building energy efficiencybuilding energy efficiency · and leed® energy and atmosphere credits...

ASHRAE University of Illinois Student ChapterApril 20, 2011

Building Energy EfficiencyBuilding Energy Efficiencyand LEED® Energy and Atmosphere Credits

Jean Ascoli, LEED AP BD+C Architect, Energy Specialist

Building Research Council, SEDACBuilding Research Council, SEDACSchool of Architecture

University of Illinois at Urbana-Champaign

Energy and AtmosphereEnergy and AtmosphereWhy focus on energy?• Generating energy from fossil fuels negatively affects

the environment at each step, including:Extraction TransportationExtraction RefiningConsumption

TransportationDistribution Waste Disposalp

Why the focus on buildings?• In the U.S. Buildings consume approximately

39% of the Total Energy produced annually74% f th El t i it d d ll74% of the Electricity produced annually

Where does LEED come in?Where does LEED come in?

For today we’ll focus on:For today we ll focus on:

LEED NC-2009

Regional Priority

4 PossibleLEED NC 20091 Prerequisite26 Possible Points

PointsLEED NC 20098 Prerequisites &110 Possible Points 26 Possible Points110 Possible Points

1 Prerequisite2 P i it q10 Possible Points2 Prerequisites

15 Possible Points

3 Prerequisites35 Possible Points

1 Prerequisite14 Possible Points 35 Possible Points14 Possible Points

Innovation In Design 6 Possible Points

Energy and AtmosphereLEED NC 2009 EAEnergy and Atmosphere

3 Prerequisites35 P ibl P i t35 Possible Points

Energy and AtmosphereEnergy and AtmosphereWhat does the LEED® EA Category Cover?• Energy Performance• Commissioning• On-Site Renewable Energy• On-Site Renewable Energy• Refrigerant Choice• Measurement and Verification• Green Power

Energy and AtmosphereEnergy and AtmosphereToday we’ll focus on three aspects of LEED® EA:• Energy Performance• Commissioning• On-Site Renewable Energy• On-Site Renewable Energy• Refrigerant Choice• Measurement and Verification• Green Power

Why these?• “An ounce of prevention is worth a pound of cure.”• Also, if we actually reduce consumption enough,

renewable energy and green power become muchrenewable energy and green power become much more cost effective; and you reduce the amount of refrigerant needed, thus reducing its potential impact.

EA Best Practice ConceptsBuilding Energy Performance: Building energy

i i i fl d b h d i i

EA Best Practice Concepts

consumption is influenced by the design, construction, and maintenance of many complex elements including:• Building EnvelopeBuilding Envelope• Lighting• Heating, Ventilation, and Air conditioning (HVAC)• Domestic Water Heating• Building Schedules and Controls• Equipment Purchasing Policy (Plug Loads)• Equipment Purchasing Policy (Plug Loads)• Initial and Ongoing Commissioning• Maintenance Policies and Procedures• Occupant Training and Behavior

EA Best Practice ConceptsEA Best Practice ConceptsIntegrated Design, Construction, Commissioning and Operation: Understanding the relationships between all these different elements is key. Things to consider include:consider include:• The influence of envelope design on occupant comfort,

HVAC system sizing and controllability;• The impact of construction sequencing and methods on

the continuity of insulation layers, air barriers, lighting and HVAC systems controls etc ;and HVAC systems controls, etc.;

• The value of whole building commissioning to ensure all elements function as designed, and work together;

• The value of enhanced building owner staff training to ensure ongoing energy efficient operations.

EA Best Practice ConceptsEA Best Practice ConceptsIntegrated Design, Construction, Commissioning and Operation: • Design, construction, and operation must be consistent.• Review submittals to ensure conformance to all• Review submittals to ensure conformance to all

performance specifications related to EA.• Specify and observe construction site practices.p y p• Commissioning with enhanced owner/operator training

is essential.Need for meticulous follow through in the whole• Need for meticulous follow-through in the whole process.

EA in LEED NC 2009EA in LEED NC 2009LEED EA Prerequisite 1:

Fundamental Commissioning of Building Energy SystemsINTENT• Verify that energy-related systems are installed• Verify that energy-related systems are installed,

calibrated and perform according to owner’s project requirements, basis of design, and documents (CDs).

REQUIREMENTS• Designate an independent commissioning authority (CxA)• Document owner’s project requirements• Document owner s project requirements• Incorporate commissioning requirements into CDs• Implement a commissioning planp g p• Verify installation and performance of systems in Cx Plan• Complete summary report


Fundamental Commissioning of Building Energy SystemsREQUIREMENTS (cont.)• Minimum systems to be commissioned:• Minimum systems to be commissioned:

Heating, ventilating, air conditioning and refrigeration (HVAC&R) systems (mechanical and passive) and associated controls.

Lighting and daylighting controls.Domestic hot water systemsDomestic hot water systemsRenewable energy systems


Fundamental Commissioning of Building Energy SystemsREQUIREMENTS (cont.)• Additional potential systems for Cx (not mandatory):• Additional potential systems for Cx (not mandatory):

Building envelope.Storm water management systems.Water treatment systemsInformation technology systems


Fundamental Commissioning of Building Energy SystemsIMPLEMENTATION • Tasks and responsibilities:• Tasks and responsibilities:

Designate commissioning authority - EARLY.Document owner’s project requirements (OPR).Review OPR and basis of designDevelop and implement commissioning plan (Cx Plan)Incorporate requirements in CDsIncorporate requirements in CDsCommissioning design review (Only for Cx EA Cr. 3)Contractor submittal review (Only for Cx EA Cr. 3)( y )Verify installation and performance of commissioned

systems


Fundamental Commissioning of Building Energy SystemsIMPLEMENTATION (cont.)

Tasks and responsibilities:Tasks and responsibilities:Develop systems manual for commissioned systems

(Only for Cx EA Cr. 3).Verify that requirements for training are completed (Only

for Cx EA Cr. 3)Complete summary commissioning reportComplete summary commissioning report.Review building operation within 10 months after

substantial completion (Only for Cx EA Cr. 3)


Minimum Energy PerformanceINTENT• To establish the minimum level of energy efficiency for• To establish the minimum level of energy efficiency for

the proposed building and systems to reduce the environmental and economic impacts associated with excessive energy use.

REQUIREMENTS• Demonstrate a 10% improvement in the proposed• Demonstrate a 10% improvement in the proposed

building energy performance rating for new buildings (5% for major renovations to existing buildings), compared with the baseline building energy performance rating.


Minimum Energy PerformanceREQUIREMENTS (cont.)• Option 1: Calculate the baseline building energy• Option 1: Calculate the baseline building energy

performance rating according to the method in Appendix G, ASHRAE Standard 90.1 – 2007 using a computer simulation model for the whole building project.

• Option 2: Certain projects with relatively low square footage can follow the Prescriptive Compliance Pathfootage can follow the Prescriptive Compliance Path, using the ASHRAE Advanced Energy Design Guides. These include: Office and Retail Buildings < 20,000 sf; W h S lf St B ildi 50 000 fWarehouse or Self Storage Buildings <50,000 sf; Schools <200,000 sf.


Minimum Energy PerformanceREQUIREMENTS (cont.)• Option 3: Buildings complying with Sections 1 and 2 of• Option 3: Buildings complying with Sections 1 and 2 of

the Advanced Buildings™ Core Performance™ Guide, and which are <100,000 sf can follow this alternative Prescriptive Compliance Path.

• Schools Only: Must also establish an energy performance rating goal for the facility design usingperformance rating goal for the facility design using EPA’s ENERGY STAR® Target Finder rating tool.


Minimum Energy PerformanceIMPLEMENTATION • ASHRAE 90 1 2007 Appendix G Energy Modeling:• ASHRAE 90.1 2007 Appendix G Energy Modeling:

Determine Project Climate Zone


Minimum Energy PerformanceIMPLEMENTATION (cont.)• ASHRAE 90 1 2007 Appendix G Energy Modeling:• ASHRAE 90.1 2007 Appendix G Energy Modeling:

Baseline elements prescribed by App. G:Building envelope construction type and min.

performanceHVAC baseline systems



Baseline and proposed models both the same for:Building Configuration (number of stories, floor plans)Space Use ClassificationSchedules



Baseline and proposed models thermal performance adjusted for:

RoofsWalls (above and below grade)Exposed FloorsExposed FloorsSlab-on-Grade FloorsOpaque Doorsp qVertical Glazing (windows, curtainwalls, doors, etc.)Skylights



Baseline and proposed models both the same for:Thermal blocks (zoning)Receptacle and Other Loads

(25% of baseline cost per LEED)



Baseline and proposed models energy performance adjusted for:

LightingHVAC SystemsService Hot Water SystemsService Hot-Water Systems

EA in LEED NC 2009EA in LEED NC 2009LEED EA Credit 1:

Optimize Energy PerformanceINTENT• To achieve increasing levels of energy performance• To achieve increasing levels of energy performance

beyond the prerequisite standard to reduce the environmental and economic impacts associated with excessive energy use.

REQUIREMENTS• Demonstrate improvement in the proposed building• Demonstrate improvement in the proposed building

energy performance rating beyond the prerequisite minimums compared with the baseline building energy performance rating.


Optimize Energy Performance (1-19 Possible Points)REQUIREMENTS (cont.)• Option 1: Whole Building Energy Simulation following• Option 1: Whole Building Energy Simulation following

ASHRAE 90.1 2007 Appendix G Performance Rating Method. (1-19 points for NC and Schools).

• Option 2: Certain projects with relatively low square footage can follow the Prescriptive Compliance Path, -see EA Prerequisite 2 Option 2 (1 Point only)see EA Prerequisite 2, Option 2. (1 Point only)

• Option 3: : Buildings complying with Sections 1 and 2 of the Advanced Buildings™ Core Performance™ Guide - see EA Prerequisite 2, Option 3. (1 Point only)


Optimize Energy PerformanceREQUIREMENTS (cont.) Option 1: 1-19 Points awarded based on % improvement over baseline:based on % improvement over baseline:


Optimize Energy PerformanceIMPLEMENTATION• Energy Standard Requirements Addressed by• Energy Standard Requirements Addressed by

ASHRAE 90.1-2007: Envelope, HVAC&R, Service water heating (including swimming pools), Power (including all building power distribution systems), Lighting (including exit signs, building exterior, grounds, and parking garages), Other equipment (including all permanentlygarages), Other equipment (including all permanently wired electrical motors).

• All options: LEED ® gives credit for designed (modeled i ti ) for prescriptive) energy performance.


Enhanced Commissioning (2 Possible Points)INTENT• To begin the commissioning process early in the design• To begin the commissioning process early in the design

process and execute additional activities after systems performance verification is completed.

REQUIREMENTS (in addition to PR 1)• Have CxA on board prior to start of the construction

documents phasedocuments phase.• CxA must be completely independent of design and

construction work.• Commissioning design document review – prior to the

mid-construction documents phase.


Enhanced CommissioningREQUIREMENTS (in addition to PR 1) (cont.)• Contractor submittal review• Contractor submittal review• Develop systems manual for commissioned systems• Verify that requirements for training are completed• Review building operation within 10 months after

substantial completion


Measurement and Verification (2-3 Possible Points)INTENT• To provide for the ongoing accountability of building• To provide for the ongoing accountability of building

energy consumption over time.REQUIREMENTS• Option 1: Develop and implement a measurement and

verification (M&V) plan consistent with Option D: Calibrated Simulation (savings Estimation Method 2) asCalibrated Simulation (savings Estimation Method 2) as specified in the International Performance Measurement & Verification Protocol (IPMVP) Vol. III.


Measurement and Verification (2-3 Possible Points)REQUIREMENTS (cont.)• Option 2: Develop and implement a measurement and• Option 2: Develop and implement a measurement and

verification (M&V) plan consistent with Option B: Energy Conservation Measure Isolation, as specified in the IPMVP Vol. III.

• Both Options 1 & 2: Must implement for at least 1 year of post-construction occupancy Include a process forpost construction occupancy. Include a process for corrective action if the results of M&V indicate that energy savings are not being achieved.

LEED Certification

I t f P f

LEED Certification Does it Result in Energy Efficient Buildings?

Importance of Performance• While good design is important, performance is

essentialessential.• Environment and wallet are impacted by actual

performance, not design.• Recent criticisms of LEED building performance• New Building Institute – “Energy Performance of

LEED for New Construction Buildings” releasedLEED for New Construction Buildings released March ’08.

• Requested data from LEED certified buildings and analyzed actual usage against model and average building stock.

LEED-NC vs CBECS* EUILEED-NC vs CBECS EUI

Some LEED buildings are performing better than the averageSome LEED buildings are performing better than the average existing building stock (with lower energy use intensities – EUI)*Commercial Building Energy Consumption Survey (CBECS) from the U.S. Energy Information Administration,

EUI by EA Credit1 Points EUI by EA Credit1 Points All Building Types Office Buildings

Although the ranges in performance is large, actual energy use intensity (EUI) does decrease with more EA Credit 1 points.

Measured vs Proposed Measured vs Proposed Savings Percentages and EUIs

Proposed savings averaged 25%, measured savings averaged 28% Many buildings met anticipated consumption levels28%. Many buildings met anticipated consumption levels, some exceeded expectations, while others failed to meet them.

Measured Savings and CreditsMeasured Savings and CreditsEA Cr. 3 EA Cr. 5 IEQ Cr.8.1 IEQ Cr.8.2

Enhanced Cx M&V Daylighting Viewsy g g

Achievement of credits does not ensure increased savings.

Possible ReasonsPossible ReasonsModeling vs. Performance• Models are built on assumptions

Usage levels/schedules may changeBehavioral impacts (thermostats lights etc)Behavioral impacts (thermostats, lights, etc)Systems modeled as perfect/functional

• ImplementationA i i i i d dAggressive commissioning neededWeatherization (air barrier) important – difficult to

predict and model accuratelyp y• More complicated buildings

Advanced controlsComplex schedulesComplex schedules

Building Energy Efficiency Building Energy Efficiency and LEED® EA CreditsSummary / Conclusions• On the whole, measured performance of LEED buildings

b tt th th CBECS d ti i t d l lbetter than the CBECS averages and anticipated levels.• But a significant portion of LEED buildings are not

performing up to expectations.performing up to expectations.• Corrective actions needed

Better, more realistic modeled assumptionsMore aggressive commissioning and M&VSustained operation must emphasize energyKnowledgeable and assertive usersKnowledgeable and assertive users

LEED InfluenceLEED Influence• New LEED projects must submit 5 years of

performance – this will be valuable dataperformance – this will be valuable data.• Need to ask how non-LEED buildings compare in

their proposed to measured performance?• LEED helps argument for verification, gives

building better chance to succeed• LEED is not solely about energy efficiency:• LEED is not solely about energy efficiency:

EA Case StudiesEA Case StudiesUniversity of Illinois Business Instructional Facility• Owner’s Re-Commissioning.

Normal Children’s Discover Museum• SEDAC Energy Audit.S C e gy ud• SEDAC Re- (? Retro-) Commissioning.

Energy and AtmosphereEnergy and AtmosphereWhat does SEDAC do?• Promote Efficient Use of Energy Resources • Provide Free Advice and Analyses

Make Recommendations for• Make Recommendations for Intelligent Building Design and OperationsEfficient Building Components and Systems g p y

Thank you!Thank [email protected]

building energy efficiencybuilding energy efficiency · and leed® energy and atmosphere credits...

Documents