retrocommissioning lessons from the field by eveline killian
DESCRIPTION
Retrocommissioning has multi-faceted benefits – operating, maintenance and replacement cost reductions – but its value is still hard to market to building owners and energy utilities. This presentation details a number of successful retrocommissioning projects in Vermont with proven energy and maintenance savings. It also details an innovative consulting contract Cx Associates has structured to maintain the energy savings realized through retrocommissioning, as well as help control maintenance costs and identify further opportunities. Building owners and efficiency utilities are convinced by the facts of real savings – come listen to some examples! Success stories include a 70,000 square foot, 100-year old, 4-story brick building with office and retail spaces with a improvements made to its central heat pump system; a 42,000 square foot public library with BMS control upgrades, and a 2-story office building with a central hydronic heating system and rooftop unit cooling systems. Improvements range from simple maintenance items to VFD retrofits to BMS installations. We will detail the audit and analysis we performed to gain commitment from both the building owner and the energy utility, the design process, the actual construction trials and tribulations, and methods of proving the savings outcome. The projects have been in operation for a minimum of nine months and we will discuss their ongoing performance. Real-life examples of the system and human issues we encountered in these older buildings, and the collaboration it took to overcome them, will be described. In addition, we have entered an “Operational Performance” contract with one of our retrocommissioned buildings. This contract oversees the preventative maintenance program to ascertain its effectiveness, provides technical support for maintenance issues, monitors energy saving retention, ensures efficient operation of the HVAC systems, and identifies further opportunities. In this presentation we will discuss the process, successes and challenges of such an innovative program.TRANSCRIPT
Retrocommissioning Lessons from the Field
Eveline Killian, CEMCx Associates, LLC
AIA Quality Assurance
The Building Commissioning Association is a Registered Provider with The American Institute of Architects Continuing Education Systems (AIA/CES). Credit(s) earned on completion of this program will be reported to AIA/CES for AIA members. Certificates of the Completion for both AIA members and non-AIA members are available upon request.
This program is registered with AIA/CES for continuing professional education. As such, it does not include content that may be deemed or construed to be an approval or endorsement by the AIA of any material of construction or any method or manner of handling, using, distributing, or dealing in any material or product.
Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation.
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At the end of this session participants will be able to:
See the benefits of: • Retrocommissioning small commercial buildings• Developing a collaborative team • Staying flexible with expectations• Choosing the measures carefully
And…be forewarned of some stumbling blocks
Learning Objectives
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Presentation OverviewExample Projects
Lessons Learned
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Howard Opera House
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Problem Statement
• Constant speed pumps
• Manual diverter valve
• Failing controls
• Open ductwork to MEP
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RCx Solutions
• VSDs on cooling tower and main pumps
• Removal of diverter valve
• Boiler circulating pump
• Central Plant controls
• Controlled OA dampers
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Realized Savings
-
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000A
pr-1
3
May
-13
Jun-
13
Jul-1
3
Aug
-13
Sep
-13
Oct
-13
Nov
-13
Dec
-13
Jan-
14
Feb-
14
Mar
-14
kWh
Pre- and Post-Installation Monthly kWh
Pre kWh Post kWh
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Fletcher Free Library
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Controls Upgrade Savings
Average annual utility bill savings of 18%.
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Operational Performance Support Services Contract
• Monitor HVAC system operation & utility bills
• Maintenance program definition & oversight
• Assessment of unplanned maintenance items
• Further energy savings identification
• Long-term capital planning for HVAC system costs
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Performance Monitoring Successes
• Chiller compressor failure Early cooling tower failure warning.
• HVAC-1 economizer/fan speed control.
• Exhaust fan failure discoveries.
• Resolution of draft issues at circulation desk.
• Freezestat failure discoveries.
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Typical RCx Measures
• VSDs on pumps
• Controls
• Setpoint changes
• Pipe insulation
• Economizer
• System harmonizing
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Stumbling Blocks• Scope increases during
project• Narrow our attention…
and then… refer to firstbullet
• Contractor schedule pushed out
• Plans were incomplete, took long to piece together
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What Went Right
The people!• Quality
contractors
• Flexible team
• Collaborative team
• Good communication
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Lessons Learned
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Lesson #1: Gauge the OwnerDetermine:
• their version of the problem
• their openness to new efficiency ideas
• if there are others who could influence the project and involve them early
Hear and address their concerns immediately
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Lesson #2: Good Contractors
Create a team you can trust and then listen to their ideas throughout the project
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Lesson #3: Stay FlexibleIf it’s an old building, things WILL come up unexpectedly – stay flexible and creative, and convey this mindset to the owner.
HoweverDon’t necessarily promote this attitude to the contractors – you’ll be bombarded with suggestions and change orders!
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Lesson #4: Choose Measures Wisely
• Present at least two tiers in the proposal:• Tier 1: conservative approach
that addresses their concerns • Tier 2: deeper cost-effective
opportunities• Tier 3: long term opportunities
• Don’t push – they’ll balk
• Don’t try to do it all – they’ll balk
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Lesson #5: Choose Owners Wisely
If you can, pick owners that:• care about their
building, not just their bottom line
• have the support they need to make it happen
• will potentially lead to more projects
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Why It’s Worth Doing
• Commercial Buildings consume nearly 20% of all energy used in the United States.
• We spend more than $200 billion each year to power our country's commercial buildings.
• “A typical commercial building could save 20% on its energy bills simply by commissioning existing systems so they operate as intended.”
Source: U.S. DOE - http://www4.eere.energy.gov/alliance/node/9