load driven differential pressure reset on the loop served by HE-1/2 based on average radiant panel hot water valve position. Every 15 minutes, the Siemens BAS will poll the radiant panel valve positions and perform a ‘high select’ of the five most open valves. If the average of the five most open valve positions is between 80-90%, the loop differential set-point will be maintained at its current level. If the average of the top five is below 80%, the differential set-point will be cascaded lower to a possible minimum of 6 psig. If the average of the five most open valve positions is greater than 90%, the set-point will be cascaded higher up to a maximum of 12 psig.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the “Radiation HW Loop” system which models HE-1/2 and the associated pumps (HWP-1, 2). The following parameters were changed as part of the parametric run.

Base Case


Proposed Case






(978) 208 - 0609


1 3 Programming ea 1 $0 $150 1 24 $3,600 $3,600

2 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $6,600

1 Means







Total $10,000


Opinion of Probable Construction CostECM-04.09 (e)-4: Hot Water Loop Differential Pressure Reset

Sources


ECM-04.09 (E)-5 PROCESS CHW LOOP DIFFERENTIAL PRESSURE RESET

MEASURE ECONOMICS SUMMARY ECM # 04.09 (e)-5 Process CHW Loop Differential Pressure Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


7,874 $787 0 $0 0 $0 $787 $20,500 26.0

BASE CASE The building’s process chilled water loop is used as a condenser water loop for the environmental room DX compressors. The loop pumps (SCHP-3, SCHP-4) are equipped with variable frequency drives (VFD) and modulate to maintain a fixed differential pressure set-point of 12 psig. A typical weekday and weekend daily load profile for the loop was developed using approximately four weeks of historical trend data points including supply and return temperature, pump status, and pump VFD speed. The data indicated that the daily load profile was consistent and was not directly impacted by outdoor air conditions, since environmental rooms are generally located in the core of the building and are well-insulated.

Figure 80: The chart below shows the typical weekend and weekend load profiles for the building’s process chilled water loop. These profiles were developed using loop design data and approximately four weeks of historical trend data for supply and return loop temperatures, as well as pump VFD speed.

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

12:00 AM 4:00 AM 8:00 AM 12:00 PM 4:00 PM 8:00 PM 12:00 AM

Pro

cess

CH

W L

oad

(M

MB

tu/h

r)

Hour of Day

Process CHW Load Profile

Weekday Weekend


PROPOSED CASE We proposed adding a flow meter to the process chilled water loop and cascading the differential pressure set-point based on loop flow. The loop set-point would be set to a maximum of 12 psig at 90% of design flow (333 gpm) and would be set to a minimum of 6 psig at 60% of design flow (222 gpm). This will allow the control system to maintain the necessary pressure at varying loads.


The energy savings associated with this measure were estimated using spreadsheet models for the typical weekday and weekend process loop loads. In the existing case, total pump head was calculated using the following affinity law equation, based on the observed average pump speed at each hour of the day.

𝐻2

𝐻1= (

𝑁2

𝑁1)

2

Where H2 is the calculated head, H1 is the pump design head, and the ratio of N2/H1 represents the hourly observed pump speed. Existing case pump input power was calculated using the following equation.

𝐼𝑛𝑝𝑢𝑡 𝑃𝑜𝑤𝑒𝑟 (𝑘𝑊) =

(𝑄 ∗ 𝐻)(3960 ∗ 𝜂, 𝑝𝑢𝑚𝑝)

𝜂, 𝑚𝑜𝑡𝑜𝑟∗ 0.746 [

𝑘𝑊

𝑏ℎ𝑝]

Where Q is the hourly average loop flow calculated based on pump speed and the design flow of the loop, H is the calculated pump head, η, pump is the estimated mechanical efficiency on the pump, and η, motor is the is the estimated electrical efficiency on the motor.

In the proposed case, a loop differential pressure set-point reset profile was specified based on the existing case loop flow. The new hourly pump head was calculated as the difference between the existing case head and the reduction in the loop differential pressure set-point. The proposed case pump motor input power was calculated using the same equation above, substituting the new pump head profile.


Figure 81: The trend screenshot below shows the differential pressure (RED) for the building’s process chilled water loop, and chilled water pump VFD signal (BLUE/ORANGE) in Hz. The chart shows that the dP set-point remained fixed throughout the month of July.






(978) 208 - 0609


1 3 CHW Flow Meter ea 1 $4,000 $4,000 $150 1 12 $1,800 $5,800


3 4 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $11,200

1 Means







Total $20,500

Sources

Opinion of Probable Construction CostECM-04.09 (e)-5: Process CHW Loop Differential Pressure Reset



ECM-04.11 (E)-1 HEAT RECOVERY ON MAKE-UP AIR UNITS (AHU 1-6)

MEASURE ECONOMICS SUMMARY ECM # 04.11 (e)-1 Heat Recovery on Make-up Air Units (AHU 1-6)


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-300,403 -$30,040 9,269 $1,112 20,367 $203,671 $174,743 $995,504 5.7

BASE CASE The six VAV make-up air units serving the building lab areas (AHU-1 through AHU-6) each have a corresponding set of three exhaust fans which are used to remove contaminants and maintain adequate lab pressurization. The table below summarizes the nameplate design parameters for each of the AHUs.

Unit No.

Service

Design Supply Fan Data

Total Supply Airflow

Motor Namplate

Measured bhp

Total Static

External Static

Fan Type

cfm hp bhp " WC " WC

AHU-1 Labs FL-2,3,4,5 70,000 75 (2) x 57.3 7.50 3.00 Vane Axial






Each AHU’s corresponding set of three Strobic exhaust fans are staged based on measured exhaust airflow, and each is equipped with a VFD that modulates to maintain a duct static pressure set-point. For example, one exhaust fan operates if the measured airflow is less than 22,000 cfm. If the airflow is between 22,000 - 45,000 cfm, a second exhaust fan stages on. The third exhaust fan stages on if the measured airflow exceeds 45,000 cfm. Common plenums measuring 84” W x 76” H x 20’ 4” L connect each set of three exhaust fans directly below the roof surface.

The make-up and exhaust systems are completely separated due to the contaminated nature of the exhaust and there is no form of heat recovery currently installed to precondition outdoor air.


PROPOSED CASE This measure proposes a new run-around heat recovery loop on each of the make-up air units located in the penthouse serving labs on Floors 2 - 9. The two make-up units serving the vivarium are not included in this measure due to the location of the units on the first floor.

This measure would include installing a new coil in each of the six exhaust ducts located in the penthouse corresponding to AHU 1-6. Due to the relatively high velocities in the exhaust ducts, the heat recovery coils would be located in the plenums directly below the roof-mounted Strobic fans, since these have significantly larger cross sectional areas. For example, the horizontal cross sectional area of each exhaust plenum is approximately 140 ft2, which would result in an average coil face velocity of 500 fpm at design capacity (70,500 cfm). The coils would be constructed of either stainless steel or coated aluminum to handle the potentially corrosive exhaust leaving the laboratory fume hoods.

A new coil would also be installed between the outdoor air intake and steam preheat of each MAU, which may require relocation of the pre-filter section. A 20% glycol water loop would connect the two coils and a new control sequence added to take advantage of exhaust heat recovery when the outdoor air temperature is below the MAU’s discharge air temperature set-point, or when the outdoor air temperature is greater than the exhaust air temperature. The loop would remain off when the outdoor air temperature is between the discharge air temperature set-point and the exhaust air temperature to prevent unwanted heat transfer.

The proposed sequence of operation for the run-around heat recovery loop would be as follows:

When the outdoor air temperature is less than preheat discharge air temperature set-point by more than 4°F (adjustable), the run-around loop would operate to preheat the outdoor air up to the set-point. If the discharge air temperature set-point is not met using the heat recovery coil alone, the preheat coil valve shall modulate as necessary to maintain the effective preheat discharge set-point.

When the outdoor air temperature is between the preheat discharge air temperature set-point and the exhaust air temperature, the heat recovery loop shall be off, the preheat valve closed, and the chilled water valve shall modulate to maintain the discharge air temperature set-point.

When the outdoor air temperature is greater than the exhaust air temperature by more than 4°F (adjustable), the run-around loop would operate to precool the outdoor air as much as possible. The chilled water valve would modulate to maintain the effective discharge air temperature set-point.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in steam preheat and chilled water cooling energy that is used by recovering energy from each MAU’s exhaust airstream.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on six total systems including AHU-1 through AHU-6 and changed the following parameters:

Base Case

RECOVER-EXHAUST: No

ERV-RECOVER-TYPE: n/a

ERV-HX-CONFIG: n/a

ERV-SENSIBLE-EFF: n/a

ERV-RUN-CTRL: n/a

OA-EXHAUST-DT: n/a

ERV-RECOVER-MODE: n/a

ERV-TEMP-CTRL: n/a

ERV-CAP-CTRL: n/a

ERV-FANS: n/a

ERV-FAN-EFF: n/a

ERV-MOTOR-CLASS: n/a

ERV-HX-KW: n/a

Proposed Case

RECOVER-EXHAUST: Yes

ERV-RECOVER-TYPE: Sensible HX

ERV-HX-CONFIG: Counter Flow

ERV-SENSIBLE-EFF: 0.45

ERV-RUN-CTRL: OA Exhaust DT

OA-EXHAUST-DT: 4°F

ERV-RECOVER-MODE: OA Heat/Cool

ERV-TEMP-CTRL: Mixed Air Reset

ERV-CAP-CTRL: Modulate HX

ERV-FANS: HVAC-Supply/Return

ERV-FAN-EFF: Default (Assumes existing supply fan efficiency)

ERV-MOTOR-CLASS: Default (Assumes existing supply fan motor class)


ERV-HX-KW: 6 kW (for each 3-AHU eQuest System)


Figure 82: The Siemens building automation system screenshot below shows one of the eight typical laboratory and vivarium exhaust systems, each with three variable volume fans. The red box inserted in the screenshot represents the approximate location of the proposed exhaust heat recovery coil.


Figure 83: The photo below shows the proposed location for an exhaust heat recovery coil on one of the eight systems, just before the manifold that connects the three exhaust fans. This plenum offers a relatively large cross sectional area that would result in a design coil face velocity of 500 fpm.


COST ESTIMATE The estimate on the following page was developed using estimates for materials, labor, and programming costs. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable.





(978) 208 - 0609


1 3 Exhaust Coil ea 6 $13,735 $82,412 $150 4 8 $28,800 $111,212

2 3 MAU Coil ea 6 $7,849 $47,093 $150 4 8 $28,800 $75,893

3 4 3 hp Pump / Motor Set ea 12 $3,000 $36,000 $150 2 12 $43,200 $79,200

4 3 Piping & Fittings lf 600 $28 $16,500 $150 2 0.2 $36,000 $52,500

5 3 Valves ea 12 $1,775 $21,300 $150 1 6 $10,800 $32,100

6 3 Electrical ea 6 $0 $0 $150 2 16 $28,800 $28,800

7 4 Rigging ea 12 $1,200 $14,400 $150 $0 $14,400

8 3 Sheet Metal / Structural Work ea 12 $3,000 $36,000 $150 2 24 $86,400 $122,400

9 3 BAS Points ea 30 $1,500 $45,000 $150 $0 $45,000

10 3 Programming ea 6 $0 $0 $150 1 16 $14,400 $14,400

11 3 TAB ea 6 $0 $150 2 12 $21,600 $21,600

12 4 As-built ea 1 $0 $150 1 40 $6,000 $6,000


Subtotal $614,304

1 Means







Total $995,504

Sources

Opinion of Probable Construction CostECM-04.11 (e)-1: Heat Recovery on Make-up Air Units (AHU 1-6)



ECM-04.11 (E)-2 INSTALL PASSIVE CHILLED BEAMS IN LABS

MEASURE ECONOMICS SUMMARY ECM # 04.11 (e)-2 Install Passive Chilled Beams in Labs


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


405,347 $40,535 233,302 $27,996 2,120 $21,203 $89,734 $1,862,993 20.8

BASE CASE Historical trend reviews and facility walkthroughs have shown that the laboratories have significant internal loads, causing supply airflow to increase above the minimum 4.6 ACH recently set as part of an airflow reduction. For example, many VAV boxes were observed to be at airflow levels double the design minimum on a typical weekday in order to maintain zone temperature set-points. See Figure 84 for examples of this pattern.

The cooling loads in the labs are suspected to be driven primarily by equipment including freezers, centrifuges, bio-safety cabinets, etc, but also by lighting, occupants, solar gain, and shell conduction.

PROPOSED CASE This measure proposes installing passive chilled beams in each of the laboratories in order to reduce the amount of make-up air flow needed during occupied periods to meet zone cooling set-points. A chilled beam is mounted in or suspended from the ceiling that works using the principles of convective and radiant cooling. Chilled water is passed through a coil in the beam (heat exchanger) and as the beam chills the air around it, the air becomes denser and falls to the floor. It is replaced by warmer air moving up from below, causing a constant flow of convection and cooling the room.

We recommend sizing the chilled beam system for the cooling load above the capacity supplied by the make-up air units at the existing minimum air change rate (approximately 4.6 ACH for the bay labs, excluding alcoves). Based on the observed minimum make-up unit total supply airflow of 146,000 cfm, and a combined capacity of 420,000 cfm, the chilled beam system would be sized at approximately 400 tons. This calculation assumes an average zone temperature of 72°F and minimum entering primary air temperature of 56°F.

The chilled beams would be used to supplement the cooling supplied by the make-up air units at minimum flows. We recommend configuring the sequence of operation so that the existing laboratory terminal boxes maintain minimum supply and exhaust airflow set-points. Upon a call for additional cooling in any zone, the corresponding chilled beam’s control valve would open to meet the zone set-point. If the beam’s valve opens fully and the zone set-point is still not met, the make-up airflow set-point would be increased. Upon a drop in zone temperature, the


reverse sequence would occur. If at any time the Aircuity demand-controlled ventilation signal rises above minimum, the make-up airflow rate would be increased according to the existing sequence of operation and any corresponding chilled beam control valves closed.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan, steam preheat, and chilled water cooling energy that is used by transferring cooling load from the make-up units to passive chilled beams.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on six total systems including AHU-1 through AHU-6 and changed the following parameters:

Base Case

TYPE-SYSTEM: Variable Air Volume

RETURN-AIR-PATH: Duct

SUPPLY-KW/FLOW: 0.001320

RETURN-KW/FLOW: 0.001298

SUPPLY-FLOW: 210,000

INDUCTION-RATIO: n/a

Proposed Case

TYPE-SYSTEM: Induction Unit

RETURN-AIR-PATH: Duct

SUPPLY-KW/FLOW: 0.001300 (AHU-1,4,5); 0.001100 (AHU-2,3,6)

RETURN-KW/FLOW: 0.001100 (AHU-1,4,5); 0.00090 (AHU-2,3,6)

SUPPLY-FLOW: 65,000 (AHU-1,4,5); 81,000 (AHU-2,3,6)

INDUCTION-RATIO: 1.80


Figure 84: The trend screenshot below shows supply airflow (RED), zone temperature (BLUE), zone temperature set-point (ORANGE), and the VAV box reheat valve position (PINK) over a two week period in September for VAV-260R4, served by AHU-1. This airflow profile is typical of many VAV boxes, where the airflow increases above minimum during the occupied period on weekdays (see periods highlighted in gray). Since supply airflow does not increase significantly during the daylight hours on weekends, solar gain is not suspected to be the driving cause of the cooling load and corresponding airflow demand.


COST ESTIMATE The estimate on the following page was developed using estimates for materials, labor, and programming costs. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable.





(978) 208 - 0609


1 3 Chilled Beam ea 56 $1,500 $84,000 $150 2 8 $134,400 $218,400

2 3 Ceiling Work ea 56 $250 $14,000 $150 1 0.5 $4,200 $18,200

2 1 2" Sch 40 Piping, Valves, Fittings lf 7848 $9.80 $76,910 $150 1 0.25 $294,300 $371,210

3 1 4" Sch 40 Piping, Valves, Fittings lf 324 $49 $15,876 $150 1 0.45 $21,870 $37,746

4 1 2" Insulation ea 7848 $3 $26,762 $150 1 0.094 $110,657 $137,418

5 1 4" Insulation ea 324 $5 $1,568 $150 1 0.107 $5,200 $6,768

6 1 Plate & Frame HX ea 1 $53,500 $53,500 $150 2 52 $15,600 $69,100

7 1 Pump / Motor ea 2 $9,625 $19,250 $150 1 15 $4,500 $23,750


9 3 TAB ea 56 $0 $150 2 2 $33,600 $33,600

10 4 As-built ea 1 $0 $150 1 40 $6,000 $6,000


Subtotal $1,034,993

1 Means







Total $1,862,993


Sources

Opinion of Probable Construction CostECM-04.11 (e)-2: Install Passive Chilled Beams in Labs


ECM-18.00 (E)-1 STATIC PRESSURE RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-1 Static Pressure Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


321,723 $32,172 89,563 $10,748 -320 -$3,202 $39,718 $54,000 1.4

BASE CASE AHU-1, 2, 3, 4, 5, and 6 are variable volume make-up air units that serve laboratories and corridors on Levels 2 - 8. AHU-9 is a variable volume mixed-air unit that serves office and administration areas on Levels 1 - 8. Each of these units features a fixed duct static pressure set-point, as shown in the table below.

AHU Tag Static Pressure

Set-point

AHU-# " WC

AHU-1 1.5

AHU-2 1.5

AHU-3 1.1

AHU-4 1.2

AHU-5 0.8

AHU-6 1.5

AHU-9 1.5

Historical trends show that terminal device airflow is considerably lower during unoccupied periods when laboratory plug loads are reduced, indicating an opportunity to reset duct static pressure during periods of low load.

PROPOSED CASE This measure proposes to reset the duct static pressure set-point on AHU-1, 2, 3, 4, 6, and 9 using a new cascading control algorithm. AHU-5 is not included in this measure since the duct static pressure set-point is already at a relatively low level. Every 15 minutes the BAS will perform a damper position “high select” on all VAV boxes served by each AHU. If the average of the top three (user selectable from 1 to 10) “high select” boxes is between 85% and 90% open the system shall hold its current duct static pressure set-point. If the average is below 80% open the BAS logic shall cascade its set-point down to a low of 0.8” WC. If the average of the top five boxes is greater than 90% then the system duct static pressure set-point shall cascade up to a


maximum of 1.5” WC for AHU-1, 2, 6, and 9, 1.1” WC for AHU-3, and 1.2” WC for AHU-4 . The cascading reset loop shall be tuned to avoid unnecessary hunting.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-1, 2, 3, 4, 6, and 9, and changed the supply fan “EIR f(PLR)” performance curve that calculates fan input power as a function of airflow part load ratio. The curve used in the base case is the standard curve available from the eQuest library.

A custom curve was developed for the proposed case to model a demand-based duct static pressure reset. At minimum a fan part load ratio of 30%, the proposed fan energy input ratio (EIR) was 0.297 compared to an existing EIR of 0.372, resulting in 20% savings at lowest part load. EIR is defined to be the ratio of electric energy input (Btu/hr) to the rated energy output (Btu/hr) of the fan. The chart below illustrates the existing and proposed can fan curves used to estimate energy savings.


0

0.2

0.4

0.6

0.8

1

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Ele

ctri

c In

pu

t R

atio

Part Load Ratio

AHU-1, 2, 3, 4, 6, 9 Static Pressure Reset Curve

Existing Case Curve (No SP Reset) Proposed Case Curve (SP Reset)


Figure 86: The trend screenshot below shows the duct static pressure set-points for AHU-1, 2, 3, 4, 6, and 9 between 9/15/2014 - 10/14/2014. All static pressure set-points remain fixed during this period.






(978) 208 - 0609


1 3 Programming ea 7 $0 $150 1 24 $25,200 $25,200

2 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $30,000

1 Means







Total $54,000

Opinion of Probable Construction CostECM-18.00 (e)-1: Static Pressure Reset


Sources


ECM-18.00 (E)-2 DISCHARGE AIR TEMPERATURE RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-2 Discharge Air Temperature Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-2,510 -$251 462,855 $55,543 -693 -$6,926 $48,365 $17,200 0.4

BASE CASE Historical trends show that AHU-3 and AHU-4 have a discharge air temperature reset that is based on outdoor air temperature. Figure 87 on Page 324 illustrates the reset observed on these units. AHU-1, 2, 5, and 6 were observed to have a fixed discharge set-point of 55°F throughout the spring, summer, and fall seasons.

PROPOSED CASE This measure proposes to implement a load-based discharge air temperature reset on AHU-1 through AHU-6 in tandem with the static pressure reset proposed in ECM-18.00-1. Every 15 minutes the BAS will poll the zone temperature error (zone temperature above/below set-point) on all VAV boxes served by each AHU. If the system duct static pressure set-point is at minimum and the average of the top five zone temperature error values are between 0.5°F - 1.0°F (zone temperature 0.5 - 1.0°F above cooling set-point), the system shall hold its current discharge air temperature set-point. If the average of the top five error values is below 0.5oF, the BAS logic shall cascade the discharge air temperature higher, up to maximum of 60°F. If the average of the top five zone error values is greater than 1.0°F then the system discharge temperature set-point shall cascade down to a minimum of 55°F. The cascading reset loop shall be tuned to avoid unnecessary hunting.

This control sequence may be active primarily during the unoccupied period when internal loads are lowest and is intended to be implemented with a static pressure reset. The recommendations have been made to minimize negative interaction between the two reset strategies.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in cooling energy that is used when a higher supply air temperature can be used to maintain zone temperature set-points. Savings are achieved only when the outdoor air temperature is greater than ~52°F, since the make-up air units will be in a heating mode below this point with a minimum discharge set-point of 55°F.


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-1, 2, 3, 4, 5, and 6, and changed the following parameters:

Base Case

Cool Control: n/a

Reset Priority: n/a



Proposed Case


Reset Priority: Airflow first




Figure 87: The chart below summarizes the discharge air temperature set-point reset observed on AHU-3 and AHU-4. The red line represents actual data points collected between 9/15/2014 - 10/14/2014 and the black trend line is a linear extrapolation of the dataset to the estimated maximum discharge set-point of 60°F.

54

55

56

57

58

59

60

61

62

0 10 20 30 40 50 60

Dis

char

ge A

ir T

em

pe

ratu

re S

et-

po

int

(°F)

Outdoor Air Temperature (°F)

AHU-3, 4 Discharge Air Reset

Discharge Air Set-point






(978) 208 - 0609


1 3 Programming ea 6 $0 $150 1 8 $7,200 $7,200

2 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $11,400

1 Means







Total $17,200

Sources

Opinion of Probable Construction CostECM-18.00 (e)-2: Discharge Air Temperature Reset



ECM-18.00 (E)-3 REPLACE LEAKING PREHEAT VALVES

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-3 Replace Leaking Preheat Valves


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 168,570 $20,228 2,141 $21,406 $41,634 $19,050 0.5

BASE CASE AHU-7 and 8 are make-up air units that serve the vivarium and surrounding 1st floor support spaces. Historical trend data suggests that the steam preheat valves on these AHUs may be leaking by, with an average observed temperature rise of approximately 4-5°F. Figure 88 on Page 328 illustrates this potential issue on AHU-7.

PROPOSED CASE This measure proposes to replace the preheat valves on AHU-7 and AHU-8 to eliminate leak-by.

ENERGY SAVINGS METHODOLOGY The savings associated with this measure were calculated using a customized weather bin spreadsheet model. The magnitude of the leak-by was calculated for each 5°F outdoor temperature bin and the resulting excess heating load was calculated using the formula below:


Where,









∆𝑇𝑆𝐹 = 2545 ∗ 𝑃 ∗ [(1 − 𝐸𝐹) + (

1𝐸𝑀

− 1)]

1.08𝑄


Figure 88: The trend screenshot below shows that AHU-7’s preheat discharge air temperature (DARK BLUE) is consistently greater than the outdoor air temperature (RED) while the preheat valve pneumatic signal (LIGHT BLUE) is 14 psig (fully closed). This suggests the preheat valve is either incorrectly positioned or leaking by.






(978) 208 - 0609


1 1 6" Control Valve ea 2 $2,675 $5,350 $150 2 4 $2,400 $7,750


3 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $10,450

1 Means







Total $19,050

Opinion of Probable Construction CostECM-18.00 (e)-3: Replace Leaking Preheat Valves


Sources


ECM-18.00 (E)-4 REPLACE LEAKING CHILLED WATER VALVE

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-4 Replace Leaking Chilled Water Valve


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 41,958 $5,035 533 $5,328 $10,363 $10,425 1.0

BASE CASE AHU-9 is a variable volume mixed air unit serving the office and administration areas on Levels 1 - 8. Historical trend data suggests that the chilled water valve on this unit may be leaking by, with an average observed temperature drop of 3.5°F observed across the coil. Figure 89 on Page 332 illustrates this potential issue.

PROPOSED CASE This measure proposes to replace the chilled water valve on AHU-9 to eliminate leak-by.

ENERGY SAVINGS METHODOLOGY The savings associated with this measure were calculated using a customized weather bin spreadsheet model. The magnitude of the leak-by was calculated for each 5°F outdoor temperature bin and the resulting excess heating load was calculated using the formula below:


Where,









∆𝑇𝑆𝐹 = 2545 ∗ 𝑃 ∗ [(1 − 𝐸𝐹) + (

1𝐸𝑀

− 1)]

1.08𝑄


Figure 89: The trend screenshot below shows that AHU-9’s cooling coil discharge air temperature (PINK) is less than the preheat discharge air (RED) and mixed air temperature (DARK BLUE) when the chilled water valve pneumatic signal (LIGHT BLUE) is 0 psig (closed).






(978) 208 - 0609


1 1 6" Control Valve ea 1 $2,675 $2,675 $150 2 4 $1,200 $3,875


3 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $5,525

1 Means







Total $10,425

Sources

Opinion of Probable Construction CostECM-18.00 (e)-4: Replace Leaking Chilled Water Valve



ECM-18.00 (E)-5 REDUCE AHU-9 MINIMUM OUTDOOR AIR

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-5 Reduce AHU-9 Minimum Outdoor Air


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


16,536 $1,654 14,135 $1,696 1,347 $13,468 $16,818 $8,500 0.5

BASE CASE AHU-9 is a 60,000 cfm variable volume mixed air unit serving the offices and administration areas on Levels 1 - 8. The as-built mechanical schedule for the AHU specifies a minimum outdoor air quantity of 20,000 cfm, or 33%. However, the actual ratio of outdoor air calculated using outdoor, return, and mixed air temperature was 58%. The equation below shows how this ratio is calculated:

% 𝑂𝑢𝑡𝑑𝑜𝑜𝑟 𝐴𝑖𝑟 =(𝑅𝐴𝑇 − 𝑂𝐴𝑇)

(𝑀𝐴𝑇 − 𝑂𝐴𝑇)

Where RAT is return air temperature, MAT is mixed air temperature, and OAT is outdoor air temperature.

PROPOSED CASE This measure proposes to adjust the minimum outdoor air damper position on AHU-9 so that the unit’s minimum outdoor airflow is 11,000 cfm at 100% VFD speed, or approximately 18% of design supply airflow. This is based on the minimum ventilation requirements specified in ASHRAE 62.1-2013, the total floor area served by AHU-9, and the estimated number of occupants in the office areas of the building on a typical day. The following standards and assumptions were used to calculate the minimum ventilation rate:

Total Floor Area Served by AHU-9 = 74,250 ft2

Typical Number of Occupants: 200

Minimum ventilation = 0.06 cfm/ft2 + 5.0 cfm/person = 5,455 cfm

Minimum Observed Fan Speed = 50%

Required Fraction of OA at Min. Fan Speed = 5,455 cfm/(60,000 cfm*50%) = 18.2%

Outdoor Airflow at 100% VFD Speed and 18.2% OA = 60,000 cfm * 18.2% = 11,000 cfm


ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating and cooling energy that is used by reducing the amount of outdoor air that is conditioned when the economizer sequence is disabled.


Base Case

MIN-OUTSIDE-AIR: 0.58

Proposed Case

MIN-OUTSIDE-AIR: 0.182


Figure 90: The trend screenshot below shows the return air temperature (RED), outdoor air temperature (BLUE) and mixed air temperature (PINK) for AHU-9. The two periods highlighted in gray indicate when the mixed air damper’s pneumatic signal (ORANGE) was at minimum and the calculated outdoor air ratio was approximately 58% on average.






(978) 208 - 0609


1 3 Programming ea 1 $0 $150 1 8 $1,200 $1,200

2 3 TAB ea 1 $0 $150 2 4 $1,200 $1,200

3 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $5,400

1 Means







Total $8,500

Opinion of Probable Construction CostECM-18.00 (e)-5: Reduce Minimum Outdoor Air


Sources


ECM-18.00 (E)-6 REPROGRAM AHU-10, 11 ZONE TEMPERATURE

SET-POINTS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-6 Reprogram AHU-10, 11 Zone Temperature Set-points


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


618 $62 3,761 $451 20 $203 $716 $3,900 5.4

BASE CASE AHU-10 and AHU-11 are constant volume fan coil units that recirculate conditioned air to the elevator machine rooms. The AHUs feature chilled water coils that are used to maintain a fixed zone temperature set-point of 72°F (See Figure 91 on Page 340). Since the AHUs serve mechanical spaces, it is possible to have a higher set-point without impacting occupant comfort or lab safety.

PROPOSED CASE The measure proposes raising the zone cooling set-points for AHU-10 and AHU-11 to 80°F to reduce their mechanical cooling energy consumption.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in chilled water energy that is used by maintaining the mechanical spaces served by AHU-10 and AHU-11 at higher temperatures.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on 10L-Mechanical1 Zn (served by AHU-10, 11) and changed the following parameters:

Base Case

COOL-TEMP-SCH: Mech Cool AS

o Monday - Sunday 12:00am - 11:59pm: 72°F

HEAT-TEMP-SCH: Mech Heat AS


Proposed Case

COOL-TEMP-SCH: ECM-18.00-6 Mech Cool AS



HEAT-TEMP-SCH: ECM-18.00-6 Mech Heat AS



Figure 91: The trend screenshot below shows the chilled water valve position (BLUE) and zone temperature (RED) for AHU-10. The chart shows that the zone temperature is maintained at a fixed set-point of 72°F.






(978) 208 - 0609


1 3 Programming ea 2 $0 $150 1 2 $600 $600

3 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $2,400

1 Means







Total $3,900

Sources

Opinion of Probable Construction CostECM-18.00 (e)-6: Reprogram Zone Temperature Set-points



ECM-18.00 (E)-7 REPLACE PREHEAT FACE/BYPASS DAMPER ACTUATORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-7 Replace Preheat Face/Bypass Damper Actuators


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


235,436 $23,544 7,635 $916 3,529 $35,295 $59,754 $14,400 0.2

BASE CASE According to the latest control sequence of operation for the make-up air units (AHU-1 through AHU-8), when the outdoor air temperature is less than 42°F, the preheat valve opens fully and the preheat face/bypass damper modulates to maintain the preheat discharge air temperature set-point. When the outdoor air temperature is greater than 42°F, the dampers open fully to the coil and the coil valve modulates to maintain the discharge air set-point. This sequence is used to prevent coil freezing or freeze stat trips when the outdoor air temperature approaches and is less than the freezing mark. When in the heating mode, the chilled water valve is locked out and cannot open.

Historical trend data available between 9/15/2014 - 10/14/2014 showed four periods when the outdoor air temperature was below 42°F and the preheat sequence described above was activated. However, on AHU-1 and AHU-3, the face/bypass dampers did not properly modulate to maintain the preheat discharge air temperature set-point. The dampers remained fully open to the coil while the preheat valves were open 100%, causing the preheat discharge air temperature to rise significantly. Since the chilled water valve could not open according to the sequence, each make-up air unit’s supply air temperature also increased significantly. This resulted in a rise in zone temperatures and a corresponding rise in airflow; each AHU’s supply fan VFDs went to maximum speed during these instances. Refer to Figure 92 and Figure 93 for examples of this issue.

PROPOSED CASE This measure proposes to replace the preheat face/bypass damper actuators on AHU-1 and AHU-3 so that the units are able to maintain their discharge air set-points when the outdoor air temperature is below 42°F. As part of this measure, the damper linkage and pivots should be inspected for any wear that could contribute to the problem described above.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in preheat energy that is used when the preheat valve opens 100%, but the face/bypass damper does not properly modulate to maintain the preheat discharge air temperature set-point.


The energy savings associated with this measure were estimated using a custom weather-bin spreadsheet model. The baseline model was developed using trend data available from 9/15/2014 - 10/14/2014, when this issue was found to occur four separate times. During these periods, the average temperature rise beyond what was needed to meet the discharge air temperature set-point was approximately 20°F, and was positively correlated with outdoor air temperature. In addition, the baseline model accounts for the increase in fan speed observed as a result of the elevated discharge air temperatures.

In the proposed case model, the face/bypass dampers were assumed to perform as intended, modulating to maintain the necessary discharge air temperature set-point. A proposed case fan speed profile was developed based on other make-up air units serving similar spaces that did not show the preheat face/bypass damper issue.


Figure 92: The trend screenshot below shows two instances where the outdoor air temperature (RED) drops below 42°F and the preheat valve (PINK) goes fully open (2 psig). During this period, the face/bypass damper pneumatic signal (LIGHT BLUE) goes to 14 psig, which indicates fully closed to the coil, but the preheat discharge temperature (DARK BLUE) increase between 70-80°F when it should be below 55°F. This may indicate the face/bypass damper actuator is malfunctioning.


Figure 93: The trend screenshot below shows the same time period as the chart on the previous page. This chart shows the supply fan VFD speeds (RED/BLUE) on AHU-1 when the face/bypass damper remained open to the AHU’s preheat coil, causing the discharge air temperature (ORANGE) to rise significantly above the 55°F set-point (PINK).






(978) 208 - 0609


1 3 Damper Actuator ea 8 $300 $2,400 $150 1 2 $2,400 $4,800

2 3 Damper Linkage Repair ea 2 $0 $150 1 4 $1,200 $1,200

3 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $7,800

1 Means







Total $14,400

ECM-18.00 (e)-7: Replace Preheat Face/Bypass Damper Actuator


Sources



ECM-18.00 (E)-8 EXHAUST FAN STATIC PRESSURE RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-8 Exhaust Fan Static Pressure Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


213,924 $21,392 0 $0 0 $0 $21,392 $6,600 0.3

BASE CASE Historical trend logs show that the static pressure reset on the building’s laboratory exhaust systems is inconsistent. For example, EX-1, 2, 3, and 5 were found to have a demand-based reset with a minimum static set-point of 1.00” WC and a maximum of approximately 1.80” WC. The following is an excerpt from the Siemens control submittal outlining the intended exhaust fan static pressure control sequence:

The maximum damper position for all terminal boxes on the exhaust system is continuously monitored by the DDC system. If the maximum damper position is above 95% open, and the exhaust static set-point is below the maximum set-point, then the duct static pressure set-point shall be incremented by 0.1” WC. If the maximum damper position is less than 75% open, and the exhaust static set-point is above the minimum set-point, then the duct static set-point shall be decremented by 0.1” WC. The increment/decrement decision is executed at 5 minute intervals.

The trend logs show that EX-4 A/B/C had a constant static set-point of 1.8” WC during the month of July and EX-6 A/B/C had a set-point that reset between 1.60” WC and 1.80” WC, but appeared to reset on a schedule instead of based on control feedback. Since all six exhaust systems serve similar areas and are manifolded into two systems at the floor level, it would be expected for all to have similar reset profiles.

It is possible that one or more exhaust boxes connected to EX-4 A/B/C are constantly open more than 95%, causing the static pressure set-point to remain at maximum. This may be caused by a malfunctioning or plugged airflow station, improper balancing or design, improper thermostat location, or very high internal thermal loads, among others.

PROPOSED CASE This measure proposes to investigate the exhaust boxes connected to EX-4 A/B/C to identify rogue zone(s) that may be contributing to the issues observed with the static pressure reset. Once identified, the root cause should be corrected and the results verified to ensure that the static pressure set-point on EX-4 A/B/C is resetting as expected.


This measure also includes investigating the static pressure reset sequence on EX-6 A/B/C to determine if it has been changed from the original sequence based on exhaust box damper position. If so, we propose reprogramming the sequence with minimum and maximum set-points of 1.00” WC and 1.80” WC, respectively.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from a reduction in exhaust fan horsepower needed to maintain a lower duct static pressure set-point when EX-4 A/B/C and EX-6 A/B/C are at part load.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on AHU-4 and AHU-6, and changed the return fan “EIR f(PLR)” performance curve that calculates fan input power as a function of airflow part load ratio. In the baseline eQuest model, the building’s laboratory exhaust fans were modeled as return fans to increase configuration flexibility. The curves used in base case were custom developed to reflect no static pressure reset on EX-4 and a partial reset on EX-6.

In the proposed case, the return fan performance curves for AHU-4 and AHU-6 were replaced to reflect a demand-based reset between 1.00 - 1.80” WC. At minimum fan part load ratio of 30%, the proposed fan energy input ratio (EIR) was 0.2614 compared to an existing EIR of 0.3331 for EX-4 and 0.2873 for EX-6, resulting in 21% savings at lowest part load for EX-4. EIR is defined to be the ratio of electric energy input (Btu/hr) to the rated energy output (Btu/hr) of the fan. The chart on the following page illustrates the existing and proposed can fan curves used to estimate energy savings.



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ECM18.00-8 Static Pressure Reset Curves

EX-4 SP Reset Curve (Existing) EX-6 SP Reset Curve (Existing) Proposed Reset Curve






(978) 208 - 0609


1 3 Programming ea 2 $0 $150 1 8 $2,400 $2,400

2 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $4,200

1 Means







Total $6,600

Sources

Opinion of Probable Construction CostECM-18.00 (e)-8: Exhaust Fan Static Pressure Reset



ECM-18.00 (E)-9 TEMPERATURE SETBACKS IN LAB CORRIDORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-9 Temperature Set-backs in Lab Corridors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


3,465 $346 15,823 $1,899 954 $9,537 $11,782 $19,500 1.7

BASE CASE Historical trend data shows that zone temperature set-points in corridors outside the laboratory spaces are typically 72°F and do not set back at night, similar to the laboratory spaces. See Figure 95 on Page 352 for a chart showing key parameters over time for a typical corridor zone outside the laboratories.

PROPOSED CASE This measure proposes to implement temperature set-backs in the lab corridors to reduce airflow demand during unoccupied periods. The zone set-point would be reset to 78°F in 35 zones on Floors 2 - 9 Monday - Sunday between 8:00pm and 5:30am.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in fan, heating, and cooling energy that is used at the make-up air units and exhaust fans when set-backs can be implemented during unoccupied periods.

The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on all lab corridor zones and changed the following parameters:

Base Case

COOL-TEMP-SCH: S1 Sys1 (PMZS) Cool Sch

HEAT-TEMP-SCH: S1 Sys1 (PMZS) Heat Sch

Proposed Case

COOL-TEMP-SCH: ECM-18.00-9 Corridor Cool Sch

HEAT-TEMP-SCH: ECM-18.00-9 Corridor Heat Sch


Figure 95: The trend screenshot below shows the zone temperature (ORANGE), zone temperature set-point (BLUE), discharge air temperature (RED), and supply airflow (PINK) associated with Room 433R, a corridor zone served by AHU-1 on the 4

th floor. The trend shows that the zone temperature set-point is

constant at 72°F throughout the month of August 2014, and that the supply temperature and airflow are typically consistent as well. The load in this type of zone is primarily driven by equipment such as ultra-low temperature freezers and environmental room compressors and does not fluctuate significantly.






(978) 208 - 0609


1 3 Programming ea 35 $0 $150 1 2 $10,500 $10,500

2 4 As-built ea 1 $0 $150 1 8 $1,200 $1,200


Subtotal $12,900

1 Means







Total $19,500

ECM-18.00 (e)-9: Temperature Setback in Lab Corridors


Sources



ECM-18.00 (E)-10 HOT WATER SUPPLY TEMPERATURE RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (e)-10 Hot Water Supply Temperature Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


-956 -$96 0 $0 4,304 $43,036 $42,940 $6,600 0.2

BASE CASE The hot water supply temperature set-point on the vivarium reheat loop was observed to be fixed at 160°F throughout the spring, summer, and fall. Refer to Figure 96 on Page 356 for a chart showing the loop supply temperatures. Although trend data was not available for the laboratory reheat loop and perimeter radiant panel loop, the control sequences indicate that the lab reheat loop set-point is fixed at 180°F throughout the year and the radiant panel loop is reset based on outdoor air temperature.

PROPOSED CASE This measure proposes to implement a hot water reset on HE-3,4,5, and 6 to reduce distribution losses on the lab and vivarium reheat loops during periods of lower thermal load. During the summer months, a hot water supply temperature of 160°F may not be necessary to satisfy terminal reheat loads. The table below summarizes the proposed reset parameters.

Outdoor Temperature

Vivarium (HE-5,6) HWST Set-point

Lab (HE-3,4) HWST Set-point

°F °F °F

20°F 160°F 180°F

60°F 140°F 160°F


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run was performed on the “Reheat HW Loop” system which models HE-3,4,5, and 6. The following parameters were changed as part of the parametric run.

Base Case

HEAT-SETPT-CTRL: Constant


HEAT-RESET-SCH: n/a

Proposed Case





o Supply Leaving Temp @ Outdoor Low: 160°F (HE-5,6); 180°F (HE-3,4)

o Supply Leaving Temp @ Outdoor High: 140°F (HE-5,6); 160°F (HE-3,4)


Figure 96: The trend screenshot below shows the hot water supply temperature (RED) and supply set-point (BLUE) for HE-5,6 serving the Vivarium reheats.






(978) 208 - 0609


1 3 Programming ea 2 $0 $150 1 8 $2,400 $2,400

2 4 As-built ea 1 $0 $150 1 4 $600 $600


Subtotal $4,200

1 Means







Total $6,600

Sources

Opinion of Probable Construction CostECM-18.00 (e)-10: Hot Water Supply Temperature Reset



OTHER OPPORTUNITIES REVIEWED

CONVERT FUME HOODS TO VAV (84) Of the facility’s total (108) laboratory fume hoods are constant volume units manufactured by Labconco. The majority of fume hoods have been retrofitted with kits that allow for a face velocity of 60-70 feet per minute (fpm) at maximum sash height and have been rebalanced to the airflow level necessary to maintain this design velocity. When researchers close sashes to their minimum positions, the hood face velocity increases since airflow is partially restricted through the hood bypass opening and there is no exhaust flow control.

An analysis of laboratory air change rates and fume hood density has shown that the majority of labs currently have a make-up rate that is driven primarily by air change requirements and not by fume hood exhaust. In addition, the majority of bay lab supply and exhaust VAV boxes are currently at or near the manufacturer’s recommended minimums. As a result, any additional flow reduction at the fume hoods would require retrofitting the VAV and VEV boxes, as described in the ECM 04.09-3 proposed case.

If fume hood exhaust flow rates were reduced by converting to VAV hoods, an analysis of zone level airflow balancing showed that total exhaust in the labs would not change. This is due to the relatively low density of fume hoods in the laboratories compared to the minimum supply airflow required to maintain the necessary air change rates.

A potential VAV hood conversion was also found to have little to no impact on total lab exhaust at the unoccupied period air change rates proposed in ECM-04.09-3. Air change rates would need to be below 2 ACH in most lab areas in order for a VAV fume hood retrofit project to offer net energy savings.

ULTRA-LOW TEMPERATURE FREEZER REPLACEMENT There are numerous low temperature freezers throughout the laboratory areas of the facility that appear to range in age, although many are estimated to be original to the building. We recommend replacing low temperature freezers with Energy Star rated or high efficiency units as equipment reaches the end of its useful life. Energy savings will vary based on existing and new freezer efficiency, condition of the equipment, and the usage characteristics.

359 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Medical School

MEDICAL SCHOOL EXECUTIVE SUMMARY TABLE


ECM # ECM

Electric

Energy

Savings

CHW Energy

Savings

Steam

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


01.01 (f) Lighting Retrofit 799,421 0 0 $79,942 $1,197,300 15.0

03.01 (f)-1 Retrofit FCU & FPB Fans With EC Motors 105,425 0 0 $10,543 $189,200 17.9

03.01 (f)-2 Retrofit Enviro-Room Evap Fans with EC Motors 93,229 0 0 $9,323 $174,400 18.7

04.07 (f) Upgrade Terminal VAV Mixing Box Controls 693,873 102,433 624 $87,919 $1,827,525 20.8

09.00 (f)-1 Loading Dock Variable Exhaust Controls 317,926 0 0 $31,793 $74,315 2.3

09.00 (f)-2 Reduce Lab Air Changes 1,108,663 505,892 7,047 $242,044 $807,463 3.3

09.00 (f)-3 Install VFDs & CO2 Ventilation Controls on Library ACs 300,790 70,026 2,172 $60,203 $139,565 2.3

17.09 (f) Reclaim Return Air on AC-12 8,483 0 659 $7,442 $39,600 5.3

18.00 (f)-1 Optimize Perimeter HW Reset 0 0 387 $3,874 $31,000 8.0

18.00 (f)-2 Auditorium Scheduling & Occupancy Controls 249,081 32,778 1,234 $41,182 $202,950 4.9

18.00 (f)-3 Repair Heating Valves & Actuators 0 220,569 5,274 $79,206 $59,050 0.7

18.00 (f)-4 Repair Cooling Valves & Actuators 0 74,420 173 $10,656 $18,250 1.7

18.00 (f)-5 Repair Economizer Dampers & Optimize Sequence 61,505 639,057 7,186 $154,700 $259,900 1.7

18.00 (f)-6 Air Sealing Repairs on AC Units 276,499 20,259 -777 $22,310 $442,100 19.8

18.00 (f)-7 Optimize Static Pressure Reset 30,479 7,096 -7 $3,826 $27,800 7.3

21.02 (f) School Solar Hot Water 0 0 929 $9,288 $338,601 36.5

School Subtotals 4,045,373 1,672,529 23,972 $844,962 $5,490,418 6.5

School Building



The University of Massachusetts Medical School (UMMS) building is approximately 900,000 ft2 and was built in the early 1970’s with 10 above grade stories and 2 below grade levels. The above ground Levels 1 – 7 are used for a mixture of research, education, and administrative purposes, with levels 8 - 10 used primarily for mechanical equipment. This facility contains numerous lab areas used for various research and educational purposes, a two-story library and study area, three large auditoriums, and an entry foyer open to multiple levels. The west wing area is referred to as the “Basic” wing, the east wing is referred to as the “Clinical” wing, and the section connecting the Basic and Clinical wings is known as the “Student” wing. The “clip-on” façade space addition was completed approximately 10 years ago and added space to the south side of the building including the lobby area. Sub-level A contains the animal quarters and other research areas and sub-level B is primarily facility engineering/mechanical support space and loading dock area. Some lab spaces in the building have been or are currently being renovated and changed to office areas, primarily in the student wing. The building is occupied 24 hours a day. Some areas have daily schedules, while many research labs and offices can be occupied at any time. Auditorium and library occupancy is variable depending on class schedules. Along with electricity, the campus power plant also supplies chilled water and high pressure steam, which is converted to low pressure steam for heating use.

There are approximately (42) air handling systems, referred to as AC units, that serve the building. Among these, (6) are 100% outside air units. Approximately (25) AC units are dual-duct, and are original to building construction, while the remaining units are single duct and many of these were added after original construction. Most AHUs are zoned vertically, meaning they serve spaces on different floors from 1 – 7 and in most cases the spaces served by a single AC unit are stacked on top of each other. Most ACs serve both lab and office areas as a result of this vertical zoning arrangement. AC units typically have a steam or Hot Water (HW) preheat coil, a hot deck steam or HW coil for heating and a cold deck Chilled Water (CHW) coil. Some ACs are mixed air units and do not have preheat coils. Most ACs are equipped with Variable Frequency Drives (VFDs) that are controlled to meet a static pressure set-point, except for (8) ACs which do not have VFDs. Some ACs are dedicated to environmentally-controlled and containment/pressure isolation spaces. There are several 100% outside air systems providing makeup air to labs and other areas. AC units that are not 100% OA are equipped with return fans and return air from office areas. See the appendix for AC unit details.

The dual-duct ACs serve approximately (900) terminal dual-duct mixing boxes throughout the building. Roughly half are constant volume mixing boxes with one damper that provides a proportion of hot deck and cold deck air which varies based on the zone cooling or heating demand. The other half of the dual duct boxes are Variable Air Volume (VAV) boxes, with individually actuated hot and cold deck dampers. The “clip-on” façade ACs primarily serve single duct VAV fan powered boxes with HW reheat. The animal quarters is the only building area where humidification is used, with humidifiers located both directly in the respective spaces and in AC-5 (100% OA MAU).


The exhaust duct risers are zoned vertically in a similar fashion to the AC units, and exhaust from both lab hoods and general lab exhaust ducts. Lab area ventilation is once-through; meaning 100% of the air supplied to the space is exhausted. However, the labs are not 100% OA since the AC units supply air to the labs that is mixed with return air from the offices areas. There are approximately (70) fume exhaust hoods in the lab areas, and most are from original construction and are constant volume. The air change/hour rate (ACH) for labs appears to be in 7 – 8 ACH range, except for labs which were renovated and had been designed for 6 ACH by UMMS engineering staff. Half of the approximately (50) exhaust fans are equipped with VFDs that control to maintain a negative duct static pressure set-point.

Each floor contains perimeter Hot Water Base Board divided into four zones based on compass direction. The south zone is no longer in use due to space overheating issues. Each zone is served by a pump with a 5hp, premium efficiency motor. This system is enabled below 38oF. The HW is heated by steam converters. There is also a HW reheat loop serving the “clip-on” VAVs and AC units with HW coils. Domestic HW is provided by a system of semi-instantaneous steam water heaters.

ACs are primarily controlled by pneumatic operators overlaid with legacy Johnson DX-9100 controllers. The DX-9100 controllers are mapped to the Automatic Logic Controls (ALC) digital BAS. The ALC BAS controls the AC unit schedules and sequences. Most AC unit sequences include OA dry-bulb based economizer, cold deck and hot deck supply air temperature reset, and some AC units have static pressure set-point reset. Compressors located in the mechanical spaces provide control air to the ACs as well as to many of the terminal mixing boxes. Approximately 25% of the VAV dual duct mixing boxes are digitally controlled and are on the ALC BAS, while the remaining 75% are pneumatically controlled and are not on the BAS.

Approximately (30) refrigerated environmental rooms are located within the building. Waste heat from the compressors serving these rooms is removed by the condenser water loop, via a heat exchanger with the building CHW loop. Condenser water loop is served by (3) 3 hp inline pumps. The building also contains extensive medical lab and research equipment, such as laboratory vacuum pumps, air compressors, and incubators, and more than 100 chest and cabinet-type refrigerators and low-temperature freezers.

The lighting in the facility consists primarily of 2’ by 4’ one-, two-, and three-lamp 32 Watt T8 fluorescent fixtures. There is also a significant quantity of 1’ by 8’ two- and four-lamp 32 Watt T8 fluorescent fixtures, 65 Watt incandescent flood lights in recessed and pendant cans, and 26 and 18 Watt two-lamp compact fluorescent lamps (CFLs) in recessed and pendant cans. The remaining lighting consist of 2’ by 2’ two- and three-lamp 17 Watt T8s, 1’ by 12’ three-lamp 32 Watt T8s, and 1’ by 3’ one-lamp 25 Watt T8s. The lens type on most of the fluorescent fixtures is prismatic, parabolic, or volumetric. With the exception of the 1st floor lobby and common areas, and the Student Affairs area, the recessed and pendant CFL and incandescent flood lights do not have a lens.



ENERGY USE GRAPHS

ELECTRICITY Figure 64 on the following page shows electricity use for the School Building for FYs 11 – 14. It can be seen that electricity use is fairly consistent throughout each given year, with slight variations between the years likely due to weather effects. It can also be seen that there is a monthly decrease of about 300,000 kWh between FY12 and FY13-14, possibly occurring because of changes in use profiles, building lighting or equipment upgrades or scheduling changes, or it may be due to some other reason.

Figure 65 shows the electric use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 97: Medical school monthly electricity use (kWh) for Fiscal Years 2011 - 2014.

Figure 98: Medical school baseline electricity use (kWh) profile, using averaged monthly data from Fiscal Years 2011 - 2013 that has been corrected to reflect the savings associated with the lighting retrofit in the adjacent parking garage.

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STEAM Figure 66 shows the monthly steam consumption for FYs 11 – 14. In FY12-13, some pronounced variations can be seen between months, possibly due to differentials in meter read dates. It can also be seen that FY 14 has a noticeably higher consumption during the winter months. This increase was not seen in previous years and was therefore excluded from the baseline.

Figure 67 shows the steam use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unavailable at the time of this report.


Figure 99: Medical school monthly steam energy use (Lbs) for Fiscal Years 2011 - 2014.

Figure 100: Medical school baseline steam energy use (Lbs) profile, including averaged monthly data from Fiscal Years 2011 - 2013 .

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CHILLED WATER Figure 68 shows the Medical School’s CHW use from FYs 11 – 14. It can be seen that CHW use is fairly consistent from year to year, with slight variations between years likely due to weather effects.

Figure 69 shows the CHW use averaged over FYs 2011-2013, taken as the utility use baseline for energy model calibrations. FY2014 was excluded from the baseline due to the fact that complete data for that fiscal year was unable at the time of this report.


Figure 101: Medical School monthly chilled water energy use (ton-days) for Fiscal Years 2011 - 2014.

Figure 102: Medical School baseline chilled water energy use (ton-days) profile, using averaged monthly data from Fiscal Years 2011 - 2013.

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BENCHMARKING

BENCHMARKING SUMMARY TABLE The table below summarizes the annual energy consumption and performance metrics for the facility. This was done to provide a clear representation of the actual site energy consumption for benchmarking and also for evaluation with energy savings opportunities. Energy use data for fiscal years 2011 – 2013 is shown below, along with an average of data from the three fiscal years.

Energy Use


Performance Ratings




ft2 FY kWh ton-hrs klbs

kWh

/ft2

W

/ft2

kBtu

/ft2

kBtu

/ft2

kWh

/ft2

kBtu

/ft2

kBtu

/ft2

kWh

/ft2

kBtu

/ft2

kBtu

/ft2

kBtu

/ft2

FY11 21,377,650 7,739,280 127,202 23.6 2.70 80.6 102.61 5.5 12.2 141 0 176 324 287

FY12 22,356,540 7,068,552 101,304 24.7 2.82 84.3 93.71 5.0 11.2 112 0 140 290 252

FY13 19,710,590 6,678,024 122,804 21.8 2.49 74.3 88.54 4.7 10.5 136 0 170 299 271

3 Year Avg. 21,148,260 7,161,952 117,103 23.4 2.67 79.7 94.95 5.1 11.3 129 0 162 304 270

UMass Medical Center School Building Energy Use Data

905,127

CHW Steam Total

Source Source

BLDG INFO ENERGY USE PERFORMANCE RATINGS

Floor

AreaFiscal Year Electricity CHW

50#

SteamElectricity






The total site and source performance ratings sum the equivalent source ratings (kBtu/ft2) for electricity, chilled water, and steam,

so that this building can be benchmarked against similar facilities, which may generate steam and chilled water in a central plant

captured in the building electricity and natural gas meters.


BENCHMARKING COMPARISON This chart compares the School Building with total site kBtu/ft2 averages for several New England academic lab buildings.

In order to compare each of the buildings’ energy use benchmarks, all electricity, chilled water, and steam energy consumption was converted to estimated equivalent source energy (kBtu). For example, Academic Lab 1 is supplied steam and chilled water from district systems, but Academic Labs 2 and 3 have on-site chiller plants and district steam. As a result, a direct site electricity use comparison between these buildings and the UMMS could be misleading.

The table above shows that the UMMS source kBtu/ft2 is higher than all three of the comparison buildings by 10% on average. The kBtu/ft2 metric indicates that the school building is more energy intensive when compared to other academic buildings featuring lab space. Two additional site benchmarks are included in the table: Site Electricity Use Intensity (kWh/ft2) and Average Electric Demand (W/ft2). Average Electric Demand is calculated by dividing the building’s annual electricity consumption by 8,760 hours/year, and multiplying by 1000 W/kW to determine the annual average demand at the facility. It can be seen that the W/ft2 and kWh/ft2 performance metrics are approximately 30% lower for the school building than for other New England academic labs on average, however the kBtu/ft2 performance metric for the school building is 10% higher than the average for selected academic lab areas in this climate zone. This difference is likely due to the chilled water consumption which is included in the kBtu/ft2 metric and not in the site electric use metric for the school building. This combined with the electric use metrics suggest that there is an opportunity for energy savings in the school building by reducing simultaneous heating and cooling energy use resulting from the existing dual duct AHU systems.

New

England

Academic

Lab 1

New

England

Academic

Lab 2

New

England

Academic

Lab 3

Average

of

Lab 1-3

UMMC

School

Building

Gross Area (ft2) 132,998 178,612 81,304 130,971 905,127

Approximate Lab Area % 40% 40% 80% 53% 40%

Total Site kBtu/ft2289 260 271 273 304

kWh/ft237.6 32.5 26.7 32.3 21.8

Average W/ft24.3 3.7 3.0 3.7 2.5



Energy and cost savings were estimated using an existing eQuest model of the facility originally developed by Andelman & Lelek and modified to reflect current equipment characteristics, schedules, and internal loads. The model used the TMY3 weather file for Worcester, MA and was calibrated against monthly electricity use over a three year period from July 2010 – July 2013. The model was also calibrated for chilled water and steam use using monthly data obtained from the UMass central plant staff. The charts below compare the baseline utility use and the calibrated eQuest model predicted utility use.

Figure 103: Medical School eQuest model electricity use calibration chart. The baseline monthly electricity use utility data is shown in blue and the eQuest model predicted monthly electricity consumption is shown in red.

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

3,000,000

Ele

ctri

city

Usa

ge (

kWh

)


UtilityData

eQUESTOutput


Figure 104: Medical School eQuest model chilled water calibration chart. The baseline monthly chilled water utility data is shown in blue and the eQuest model predicted monthly chilled water energy consumption is shown in red. The divergence in the summer months is due to eQuest’s limitations in modeling economizer issues.

Figure 105: Medical School eQuest model steam calibration chart. The baseline monthly steam utility data is shown in blue and the eQuest model predicted monthly steam consumption is shown in red.

0

5,000

10,000

15,000

20,000

25,000

Ste

am U

sage

(M

lb)

Monthly Steam Usage

UtilityData

eQUESTOutput


The table below summarizes the annual end-use energy distribution for electricity, steam, and chilled water at the facility as calculated by the baseline eQuest model. The pie chart below illustrates the baseline eQuest model’s electricity end use using the figures shown in the table.


The following parameters were used to model the estimated miscellaneous loads in the School building, based on information gathered during walkthroughs and historical whole-building electricity use:

6. Corridor Plug Loads: 0.1 W/ft2

7. Office, Conference Room, Lecture Hall Plug Loads: 0.5 - 0.75 W/ft2

8. Laboratory Plug Loads: 3.0 W/ft2



4. Corridor, Conference Room, Classroom, Library Lighting Power Density: 0.90 - 1.00 W/ft2

5. Laboratory Lighting Power Density: 1.20 W/ft2

Table 11: Medical School eQuest model’s annual energy end-use for each meter (electricity, steam, and chilled water).

kWh Mlb ton-hrs



Refrigeration 0 0 0


Heat Pump 0 0 0

Hot Water 0 0 0


Pumps and Auxiliary 1,663,674 0 0

Exterior 0 0 0

Miscellaneous Equipment 3,175,875 2,196 0

Task Lighting 0 0 0


Total 21,535,787 115,591 6,827,900

Annual Energy by End

Use

Baseline Energy Use


Figure 106: Pie chart showing the Medical School eQuest model’s annual electricity end use breakdown.

Area Lighting 23%

Miscellaneous Equipment

15%

Pumps and Auxiliary 8%

Ventilation Fans 54%

Baseline Model Annual Electricity End Uses


ECM 1.01 (F) LIGHTING RETROFIT

MEASURE ECONOMICS SUMMARY ECM # 01.01 (f) Lighting Retrofit


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


799,421 $79,942 0 $0 0 $0 $79,942 $1,197,300 15.0

BASE CASE The lighting in the facility consists primarily of 2’ by 4’ one-, two-, and three-lamp 32 Watt T8 fluorescent fixtures. There is also a significant quantity of 1’ by 8’ two- and four-lamp 32 Watt T8 fluorescent fixtures, 65 Watt incandescent flood lights in recessed and pendant cans, and 26 and 18 Watt two-lamp compact fluorescent lamps (CFLs) in recessed and pendant cans. The remaining lighting consist of 2’ by 2’ two- and three-lamp 17 Watt T8s, 1’ by 12’ three-lamp 32 Watt T8s, and 1’ by 3’ one-lamp 25 Watt T8s. The lens type on most of the fluorescent fixtures is prismatic, parabolic, or volumetric. With the exception of the 1st floor lobby and common areas, and the Student Affairs area, the recessed and pendant CFL and incandescent flood lights do not have a lens.

UMass recently upgraded lighting in three buildings on campus, with the entire project consisting of approximately 10,000 28 Watt T8 lamps. An estimated 2,300 of these were dedicated to the Medical School. UMass staff re-lamped a large portion of the fluorescent fixtures that are on during all hours of the year in the halls, entryways, and common areas.

PROPOSED CASE This measure proposes to upgrade existing lamps and ballasts to newer high efficiency units where applicable. Refer to the Opinion of Probable Cost Table on the following page for a breakdown of proposed equipment types and quantities. We recommend replacing 4’ 32 Watt T8 lamps with high efficiency 28 Watt lamps and NEMA Premium (NP) electronic ballasts. We also recommend replacing CFLs and incandescent floods with LED lamps and installing occupancy sensors in some offices. The recommendations do not include fixture upgrades or replacement in an effort to present a more cost effective retrofit approach.




ASSUMPTIONS

A room-by-room lighting audit was performed on 1st, 2nd, and 3rd floors. A higher level, detailed walk-through audit was performed on the 4th through 8th floors. The primary approach to the walk-through audit was to confirm the information from the 1996 audit, and if different, capture those changes and include them in the report. Most of Level A was not accessible. What we could access to mirrored the 1996 audit information, so we used 1996 audit data for the report. We were unable to access Floors 9 and 10. We again used the 1996 data for floors 9 and 10 for the report. Lighting controls have been included in the kWh savings methodology. The recent T8 fluorescent re-lamping project occurred simultaneously with this energy audit. The counts, savings, and costs in this report have been updated from the 50% draft report based on anecdotal input from UMass since new lighting plans are not available at this time.


COST ESTIMATE

Note: The numbers in red in the table above indicate changes from the 50% report to account for the recent lighting upgrades.

Item Source Item Type Qty

Unit

Cost Total Cost

Unit

Rate Workers

Hours

Each

Labor

Cost Total Cost

1 3-Audit Retrofit - 2 Lamp 4 foot 32 Watt T8 with NP Ballast with 2 Lamp 4 foot 28 Watt T8 with NP Ballast ea 5,279 $55 $290,345 $0 0 0 $0 $290,345

2 3-Audit Retrofit - 1 Lamp 4 foot 32 Watt T8 with NP Ballast with 1 Lamp 4 foot 28 Watt T8 with NP Ballast ea 1,098 $45 $49,410 $0 0 0 $0 $49,410

3 3-Audit Retrofit - 2 Lamp 4 foot 32 Watt T8 with LP Ballast with 2 Lamp 4 foot 28 Watt T8 with LP Ballast ea 136 $55 $7,480 $0 0 0 $0 $7,480

4 3-Audit Retrofit - 3 Lamp 4 foot 32 Watt T8 with NP Ballast with 3 Lamp 28 Watt T8 with NP Ballast ea 1,604 $60 $96,240 $0 0 0 $0 $96,240

5 3-Audit Retrofit - 1 Lamp 2 foot 17 watt T8 with NP Ballast with 1 Lamp 2 foot 17 watt T8 with LP Ballast ea 112 $45 $5,040 $0 0 0 $0 $5,040

6 3-Audit Retrofit - 4 Lamp 4 foot 32 Watt T8 with NP Ballast with 4 Lamp 4 foot 28 Watt T8 with NP Ballast ea 67 $65 $4,355 $0 0 0 $0 $4,355

7 3-Audit Retrofit - 2 Lamp 2 foot 17 Watt T8 with NP Ballast with 2 Lamp 2 foot 17 Watt T8 with LP Ballast ea 35 $55 $1,925 $0 0 0 $0 $1,925

8 3-Audit Retrofit - 1 Lamp 3 Foot 25 Watt T8 with NP Ballast with 1 Lamp 3 Foot 25 Watt T8 with LP Ballast ea 49 $45 $2,205 $0 0 0 $0 $2,205

9 3-Audit Retrofit 3 Lamp 2 Foot 17 Watt T8 with NP Ballast with 3 Lamp 2 Foot 17 Watt T8 with NP Ballast ea 199 $60 $11,940 $0 0 0 $0 $11,940

10 3-Audit Retrofit - 6 Lamp 4 foot 32 Watt T8 with NP Ballast with 6 Lamp 4 Foot 28 Watt T8 with NP Ballast ea 4 $65 $260 $0 0 0 $0 $260

11 3-Audit Replace 13 Watt Compact Florescents lamps (CFL's) with 5 Watt LED's ea 7 $5 $35 $0 0 0 $0 $35

12 3 Audit Replace 18 Watt Compact Florescents lamps (CFL's) with 9 Watt LED's ea 48 $5 $240 $0 0 0 $0 $240

13 3 Audit Replace 26 Watt Compact Florescents lamps (CFL's) with 13 Watt LED's ea 385 $5 $1,925 $0 0 0 $0 $1,925



16 3 Audit Replace 65 Watt Incandescent Flood lamps with 32 Watt LED's ea 490 $5 $2,450 $0 0 0 $0 $2,450

17 3 Audit Retrofit - 1 Lamp 8 foot high output 32 watt T8 with NP Ballast with 1 Lamp 8 foot 28 watt T8 with NP Ballast ea 15 $55 $825 $0 0 0 $0 $825

18 3 Audit Retrofit - 2 Lamp 8 foot 32 watt T8 with NP Ballast with 2 Lamp 8 foot 28 watt T8 with LP Ballast ea 687 $65 $44,655 $0 0 0 $0 $44,655

19 3 Audit Retrofit - 2 Lamp 8 foot T12's with Magnetic Ballast with 2 Lamp 8 foot 28 watt T8 with NP Ballast ea 221 $65 $14,365 $0 0 0 $0 $14,365

20 3 Audit Retrofit - 4 Lamp 8 foot 32 watt T8's with NP Ballast with 4 Lamp 8 foot 28 watt T8 with LP Ballast ea 326 $65 $21,190 $0 0 0 $0 $21,190

21 3 Audit Retrofit - 1 Lamp 2 foot 20 watt T12's with HP Ballast with 1 Lamp 2 foot 17 watt T8's with NP Ballast ea 60 $45 $2,700 $0 0 0 $0 $2,700

22 3 Audit Retrofit - 2 Lamp 3 foot 25 watt T8's with NP Ballast with 2 Lamp 3 foot 25 watt T8's with LP Ballast ea 56 $55 $3,080 $0 0 0 $0 $3,080

23 3 Audit Retrofit - 2 Lamp 3 foot 25 watt T8's with LP Ballast with 2 Lamp 3 foot 14 watt T5's with NP Ballast ea 76 $55 $4,180 $0 0 0 $0 $4,180

24 3 Audit Retrofit - 1 Lamp 4 foot 25 watt T8's with NP Ballast with 1 Lamp 4 foot 25 watt T8's with LP Ballast ea 12 $45 $540 $0 0 0 $0 $540

25 3 Audit Wall Switch Occupancy Sensors ea 867 $90 $78,030 $0 0 0 $0 $78,030

$643,500

1 Means Contingency 20% $128,700

2 Vendor Quote Engineering 15% $115,900

3 Other Construction Administration 5% $38,700

4 Vendor Allowance Commissioning 20% $154,500



Total $1,197,300

Sources Subtotal



ECM 3.01 (F)-1 RETROFIT FCU & FPB FANS WITH EC MOTORS

MEASURE ECONOMICS SUMMARY ECM # 03.01 (f)-1 Retrofit FCU & FPB Fans With EC Motors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


105,425 $10,543 0 $0 0 $0 $10,543 $189,200 17.9

BASE CASE There are an estimated 120 fan coil units (FCUs) and fan powered boxes (FPBs) in the school building, all of which are equipped with either permanent split capacitor (PSC) or shaded pole (SP) AC fan motors. This includes FCUs in data closets. According to available documentation, FPBs range in airflow capacity from 800 to 1,200 cfm, and feature motors ranging from 1/4 to 1/3 nominal hp. Fractional horsepower PSC and SP motors such as these typically operate at efficiencies between 30-60% and do not have speed modulation capabilities. Interviews with facility staff revealed that the majority of fans run continuously (estimated to be 96), as only a few zones in the building have setbacks.

PROPOSED CASE This measure proposes to replace the 96 existing FPB and FCU motors that run continuously with high-efficiency, electronically-commutated (EC) motors. These motors have significantly increased fan efficiency, approximately 20% higher than PSC motors and 30% higher than SP motors.

ENERGY SAVINGS METHODOLOGY This measure results in fan energy savings at all times when the FPBs and FCUs are in operation due to increased motor efficiency.

This measure was modeled using one-line spreadsheets for each unit. Both the existing and proposed case FCU and FPB energy use was calculated by estimating that each fan runs 100% of the time during occupied periods and that the fans run at full speed whenever active. The calculation also assumes fixed motor efficiencies based on the motor size. Figure 107 below summarizes the efficiency curves used to define each motor’s power consumption.


Figure 107: Chart showing differences in nominal efficiency between PSC, SP, and EC motors for several common motor sizes.

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

0 1/10 1/5 3/10 2/5 1/2 3/5

Mo

tor

Effi

cie

ncy

Motor Nominal Power (hp)

FCU & FPB Motor Efficiencies

Shaded Pole Eff

Perm. Split Cap.

EC Motor


COST ESTIMATE The costs for this measure include the materials and labor to replace each FCU’s and FPB’s motor with an EC motor.


100 Burtt Rd. Ste. 212 Address: Medical School Estimated By: JD


(978) 208 - 0609

Total


1 3 New ~1/4HP EC Motors ea 96 $450 $43,200 $150 1 4 $57,600 $100,800

2 3 Testing and Balancing ea 96 $0 $150 1 1 $14,400 $14,400

3 3 As-built ea 1 $0 $150 1 24 $3,600 $3,600

4 3 Contractor Commissioning Labor ea 96 $0 $150 1 0.5 $7,200 $7,200

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $126,000

1 Means




Notes Commissioning 5% $7,600



Total $189,200

Opinion of Probable Construction CostECM 3.01 (f)-1: Retrofit FCU& FPB Fans With EC Motors


Sources


ECM 3.01 (F)-2 RETROFIT ENVIRONMENTAL ROOM EVAPORATOR FANS

WITH EC MOTORS

MEASURE ECONOMICS SUMMARY ECM # 03.01 (f)-2 Retrofit Environmental Room Evaporator Fans with EC motors


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


93,229 $9,323 0 $0 0 $0 $9,323 $174,400 18.7

BASE CASE There are an estimated 30 environmental rooms in the school building, all of which are equipped with either permanent split capacitor (PSC) or shaded pole (SP) evaporator fan motors. These motors are estimated to be fractional or small horsepower and there may be at least two evaporator fans per environmental room. Fractional horsepower PSC and SP motors such as these typically operate at efficiencies between 30-60%. These fan motors run continuously to cool the environmental rooms.

PROPOSED CASE This measure proposes to replace the evaporator fan motors with high-efficiency, electronically-commutated (EC) motors. These motors have significantly increased fan efficiency, approximately 20% higher than PSC motors and 30% higher than SP motors. This measure requires the replacement of each fan motor. Prior to implementation, an inventory of the evaporator fan motors must be taken to determine final costs and savings. A strategy must be developed to mitigate impact on the materials or samples stored in the coolers during implementation. Consideration should be taken if any environmental rooms are anticipated to be decommissioned in the next 5 – 10 years.

ENERGY SAVINGS METHODOLOGY This measure results in fan energy savings at all times when the motors are in operation due to increased efficiency. This measure also results in cooling energy savings by reducing the amount energy from the motors that is added to the environmental room in the form of heat.

This measure was modeled using one-line spreadsheets for each environmental room. Both the existing and proposed case evaporator fan energy use was calculated assuming that each fan runs 100% of the time. The fixed motor efficiencies used in the calculation are based on an assumed motor size of ¼ hp, typical for refrigerated cooler applications. Two fans are assumed in each environmental room for redundancy. Figure 107 in the previous section summarizes the efficiency curves used to define each evaporator fan’s motor power consumption.


COST ESTIMATE The costs for this measure include the materials and labor to replace each evaporator fan motor with an EC motor.


100 Burtt Rd. Ste. 212 Address: Medical School Estimated By: JD


(978) 208 - 0609

Total


1 3 New ~1/4HP EC Motors ea 60 $450 $27,000 $150 1 8 $72,000 $99,000


3 3 As-built ea 1 $0 $150 1 24 $3,600 $3,600

4 3 Contractor Commissioning Labor ea 60 $0 $150 1 0.5 $4,500 $4,500

5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $116,100

1 Means







Total $174,400

Opinion of Probable Construction CostECM 3.01 (f)-2: Retrofit Environmental Room Evaporator Fans With EC Motors


Sources


ECM 4.07 (F) UPGRADE TERMINAL VAV MIXING BOX CONTROLS

MEASURE ECONOMICS SUMMARY ECM # 04.07 (f) Upgrade Terminal VAV Mixing Box Controls


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


693,873 $69,387 102,433 $12,292 624 $6,240 $87,919 $1,827,525 20.8

BASE CASE There are approximately 450 terminal dual-duct VAV mixing boxes which have pneumatic controls. These mixing boxes serve corridors, offices, storage areas, elevator lobbies, etc.; laboratory terminal boxes are not included in this measure. The VAV box pneumatic operators modulate the cold and hot deck dampers independently to mix and provide heating or cooling air flow based on heating or cooling demand. Cold deck and hot deck air flow minimums are approximately 25% - 30% of maximum design flow depending on the box. Table 12 below gives an example of two mixing boxes and their prescribed flow minimums. The air handlers serving the dual duct mixing boxes, provide hot deck temperatures which reset from 80-100°F and cold deck temperatures which reset from 55-60°F. The resets are based on outside air temperature.

Table 12: Flow characteristics of existing mixing boxes

Box #

Cold Deck

Design Flow

Cold Deck

Minimum Flow

Cold Deck Minimum

Flow Ratio

Hot Deck Design Flow

Hot Deck Minimum

Flow

Hot Deck Minimum Flow Ratio

CFM CFM - CFM CFM - MB16-*1-55 350 110 31% 350 110 31% MB16-*1-56 160 40 25% 160 40 25%

With a dual duct system, there is always some inherent level of simultaneous heating and cooling happening. The existing damper setup and existing pneumatic controls allow for an excessive amount of simultaneous heating and cooling. For instance, during peak cooling periods when 100% cold deck air is being provided, there will still be a minimum 25% of the hot deck air flow at 80°F. Alternately, during the peak heating periods when the hot deck is full open, there will still be minimum 25% of the cold deck airflow being provided at 60oF.

The mixing boxes are not controlled to a schedule and have no night setback except for areas where the supply AC unit is scheduled off.


Another source of simultaneous heating and cooling is the interaction of the perimeter HW loops and the VAV cooling operation. The perimeter heat has no control on the system level and is enabled below 38oF with a temperature reset. Facility staff noted that since there is no zone-level control, some zones with perimeter HW are overheating at times. The dual-duct VAV boxes are controlled via a separate pneumatic wall thermostat that will cause the unit to modulate into cooling mode to maintain the space temperature when spaces overheat. This interaction may be a contributing factor to the building’s winter CHW consumption.

PROPOSED CASE The proposed case is to upgrade the mixing box controls to Direct Digital Control (DDC) by retrofitting with new damper actuators, discharge air temperature sensor, and space temperature sensor. The new DDC mixing box controls will be networked into the Automated Logic building automation system. This could be accomplished by overlaying the DDC on the existing pneumatic controls using electric-pneumatic (E-P) transducers or by installing electronic actuators.

The energy savings are a result of more advanced and precise control, allowing flow minimums of 0% when the box is in full cooling or heating mode and for implementation of advanced scheduling and start time optimization. This will also reduce simultaneous heating and cooling from perimeter VAVs calling for cooling in spaces that are overheated by the perimeter HW radiation.

Minimum air flows will be checked so that adequate ventilation air is always provided during occupied periods. The new controls will also allow temperature setbacks to be scheduled in offices (64°F (Heating) / 78°F (Cooling)) when unoccupied. Digital space temperature sensors can be installed with or without the user-occupancy override function. These VAVs will be added to the BAS graphics, and operators will be able to view space temperatures and hot deck/cold deck damper positions. This upgrade will also include historical trending capabilities that are useful for diagnosing issues and optimizing operation.

ENERGY SAVINGS METHODOLOGY A ‘Global Parameter’ in eQuest was used to assign a hot deck minimum flow of 0.3. The Global Parameter, ‘DD Heating Min’, was assigned at the zonal level for all offices that are served by a dual-duct system and still have pneumatic control on the terminal mixing box. A parametric run was created to change the global parameter from 0.3 to 0.0. This will allow the hot deck side of the terminal mixing box to modulate down to its 0% open position as cooling demand increases.


COST ESTIMATE


100 Burtt Rd. Ste. 212 Address: Medical School Estimated By: KK


(978) 208 - 0609

Total


1 3 Actuator (2 per mixing box) ea 900 $250 $225,000 $150 1 1 $135,000 $360,000

2 3 DDC VAV box controller (note 1) ea 450 $500 $225,000 $150 1 2 $135,000 $360,000

3 3 Space Temperature ea 450 $100 $45,000 $150 1 1 $67,500 $112,500

4 BAS Points & Programming ea 450 $500 $225,000 $150 1 2 $135,000 $360,000

5 As-Builts ea 450 $0 $150 1 0.25 $16,875 $16,875

6 Contractor Commissioning Labor ea 450 $0 $150 1 0.5 $33,750 $33,750

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $1,243,125

1 Means




Notes 1 NORESCO project = ~450 VAV boxes Commissioning 5% $74,600

2 DDC controller to have 2 DO for dampers, 1 DA, 1 Space temp Construction Observation 5% $74,600

Project Closeout & Expenses 2.5% $37,300

Total $1,827,525

Opinion of Probable Construction CostECM 04.07 (f): Upgrade Terminal VAV Mixing Box Controls


Sources


ECM 9.00 (F)-1 LOADING DOCK VARIABLE EXHAUST CONTROLS

MEASURE ECONOMICS SUMMARY ECM # 09.00 (f)-1 Loading Dock Variable Exhaust Controls


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


317,926 $31,793 0 $0 0 $0 $31,793 $74,315 2.3

BASE CASE SF-1 provides unconditioned ventilation air to the loading dock, which is exhausted by EF-36. Both fans are constant volume and do not have VFDs. Table 13 below shows the fan & motor characteristics of this equipment. These fans operate 8,760 hours per year to ventilate the loading dock.

Table 13: Loading dock supply & exhaust fan design data

Motor HP Motor kW Airflow CFM

SF-1 30.0 27.0 53,622 EF-36 40.0 36.1 69,366

PROPOSED CASE This measure proposes to implement carbon monoxide (CO) based ventilation controls for the loading dock. This system will adjust the ventilation rate to meet the levels needed based on vehicle and equipment emissions, controlling to the actual activity in the space. This measure includes installing VFDs and premium efficiency motors on SF-1 & EF-36, a CO sensor network in the loading dock to monitor CO levels, and a programmable controller. The VFDs would be programmed to ramp the fans down to provide a minimum ventilation rate when the CO levels inside the loading dock are below set-point. The VFDs would ramp up to increase ventilation air flow when CO levels increase, indicating that equipment or vehicles are operating in the loading dock. Programming can be incorporated to provide different levels of VFD response and alarming when lower/higher levels of CO are sensed. The fans could also be programmed to turn completely off when low levels of CO allow.

ENERGY SAVINGS METHODOLOGY The energy savings for this measure were calculated using a spreadsheet model. Equipment data obtained on site visits and from NORESCO audit motor survey was used in the calculations. The proposed case energy use is calculated using a ventilation air flow profile that is based on


assumed loading dock activities. Proposed case motor input power is calculated using the formula below:

𝑘𝑊𝐼𝑛𝑝𝑢𝑡,𝑉𝐹𝐷 = 𝑘𝑊𝑀𝑜𝑡𝑜𝑟,𝐹𝑢𝑙𝑙 𝐿𝑜𝑎𝑑 × (𝑉𝐹𝐷 𝑆𝑝𝑒𝑒𝑑 𝐹𝑟𝑎𝑐𝑡𝑖𝑜𝑛)𝑘

𝜂𝑉𝐹𝐷

Where, kWMotor, Full Load = measured input power. VFD Speed Fraction = fraction of full speed. k = VFD affinity exponent, assumed to be 2.5. 𝜂VFD = VFD efficiency

The assumed air flow profile is shown in the Table 14 below.

Table 14: Airflow profile used in proposed case calculations


Minimum VFD speed of 50% corresponding to minimum ventilation air flow 50% of design.

VFD affinity exponent of 2.5

Mon Tue Wed Thu Fri Sat Sun

12am-1am 1 50% 50% 50% 50% 50% 50% 50%

1am-2am 2 50% 50% 50% 50% 50% 50% 50%

2am-3am 3 50% 50% 50% 50% 50% 50% 50%

3am-4am 4 50% 50% 50% 50% 50% 50% 50%

4am-5am 5 50% 50% 50% 50% 50% 50% 50%

5am-6am 6 75% 75% 75% 75% 75% 50% 50%

6am-7am 7 100% 100% 100% 100% 100% 50% 50%

7am-8am 8 100% 100% 100% 100% 100% 50% 50%

8am-9am 9 100% 100% 100% 100% 100% 50% 50%

9am-10am 10 100% 100% 100% 100% 100% 50% 50%

10am-11am 11 100% 100% 100% 100% 100% 50% 50%

11am-12pm 12 100% 100% 100% 100% 100% 50% 50%

12pm-1pm 13 75% 75% 75% 75% 75% 50% 50%

1pm-2pm 14 100% 100% 100% 100% 100% 50% 50%

2pm-3pm 15 100% 100% 100% 100% 100% 50% 50%

3pm-4pm 16 75% 75% 75% 75% 75% 50% 50%

4pm-5pm 17 75% 75% 75% 75% 75% 50% 50%

5pm-6pm 18 50% 50% 50% 50% 50% 50% 50%

6pm-7pm 19 50% 50% 50% 50% 50% 50% 50%

7pm-8pm 20 50% 50% 50% 50% 50% 50% 50%

8pm-9pm 21 50% 50% 50% 50% 50% 50% 50%

9pm-10pm 22 50% 50% 50% 50% 50% 50% 50%

10pm-11pm 23 50% 50% 50% 50% 50% 50% 50%

11pm-12am 24 50% 50% 50% 50% 50% 50% 50%

Hour of Day


Limited weekend and overnight activity in loading dock.

SF-1 & EF-36 VFDs are ramped in unison.


COST ESTIMATE




(978) 208 - 0609

Total


1 3 CO sensors ea 4 $750 $3,000 $150 1 8 $4,800 $7,800

2 3 SF-1, 30HP Motor & VFD ea 1 $7,553 $7,553 $150 1 4 $600 $8,153

3 3 EF-36, 40HP Motor & VFD ea 1 $9,263 $9,263 $150 1 2 $300 $9,563

4 3 VFD BAS Points & Programming ea 6 $1,500 $9,000 $150 1 4 $3,600 $12,600

5 3 As-Builts ea 1 $0 $150 1 4 $600 $600

6 3 Contractor Commissioning Labor ea 2 $0 $150 1 4 $1,200 $1,200

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $39,915

1 Means







Total $74,315

Sources

Opinion of Probable Construction CostECM 09.00 (f)-1: Loading Dock Variable Exhaust Controls



ECM 9.00 (F)-2 REDUCE LAB AIR CHANGES

MEASURE ECONOMICS SUMMARY ECM # 09.00 (f)-2 Reduce Lab Air Changes


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


1,108,663 $110,866 505,892 $60,707 7,047 $70,471 $242,044 $807,463 3.3

BASE CASE All the labs in the building are designed as once-through ventilation systems. Supply air is provided to the labs by dual-duct air handlers with VFDs and static pressure control. The conditioned hot and cold air is supplied to the labs by constant volume dual-duct mixing boxes and is exhausted by a combination of general lab exhaust in addition to the lab fume hood exhaust. Most of the existing fume hoods exhaust systems are original to the building and constant volume by-pass type hood design. There are approximately 33 exhaust fans for lab exhaust. Seventeen of the fans have variable frequency drives with static pressure controls and the remainder are fixed speed. Based on our investigation of existing air flows and lab sizes, the labs currently operate at approximately 7 air changes/hour (ACH) on average throughout the facility. UMass engineering staff indicated that when lab spaces are renovated they design for 6 ACH and they estimate the original lab design was 8 – 10 ACH. Some AC units serving labs are scheduled off at night, however the air change remains constant whenever the AC units serving the respective labs are operating. For comparison purposes, minimum air change rates in the new LRB building are currently set to approximately 4.5 ACH.

Table 15: Lab square footage and airflow data

PROPOSED CASE The proposed case is to install VFDs on the existing constant volume exhaust fans and rebalance labs to 5 ACH. 5 ACH was chosen as a conservative estimate based on the LRB’s current minimum average air change rate of 4.5 ACH. Also, new duct static pressure sensors would be installed in the exhaust ducts and control exhaust fans to maintain a duct static set-

Lab Gross Square Footage 326,807 ft2 From UMMS SF Breakdown

Interior Walls, Mechanical, etc. 5% Assumed

Net Square Footage 310,467 ft2

Avg Room Height 12 ft Fls 1-2 have 15' ceiling, upper fls are 9'

Total Volume 3,725,600 ft3

Total Measured Exhaust Air 435,819 ft3/min From RGV Air Flow Study

Total Measured Exhaust Air 26,149,140 ft3/hr From RGV Air Flow Study

air changes/min 0.12

air changes/hr 7.02 ACH


point, which would be set by the balancer to meet the proposed air change rates. Each lab will have the constant volume supply air boxes and exhaust ducts rebalanced to meet the 5 ACH. During the design phase, individual labs will be evaluated for the appropriate flow reduction, such labs with hazardous chemicals, which may not be reduced. Lab fume hoods flows should also be checked to ensure proper airflows are maintained. A reduction in air flow at the box level will result in the supply air handler fan VFD ramping down based on the duct static pressure control. This measure also involves installing new premium efficiency motors on 15 exhaust fans that are not currently equipped with VFDs.

ENERGY SAVINGS METHODOLOGY A ‘Global Parameter’ in eQuest was used to assign an ACH rate for the lab areas. The Global Parameter, ‘Lab ACH’, was assigned at the zonal level for all labs except for animal quarters and specialized containment areas. The ACH Global Parameter was parametrically changed from 7 (base case) to 5 (proposed case). Also, the system airflow for the AC units serving lab areas was adjusted to account for the air change reduction.


COST ESTIMATE




(978) 208 - 0609

Total


1 5HP Motor & VFD ea 5 $3,953 $19,763 $150 2 6 $9,000 $28,763

2 7.5HP Motor & VFD ea 4 $4,283 $17,130 $150 2 6 $7,200 $24,330

3 10HP Motor & VFD ea 2 $4,568 $9,135 $150 2 8 $4,800 $13,935

4 15HP Motor & VFD ea 3 $5,333 $15,998 $150 2 8 $7,200 $23,198

5 25HP Motor & VFD ea 1 $6,885 $6,885 $150 2 10 $3,000 $9,885

6 30HP Motor & VFD ea 1 $7,553 $7,553 $150 2 10 $3,000 $10,553

7 BAS programming ea 16 $0 $150 1 8 $19,200 $19,200

8 Testing and Balancing ea 126 $0 $150 2 8 $302,400 $302,400

9 As-Builts ea 1 $0 $150 1 24 $3,600 $3,600

10 Contractor Commissioning Labor ea 16 $0 $150 1 4 $9,600 $9,600

11 BAS Points for VFDs ea 48 $1,500 $72,000 $150 1 0 $0 $72,000

Subtotal $517,463

1 Means




Notes 8 Floors 5-7 = 90 labs and Floors 2-4 = 36 labs Commissioning 5% $31,100



Total $807,463


ECM 09.00 (f)-2: Reduce Lab Air Changes


Sources


ECM 9.00 (F)-3 INSTALL VFDS & CO2 VENTILATION CONTROLS ON

LIBRARY AC UNITS

MEASURE ECONOMICS SUMMARY ECM # 09.00 (f)-3 Install VFDs & CO2 Ventilation Controls on Library ACs


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


300,790 $30,079 70,026 $8,403 2,172 $21,721 $60,203 $139,565 2.3

BASE CASE The four air handling units serving the library, AC-22, 23, 24, and 25, are all constant volume and do not have VFDs. Table 16 below shows equipment information on these units.

Table 16: Library Air Handler Equipment Information

Unit Service

Design Airflow Data

Supply Fan Data

Return Fan Data

Schedules: Equipment &/or Occupancy

Total Supply Airflow

Minimum Outdoor Airflow

Motor Namplate

Motor Namplate

cfm cfm hp hp

AC-22 Library 14,035 2,800 20 20 6:30-23:45 Mon-Thu/6:30-

21:15 Fri

AC-23 Library 11,185 2,240 15 15 6:32-23:47 Mon-Thu/6:32-

23:17 Fri

AC-24 Library 18,665 7,350 20 7.5 6:34-23:49 Mon-Thu/6:34-

23:19 Fri

AC-25 Library 17,845 5,530 20 7.5 6:36-23:45 Mon-Thu/6:36-

23:15 Fri

These units generally provide either a fixed quantity of minimum outdoor/ventilation air (%OA) to the library, or provide 100% outside air when enabled to do so by either a single point or comparative drybulb economizer sequence. Slight variation in economizer cutoff is observed between library units, however operation seems to be independent of time-of-day or space occupancy. The economizer operation of typical units is shown in Figure 108 and Figure 109 below.


Figure 108: This trend screenshot below for AC-25, which runs 24/7, shows an example of a single point economizer cutoff. When the outdoor temperature is below 68, the economizer is enabled and the mixing air dampers are set for 100% outside air. When the ambient temperature rises above 68°F, economizer is disabled and the mixing dampers go to their minimum %OA position. Also note that in this screenshot the unit only operates with the mixing air dampers at 100% OA or minimum %OA.


Figure 109: This trend screenshot below for AC-22, which runs during the shaded periods in the screenshot, shows an example of a comparative dry bulb economizer cutoff. When the outdoor temperature more than approximately 6 degrees below the return air temperature, the economizer is enabled and the mixing air dampers are set for 100% outside air. When the ambient temperature rises above this point, economizer is disabled and the mixing dampers go to their minimum %OA position. Also note that in this screenshot the unit only operates with the mixing air dampers at 100% OA or minimum %OA.


In addition, it was observed based on temperature sensor readings that AC-22 & 24 were fully recirculating and taking in no ventilation air when commanded to take in the minimum air percentage, indicating a potential issue with the mixing dampers or actuators on these units. It was also observed that either mixed or return air temperature sensors on one or more units.

PROPOSED CASE In the proposed case of this measure, VFDs are installed on the supply and return fans, CO2 sensors are installed in the return ducts, and any non-functional dampers and actuators are repaired or replaced on each library AC unit. In addition, a sequence is implemented whereby the outside air dampers are modulated to maintain the return CO2 below a set-point (typically 800 – 1,000 ppm), and the supply fan VFD maintaining a default minimum speed set-point of 80%, ramping up as the return temp rises above 76oF (adj.).

ENERGY SAVINGS METHODOLOGY This measure will result in fan energy savings during low load periods when the fan speed is allowed to ramp down, and will also result in heating and cooling savings during unoccupied periods due to the reduced loads associated with the ventilation air.

The energy savings for this measure were calculated by parametrically changing the AC units serving the library to variable flow with a minimum of 85%. This will allow the air flow to modulate based on the needs of the space. The parametric changes that were made in the eQuest model include changing the units FAN-CONTROL to SPEED, and changing the MIN-FLOW-RATIO to a value 0.85. Additionally, the min-OA was parametrically changed to CO2 control.


COST ESTIMATE The following estimate was developed using estimates for materials, labor, and programming costs. Contingency, engineering, construction administration, commissioning expense estimates are also included where applicable. This measure also includes a cost allocation to repair or replace non-functional mixing air dampers & actuators, along with any inaccurate or non-functioning return or mixed air temperature sensors in the library units.





(978) 208 - 0609

Total


1 2 15 HP motor ea 2 $1,800 $3,600 $150 1 8 $2,400 $6,000

2 2 20 HP motor ea 4 $2,200 $8,800 $150 1 8 $4,800 $13,600

3 3 VFD (15HP) ea 2 $500 $1,000 $150 1 8 $2,400 $3,400

4 3 VFD (20HP) ea 4 $350 $1,400 $150 1 8 $4,800 $6,200

5 3 CO2 Sensors in return air ea 4 $1,000 $4,000 $150 1 4 $2,400 $6,400

6 3 Replace OA Dampers ea 2 $1,000 $2,000 $150 2 12 $7,200 $9,200

7 3 VFD (7.5HP) ea 2 $3,383 $6,765 $150 1 8 $2,400 $9,165

8 2 7.5 HP Motor ea 2 $900 $1,800 $150 1 8 $2,400 $4,200

9 3 As-Builts ea 4 $0 $150 1 4 $2,400 $2,400


11 3 VFD BAS Points & Programming ea 8 $1,500 $12,000 $150 $0 $12,000

Subtotal $77,365

1 Means




Notes 1 Line 11 include programing in Material Cost Commissioning 15% $14,000



Total $139,565

Sources

Opinion of Probable Construction CostECM 09.00 (f)-3: Install VFDs & CO2 Ventilation Controls on Library AHUs



ECM 17.09 (F) RECLAIM RETURN AIR ON AC-12

MEASURE ECONOMICS SUMMARY ECM # 17.09 (f) Reclaim Return Air on AC-12


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


8,483 $848 0 $0 659 $6,594 $7,442 $39,600 5.3

BASE CASE Training rooms in 2nd floor Basic are 100% variable exhaust designed for 2,000 CFM, with no return from the space. This space was repositioned from lab space to training area in the last few years. The space relief remained 100% exhaust because there was no additional capacity in the return air ducts. An ongoing renovation on the 1st floor directly beneath the training rooms is changing the return air for the 1st floor space from AC-12 to AC-30, and the return air duct to AC-12 was capped, reducing the return airflow delivered to AC-12.

Table 17: AC-12 design information

Supply Air Flow CFM

Return Air

CFM

Minimum OA Flow

CFM Minimum

%OA

AC-12 23,022 18,492 4,530 20%

PROPOSED CASE This measure’s proposed case is to convert exhaust to return by installing ductwork to connect the training room ceiling plenum to AC-12’s return air duct. The AC-12 return air riser is located in a nearby duct chase, and the ductwork will penetrate the chase wall to connect with the AC-12 return. This will utilize the recent capacity gain in AC-12 return resulting from 1st floor space renovation. As part of this measure we propose balancing air flows to return approximately 2,000 CFM to AC-12, and cap exhaust duct or modulate dampers fully closed.

ENERGY SAVINGS METHODOLOGY The energy savings from this measure were calculated by changing the AC-12’s percent outside air to account for the increase in return air. The parametric change made in eQuest was decreasing the MIN-OUTSIDE-AIR value from 0.74 (base case) to 0.6768 (proposed Case).


COST ESTIMATE




(978) 208 - 0609

Total


1 3 Ductwork modifications ea 1 $5,000 $5,000 $150 2 24 $7,200 $12,200


3 3 Programming ea 1 $0 $150 1 24 $3,600 $3,600

4 4 General Construction ea 1 $1,000 $1,000 $150 2 16 $4,800 $5,800

5 3 As-Builts ea 1 $0 $150 1 8 $1,200 $1,200


7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $26,400

1 Means




Notes 1 Commissioning 10% $3,000

2 Construction Observation 5% $1,500


Total $39,600


Sources

Opinion of Probable Construction CostECM 17.09 (f): Reclaim Return Air on AC-12


ECM 18.00 (F)-1 OPTIMIZE PERIMETER HW RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-1 Optimize Perimeter HW Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


0 $0 0 $0 387 $3,874 $3,874 $31,000 8.0

BASE CASE The perimeter HW system serving radiators throughout the school building is separated into three zones – north, east, and west. The south zone is disconnected. The system turns on below when the outside air temperature is 38oF or below. The system has a temperature reset based on outside air temperature and is believed to reset from 180 oF down to 160 oF before turning off. There are no automatic zone valves and the HW pumps provide a constant flow whenever the system is on.

Table 18: Existing Perimeter HW Reset Schedule

Base Case Perimeter HW System

Outside Air Temp

°F

HW Supply Temp

°F

0 180 38 160

PROPOSED CASE This measure is to optimize the existing HW temperature reset by introducing a primary/secondary reset schedule, reducing the low limit supply temperature to 120 oF. A new secondary reset will reset the supply set-point above the outdoor air temperature-based value if necessary based on load to the spaces. The space load in the secondary reset will be indicated by supply – return differential temperature.


Table 19: Proposed Perimeter HW Reset Schedule

Proposed Case Perimeter HW System

Outside Air Temp

°F

HW Supply Temp

°F

0 180 38 120

ENERGY SAVINGS METHODOLOGY A customized bin-based excel spreadsheet was created to model the energy savings. TMY3 data for Worcester, MA was sorted into hourly 5oF temperature bins and imported into the model. The formula shown below was used to calculate the heat loss from the cylindrical pipe for each bin:

𝑄𝐻𝑒𝑎𝑡 𝐿𝑜𝑠𝑠 = 2 𝜋 𝑘 (𝑡𝑖 − 𝑡𝑜)

ln (𝑟𝑜

𝑟𝑖)

Where,

QHeat loss = heat loss through pipe wall per foot of pipe, including insulation (Btu/hr-ft)

k = Conductivity of insulation material (Btu/hr-ft-oF)

ti = Temperature of interior surface of insulation, exterior pipe surface (oF); Assumed equal to HW supply temperature

to = Ambient air temperature (oF)

ro = Outside radius of cylinder, pipe radius plus thickness of insulation material (ft)

ri = Inside radius of cylinder, equal to pipe radius (ft)

ln = Natural logarithm

This formula was used in both the base and proposed cases, and the HW supply temperature is varied in each bin according to the reset schedules shown above. The difference in heat loss between the base and proposed case in each temperature bin is multiplied by the hours in each bin and by the total estimated pipe length, and divided by the steam-HW converter efficiency.


HW loop is operating for all hours when the outside dry-bulb temperature is below 38°F.

Average pipe outside diameter is estimated to be 2.5” based on visual observation


Pipe insulation thickness is estimated to be 1.5” based on visual observation

Ambient temperature was assumed to be 70oF based on average space temperatures and that the building thermal mass maintained that temperature consistently

Insulation conductivity was assumed to be 0.023 Btu/hr-ft-oF (www.engineeringtoolbox.com)

Total piping length was estimated to be 22,512 ft. This estimate is calculated assuming the piping follows the west, east, and north perimeter of the building on each floor, multiplied by 2 to account for supply and return piping.

HW converter efficiency is assumed to be 96%.






(978) 208 - 0609

Total


1 3 Programming ea 3 $0 $150 1 24 $10,800 $10,800

2 3 Return water temperature sensors ea 3 $500 $1,500 $150 1 8 $3,600 $5,100

3 3 As-built ea 1 $0 $150 1 12 $1,800 $1,800


5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $20,400

1 Means







Total $31,000

Opinion of Probable Construction CostECM 18.00 (f)-1: Optimize Perimeter HW Reset


Sources


ECM 18.00 (F)-2 AUDITORIUM SCHEDULING & OCCUPANCY CONTROLS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-2 Auditorium Scheduling & Occupancy Controls


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


249,081 $24,908 32,778 $3,933 1,234 $12,341 $41,182 $202,950 4.9

BASE CASE There are three auditoriums stacked on top of each other that are served by AC-1. These auditoriums have dual-duct VAV mixing boxes that are pneumatically controlled and do not have any setbacks. Occupancy in these auditoriums is highly variable; it is typically heavy during the school year but changes often and unpredictably based on class & lecture schedules. The auditoriums are also regularly used at nights and on weekends for various events. Table 20 below shows the VAV box airflow serving each auditorium.

Table 20: Summary of Auditorium VAV Boxes

AC-1 operates 24/7 to provide dual-duct supply air to the auditoriums. Table 21 below shows equipment data for AC-1.

Table 21: AC-1 Equipment Data

Supply Air Flow

CFM

Minimum OA Flow

CFM

Minimum %OA

Motor HP

Motor kW

AC-1 23,022 4,530 20% 50 39.3

Auditorium 1 - Level 2-3 Auditorium 2 - Level 4-5 Auditorium 3 - Level 6-7

Box Name CFM Box Name CFM Box Name CFM

MB01* 3-26 345 MB01* 5-26 345 MB01* 7-26 345

MB01* 3-27 330 MB01* 5-27 330 MB01* 7-27 330

MB01* 3-28 1,995 MB01* 5-28 1,995 MB01* 7-28 1,995

MB01* 3-29 975 MB01* 5-29 975 MB01* 7-29 975

MB01* 3-30 330 MB01* 5-30 330 MB01* 7-30 330

MB01* 3-31 2,550 MB01* 5-31 2,350 MB01* 7-31 2,860

MB01* 3-32 345 MB01* 5-32 345 MB01* 7-32 345

MB01* 3-33 1,760 MB01* 5-33 1,760 Total CFM 7,180

Total CFM 8,630 Total CFM 8,430


PROPOSED CASE This measure’s proposed case is to upgrade controls in the auditorium systems to operate AC-1 & VAV mixing boxes according to actual occupancy needs in each of the auditoriums. This will be done by a mix of advanced programming and using both occupancy sensor and CO2 sensor feedback to optimize energy consumption.

The proposed case also includes the retrofitting dual-duct mixing boxes in the auditoriums with electronic actuators or transducers to control the existing pneumatic actuators and discharge air temperature sensors. Space temperature sensors and occupancy sensors would be installed in each of the auditoriums and CO2 sensors would be installed in the return air duct. A daily equipment schedule would be programmed in the BAS for AC-1 to operate from 6:00am – 10:00pm, 7 days. When no occupants are sensed for 15 minutes (adj.), allow the VAV mixing boxes to go into an unoccupied daytime mode. During unoccupied daytime mode, the VAV box dampers would modulate to minimum position unless the space temperature exceeds a light setback of temperature set-point +/- 4oF (adj.). The outside air dampers would modulate to maintain CO2 levels are below set-point sensed by the return air CO2 sensor. When CO2 levels are below a low set-point and occupancy sensors indicate there are no people in the space for 2 hours (adj), then the auditorium will go into deep setback mode. During deep setback mode, the VAV boxes would modulate to minimum position unless the space temperature exceeds asetback of temperature set-point +/- 8oF (adj.) If all auditoriums are in deep setback mode, shut off AC-1 until the next scheduled start time, or until an occupancy sensor is triggered for more than 5 min (adj.), bringing any auditorium out of deep setback. Keep AC-1 programming & sequences except for the scheduling and deep setback on/off control described above.

Note: Given the effort required to access the VAV mixing boxes UMass may want to consider replacing the boxes or retrofitting new box dampers when the ceiling is open. A high-level estimate would include at least $2,500 - $5,000 per mixing box in addition to the cost of the base retrofit scope for a complete replacement.

ENERGY SAVINGS METHODOLOGY The savings for this measure were calculated by parametrically changing the equipment and space schedules in eQuest. Table 22 below shows the proposed case fan schedule, ‘sFan AN AC-1’, that was created to mirror the occupied schedule. The fans will cycle on during occupied periods, and during unoccupied periods the fan will cycle off.

Table 22: Auditorium Occupancy Schedule Used in eQuest model

AC-1 Proposed schedule

6:00am-6:00pm, Mon, Wed, Fri

6:00am-9:00p Tue, Thu

4:00pm-9:00pm, Sat

eQuest Fan Schedule


The outside air parameter was also changed to model the CO2 OA control. It was assumed that there was low occupancy during the following periods, Monday – Friday: 6:00am – 8:00am, 12:00pm – 1:00pm, 5:00pm – 6:00pm.

Note: The control upgrades necessary to implement this measure will also inherently implement similar capabilities and functionality as in “ECM 4.07 (f) Upgrade Terminal VAV Mixing Box Controls.” These savings from the DDC upgrade are included in this measure.


COST ESTIMATE




(978) 208 - 0609

Total


1 3 Actuator (2 per mixing box) ea 46 $250 $11,500 $150 1 1 $6,900 $18,400

2 3 DDC VAV box controller (note 1) ea 23 $500 $11,500 $150 1 2 $6,900 $18,400

3 3 Space Temperature ea 23 $100 $2,300 $150 1 2 $6,900 $9,200

4 4 BAS Points & Programming VAV Boxes ea 23 $500 $11,500 $150 1 2 $6,900 $18,400

5 3 Ceiling Occupancy Sensors ea 9 $150 $1,350 $150 1 4 $5,400 $6,750

6 3 CO2 Sensors ea 9 $500 $4,500 $150 1 4 $5,400 $9,900

7 3 BAS Programming - AC Unit ea 3 $0 $150 1 4 $1,800 $1,800

8 3 As-Builts ea 1 $0 $150 1 32 $4,800 $4,800


10 3 Lift ea 3 $2,500 $7,500 $150 0 0 $0 $7,500

Subtotal $108,950

1 Means




Notes 1 DDC controller to have 2 DO for dampers, 1 DA, 1 Space temp Commissioning 20% $26,200



Total $202,950

Materials Labor

Sources

Opinion of Probable Construction CostECM 18.00 (f)-2: Auditorium Scheduling & Occupancy Controls

General


ECM 18.00 (F)-3 REPLACE HEATING VALVES & ACTUATORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-3 Repair Heating Valves & Actuators


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


0 $0 220,569 $26,468 5,274 $52,737 $79,206 $59,050 0.7

BASE CASE Historical trend logs show that on select dual-duct AC units in the school building, a significant temperature rise occurs across either the preheat or hot deck coil with the unit running and the valve commanded fully closed. On one particular AC unit, a temperature rise such as this was observed across both the preheat and hot deck coils. This may be due to leaking valves or insufficient pressure at the pneumatic actuator to hold the valve closed.

See Figure 110 and Figure 111 for trend screenshots that illustrate the air temperature rise observed across a typical AHU preheat and hot deck coil when the unit is running.

Table 23 below lists the specific AHUs included in this measure and the corresponding average temperature rise across the preheat and hot deck coils observed in trend data.

Table 23: List of Units Involved in Heating Leakby Measure

AHU # Preheat

Temperature Rise Hot Deck

Temperature Rise

AC-4 0°F 38°F

AC-7 0°F 6°F

AC-8 0°F 23°F

AC-9 0°F 7°F

AC-13 0°F 10°F

AC-14 8°F 20°F

AC-16 0°F 15°F

AC-25 0°F 11°F

AC-31 11°F 0°F

PROPOSED CASE For each of the AHUs listed in the table above, we recommend replacement of the preheat or hot deck heating coil valve with a new valve body and replacement of the existing pneumatic actuator to eliminate the hot water or steam leakage observed.


ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in heating energy used during periods when the heating demand is less than the amount that results from valve leakage. In cases of a preheat leak-by, chilled water savings result from the additional mechanical cooling needed to meet discharge set-points after supply air is preheated more than necessary.

The energy savings associated with this measure were estimated using a bin spreadsheet model that calculates the sensible heat gain across each AC unit’s preheat and hot deck coil based on trend data observations.

The average temperature rise across each coil was estimated using trends of mixed or outdoor air, preheat leaving air, and hot deck temperature during periods when the unit was running but the corresponding heating valve was closed. The table in the base case description for this measure above shows the average temperature rise across the preheat and hot deck coils used in energy savings calculations.

Energy savings were then calculated and extrapolated using TMY3 weather data for Worcester, MA. For each AC, if the binned outdoor air temperature was greater than the point at which heating was required, wasted heating energy was calculated using the following equation:

𝑄 [𝐵𝑡𝑢


Where ‘Supply Airflow’ is equal to each AC’s total supply airflow documented in design drawings. Heating energy savings (Btu) were summed across all ACs for the entire year and divided by a steam heating value of 1,000 Btu/lb to calculate the measure’s annual steam savings (Mlbs).


Figure 110: This trends screenshot for AC-14 below shows the large difference between preheat leaving air temperature (BLUE) and outdoor air temperature (RED) when the preheat control valve (ORANGE) is closed. The constant volume 100% OA unit is running continuously throughout the period shown in this screenshot.


Figure 111: This trend screenshot for AC-14 below shows the large difference between the hot deck leaving air temperature (RED) and preheat leaving air temperature (ORANGE) when the preheat control valve (BLUE) is closed. The constant volume 100% OA unit is running continuously throughout the period shown in this screenshot.






(978) 208 - 0609

Total


1 3 New 3" Valve ea 10 $1,800 $18,000 $150 2 6 $18,000 $36,000

2 3 As-Builts ea 1 $0 $150 1 1 $150 $150


4

5

6

7

8

9

10

Subtotal $39,150

1 Means




Notes 1 Assume new valve Commissioning 5% $2,400



Total $59,050

Opinion of Probable Construction CostECM 18.00 (f)-3: Repair Heating Valves & Actuators


Sources


ECM 18.00 (F)-4 REPLACE COOLING VALVES & ACTUATORS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-4 Repair Cooling Valves & Actuators


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


0 $0 74,420 $8,930 173 $1,725 $10,656 $18,250 1.7

BASE CASE Historical trend logs show that on select dual-duct AC units in the school building, a significant temperature drop occurs across either the cold deck coil with the unit running and the cooling valve commanded fully closed. This may be due to leaking valves or insufficient pressure at the pneumatic actuator to hold the valve closed.

See Figure 112 for a trend screenshot that illustrates the air temperature drop observed across an AC unit cooling coil when the unit is running.

Table 24 below lists the specific ACs included in this measure and the corresponding average temperature drop across the cooling coils observed in trend data.

Table 24: List of Units Involved in Heating Leakby Measure

AHU # Cooling

Temperature Drop

AC-7 14°F

AC-8 5°F

AC-40 13°F

PROPOSED CASE For each of the AHUs listed in the table above, we recommend replacement of the cold deck coil valve with a new valve body and replacement of the existing pneumatic actuator to eliminate the chilled water leakage observed.

ENERGY SAVINGS METHODOLOGY Energy savings are derived from the reduction in cooling energy used during periods when the cooling demand is less than the amount that results from valve leakage.

The energy savings associated with this measure were estimated using a bin spreadsheet model that calculates the sensible cooling load across each AC’s cold deck coil based on trend data observations.


The average temperature drop across each coil was first estimated using trends of mixed air, preheat coil leaving air, and cold deck temperature during periods when the unit was running but the cooling valve was closed. The table in the base case description for this measure above shows the average temperature rise across the cold deck coils used in energy savings calculations.

Energy savings were then calculated using TMY3 weather data for Worcester, MA. For each AC unit, if the binned outdoor air temperature was lower than the point at which cooling was required, wasted cooling energy was calculated using the following equation:

𝑄 [𝐵𝑡𝑢


Where ‘Supply Airflow’ is equal to each AC’s total supply airflow documented in design drawings. Cooling energy savings (Btu) were summed across all AHUs for the entire year and converted to chilled water energy usage to calculate the measure’s annual steam savings (Ton-hrs).


Figure 112: This trend screenshot for AC-7 below shows the large difference between the mixed air temperature (RED) and cold deck temperature (BLUE) when the cold deck valve (PINK) is closed (note that the unit has no preheat coil). The unit is running continuously throughout the period shown in this screenshot.






(978) 208 - 0609

Total


1 3 New 3" Valve ea 3 $1,800 $5,400 $150 2 6 $5,400 $10,800

2 3 As-Builts ea 1 $0 $150 1 1 $150 $150

3 3 Contractor Commissioning Labor ea 3 $0 $150 1 2 $900 $900

4

5

6

7

8

9

10

Subtotal $11,850

1 Means




Notes Commissioning 5% $800



Total $18,250

Opinion of Probable Construction CostECM 18.00 (f)-4: Repair Cooling Valves & Actuators

Sources



ECM 18.00 (F)-5 REPAIR ECONOMIZER DAMPERS & OPTIMIZE SEQUENCE

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-5 Repair Economizer Dampers & Optimize Sequence


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


61,505 $6,151 639,057 $76,687 7,186 $71,862 $154,700 $259,900 1.7

BASE CASE Among the AC units in the school building which have return air, a number of issues were observed with the mixing air operations. A comprehensive summary of the issues involved in this measure are shown in Table 25 below. It is unclear if the economizer issues described are due to programming logic, mechanical issues/failures, or both. Note that this measure excludes the four library AHUs, as their mixing air operation is addressed in ECM 9.00 (f)-3 Install VFDs & CO2 Ventilation Controls on Library AC Units.

It was also observed that the written sequences for the clip on AC units have a comparative enthalpy economizer sequence based on AC-39 return air %RH, however a review of ALC logic pages indicate that the economizer sequence in place is dry-bulb based with OA-enable set-points of 60oF for the lobby AC-37 & 70oF for ACs 38, 39, & 40.


Table 25: Economizer sequence characteristics of AC units

Unit

Economizer OAT

Enable Setpoint

from ALC Logic

(deg F)

CDT/DAT

Setpoint from

ALC Logic

(deg F)

Observed IssueEffect on

Unit

Date

Range of

Issue

Trend Data Damper Control Signal Observations

AC-1 70 48-53 MAD - Stuck 100%

Open

Over-

economizing

July - Oct

2014

MAD is remains at 30% when OAT < 70F, but

damper must be stuck open because MAT always

is equal to OAT.

AC-2 70 55-60 Economzier

Sequence

Under-

economizing

April

2014

MAD signal varies from 20 - 30%, and does not

control to CDT setpoint. MAT is consistently

greater (5-10F) than CDSPT.


Sequence

Under-

economizing

April

2014





Sequence

Under-

economizing

April

2014




AC-6 70 55-60 MAD - Stuck 10%

Open

Under-

economizing

Sept -

Oct 2014

MAD opens 100% when OAT < 70F, but damper

must be stuck closed because MAT never falls

below RAT

AC-7 70 55-60

Economzier

Sequence

Manual Overrides

Under-

economizing

Sept

2014

MAD only 10% open when OAT < 57F. Suggest

checking manual overrides.

AC-8 70 55-60 N/A N/A N/A MAD signal controls well to MAT set point of 60F.

AC-9 70 55-60 MAD - Stuck 100%

Open

Over-

economizing

Sept

2014

MAD 30% open when OAT > 70F, but damper must

be stuck open because MAT always is equal to

OAT

AC-10 70 55-60 N/A N/A N/A

Cannot determine performance from trend data

due to failed or miscalibrated MAT sensor.

Suggest replacing sensor and conducting field

testing.

AC-11 70 55-60 N/A N/A N/ACannot determine performance from trend data

due to lack of RAT. Suggest field testing.

AC-12 70 55-60 N/A N/A N/A MAD signal controls well to MAT set point of 58F.


Sequence

Under-

economizing

Sept

2014





Sequence

Under-

economizing

Sept

2014




AC-16 70 55-57 N/A N/A N/A MAD signal controls well to CDT set point.




AC-37 60 55-95 MAD - Stuck 100%

Open

Over-

economizing

Sept

2014

Trends indicate the damper economizer

sequence is not operating in accordance with the

ALC Logic page or written sequence. Suggest

functional testing.


Sequence

Under-

economizing

Sept

2014

MAD remains at 10% when OAT < 70F. MAT is

consistently greater (5-15F) than CDSPT.

AC-39 70 55-65

Economzier

Sequence

MAD Cannot Open

Under-

economizing

Sept

2014

MAD remains at 35% when OAT < 70F, but damper

must be stuck closed because MAT always is

equal to RAT


Sequence

Under-

economizing

Sept

2014

MAD remains at 0% when OAT < 70F. This issue

may be caused by valve leakby. Suggest

functional testing after valve leakby is repaired.


Figure 113: This trend screenshot for AC-9 below shows a mixed air damper that is stuck and fully bringing in outside air. Note that despite the mixed air damper command being switched between the fully open and minimum outdoor air positions, the mixed and outside air temperatures remain essentially equal. The slight difference between the ambient and mixed air temp seen throughout the screenshot period is likely due to sensor error. The unit is running continuously throughout the period shown in this screenshot.


PROPOSED CASE This measure is to repair the mixing air dampers on units listed as having operational issues in Table 25. This includes the repair or replacement of non-functional outside air, mixed air, and return air dampers & actuators, repair to any damaged air lines to pneumatic operators, and the replacement of any failed signal air receivers, digital-pneumatic transducers, or other control devices. This measure also involves changes being made to the economizer sequence so that the mixing dampers on all applicable units modulate to maintain the cold deck temperature set-point for all dual-duct AC units.

ENERGY SAVINGS METHODOLOGY The energy savings for this measure were modeled parametrically in eQuest. The system over-economizing and added load on the cold deck cooling coil is modeled by setting the base case preheat temperature parameter to 68 oF. This value was arrived at during the calibration process. The proposed case preheat temperature was modeled as 65oF. This value was chosen to avoid overestimating energy savings due to the steam consumption of the dual duct systems while in cooling operation that results from the heating minimum flow of 30% year-round.


COST ESTIMATE




(978) 208 - 0609

Total


1 3 Damper Repair ea 8 $500 $4,000 $150 2 8 $19,200 $23,200

2 3 New electric actuator ea 8 $750 $6,000 $150 1 8 $9,600 $15,600


4 3 New Damper allocation ea 8 $3,500 $28,000 $150 2 16 $38,400 $66,400

5 3 Testing & Balancing ea 16 $0 $150 2 4 $19,200 $19,200

6 3 As-Builts ea 1 $0 $150 1 4 $600 $600


8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $144,200

1 Means




Notes 1 ECM for 16 AHU's Commissioning 15% $26,000



Total $259,900

Opinion of Probable Construction CostECM 18.00 (f)-5: Repair Economizer Dampers & Optimize Sequence


Sources


ECM 18.00 (F)-6 AIR-SEALING REPAIRS ON AC UNITS

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-6 Air Sealing Repairs on AC Units


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


276,499 $27,650 20,259 $2,431 -777 -$7,771 $22,310 $442,100 19.8

BASE CASE The supply air handlers are original to the building (1971). Although they continue to provide adequate conditioned air, the air handlers’ sheet metal boxes have significant corrosion problems caused by chilled water coil condensate. Most of the air handlers lose a notable volume of air through gaps in the lower perimeter of the box where the cooling coil is located. There were also numerous air leaks noted on the supply air ductwork sheet metal seams where the sealant has deteriorated or the seams have just started to slightly pull apart. This air is lost to the 8th floor mechanical space. The air losses around the bottom perimeter of the air handler boxes is so severe that it blows the condensate water out of the drip pans which run around the perimeter of the cooling coil box. Some of the drip pans have been filled with stainless steel wool to prevent the condensate water from being blown around the mechanical room floor (as can be seen in the picture on the following page).


Figure 114: Example of AC unit drip pan condition

PROPOSED CASE Eliminate leakage areas by refurbishing the air handlers. This will be done with a rapid-cure polymer composite coating on the interior of the cold deck. The coating is customized to each air handler during installation, and it will fill in the cracks and seal the sections with air leaks and pitch the drain pan to eliminate standing water. The composite polymer is comprised of a first layer of epoxy that bonds to the metal, a second layer fire-barrier of NFPA-compliant material, and finally an anti-microbial, waterproof topcoat. The air handler is completely isolated during the process by sealing the adjacent duct work and by employing negative air machines. It can be installed in place without the removal of condensate pans. This composite sealant is fully compliant with NFPA, ASHRAE, & EPA requirements for use with HVAC systems and has no VOCs or detectable odors. It is recommended that a TAB contractor be used to measure existing case air flow leakage so savings can be captured for incentive purposes and also to identify the “worst-case” units.

An alternative, lower-cost project would be to target the “worst-case” AC units and make sheet metal repairs to reduce air leakage using in-house labor by UMass facility staff.

ENERGY SAVINGS METHODOLOGY The savings for this measure were calculated in eQuest by modeling the base case AC units with 5% air loss and parametrically changing the proposed case to 1% air loss. This was modeled by changing the following eQuest parameters: SUPPLY-KW/FLOW, MIN-OUTSIDE-AIR, and SUPPLY-FLOW. Savings are primarily a result of reduced fan energy, as the supply fan will need to do


less work to supply the same amount of cooling air to the spaces. A heating penalty is expected from reduced fan heat - as the fan VFDs ramp down to provide the same cooling to the spaces with less air leaks, the amount of fan heat in the hot deck air stream will also be reduced.


COST ESTIMATE




(978) 208 - 0609

Total


1 2 Composite Sealing Material ea 21 $12,000 $252,000 $150 $0 $252,000

2 4 Misc Ductsealing ea 21 $200 $4,200 $150 1 8 $25,200 $29,400

3 3 As-Builts ea 1 $0 $150 1 4 $600 $600


5 ea $0 $150 $0 $0

6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $294,600

1 Means




Notes 1 Apply to AC-1 through AC-21 Commissioning 5% $17,700



Total $442,100

Sources

Opinion of Probable Construction CostECM 18.00 (f)-6: Air Sealing Repairs on AC Units



ECM 18.00 (F)-7 OPTIMIZE STATIC PRESSURE RESET

MEASURE ECONOMICS SUMMARY ECM # 18.00 (f)-7 Optimize Static Pressure Reset


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings

Steam Savings

Steam Cost

Savings

Total Cost

Savings

Retrofit Cost

Payback Before

Incentive


30,479 $3,048 7,096 $852 -7 -$73 $3,826 $27,800 7.3

BASE CASE Several ACs appear to have no static pressure reset, although sequence documents indicate they should have static pressure reset. Table below shows AC unit static pressure sequence information and trend observations; the units highlighted in yellow appear indicate opportunities to fix or repair these sequences.

Figure 115: Summary of static pressure sequence observations

SP Control

and Reset?

Min Static

(in wc)

Max Static

(in wc)

SP

Control?

SP

Reset?Trend Review - Notes

AC-1 Y 1.1 2.75 Y Y Resets 2.5 - 3.5 No

AC-2 Y 1.75 2.8 Y N Three manual changes observed, 1.75 to 2.0 Yes

AC-3 Y 2 2.5 Y Y Resets ~1.5 - 2.5 No

AC-4 Y 1.8 2.1 Y Y Resets 0.7 - 1.6 No

AC-6 Y 1.6 2.8 Y Y Reset to 1.5 - 2.5 No

AC-7 Y 1.7 2.75 Y Y Reset to 1.5 - 2.5 No

AC-8 Y 2.5 2.6 Y Y Reset to 1.5 - 2.5 No

AC-9 Y 2.6 2.9 Y Y Reset to 1.5 - 2.5 No

AC-10 Y 1.6 1.6 Y Y Reset to 1.5 - 2.5 No

AC-11 Y 1.2 2.8 Y Y Reset to 1.5 - 2.5 No

AC-12 Y 1.6 2.7 N/A N/A No static pressure data available. No

AC-13 Y 1.4 3 Y N Constant 1.25 Yes

AC-14 Y 2.5 2.5 Y Y Resets to 1.3 - 1.8 No

AC-15 Y 2 2 Y N Constant (Noise) 1 - 1.4 Yes

AC-16 Y 1.5 1.5 Y N Constant 1.9 Yes


AC-18 Y 1.3 1.8 N/A N/A N/A, Unit is off during trend period. No

AC-19 Y 2 2 Y N Mostly constant 1.25, dips occasionally to 0.75 Yes



TREND REVIEW Observations Static

Pressure

Reset

Opportunity?

Unit

Number

NORESCO Sequence


Figure 116: Summary of design data for units involved in measure

PROPOSED CASE Implement outside air temperature-based static pressure reset for the AC units identified above. The table below shows preliminary reset schedules.

Note: UMass indicated during the 50% draft report review that most of the air handlers with fixed static pressure set-points were adjusted due to pressurization concerns with the adjacent Hospital building. UMass should provide guidance on whether these are temporary or permanent adjustments. There are no savings for this measure if the adjustments for pressurization are permanent.

Figure 117: Summary of proposed case sequences for units involved in measure


Unit

Number

Measured

CFMMotor HP

AC-2 31,609 100

AC-13 26,111 60

AC-15 23,351 75

AC-16 13,093 40

AC-17 20,293 50

AC-19 20,464 75

AC-20 25,730 60

AC-21 20,856 60

Unit

Number

Static Pressure

Setpoint @ 80 F

OAT

Static Pressure

Setpoint @ 60 F

OAT

∆P

AC-2 2.00 1.50 0.50

AC-13 1.25 0.75 0.50

AC-15 1.40 0.90 0.50

AC-16 1.90 1.40 0.50

AC-17 1.25 0.75 0.50

AC-19 1.25 0.75 0.50

AC-20 1.25 0.75 0.50

AC-21 1.25 1.00 0.25


The energy savings associated with this measure were estimated using a parametric run of the baseline eQuest model. The run changed the supply fan “EIR f(PLR)” performance curve that calculates fan input power as a function of airflow part load ratio. The curve used in the base case is the standard curve available from the eQuest library. A custom curve was developed for the proposed case to model a demand-based duct static pressure reset.


COST ESTIMATE




(978) 208 - 0609

Total


1 3 Programming ea 8 $0 $150 1 4 $4,800 $4,800

2 3 Allowance for SP sensor replacement ea 2 $250 $500 $150 1 4 $1,200 $1,700

3 3 Sensor Calibration ea 8 $0 $150 1 4 $4,800 $4,800

4 3 As-Builts ea 1 $0 $150 1 8 $1,200 $1,200


6 ea $0 $150 $0 $0

7 ea $0 $150 $0 $0

8 ea $0 $150 $0 $0

9 ea $0 $150 $0 $0

10 ea $0 $150 $0 $0

Subtotal $14,900

1 Means







Total $27,800

Opinion of Probable Construction CostECM 18.00 (f)-7: Optimize Static Pressure Reset


Sources

432 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Central CHW Pumping

ECM-21.02 (F) SCHOOL SOLAR HOT WATER

MEASURE ECONOMICS SUMMARY ECM # 21.02 (f) School Solar Hot Water


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


0 $0 0 $0 929 $9,288 $9,288 $338,601 36.5

MEASURE DESCRIPTION Solar water heating is the conversion of sunlight into renewable energy for water heating using a solar thermal collector. The solar hot water system proposed by BEAM for the School includes a glazed flat plate collector system inclined at 35°F facing south with a total surface area of 4,045 ft2. The target loads for the heating system in the School building are showers and bathroom sinks, which are estimated at 5,500 gallons/day. The system would include a buffer tank to be installed in the B-level mechanical room. For more details, refer to the BEAM’s report in the Appendix, which includes additional details on the proposed solar hot water systems for the Hospital and School buildings.


CENTRAL PLANT CHW PUMPING EXECUTIVE SUMMARY

Notes: The cost savings figures in the summary table above assume the following utility rates: $0.10/kWh, $0.12/ton-hour, and $10.00/Mb.

ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total

Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


04-03 (g)-1 Coversion to Variable Primary Pumping 506,103 0 0 $50,610 $191,575 3.8

04.13 (g)-1 Coordinated Control of Primary & Tertiary Pumping 20,679 0 0 $2,068 $17,000 8.2

526,782 0 0 52,678 208,575 4.0TOTALS


FACILITY DESCRIPTION Power, steam, and chilled water production have been intertwined since the inception of the UMass Medical School’s Central Plant in 1972. For the first 25 years of operation the plant operated as a 250 psig steam plant that provided heat, electricity, and chilled water to the medical school. Combination condensing and 50 psig extraction steam turbines (STC-1 and STC-2) provide 4,160V power and 50 psig steam used for heating the majority of buildings on campus.

In support of the 2000 expansion at the Medical School, the existing plant was significantly expanded in 2001 and again in 2012 to accommodate the increasing campus load in addition to improving the overall plant efficiency and carbon footprint. The following equipment currently makes up the plant:

One nominal 7.5MW Solar Gas Turbine complete with 60,000 pph 1,100 psig

(superheated) HRSG complete with supplementary duct burner

Two 115,000 pph/each 1,100 psig (~840°F steam supply) boilers B-3 and B-4 augment

steam capacity during periods of high 1,100 psig steam demand

Two 80,000 pph/each saturated steam 250 psig steam Boilers B-1 and B-2

One 5 MW 1,100 psig topping (backpressure) turbine (STC-3) operating with an inlet

pressure of 1,100 psig (superheated) and an exhaust pressure of 250 psig saturated

Two 2.5 MW/each 250 psig inlet combination 50 psig extraction and condensing

turbines (STC-1 and STC-2)

15,410 ton chilled water plant consisting of (5) York field-erected centrifugal chillers

o (3) 2,470 ton York Titan steam turbine driven chillers (250 psig inlet) (CH-1, 2,

and 3)

o (1) 4,000 ton York Titan steam drive chiller (CH-4) with 50 psi extraction

matching condensing turbine (creating a tri-gen steam plant operating mode).

o (1) 4,000 ton York Titan electric centrifugal chiller (CH-5)

o The lead summer chiller is the 4,000 ton 50 psig inlet Chiller CH-5. During the

Fall/winter/spring months (November to ~March) the 4,000 ton electric chiller is

the lead means of cooling.

The following table displays each chillers tonnage, design CHW flow, the differential temperature, the design condenser water flow, as well as the design steam inlet pressure.


Table 26: Chiller Summary

Each chiller is equipped with its own dedicated primary CHW pump. The following is the control sequence for the primary loop pumps:

Constant speed primary pumps are used to circulate cooling water in the main campus loop. A remote differential pressure sensor located in the basement of the Hospital Building is used to stage “on” or stage “off” a “lag” chiller. The lag machine is started when the Hospital dP approaches 10 psig. A differential bypass valve located chiller plant basement opens to maintain a high limit of 40 psig in the hospital basement.

Loop capacity is based on 1.6GPM per ton of refrigeration.

Chilled water can be introduced to the loop from two locations. Chillers CH-1 thru CH-4 feed a 30” header that feeds the campus loop from the west and CH-5 feeds and 24” header that feeds the main campus loop from the South. Refer to the attached “Campus Chilled Water Schematic”.

During the winter, the electric centrifugal chiller will handle the entire load. During summer operation, the electric chiller is the first stage of cooling, and CH-4 (York-Titan Steam Turbine) is the secondary stage of cooling.

Chiller

Tag

Year

Installe

d

Type TonageCHW

(GPM)CHW (dT) CW (GPM)

Inlet

Pressure

1

York -Titan Steam

Turbine driven

Centrifugal Chiller

(Original Plant)

2470 3952 15ᵒ 7500 250

2

York -Titan Steam

Turbine driven

Centrifugal Chiller

(Original Plant)

2470 3952 15ᵒ 7500 250

3

York -Titan Steam

Turbine driven

Centrifugal Chiller

(Original Plant)

2470 3952 15ᵒ 7500 250

4

York -Titan Steam

Turbine driven

Centrifugal Chiller

4000 6400 15ᵒ 12000 50

5 2009

York -Titan Electric

Electric Centrifugal Chiller

(South Expansion Bldg)

4000 6400 15ᵒ 8000 NA

15410Gross load

UMass Medical Chiller Summary


The meter location drawing shown in Figure 118 displays the primary CHW loop piping configuration for the UMass Medical Center campus.

Figure 118: Campus Chilled Water Schematic


The following tables display each primary and tertiary pump location, nameplate horsepower, design head, and design flow.

Table 27: Primary CHW Loop Pumps

Table 28: Tertiary Pump Summary

Pump

TagPump Location Description Chiller/Equipment served VFD HP Head (ft)

Estimated Flow

Req. (GPM)

1 Basement of the CHP Plant Primary CHW Pump CH-1 no 200 175 3,750




5 Basement of the CHP Plant Primary CHW Pump NA no 250 NA NA

61st Floor South Chiller

Expansion BldgPrimary CHW Pump 5 and 6(future) no 300 137.5 6,700

71st Floor South Chiller

Expansion BldgPrimary CHW Pump 5 and 6(future) no 300 137.5 6,700

Umass Medical CHW Pump Summary

Pump

TagPump Location Description Chiller/Equipment served VFD HP Head (ft)

Estimated Flow

Req. (GPM)

CHWP-1 ACC - Penthouse Variable SCHW Pump AHUs, FCUs Yes 7.5 30 700



PC-IU-1A HSP - Penthouse Variable Booster CHW Pump Induction Units Yes 10 35 630

PC-IU-1T HSP - Penthouse Variable Booster CHW Pump Induction Units Yes 10 35 630

(7) PC-XT HSP - Penthouse Variable Coil CHW Circulators (7) Penthouse AHUs Yes 5 35 300-640, different

for each coil

SCHP-1 LRB Variable SCHW Pump AHUs Yes 125 80 4800

SCHP-2 LRB Variable SCHW Pump AHUs Yes 125 80 4800

SCHP-3 LRB Variable Process CHW (HE-7) Process Yes 15 80 370

SCHP-4 LRB Variable Process CHW (HE-7) Process Yes 15 80 370

Umass Medical CHW Tertiary Pump Summary


The tertiary pumps in each building modulate to maintain the building’s dP set point. Currently, the primary CHW pumps provide enough flow year-round that the tertiary pumps seldom run. This is due to the primary CHW pumps providing enough flow and pressure that the buildings dP set point is often satisfied with the tertiary pumps staged off.


CENTRAL PLANT LOAD CALIBRATION The chilled water tonnage and flow was based off of operator logs for the chiller plant. The operator logs contained the minimum and maximum flow and tonnage per each day from January 2014 to October 22, 2014. Outside air temperature for Worcester, MA was obtained from the NOAA website for the same date range as the operator logs. The following graphs display the regression analysis conducted on the central plant load.

Figure 119: OA Temperature vs. Operator Log CHW Flow

Figure 120: OA Temperature vs Operator Log Tonnage

y = 0.0312x3 - 1.7809x2 + 28.511x + 5579 R² = 0.7396

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

0 10 20 30 40 50 60 70 80 90 100

GP

M

OA DRYBULB TEMPERATURE (°F)

OA TEMPERATURE VS. OPERATOR LOG CHW FLOW

y = 0.0226x3 - 1.6527x2 + 44.35x + 1003.5 R² = 0.772

-

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

9,000

10,000

0 10 20 30 40 50 60 70 80 90 100

TON

S

OA DRYBULB TEMPERATURE (°F)

OA TEMPERATURE VS. OPERATOR LOG TONNAGE


The regression analysis curves were used to project the annual tonnage as well as flow. A TMY3 Worcester MA weather file was used to develop the annual cooling and flow profile used for the projection of the annual tertiary pump consumption. The calculation of the tertiary pump consumption was conducted using a bin-based analysis. Design dP set points, BHPs, and design flows were gathered for all buildings equipped with tertiary pumps. The tertiary pump bin analysis was used to project the penalty associated with the variable primary pumping measure, as well as the savings associated with resetting the tertiary pump dP set-points based on building load.


The two Energy Conservation Measures (ECMs) associated with the electric and steam driven chillers, primary pumps, and tertiary pumps were identified following field investigations and a review of trend data provided by central plant staff. The two measures that were identified involve installing VFDs on the primary CHW loop pumps, as well as resetting the tertiary loop dP set-point in all buildings equipped with tertiary pumps as a function of the building’s load.

ECM 4.03-1 – CONVERSION FROM CONSTANT VOLUME PRIMARY TO

VARIABLE PRIMARY PUMPING

MEASURE ECONOMICS SUMMARY ECM # 04-03 (g)-1 Coversion to Variable Primary Pumping


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


506,103 $50,610 0 $0 0 $0 $50,610 $191,575 3.8

BASE CASE The central plant operates at a fixed flow rate per chiller and the gross plant flow is set by the number of chillers on line at any one time. A dP sensor in the basement of the Hospital building is used to stage chillers “on” and “off” plus control the chiller plants “high pressure” dP bypass. Plant operators manually added or subtracted chillers to meet the loop the following requirements:

Chiller plant dT less than 15°F

Hospital basement chilled water dP greater than 10 psig

Several of the campus buildings are equipped with tertiary pumps that cycle “on” or “off” to maintain the fixed building dP set point.

Based on a review of the trend data, we observed that the primary CHW loop was being used to provide the hydraulic head necessary to pump the chilled water through all of the buildings. As a result, the tertiary loops in the Sherman, LRB, and ACC facilities seldom ran. The overall plant efficiency could be improved if the large primary CHW pumps were modulated to maintain a fixed loop set point in lieu of using the bypass for flow control, and the tertiary pumps were used to maintain their respective building dP set point.

PROPOSED CASE We propose adding a VFD to the constant speed primary pump associated with chiller #5 and automating the existing VFD control on chiller #6. This will allow the system to maintain a constant 10 psig in the basement of the hospital building at all times thus reducing the flow and static head required to meet a given chilled water load. Every 10 minutes, the new primary


pump(s) VFD PID control loop shall look at the differential pressure error (dPvalue minus dPsetpoint) associated with each building. An error “high select” shall be performed to find the building that is most below is dP set-point. This value will be used in the primary pump PID control loop. The primary pump speed(s) shall modulate up and down to maintain each building “bridge” dP set-point. Buildings without tertiary pumps would have a 10 psig minimum and buildings with tertiary pumps would maintain dP necessary to provide the required flow target.

Variable Primary Building Loop Polling (or error high select)

o Buildings with and without tertiary pumps shall have their main loop dP compared to their dP set-point every 10 minutes. The central plant based Distributed Control System (DCS) shall perform an error "high select" (Pressure – Pressure set-point) and use the most hydraulically remote point to control the chiller plants variable primary pumps.

o The main chiller plant flow bypass valve shall only be allowed to open to maintain a minimum flow through the chiller(s). We have estimated this to be 50% of the cooler design flow.

Energy savings are achieved primarily due to converting the system from primary (constant flow) to variable primary flow control.

ENERGY SAVINGS METHODOLOGY This savings associated with this measure were projected by using the annual central plant chilled water load created with a regression analysis. The tertiary pump penalty associated with this measure was generated using a bin based approach. Tertiary pump information, including design GPM, BHP, and tertiary loop dP, were used in this analysis to project the total tertiary pump consumption.


COST ESTIMATE The implementation costs for this project include the installation networking of the chiller plants DCS to the campuses BAS. All new pump algorithms will be located on the DCS platform to allow for single point tuning of the entire loop.


100 Burtt Rd. Ste. 212 Address: CHW Plant Estimated By: MM


(978) 208 - 0609

Total


1 3 VFDs on Primary CHW Pumps ea 2 $0 $150 2 6 $3,600 $3,600

2 3 DCS Controls Programming $150 1 40 $6,000 $6,000

3 2 300HP VFD ODP PE Motor (18 pulse) ea 1 $18,450 $150 3 24 $10,800 $29,250

4 2 300 HP 12 pulse VFD ea 1 $19,525 $150 3 24 $10,800 $30,325

5 3

VFD connection to DCS (via Modbus) and

terciary pump control to DCS (via new

BacNet bridge) ea 1 $10,000 $150 2 40 $12,000 $22,000

6 3 Shaft Grounding $4,500

7 3 Contractor Commissioning ea 1 $150 1 40 $6,000 $6,000

8 3 As-Builts ea 1 $0 $150 1 8 $1,200 $1,200

Subtotal $102,875

1 Means







Total $191,575

Opinion of Probable Construction CostECM-4.03-1: Variable Primary


Sources


ECM 4.13-1– COORDINATED CONTROL OF THE CHP PRIMARY AND

BUILDING TERTIARY PUMPING

MEASURE ECONOMICS SUMMARY ECM # 04.13 (g)-1 Coordinated Control of Primary & Tertiary Pumping


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


20,679 $2,068 0 $0 0 $0 $2,068 $17,000 8.2

BASE CASE Currently, the Building Automation System (BAS) controls all tertiary building pumps and the distributed control system (DCS) in the main chilled water plant controls the variable primary loop pressure. This strategy has both systems operating independently of each other. As a result, the plant’s pumps tend to work harder during periods of low to intermediate load. They are handling their loop pressure duties plus the building pressure load (necessary to circulate water through the HVAC equipment).

PROPOSED CASE We propose “cascading” (resetting) each building fixed dP set-point based on its chilled water demand. Closing all bypasses and cascading each building dP set-point will reduce each building’s tertiary pumping electrical consumption.

Buildings with and without tertiary pumps shall have their main loop dP pressure compared to their set-point every 10 minutes. All chilled water valves will be polled every 10 minutes and the 10 most open valves position shall be averaged. The “building” dP set-point will be reset based on the following algorithm:

o If the average of the 10 most open chilled water valves position is 90% open, decrease the dP set-point by 0.1 psi in a cascading fashion.

o If the average position is between 90% and 95% open, the dP set-point shall not change.

o If the average position in above 95% open, the loop dP set-point shall be increased in 0.1 psi increments (up to maximum) in a cascading fashion.

In order to protect the pumps, a low limit of 20 Hz shall be used on the pumps. The tertiary pumps shall be staged off when the loop is at minimum for 15 minutes. The tertiary pumps shall be staged back on when the 10 most open cooling coil valves are open 95% for 15 minutes.


Energy savings are achieved primarily due to the reduction in tertiary pumping when the building is at part load and it can reset the dP set-point while maintaining the space temperatures in their dead-band.

ENERGY SAVINGS METHODOLOGY The tertiary pump savings were calculated using a bin based analysis. Information on the tertiary pump design GPM, BHP, and the tertiary pump dP set points were used. The dP reset sequence was modeled as a function of the building load.


COST ESTIMATE The implementation cost for this project include all programming required to implement the dP reset on the tertiary loop level as a function of the output of polling all of the chilled water valves in the building.


100 Burtt Rd. Ste. 212 Address: CHW Plant Estimated By: MM


(978) 208 - 0609

Total


1 3 Controls Programming ea 1 $0 $150 1 40 $6,000 $6,000


3 3 As-Builts ea 1 $0 $150 1 4 $600 $600

Subtotal $9,000

1 Means







Total $17,000

Opinion of Probable Construction CostECM-4.13-1: Tertiary Loop dP Reset


Sources

447 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Renewables

SOLAR PHOTOVOLTAIC EXECUTIVE SUMMARY

Notes: The cost savings figures in the summary table above assume the following utility rates: $0.10/kWh, $0.12/ton-hour, and $10.00/Mb.

ECM # ECM

Electric

Energy

Savings

CHW

Energy

Savings

Steam

Savings

Total Cost

Savings

Retrofit

Cost

Payback

Before

Incentive


21-01 (g)-1 Sherman Center Rooftop PV Array 123,864 0 0 $12,386 $331,294 26.7

21-01 (g)-2 Quad Four Dual-Axis Tracker PV Array 83,823 0 0 $8,382 $239,904 28.6

21-01 (g)-3 Plantation Hillside Fixed Tilt PV Array 807,946 0 0 $80,795 $1,783,939 22.1

21-01 (g)-4 South Road Garage Canopy PV Array 416,250 0 0 $41,625 $2,214,300 53.2

21-01 (g)-5 Plantation Street Garage Canopy PV Array 777,394 0 0 $77,739 $4,187,040 53.9

21-01 (g)-6 First Road Garage Canopy PV Array 1,447,701 0 0 $144,770 $7,612,800 52.6

TOTALS 3,656,978 0 0 $365,698 $16,369,277 44.8


ECM 21-01 (G)-1 SHERMAN CENTER ROOFTOP PHOTOVOLTAIC ARRAY

MEASURE ECONOMICS SUMMARY ECM # 21-01 (g)-1 Sherman Center Rooftop PV Array


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


123,864 $12,386 0 $0 0 $0 $12,386 $331,294 26.7

MEASURE DESCRIPTION A description of this measure is included below, from Page 10 of the renewables report by Zapotec:

A self-ballasted PV array of 104 kW is feasible for the roof of Sector A of the Albert Sherman Center. Modules would be supported at a tilt of 10° from horizontal on a racking system that is held in place with concrete ballast blocks, eliminating the need for mechanical attachments to the roof. The DC power from the array would be combined to feed a 100 kW inverter. The inverter itself has an outdoor-rated enclosure that would allow its installation on the rooftop to reduce power losses in the DC wire runs and save space in electrical rooms. The AC output from the inverter would run in conduit from the roof to an outdoor AC disconnect, which is required by National Grid, and then to one of the building’s 480 VAC AC distribution panels for interconnection.

The low profile of the modules means that this system is out of sight from the ground, but it will be visible from the upper floors of nearby buildings. The proposed system is expected to produce approximately 124,000 kWh of electricity per year.


ECM 21-01 (G)-2 QUAD FOUR DUAL-AXIS TRACKER PHOTOVOLTAIC

ARRAY

MEASURE ECONOMICS SUMMARY ECM # 21-01 (g)-2 Quad Four Dual-Axis Tracker PV Array


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


83,823 $8,382 0 $0 0 $0 $8,382 $239,904 28.6

MEASURE DESCRIPTION A description of this measure is included below, from Pages 24-26 of the renewables report by Zapotec:

Quad Four (Q4) is a grassy area along Route 9 near the South Parking Garage, and is currently under renovation to improve drainage and visual appeal. The proposed configuration includes highly seven Allsun 24-module dual-axis trackers, standing up to 20 feet at their upper edge when tilted toward the horizon. Each table of modules will track the sun across the sky throughout the day for maximum yield. The practical benefit of this dual-axis tracking method is the extension of power production throughout the day, which can cause a 40-45% increase in energy output. Further production advantages over fixed systems can be expected due to the trackers’ superior ability to shed snow and thus operate with no daytime snow coverage throughout the winter. Seven trackers outfitted with high-efficiency modules comprise a 47 kW system capable of producing approximately 84,700 kWh per year.


ECM 21-01 (G)-3 PLANTATION HILLSIDE FIXED TILT PHOTOVOLTAIC

ARRAY

MEASURE ECONOMICS SUMMARY ECM # 21-01 (g)-3 Plantation Hillside Fixed Tilt PV Array


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


807,946 $80,795 0 $0 0 $0 $80,795 $1,783,939 22.1


There is an area of open land up the hill from the new Plantation Street Garage which is owned by Worcester City Campus Corporation (a subsidiary of UMass Medical Center). Conveniently clear of trees, this area is the most feasible location for larger scale PV development on UMass Medical property.

The proposed configuration is a fixed tilt PV system with a high tilt table, which are more practical for this sort of application than lower-tilt or ballasted systems because shading considerations necessitate a significant spacing between rows (in this case, over 20 feet), and this makes vegetation maintenance considerably easier. The lower edge of the array is typically over two feet from the ground as well, requiring less frequent mowing. The proposed 617 kW PV array, installed at a tilt of 20° is expected to produce approximately 808,000 kWh of electricity per year.


ECM 21-01 (G)-4 SOUTH ROAD GARAGE CANOPY PHOTOVOLTAIC ARRAY

MEASURE ECONOMICS SUMMARY ECM # 21-01 (g)-4 South Road Garage Canopy PV Array


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


416,250 $41,625 0 $0 0 $0 $41,625 $2,214,300 53.2


The South Road Parking Garage is located at the University of Massachusetts Medical Center main campus next to Route 9 in Worcester. It consists of 5 levels for patient and visitor parking. The top level is open with a 3-foot tall parapet wall, a few light poles, and two curtain wall staircases located at the south-east and south-west corner of the garage. Two separate car ramps going in opposite directions are at the center of the top floor. There are a total of 93,600 square feet of open parking spaces on the top level. An office building lies adjacent to the west side of the garage at a height of 6 stories above the top floor of the garage.

The PV canopies at the South Road Garage should not extend the width of the building due to the shade cast by the tall building to the west of the garage. The inverters, DC and AC disconnect switches would be located on the same rooftop level as PV canopies. Placing this equipment in a partially shaded area is recommended, as it would not take up the space of completely shaded parking spots created by the canopies. Choosing the northeast corner of the garage would reduce the wire length to the interconnection point in the electrical room on the first level.


ECM 21-01 (G)-5 PLANTATION STREET GARAGE CANOPY PHOTOVOLTAIC

ARRAY

MEASURE ECONOMICS SUMMARY ECM # 21-01 (g)-5 Plantation Street Garage Canopy PV Array


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


777,394 $77,739 0 $0 0 $0 $77,739 $4,187,040 53.9


The Plantation Street Parking Garage is a newly built 7-level parking garage (elevation of 45 feet) located in the northern section of the UMass Medical campus. Its top level consists of a total of 65,000 square feet of area. A ramp sloping down northward is at the center of the top floor. Curtain walls 16 feet tall are located at south-east, north-west, and north-east corners of the garage. No other buildings near the garage cause shading concerns.

The Plantation Street Parking Garage with a photovoltaic canopy system tilted at 5 degrees can accommodate a 698 kW DC-sized system. This system can produce around 777,394 kWh a year.


ECM 21-01 (G)-6 FIRST ROAD GARAGE CANOPY PHOTOVOLTAIC ARRAY

MEASURE ECONOMICS SUMMARY ECM # 21-01 (g)-6 First Road Garage Canopy PV Array


Electric Cost

Savings

CHW Energy Savings

CHW Cost

Savings Steam

Savings

Steam Cost

Savings

Total Cost

Savings Retrofit

Cost

Payback Before

Incentive


1,447,701 $144,770 0 $0 0 $0 $144,770 $7,612,800 52.6


The First Road Parking Garage, erected in the mid-1980s, has 6 levels for parking and multiple ramps at different levels for entering and exiting vehicles. The garage’s effective “roof” is split between the 6th level and the 4th level. The top level (6th) has approximately 80,000 square feet of parking spaces on the west side, overlooking the 4th floor of the east end of the garage, which has an area of 28,000 square feet. A 9-story office building located southeast of the garage on the corner of First Road and Third Road is a likely shading concern. There is also possible shading from trees to the south of the garage. The First Road Parking Garage can accommodate 1,269 kW DC of PV modules tilted at 5 degrees. The energy produced would be 1,447,701 kWh per year.

454 DCAMM UMMC Worcester, MA | AL2 Energy Audit | ECM Summary Tables

ADDITIONAL ECM SUMMARY TABLES

ECMS BY BUILDING & MEASURE CATEGORY

ECM # ECM

Electric Energy

Savings

CHW Energy

Savings Steam Savings

Total Cost

Savings Retrofit Cost

Payback Before

Incentive


01.01 (a) Lighting - Lamps, Ballasts, and Fixtures

01.01 (a) Lighting Retrofit 83,832 0 0 $10,060 $116,710 13.9

04.09 (a) EMS and Controls - Re-Commission/Expand Existing BMS Controls

04.09 (a)-1 Tighten Occupancy Schedules 40,288 35,207 1,605 $25,106 $30,625 1.2

04.09 (a)-2Install New Occupancy Sensors for HVAC

Control95,875 30,917 1,276 $27,976 $708,110 25.3

09.00 (a) VFD's (Variable Frequency Drives)

09.00 (a) Retrofit AHU-5 Supply Fan with VFD 8,648 0 0 $1,038 $23,000 22.2

18.00 (a) Retro-Commissioning

18.00 (a)-1 Replace Weather Station 251 39,269 -23 $4,516 $12,700 2.8

18.00 (a)-2Calibrate Flow Stations & Reduce

Unoccupied OA-3,015 63,186 2,039 $27,614 $35,100 1.3

18.00 (a)-3 Static Pressure Reset on AHUs 1-4 162,714 27,859 -182 $21,046 $38,200 1.8

18.00 (a)-4Reprogram Discharge Temperature Reset on

AHUs 1-4-3,020 73,412 280 $11,250 $20,300 1.8

18.00 (a)-5 Reduce AHU-2 OA Damper Minimum Position -236 5,654 320 $3,852 $7,700 2.0

18.00 (a)-6 Calibrate Zone CO2 Sensors 0 19,892 0 $2,387 $52,200 21.9

18.00 (a)-7 Replace AHU-4 Return Air CO2 Sensor 0 6,703 0 $804 $3,500 4.4

18.00 (a)-8 Reduce VAV Unoccupied Flow Set-points -4,505 183,954 2,429 $45,827 $389,900 8.5

18.00 (a)-9Reprogram Zone Set-points & Implement

Deadband271,440 123,813 3,595 $83,380 $55,650 0.7

18.00 (a)-10Reprogram Unoccupied Zone Temperature

Control0 0 361 $3,615 $8,613 2.4

ACC Subtotals 652,272 609,866 11,701 $268,471 $1,502,308 5.6

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


01.01 (b) Lighting - Lamps, Ballasts, and Fixtures

01.01 (b) Lighting Retrofit 57,116 0 0 $5,712 $110,150 19.3

02.01 (b) Lighting Controls - Lighting Occupancy Sensors

02.01 (b) Install Occupancy Sensors 129,208 9,802 -293 $11,171 $67,100 6.0

04.09 (b) EMS and Controls - Re-Commission/Expand Existing BMS Controls

04.09 (b)-1 FCU Controls Upgrade 244,142 25,308 3,297 $60,423 $848,600 14.2

04.09 (b)-2 HW Loop dP Reset 7,258 0 -22 $501 $8,100 16.2

12.04 (b) Windows and Doors - Low-E Window Film

12.04 (b) Install Low-E Window Film 5,083 5,661 7 $1,253 $90,800 72.5

Benedict Subtotals 442,807 40,771 2,989 $79,060 $1,124,750 14.2

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


01.01 (c) Lighting - Lamps, Ballasts, and Fixtures

01.01 (c) Lighting Retrofit 524,392 0 0 $52,439 $1,025,490 19.6

04.02 (c) EMS and Controls - Outside Air Control and Economizer

04.02 (c)Comparative Enthalpy Economizer on AHU-

1L, 1R, 1T-7T1,827 168,536 -13 $20,277 $36,850 1.8

04.09 (c) EMS and Controls - Re-Commission/Expand Existing BMS Controls

04.09 (c)-1Reconfigure Preheat Circulator Enable

Sequence on AHU-1B-6B3,255 0 0 $326 $11,400 35.0

04.09 (c)-2Reconfigure AHU-15T/16T Preheat

Temperature Control84 20,813 229 $4,792 $5,800 1.2

04.09 (c)-3Increase AHU-10T & 11T Minimum Discharge

Set-point187 8,722 70 $1,767 $5,800 3.3

Ambulatory Care Center (ACC)

Benedict

Hospital

04.09 (c)-4Hot Water Loop Differential Pressure Reset

Schedule120,840 0 -384 $8,245 $12,000 1.5

04.11 (c) EMS and Controls - HVAC Modifications: Add New Systems

04.11 (c)Reconfigure Preheat & Discharge Reset

Schedules on AHU-1B-6B0 281,337 5,468 $88,437 $120,700 1.4

04.14 (c) EMS and Controls - Exhaust Hood Occupancy Controls

04.14 (c) Kitchen Hood Controls 43,857 14,479 2,429 $30,413 $184,800 6.1

17.03 (c) Unknown HVAC - AHU: Replace CV with VAV

17.03 (c)-1Complete VAV Conversion on AHU-1B-6B &

1T,2T,3T,4T,6T,7T5,256,107 2,983,462 41,457 $1,298,198 $6,562,276 5.1

17.03 (c)-2Retrofit Fans with VFDs & Install Branch Duct

Dampers2,429,314 1,165,401 13,359 $516,368 $3,306,679 6.4

17.03 (c)-3Retrofit Fans with VFDs & Reset Speed vs

OAT3,025,217 3,394,859 43,237 $1,142,278 $929,379 0.8

18.00 (c) Retro-Commissioning

18.00 (c)-1Replace Preheat Valves & Actuators on AHU-

1B-6B, 1T-7T0 33,302 400 $7,992 $83,700 10.5

18.00 (c)-2Lock-out Humidification & Calibrate Return

Air %RH Sensors0 0 2,408 $24,081 $38,200 1.6

18.00 (c)-3 Replace Leaking Preheat Valve on AHU-13T 0 12,333 148 $2,960 $5,000 1.7

18.00 (c)-4Duct Static Pressure Reset on AHU-1R,

15T/16T9,665 3,250 14 $1,492 $19,700 13.2

18.00 (c)-5 Adjust AHU-1L Temperature Control 27,088 10,771 36 $4,361 $4,100 0.9

18.00 (c)-6 Optimize Heat Exchanger Reset Schedule -1,566 0 526 $5,099 $12,000 2.4

18.00 (c)-7 Replace Leaking CHW Valve on AHU-11T 0 18,390 223 $4,435 $4,650 1.0

18.00 (c)-8Fix Mixed Air Dampers to Improve

Economizer-213 72,310 -533 $3,327 $22,500 6.8

21.02 (c) Renewable Energy Systems - Solar Water Heating

21.02 (c) Hospital Solar Hot Water 0 0 644 $6,437 $539,439 83.8

Hospital Subtotals 5,985,524 3,627,705 53,120 $1,565,077 $8,694,405 5.6

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


01.01 (d) Lighting - Lamps, Ballasts, and Fixtures

01.01 (d) Lighting Retrofit 61,418 0 0 $6,142 $133,865 21.8

04.09 (d) EMS and Controls - Re-Commission/Expand Existing BMS Controls

04.09 (d)Modify Mixed Air Temperature Control on

AHU 1-100 67,135 3,106 $39,119 $27,900 0.7

04.13 (d)EMS and Controls - Operational

Enhancements

04.13 (d)Install Occupancy Sensors in Operating

Rooms97,720 20,518 721 $19,448 $115,600 5.9

18.00 (d) Retro-Commissioning

18.00 (d)-1Discharge Air Temperature Reset on AHU 1-

10-41,322 810,228 12,559 $218,688 $33,700 0.2

18.00 (d)-2 Static Pressure Reset on AHU 1-8 198,073 49,857 -5 $25,736 $31,700 1.2

18.00 (d)-3Reconfigure Preheat Circulator Control on

AHUs 1-108,175 0 0 $817 $27,900 34.1

18.00 (d)-4 Optimize HWST Reset 4 0 547 $5,475 $8,200 1.5

18.00 (d)-5 Replace AHU-4 Return Temperature Sensor 0 1,074 6 $184 $3,900 21.2

18.00 (d)-6 Replace Leaking CHW Valve on AHU-2 0 131,378 1,651 $32,273 $8,150 0.3

Lakeside Subtotals 324,067 1,080,190 18,585 $347,882 $390,915 1.1

Lakeside

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


01.01 (e) Lighting - Lamps, Ballasts, and Fixtures

01.01 (e) Lighting Retrofit 1,270,300 0 0 $127,030 $302,250 2.4

03.00 (e) Electric Motors

03.00 (e) Replace Cage Washer Pump Motors 1,252 0 0 $125 $11,500 91.9

03.01 (e) Electric Motors - High Efficiency Motors w/ VFDs

03.01 (e)-1 EC Motors on Bio-Safety Cabinet Fans 58,412 0 0 $5,841 $167,148 28.6

03.01 (e)-2 EC Motors on DHW Circulators 35,222 0 0 $3,522 $40,544 11.5

03.01 (e)-3 EC Motors on AHU-10 & 11 23,063 4,527 27 $3,120 $16,500 5.3

03.01 (e)-4 Retrofit RO Water Pumps with VFDs 69,848 0 0 $6,985 $42,770 6.1

04.02 (e) EMS and Controls - Outside Air Control and Economizers

04.02 (e) Comparative Enthalpy Economizer on AHU-9 425 2,449 0 $337 $10,650 31.6

04.09 (e) EMS and Controls - Re-Commission/Expand Existing BMS Controls

04.09 (e)-1 Scheduling and Set-points on AHU-9 Zones 13,052 6,278 325 $5,306 $39,650 7.5

04.09 (e)-2 Reprogram AHU-7 Preheat Control Sequence 23,886 269,211 2,828 $62,976 $10,000 0.2

04.09 (e)-3 Reduce Air Change Rates in Labs 12,778 129,252 6,732 $84,109 $682,450 8.1

04.09 (e)-4 Hot Water Loop Differential Pressure Reset 940 0 34 $431 $10,000 23.2

04.09 (e)-5Process CHW Loop Differential Pressure

Reset7,874 0 0 $787 $20,500 26.0

04.11 (e) EMS and Controls - Outside Air Control and Economizers

04.11 (e)-1Heat Recovery on Make-up Air Units (AHU 1-

6)-300,403 9,269 20,367 $174,743 $995,504 5.7

04.11 (e)-2 Install Passive Chilled Beams in Labs 405,347 233,302 2,120 $89,734 $1,862,993 20.8

18.00 (e) Retro-Commissioning

18.00 (e)-1 Static Pressure Reset 321,723 89,563 -320 $39,718 $54,000 1.4

18.00 (e)-2 Discharge Air Temperature Reset -2,510 462,855 -693 $48,365 $17,200 0.4

18.00 (e)-3 Replace Leaking Preheat Valves 0 168,570 2,141 $41,634 $19,050 0.5

18.00 (e)-4 Replace Leaking Chilled Water Valve 0 41,958 533 $10,363 $10,425 1.0

18.00 (e)-5 Reduce AHU-9 Minimum Outdoor Air 16,536 14,135 1,347 $16,818 $8,500 0.5

18.00 (e)-6Reprogram AHU-10, 11 Zone Temperature

Set-points618 3,761 20 $716 $3,900 5.4

18.00 (e)-7Replace Preheat Face/Bypass Damper

Actuators235,436 7,635 3,529 $59,754 $14,400 0.2

18.00 (e)-8 Exhaust Fan Static Pressure Reset 213,924 0 0 $21,392 $6,600 0.3

18.00 (e)-9 Temperature Set-backs in Lab Corridors 3,465 15,823 954 $11,782 $19,500 1.7

18.00 (e)-10 Hot Water Supply Temperature Reset -956 0 4,304 $42,940 $6,600 0.2

Lazare Research Building Subtotals 2,410,232 1,458,588 44,248 $858,530 $4,372,635 5.1

Lazare Research Building

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


01.01 (f) Lighting - Lamps, Ballasts, and Fixtures

01.01 (f) Lighting Retrofit 799,421 0 0 $79,942 $1,197,300 15.0

03.01 (f) Electric Motors - High Efficiency Motors w/ VFDs

03.01 (f)-1 Retrofit FCU & FPB Fans With EC Motors 105,425 0 0 $10,543 $189,200 17.9

03.01 (f)-2Retrofit Enviro-Room Evap Fans with EC

Motors93,229 0 0 $9,323 $174,400 18.7

04.07 (f) EMS and Controls - DDC Controllers

04.07 (f) Upgrade Terminal VAV Mixing Box Controls 693,873 102,433 624 $87,919 $1,827,525 20.8

09.00 (f) VFD's (Variable Frequency Drives)

09.00 (f)-1 Loading Dock Variable Exhaust Controls 317,926 0 0 $31,793 $74,315 2.3

09.00 (f)-2 Reduce Lab Air Changes 1,108,663 505,892 7,047 $242,044 $807,463 3.3

09.00 (f)-3Install VFDs & CO2 Ventilation Controls on

Library ACs300,790 70,026 2,172 $60,203 $139,565 2.3

17.09 (f) Unknown HVAC - Add Economizer Capabilities

17.09 (f) Reclaim Return Air on AC-12 8,483 0 659 $7,442 $39,600 5.3

18.00 (f) Retro-Commissioning

18.00 (f)-1 Optimize Perimeter HW Reset 0 0 387 $3,874 $31,000 8.0

18.00 (f)-2 Auditorium Scheduling & Occupancy Controls 249,081 32,778 1,234 $41,182 $202,950 4.9

18.00 (f)-3 Repair Heating Valves & Actuators 0 220,569 5,274 $79,206 $59,050 0.7

18.00 (f)-4 Repair Cooling Valves & Actuators 0 74,420 173 $10,656 $18,250 1.7

18.00 (f)-5Repair Economizer Dampers & Optimize

Sequence61,505 639,057 7,186 $154,700 $259,900 1.7

18.00 (f)-6 Air Sealing Repairs on AC Units 276,499 20,259 -777 $22,310 $442,100 19.8

18.00 (f)-7 Optimize Static Pressure Reset 30,479 7,096 -7 $3,826 $27,800 7.3

21.02 (f) Renewable Energy Systems - Solar Water Heating

21.02 (f) School Solar Hot Water 0 0 929 $9,288 $338,601 36.5

Medical School Building Subtotals 4,045,373 1,672,529 24,901 $854,250 $5,829,019 6.8

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


04-03 (g) EMS and Controls - Variable Speed Drives

04-03 (g)-1 Coversion to Variable Primary Pumping 506,103 0 0 $50,610 $191,575 3.8

04-13 (g) EMS and Controls - Operational Enhancements

04.13 (g)-1Coordinated Control of Primary & Tertiary

Pumping20,679 0 0 $2,068 $17,000 8.2

Central Plant CHW Pumping Subtotals 526,782 0 0 $52,678 $208,575 4.0

ECM # ECM

Electric Energy

Savings

CHW Energy


Total Cost


Payback Before

Incentive


21-01 (g) Photovoltaic Modules

21-01 (g)-1 Sherman Center Rooftop PV Array 123,864 0 0 $12,386 $331,294 26.7

21-01 (g)-2 Quad Four Dual-Axis Tracker PV Array 83,823 0 0 $8,382 $239,904 28.6

21-01 (g)-3 Plantation Hillside Fixed Tilt PV Array 807,946 0 0 $80,795 $1,783,939 22.1

21-01 (g)-4 South Road Garage Canopy PV Array 416,250 0 0 $41,625 $2,214,300 53.2

21-01 (g)-5 Plantation Street Garage Canopy PV Array 777,394 0 0 $77,739 $4,187,040 53.9

21-01 (g)-6 First Road Garage Canopy PV Array 1,447,701 0 0 $144,770 $7,612,800 52.6

Photovoltaic Modules Subtotals 3,656,978 0 0 $365,698 $16,369,277 44.8

GRAND TOTAL 18,044,035 8,489,650 155,544 $4,391,646 $38,491,883 8.8

Solar Photovoltaic

Medical School

Central Plant CHW Pumping


ECMS BY BUILDING & GROUPED IMPLEMENTATION COSTS

BUILDING MEASURE CATEGORY MEASURE TYPE DESCRIPTION PAYBACK SAVINGS COST

ACC 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement01.01 (a) Lighting Retrofit 11.6 10,060$

ACC 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (a) Retrofit AHU-5 Supply Fan with VFD 22.2 1,038$ $139,710

ACC 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (a)-1 Tighten Occupancy Schedules 1.2 25,106$

ACC 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (a)-2 Install New Occupancy Sensors for HVAC Control 25.3 27,976$ $738,735

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-1 Replace Weather Station 2.8 4,516$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-2 Calibrate Flow Stations & Reduce Unoccupied OA 1.3 27,614$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-3 Static Pressure Reset on AHUs 1-4 1.8 21,046$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-4 Reprogram Discharge Temperature Reset on AHUs 1-4 1.8 11,250$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-5 Reduce AHU-2 OA Damper Minimum Position 2.0 3,852$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-6 Calibrate Zone CO2 Sensors 21.9 2,387$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-7 Replace AHU-4 Return Air CO2 Sensor 4.4 804$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-8 Reduce VAV Unoccupied Flow Set-points 8.5 45,827$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-9 Reprogram Zone Set-points & Implement Deadband 0.7 83,380$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-10 Reprogram Unoccupied Zone Temperature Control 2.4 3,615$ $623,863


BENEDICT 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement01.01 (b) Lighting Retrofit 19.3 5,712$

BENEDICT 02.00 Lighting Controls 02.01 Lighting Occupancy Sensors 02.01 (b) Install Occupancy Sensors 6.0 11,171$

BENEDICT 12.00 Window and Doors 12.04 Low-E Window Film 12.04 (b) Install Low-E Window Film 72.5 1,253$ $268,050

BENEDICT 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (b)-1 FCU Controls Upgrade 14.0 60,423$

BENEDICT 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (b)-2 HW Loop dP Reset 16.2 501$ $856,700


HOSPITAL 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement01.01 (c) Lighting Retrofit 19.6 52,439$

HOSPITAL 17.00 Unknown HVAC 17.03 AHU: Repair/Replace CV (Constant Volume) or IGV (Inlet Guide Vanes) with VAV (Variable Air Volume)17.03 (c)-1 Complete VAV Conversion on AHU-1B-6B & 1T,2T,3T,4T,6T,7T 5.1 1,298,198$

HOSPITAL 21.00 Renewable Energy Systems 21.02 Solar Water Heating 21.02 (d) Hospital Solar Hot Water 83.8 6,437$ $8,127,205

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.02 Outside Air Control, and Economizers04.02 (c) Comparative Enthalpy Economizer on AHU-1L, 1R, 1T-7T 1.8 20,277$

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (c)-1 Reconfigure Preheat Circulator Enable Sequence on AHU-1B-6B 35.0 326$

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (c)-2 Reconfigure AHU-15T/16T Preheat Temperature Control 1.2 4,792$

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (c)-3 Increase AHU-10T & 11T Minimum Discharge Set-point 3.3 1,767$

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (c)-4 Hot Water Loop Differential Pressure Reset Schedule 1.5 8,245$

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.11 HVAC Modifications - Add New Systems04.11 (c) Reconfigure Preheat & Discharge Reset Schedules on AHU-1B-6B 1.4 88,437$

HOSPITAL 04.00 EMS (Energy Management System) and Controls04.14 Exhaust Hood Occupancy Control 04.14 (c) Kitchen Hood Controls 6.1 30,413$ $377,350

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-1 Replace Preheat Valves & Actuators on AHU-1B-6B, 1T-7T 10.5 7,992$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-2 Lock-out Humidification & Calibrate Return Air %RH Sensors 1.6 24,081$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-3 Replace Leaking Preheat Valve on AHU-13T 1.7 2,960$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-4 Duct Static Pressure Reset on AHU-1R, 15T/16T 13.2 1,492$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-5 Adjust AHU-1L Temperature Control 0.9 4,361$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-6 Optimize Heat Exchanger Reset Schedule 2.4 5,099$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-7 Replace Leaking CHW Valve on AHU-11T 1.0 4,435$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-8 Fix Mixed Air Dampers to Improve Economizer 6.8 3,327$ $189,850


LAKESIDE 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement01.01 (d) Lighting Retrofit 21.8 6,142$ $133,865

LAKESIDE 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (d) Modify Mixed Air Temperature Control on AHU 1-10 0.7 39,119$

LAKESIDE 04.00 EMS (Energy Management System) and Controls04.13 Operational Enhancements 04.13 (d) Install Occupancy Sensors in Operating Rooms 5.9 19,448$ $143,500

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-1 Discharge Air Temperature Reset on AHU 1-10 0.2 218,688$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-2 Static Pressure Reset on AHU 1-8 1.2 25,736$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-3 Reconfigure Preheat Circulator Control on AHUs 1-10 34.1 817$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-4 Optimize HWST Reset 1.5 5,475$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-5 Replace AHU-4 Return Temperature Sensor 21.2 184$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-6 Replace Leaking CHW Valve on AHU-2 0.3 32,273$ $113,550


LRB 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement1.01 (e) Lighting Retrofit 2.4 127,030$

LRB 03.00 Electric Motors 03.00 Electric Motors 03.00 (e) Replace Cage Washer Pump Motors 91.9 125$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-1 EC Motors on Bio-Safety Cabinet Fans 28.6 5,841$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-2 EC Motors on DHW Circulators 11.5 3,522$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-3 EC Motors on AHU-10 & 11 5.3 3,120$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-4 Retrofit RO Water Pumps with VFDs 6.1 6,985$ $580,712

LRB 04.00 EMS (Energy Management System) and Controls04.02 Outside Air Control, and Economizers04.02 (e) Comparative Enthalpy Economizer on AHU-9 31.6 337$

LRB 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (e)-1 Scheduling and Set-points on AHU-9 Zones 7.5 5,306$

LRB 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (e)-2 Reprogram AHU-7 Preheat Control Sequence 0.2 62,976$

LRB 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (e)-3 Reduce Air Change Rates in Labs 8.1 84,109$

LRB 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (e)-4 Hot Water Loop Differential Pressure Reset 23.2 431$

LRB 04.00 EMS (Energy Management System) and Controls04.09 Re-Commission/Expand Existing BMS Controls04.09 (e)-5 Process CHW Loop Differential Pressure Reset 26.0 787$

LRB 04.00 EMS (Energy Management System) and Controls04.11 HVAC Modifications - Add New Systems04.11 (e)-1 Heat Recovery on Make-up Air Units (AHU 1-6) 5.7 174,743$

LRB 04.00 EMS (Energy Management System) and Controls04.11 HVAC Modifications - Add New Systems04.11 (e)-2 Install Passive Chilled Beams in Labs 20.8 89,734$ $3,631,748

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-1 Static Pressure Reset 1.4 39,718$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-2 Discharge Air Temperature Reset 0.4 48,365$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-3 Replace Leaking Preheat Valves 0.5 41,634$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-4 Replace Leaking Chilled Water Valve 1.0 10,363$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-5 Reduce AHU-9 Minimum Outdoor Air 0.5 16,818$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-6 Reprogram AHU-10, 11 Zone Temperature Set-points 5.4 716$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-7 Replace Preheat Face/Bypass Damper Actuators 0.2 59,754$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-8 Exhaust Fan Static Pressure Reset 0.3 21,392$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-9 Temperature Set-backs in Lab Corridors 1.7 11,782$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-10 Hot Water Supply Temperature Reset 0.2 42,940$ $160,175


SCHOOL 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement01.01 (f) Lighting Retrofit 15.0 79,942$

SCHOOL 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (f)-1 Retrofit FCU & FPB Fans With EC Motors 17.9 10,543$

SCHOOL 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (f)-2 Retrofit Enviro-Room Evap Fans with EC Motors 18.7 9,323$

SCHOOL 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (f)-1 Loading Dock Variable Exhaust Controls 2.3 31,793$

SCHOOL 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (f)-2 Reduce Lab Air Changes 3.3 242,044$

SCHOOL 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (f)-3 Install VFDs & CO2 Ventilation Controls on Library ACs 2.3 60,203$

SCHOOL 17.00 Unknown HVAC 17.09 Add Economizer Capabilities 17.09 (f) Reclaim Return Air on AC-12 5.3 7,442$

SCHOOL 21.00 Renewable Energy Systems 21.02 Solar Water Heating 21.02 (f) School Solar Hot Water 36.5 9,288$ $2,960,444

SCHOOL 04.00 EMS (Energy Management System) and Controls04.07 DDC Controllers 04.07 (f) Upgrade Terminal VAV Mixing Box Controls 20.8 87,919$ $1,827,525

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-1 Optimize Perimeter HW Reset 8.0 3,874$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-2 Auditorium Scheduling & Occupancy Controls 4.9 41,182$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-3 Repair Heating Valves & Actuators 0.7 79,206$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-4 Repair Cooling Valves & Actuators 1.7 10,656$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-5 Repair Economizer Dampers & Optimize Sequence 1.7 154,700$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-6 Air Sealing Repairs on AC Units 19.8 22,310$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-7 Optimize Static Pressure Reset 7.3 3,826$ $1,041,050


POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-1 Sherman Center Rooftop Photovoltaic Array 26.7 12,386$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-2 Quad Four Dual-Axis Tracker Photovoltaic Array 28.6 8,382$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-3 Plantation Hillside Fixed Tilt Photovoltaic Array 22.1 80,795$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-4 South Road Garage Canopy Photovoltaic Array 53.2 41,625$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-5 Plantation Street Garage Canopy Photovoltaic Array 53.9 77,739$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-6 First Road Garage Canopy Photovoltaic Array 52.6 144,770$ $16,369,277

POWER PLANT 04.00 EMS (Energy Management System) and Controls04.03 Variable Speed Drives 04.03 (g) Conversion to Variable Primary CHW Pumping 3.8 50,610$

POWER PLANT 04.00 EMS (Energy Management System) and Controls04.13 Operational Enhancements 04.13 (g) Coordinated Control of Primary & Tertiary Pumping 8.2 2,068$ $208,575


GRAND TOTALS 8.76 4,391,646$ 38,491,883$


ECMS BY MEASURE CATEGORY

BUILDING MEASURE CATEGORY MEASURE TYPE DESCRIPTION COST

ACC 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement 01.01 (a) Lighting Retrofit 116,710$

BENEDICT 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement 01.01 (b) Lighting Retrofit 110,150$

HOSPITAL 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement 01.01 (c) Lighting Retrofit 1,025,490$

LAKESIDE 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement 01.01 (d) Lighting Retrofit 133,865$

LRB 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement 01.01 (e) Lighting Retrofit 302,250$

SCHOOL 01.00 Lighting 01.01 Lamps, Ballasts and Fixtures Replacement 01.01 (f) Lighting Retrofit 1,197,300$

BENEDICT 02.00 Lighting Controls 02.01 Lighting Occupancy Sensors 02.01 (b) Install Occupancy Sensors 67,100$

LRB 03.00 Electric Motors 03.00 Electric Motors 03.00 (e) Replace Cage Washer Pump Motors 11,500$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-1 EC Motors on Bio-Safety Cabinet Fans 167,148$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-2 EC Motors on DHW Circulators 40,544$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-3 EC Motors on AHU-10 & 11 16,500$

LRB 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (e)-4 Retrofit RO Water Pumps with VFDs 42,770$

SCHOOL 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (f)-1 Retrofit FCU & FPB Fans With EC Motors 189,200$

SCHOOL 03.00 Electric Motors 03.01 High Efficiency Motors w/ VFDs 03.01 (f)-2 Retrofit Enviro-Room Evap Fans with EC Motors 174,400$

ACC 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (a)-1 Tighten Occupancy Schedules 30,625$

ACC 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (a)-2 Install New Occupancy Sensors for HVAC Control 708,110$

BENEDICT 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (b)-1 FCU Controls Upgrade 848,600$

BENEDICT 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (b)-2 HW Loop dP Reset 8,100$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.02 Outside Air Control, and Economizers 04.02 (c) Comparative Enthalpy Economizer on AHU-1L, 1R, 1T-7T 36,850$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (c)-1 Reconfigure Preheat Circulator Enable Sequence on AHU-1B-6B 11,400$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (c)-2 Reconfigure AHU-15T/16T Preheat Temperature Control 5,800$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (c)-3 Increase AHU-10T & 11T Minimum Discharge Set-point 5,800$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (c)-4 Hot Water Loop Differential Pressure Reset Schedule 12,000$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.11 HVAC Modifications - Add New Systems 04.11 (c) Reconfigure Preheat & Discharge Reset Schedules on AHU-1B-6B 120,700$

HOSPITAL 04.00 EMS (Energy Management System) and Controls 04.14 Exhaust Hood Occupancy Control 04.14 (c) Kitchen Hood Controls 184,800$

LAKESIDE 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (d) Modify Mixed Air Temperature Control on AHU 1-10 27,900$

LAKESIDE 04.00 EMS (Energy Management System) and Controls 04.13 Operational Enhancements 04.13 (d) Install Occupancy Sensors in Operating Rooms 115,600$

LRB 04.00 EMS (Energy Management System) and Controls 04.02 Outside Air Control, and Economizers 04.02 (e) Comparative Enthalpy Economizer on AHU-9 10,650$

LRB 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (e)-1 Scheduling and Set-points on AHU-9 Zones 39,650$

LRB 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (e)-2 Reprogram AHU-7 Preheat Control Sequence 10,000$

LRB 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (e)-3 Reduce Air Change Rates in Labs 682,450$

LRB 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (e)-4 Hot Water Loop Differential Pressure Reset 10,000$

LRB 04.00 EMS (Energy Management System) and Controls 04.09 Re-Commission/Expand Existing BMS Controls 04.09 (e)-5 Process CHW Loop Differential Pressure Reset 20,500$

LRB 04.00 EMS (Energy Management System) and Controls 04.11 HVAC Modifications - Add New Systems 04.11 (e)-1 Heat Recovery on Make-up Air Units (AHU 1-6) 995,504$

LRB 04.00 EMS (Energy Management System) and Controls 04.11 HVAC Modifications - Add New Systems 04.11 (e)-2 Install Passive Chilled Beams in Labs 1,862,993$

SCHOOL 04.00 EMS (Energy Management System) and Controls 04.07 DDC Controllers 04.07 (f) Upgrade Terminal VAV Mixing Box Controls 1,827,525$

POWER PLANT 04.00 EMS (Energy Management System) and Controls 04.03 Variable Speed Drives 04.03 (g) Conversion to Variable Primary CHW Pumping 191,575$

POWER PLANT 04.00 EMS (Energy Management System) and Controls 04.13 Operational Enhancements 04.13 (g) Coordinated Control of Primary & Tertiary Pumping 17,000$

ACC 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (a) Retrofit AHU-5 Supply Fan with VFD 23,000$

SCHOOL 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (f)-1 Loading Dock Variable Exhaust Controls 74,315$

SCHOOL 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (f)-2 Reduce Lab Air Changes 807,463$

SCHOOL 09.00 VFD's (Variable Frequency Drives) 09.00 VFD's 09.00 (f)-3 Install VFDs & CO2 Ventilation Controls on Library ACs 139,565$

BENEDICT 12.00 Window and Doors 12.04 Low-E Window Film 12.04 (b) Install Low-E Window Film 90,800$

HOSPITAL 17.00 Unknown HVAC 17.03 AHU: Repair/Replace CV with VAV 17.03 (c)-1 Complete VAV Conversion on AHU-1B-6B & 1T,2T,3T,4T,6T,7T 6,562,276$

SCHOOL 17.00 Unknown HVAC 17.09 Add Economizer Capabilities 17.09 (f) Reclaim Return Air on AC-12 39,600$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-1 Replace Weather Station 12,700$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-2 Calibrate Flow Stations & Reduce Unoccupied OA 35,100$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-3 Static Pressure Reset on AHUs 1-4 38,200$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-4 Reprogram Discharge Temperature Reset on AHUs 1-4 20,300$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-5 Reduce AHU-2 OA Damper Minimum Position 7,700$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-6 Calibrate Zone CO2 Sensors 52,200$

BUILDING MEASURE CATEGORY MEASURE TYPE DESCRIPTION COST

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-7 Replace AHU-4 Return Air CO2 Sensor 3,500$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-8 Reduce VAV Unoccupied Flow Set-points 389,900$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-9 Reprogram Zone Set-points & Implement Deadband 55,650$

ACC 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (a)-10 Reprogram Unoccupied Zone Temperature Control 8,613$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-1 Replace Preheat Valves & Actuators on AHU-1B-6B, 1T-7T 83,700$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-2 Lock-out Humidification & Calibrate Return Air %RH Sensors 38,200$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-3 Replace Leaking Preheat Valve on AHU-13T 5,000$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-4 Duct Static Pressure Reset on AHU-1R, 15T/16T 19,700$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-5 Adjust AHU-1L Temperature Control 4,100$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-6 Optimize Heat Exchanger Reset Schedule 12,000$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-7 Replace Leaking CHW Valve on AHU-11T 4,650$

HOSPITAL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (c)-8 Fix Mixed Air Dampers to Improve Economizer 22,500$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-1 Discharge Air Temperature Reset on AHU 1-10 33,700$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-2 Static Pressure Reset on AHU 1-8 31,700$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-3 Reconfigure Preheat Circulator Control on AHUs 1-10 27,900$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-4 Optimize HWST Reset 8,200$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-5 Replace AHU-4 Return Temperature Sensor 3,900$

LAKESIDE 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (d)-6 Replace Leaking CHW Valve on AHU-2 8,150$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-1 Static Pressure Reset 54,000$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-2 Discharge Air Temperature Reset 17,200$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-3 Replace Leaking Preheat Valves 19,050$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-4 Replace Leaking Chilled Water Valve 10,425$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-5 Reduce AHU-9 Minimum Outdoor Air 8,500$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-6 Reprogram AHU-10, 11 Zone Temperature Set-points 3,900$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-7 Replace Preheat Face/Bypass Damper Actuators 14,400$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-8 Exhaust Fan Static Pressure Reset 6,600$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-9 Temperature Set-backs in Lab Corridors 19,500$

LRB 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (e)-10 Hot Water Supply Temperature Reset 6,600$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-1 Optimize Perimeter HW Reset 31,000$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-2 Auditorium Scheduling & Occupancy Controls 202,950$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-3 Repair Heating Valves & Actuators 59,050$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-4 Repair Cooling Valves & Actuators 18,250$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-5 Repair Economizer Dampers & Optimize Sequence 259,900$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-6 Air Sealing Repairs on AC Units 442,100$

SCHOOL 18.00 Retro-Commissioning 18.00 Retro Commissioning 18.00 (f)-7 Optimize Static Pressure Reset 27,800$

HOSPITAL 21.00 Renewable Energy Systems 21.02 Solar Water Heating 21.02 (d) Hospital Solar Hot Water 539,439$

SCHOOL 21.00 Renewable Energy Systems 21.02 Solar Water Heating 21.02 (f) School Solar Hot Water 338,601$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-1 Sherman Center Rooftop Photovoltaic Array 331,294$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-2 Quad Four Dual-Axis Tracker Photovoltaic Array 239,904$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-3 Plantation Hillside Fixed Tilt Photovoltaic Array 1,783,939$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-4 South Road Garage Canopy Photovoltaic Array 2,214,300$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-5 Plantation Street Garage Canopy Photovoltaic Array 4,187,040$

POWER PLANT 21.00 Renewable Energy Systems 21.01 Photovoltaic Modules 21.01 (g)-6 First Road Garage Canopy Photovoltaic Array 7,612,800$

TOTALS 38,491,883$

457 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Solar Hot Water Report

SOLAR HOT WATER REPORT

Solar Hot Water Heating:Hospital & School Systems

University of Massachusetts Medical Center

55 Lake Ave North, Worcester, MA, 01655

Prepared by:

July 18, 2012

BEAM Energy & Engineering

Chris Beebe, PEJennifer Taylor

Customer Presentation Outline

1. Solar Heating Overview

2. Current Usage Conditions

3. Equipment & Design - School Building System

4. Equipment & Design - Hospital Building

5. Energy Production, Benefits

6. System Costing & Financials

7. Construction Conditions

8. Maintenance and M&V

Prepared by: BEAM Energy & Engineering, www.beamgrp.com

Solar Heating Overview

MA Solar Heating Industry &BEAM

• Residential: Started in May 2011, BEAM is technical consultant to MassCEC.

• Commercial: Starting in May 2011, LEAN/ABCD Solar Thermal Program funded in 19commercial scale project. This program has been renewed for FY 2012 and ananticipated 16 more projects will be built. BEAM conducts all design, bidding, and M&Vfor these projects for LEAN/ABCD.

• Commercial Feasibility Studies: Starting in May 2011, The MassCEC CommonwealthSolar Hot Water Pilot Program funded 41 pre-construction feasibility studies. BEAM hasapproximately 20,100,000 therms of customer usage through Program, all othersprojects total approximately 1,876,000 therms.

• The Commonwealth Solar Hot Water Program has recently been approved for a $10million program that started July 2012 and will run 4.5 years to fund residential /commercial projects and commercial studies.

Overview

• Collector• Storage tank• Pumps, Piping, Valves• Heat exchangers• Control Unit• Freeze Protection• Stagnation Protection• Auxiliary Heat Source• Monitoring Unit

Applications

•Domestic hot water (Residential,hospitals, universities, correctioncenters, hotels, restaurants, etc.)

•Process hot water (Laundromats,food processing, boiler makeup /feed-water heating)

•Solar pool heating (schools,community centers, gyms)

•Space heating (radiant, pre-heat,HVAC air heating)

•Solar assisted cooling (absorptionchiller)

Solar Fuel Resource•TW =Terawatt =1012 watts

•Total powerused byhumansworld widein 2006 was16 TW2

2. www.wikipedia.org

Why Go Solar?

ns

1. Energy security. The sun provides enough energy in one minute to fuel theworld for one year. The amount of solar energy striking the earth over athree day period is equivalent to all of the stored energy in fossil energysources. 1

2. Massachusetts Global Warming Solutions Act (GWSA) of 2008: Reduce GHG emissions 10-25% below statewide 1990 levels by 2020 80% below statewide 1990 emissions by 2050. One goal of the MA Clean Energy and Climate Plan for 2020 is

developing a mature market for solar thermal water and spaceheating.

3. It’s free, easy to access, and inexhaustible.4. Risk Mitigation - Solar energy doesn’t have price fluctuations5. Solar energy doesn’t depend on politics or country to country relationships6. Solar energy does reduce harmful health and environmental emissio Solar energy is marketable for healthy living

Collector Technologies

• Unglazed Collector

• Flat Plate

• Evacuated Tube

• Concentrating Solar Collector

• Solar Air Heating

Glazed Flat Plate CollectorCost:

$90-$200/ft2

Temperatures:85°F to 160°F

Typical Applications:DHW Heating

Radiant Floor Space Heating

Pros

Proven technology

Long term functionality

High aperture area (0.97)

Cons

Temperature limitations – efficiency drop at high temperatures

Evacuated Tube Collector

Cost:$130-$250/ft2

Temperatures:Up to 300°F

Typical Applications:DHWLow-temp IndustrialSpace Heating

ProsHigher temperature than flat plateImproved efficiency at higher operating temperaturesPipe bursting due to freezing is not such a concern as it is with flat plates

ConsVacuum may be lost over time – efficiency lostSlightly higher initial cost vs. flat plateSmaller aperture area (0.72)

Storage Tank

• Acts as a battery to hold thesystem’s heat

• Up to 6,000 gallons +

• Size depends on desired storagelength and usage patterns

• Constant usage facilities: small sizerequirement

• Daily spikes in water usage: largetank size requirement to storeenough heat for daily spike

• Above or underground storage

• Insulation

Other System Components

• Heat exchangers: Single or double walled depending on fluidcomposition and pressure

• Controls: Turn pumps on to activate the system whencollector temperature exceeds tank temperature, and turnpumps off when collectors temperature falls. Variable speeddrive controls save electricity

• Pumps, Piping, & fitting: Minimize pipe lengths to minimizeheat loss.

• Insulation – Prevents solar heat from escaping to ambientsurroundings

• Auxiliary heat source: Existing fuel source

Overheating & FreezeProtection

Stagnation is the condition in which heat transfer fluid boils off inthe collector, due to prolonged solar exposure with no coolingflow. If Glycol is the heat transfer fluid, it can degrade to glycolicacid which has no freeze protection properties and can degradesystem components.

Freeze Protection - Indirect Forced Circulation(Closed Loop)

• Active closed loop glycol

• Closed loop drainback

System Design

Factors For a Successful Solar ThermalInstallation:

1. Large, consistent demand for hot water2. Structural analysis of building by a structural engineer3. High energy costs4. Energy modeling before installation to protect against

system oversizing / undersizing.5. Strong environmental interest of building

owner/operator6. Site location conducive to installation (i.e. collector

location near integration point, short / direct pipingruns, room for easily accessible storage, etc.).

UMass Med Center – 3D Model

Satellite Photo BEAM 3D Model

Po

un

ds

of

Stea

m

Current Steam Costs & Usage –Hospital & School

20,000,000

16,000,000

Steam Breakdown

12,000,000

8,000,000

4,000,000

0

Jan-11 Feb-11 Mar-11 Apr-11 May-11 Jun-11 Jul-11 Aug-11 Sep-11 Oct-11 Nov-11 Dec-11

Month

Steam Generation Costs

Jan ‘11 Feb ‘11 Mar ‘11 Apr ‘11 May ‘11 June ‘11 July ‘11 Aug ‘11 Sept ‘11 Oct ‘11 Nov ‘11 Dec ‘11

Steam

Generated1,179,880 1,034,923 1,004,979 870,277 1,013,209 1,049,264 1,272,345 1,216,470 1,122,207 987,755 972,295 980,811

Hospital

50#152,115 132,523 130,810 101,001 82,404 75,967 75,016 75,965 75,648 91,111 98,354 120,143

School 50# 233,168 216,783 153,986 121,381 72,061 46,223 36,126 40,055 64,359 97,414 123,763 104,393

Table: $/ month on steam usage in $. ($/lb of steam = .011911)

School Hot Water UsageG

allo

ns

Pe

rM

inu

te

Hot water usage: Average of 5,483 gallons per day

70

60

50

40

30

20

10

0

0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00

Time of Day


Hospital Hot Water UsageG

allo

ns

Pe

rM

inu

te(G

PM

)

Hot water usage: Average of 3,540 gallons per day (Hot Water Monitoring Data conducted by UMass Med staff)

30

25

20

15

10

5

0

0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00 12:00 0:00

Time of DayHot Water Uses

• Licensed Beds: 781 (plus 69 bassinets)• Active Medical Staff: 1,327• Registered Nurses: 2,409• Employees: 10,695

• Births: 4,115• Hospital Admissions: 42,400• Emergency Department Visits: 140,915• Ambulatory Department Visits: 864,664• Approximately 1,000 students annually

Equipment & Layout

School Project


School Building System Integration PipingDiagram

Collector array

Collector Array: Glazed flat plate; 4,045 ft2

Installation: 35° inclination; south facingCold water in

Check valve

Bypass valve

Recirculation/ emergencyshower loop

Target Load: DHW -Bathroom, Showers

GPD: 5,500

Existing shell andtube heat

Thermostatic mixingvalve

To DHW fixtures

exchanger Equipment Location: B-Level Mechanical Room

School Building Equipment Location: B-Level Mechanical Room

Primary Heat Exchanger to TargetLocation in Mechanical Room for Buffer

Tank, Controls, Heat Exchangers

School


Collector Layout School Building

School Building

-Distance between collector and edges: 10’

-Arrow shows B-Level Mechanical Rm -where tank, heat exchangers, and controls willbe located will be located

-Individual bank length: 24’

Hospital Project


Hospital Building System Integration PipingDiagram

Collector array

Collector Array: Glazed flat plate; 2,697 ft2 (96 7x4’s)

Installation: 35° inclination; south facing

Check valve Typical Warranties

-10 year warranty on the collectors;

-2 year warranty for other components;

-Comprehensive 2 year installation/labor warranty.

Target Load: Showers,Bathroom, Kitchen/café, 3,500GPD

Thermostaticmixing valve

2,700 gallonbuffer tank

Existing shell andtube heat exchanger

Bypass valve

To DHW fixtures

Equipment Location: 9th Floor Mechanical Room

9thHospital Building Equipment Location:Floor Mechanical Room

Location in Mechanical Room for Buffer Tank,Controls, Heat Exchangers

Note: One of the 1,980gallon DHW tanks isdecommissioned andcould potentially be usedas the solar buffer tank. Ifnot, ample open spaceexists.

Collector Layout Hospital Building

Hospital Building

-Distance between collector and roofedges: 10’

-Arrow shows 9th Floor Mechanical Rmwhere tank, heat exchangers, and controlswill be located

-Individual bank length: 32’

-96 total collectors - twelve rows of 8

System Performance - Both


School Hospital

Installed Collector Power 898 kBtu/hr 598kBtu/hr

Irradiation onto Collector 2

Surface508 kBtu/ft Annually 508kBtu/ft2 Annually

Energy Delivered by the 2

Collectors218 kBtu/ft annually 229kBtu/ft2 annually

System Efficiency 41% 44%

Solar Fraction 58% 61%


School

Solar Fraction

Hospital

Yellow= solar contribution: 580,899 kBtu

Orange = Total energy consumption 948,939 kBtu

Yellow= solar contribution: 838,270 kBtu

Orange = Total energy consumption1,439,714 kBtu

Costing & Financials


Energy and Emissions

Hospital School

Energy Savings• 10,199 therms / yr

• 305,970 therms / lifetime

• 19,854 therms / yr

• 576,300 therms / lifetime

Cost Savings• $13,598 / yr

• $646,933

• $30,592 / yr

• $1,437,824

Annual Pollution

Reduction

•100,305 lbs CO2

•128 lbs NOx annually

•200,377 lbs CO2

•257 lbs NOx annually


Typical Costs

• Eliminate missedcomponents• Can compare andunderstand bids moreeasily• Allows for independentcomponent cost analysis• Nearly eliminates changeorders


Costs

• Average Flat Plate Hot Water System - $158/ft2• School - $133/ft2• Hospital - $123/ft2 Prepared by: BEAM Energy & Engineering, www.beamgrp.com

Cost

Hospital School

Cost of System $539,439 $338,601

MassCEC Incentive $30,000 $30,000

LBE TBD TBD

Total Cost $509,439 $308,601

Simple Payback 13.8 years 14.1 years


Other Potential Incentives

School Hospital

Incentives

1. Tax incentives if the university can take advantage of

them

a. Federal Investment Tax Credit: 30% after grants.

b. Modified Accelerated Cost Recovery System:

Approx. 26.5%

ITC $152,832 $92,580

MACRS $132,454 $81,779


Construction


Construction Logistics

Project Prep Intake Description

Utilities Available For Contractor: Public building available to the contractor.:- Source of Temp Utilities Shut down Procedures Require # day notice and detail of how it- Facilities Available On Site will affect the building occupants. Any shutdowns must be- Shutdown Procedures operational by the end of the day

Traffic – Crane Logistics Delivery Traffic and Site Loading requires # day notice anddetail of how it will affect the building occupants.Location:

Parking Location Onsite:

Work Days and Hours Work Days:Work Hours: TBD am allowed on-site, noise allowed TBD am toTBD pm.

Ingress and Egress To Site:

Owner’s Expectations Safety, On-time Delivery, language, and HousekeepingOther:

Real-Time Internet PerformanceMonitoring

• Data stored on server•Know how much heatthe system is producing•Alerts if systemmalfunctions

etc). Automated email alerts can be set up.

Maintenance and PersonnelRequirements

Annual glycol check with a refractometer. Estimated glycol exchanging every 5 years

Visual check for the collectors, piping, and tank for leaks, stains, broken glass.

Monitoring units send notifications if the system malfunctions (Pressure drop,broken valve,

Summary

Substantial Reduction in water heating costs

Carbon goals may be unattainable without solar fuel and heatingtechnologies

Both Hospital and School are excellent applications due to highwater usage, year round loading, and favorable siting conditions

Potentially apply for LBE grant to help offset cost

MassCEC just started new commercial grant program

458 DCAMM UMMC Worcester, MA | AL2 Energy Audit | Renewables Report

RENEWABLE ENERGY TECHNOLOGY REPORT

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