and LEED Energy and Atmosphere Credits Jean Ascoli, LEED AP BD+C Architect, Energy Specialist

Transcription

1 ASHRAE University of Illinois Student Chapter April 20, 2011 Building Energy Efficiency and LEED Energy and Atmosphere Credits Jean Ascoli, LEED AP BD+C Architect, Energy Specialist Building Research Council, SEDAC School of Architecture University of Illinois at Urbana-Champaign

2 Energy and Atmosphere Why focus on energy? Generating energy from fossil fuels negatively affects the environment at each step, including: Extraction Transportation Refining Distribution Consumption Waste Disposal Why the focus on buildings? In the U.S. Buildings consume approximately 39% of the Total Energy produced annually 74% of the Electricity it produced d annually

3 Where does LEED come in?

4 For today we ll focus on: LEED NC-2009

5 Regional Priority LEED NC Possible Points 8 Prerequisites & 1 Prerequisite 110 Possible Points 26 Possible Points 2P Prerequisites it 15 Possible Points 1 Prerequisite 14 Possible Points Innovation In Design 6 Possible Points 1 Prerequisite 10 Possible Points 3 Prerequisites 35 Possible Points

6 Energy and Atmosphere LEED NC 2009 EA 3 Prerequisites 35 Possible Points

7 Energy and Atmosphere What does the LEED EA Category Cover? Energy Performance Commissioning On-Site Renewable Energy Refrigerant Choice Measurement and Verification Green Power

8 Energy and Atmosphere Today we ll focus on three aspects of LEED EA: Energy Performance Commissioning 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 much more cost effective; and you reduce the amount of refrigerant needed, thus reducing its potential impact.

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

10 EA Best Practice Concepts Integrated Design, Construction, Commissioning and Operation: Understanding the relationships between all these different elements is key. Things to 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.; 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.

11 EA Best Practice Concepts Integrated Design, Construction, Commissioning and Operation: Design, construction, and operation must be consistent. Review submittals to ensure conformance to all performance specifications related to EA. Specify and observe construction site practices. Commissioning with enhanced owner/operator training is essential. Need for meticulous follow-through in the whole process.

12 EA in LEED NC 2009 LEED EA Prerequisite 1: Fundamental Commissioning of Building Energy Systems INTENT 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 Incorporate commissioning requirements into CDs Implement a commissioning plan Verify installation and performance of systems in Cx Plan Complete summary report

13 EA in LEED NC 2009 LEED EA Prerequisite 1: Fundamental Commissioning of Building Energy Systems REQUIREMENTS (cont.) 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 systems Renewable energy systems

14 EA in LEED NC 2009 LEED EA Prerequisite 1: Fundamental Commissioning of Building Energy Systems REQUIREMENTS (cont.) Additional potential systems for Cx (not mandatory): Building envelope. Storm water management systems. Water treatment systems Information technology systems

15 EA in LEED NC 2009 LEED EA Prerequisite 1: Fundamental Commissioning of Building Energy Systems IMPLEMENTATION Tasks and responsibilities: Designate commissioning authority - EARLY. Document owner s project requirements (OPR). Review OPR and basis of design Develop and implement commissioning plan (Cx Plan) Incorporate requirements in CDs Commissioning design review (Only for Cx EA Cr. 3) Contractor submittal review (Only for Cx EA Cr. 3) Verify installation and performance of commissioned systems

16 EA in LEED NC 2009 LEED EA Prerequisite 1: Fundamental Commissioning of Building Energy Systems IMPLEMENTATION (cont.) 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 report. Review building operation within 10 months after substantial completion (Only for Cx EA Cr. 3)

17 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance INTENT 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 building energy performance rating for new buildings (5% for major renovations to existing buildings), compared with the baseline building energy performance rating.

18 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance REQUIREMENTS (cont.) Option 1: Calculate the baseline building energy performance rating according to the method in Appendix G, ASHRAE Standard using a computer simulation model for the whole building project. Option 2: Certain projects with relatively low square footage can follow the Prescriptive Compliance Path, using the ASHRAE Advanced Energy Design Guides. These include: Office and Retail Buildings < 20,000 sf; Warehouse or Self Storage Buildings <50, sf; Schools <200,000 sf.

19 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance REQUIREMENTS (cont.) 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 using EPA s ENERGY STAR Target Finder rating tool.

20 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance IMPLEMENTATION ASHRAE Appendix G Energy Modeling: Determine Project Climate Zone

21 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance IMPLEMENTATION (cont.) ASHRAE Appendix G Energy Modeling: Baseline elements prescribed by App. G: Building envelope construction type and min. performance HVAC baseline systems

22 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance IMPLEMENTATION (cont.) ASHRAE Appendix G Energy Modeling: Baseline and proposed models both the same for: Building Configuration (number of stories, floor plans) Space Use Classification Schedules

23 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance IMPLEMENTATION (cont.) ASHRAE Appendix G Energy Modeling: Baseline and proposed models thermal performance adjusted for: Roofs Walls (above and below grade) Exposed Floors Slab-on-Grade Floors Opaque Doors Vertical Glazing (windows, curtainwalls, doors, etc.) Skylights

24 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance IMPLEMENTATION (cont.) ASHRAE Appendix G Energy Modeling: Baseline and proposed models both the same for: Thermal blocks (zoning) Receptacle and Other Loads (25% of baseline cost per LEED)

25 EA in LEED NC 2009 LEED EA Prerequisite 2: Minimum Energy Performance IMPLEMENTATION (cont.) ASHRAE Appendix G Energy Modeling: Baseline and proposed models energy performance adjusted for: Lighting HVAC Systems Service Hot-Water Systems

26 EA in LEED NC 2009 LEED EA Credit 1: Optimize Energy Performance INTENT 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 energy performance rating beyond the prerequisite minimums compared with the baseline building energy performance rating.

27 EA in LEED NC 2009 LEED EA Credit 1: Optimize Energy Performance (1-19 Possible Points) REQUIREMENTS (cont.) Option 1: Whole Building Energy Simulation following ASHRAE 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) 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)

28 EA in LEED NC 2009 LEED EA Credit 1: Optimize Energy Performance REQUIREMENTS (cont.) Option 1: 1-19 Points awarded based on % improvement over baseline:

29 EA in LEED NC 2009 LEED EA Credit 1: Optimize Energy Performance IMPLEMENTATION Energy Standard Requirements Addressed by ASHRAE : 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 permanently wired electrical motors). All options: LEED gives credit for designed (modeled or prescriptive) energy performance.

30 EA in LEED NC 2009 LEED EA Credit 3: Enhanced Commissioning (2 Possible Points) INTENT 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 phase. CxA must be completely independent of design and construction work. Commissioning design document review prior to the mid-construction documents phase.

31 EA in LEED NC 2009 LEED EA Credit 3: Enhanced Commissioning REQUIREMENTS (in addition to PR 1) (cont.) 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

32 EA in LEED NC 2009 LEED EA Credit 5: Measurement and Verification (2-3 Possible Points) INTENT 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) as specified in the International Performance Measurement & Verification Protocol (IPMVP) Vol. III.

33 EA in LEED NC 2009 LEED EA Credit 5: Measurement and Verification (2-3 Possible Points) REQUIREMENTS (cont.) 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 for corrective action if the results of M&V indicate that energy savings are not being achieved.

34 LEED Certification Does it Result in Energy Efficient Buildings? Importance of Performance While good design is important, performance is essential. 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 released March 08. Requested data from LEED certified buildings and analyzed actual usage against model and average building stock.

35 LEED-NC vs CBECS* EUI Some 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,

36 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.

37 Measured vs Proposed Savings Percentages and EUIs Proposed savings averaged 25%, measured savings averaged 28%. Many buildings met anticipated consumption levels, some exceeded expectations, while others failed to meet them.

38 Measured Savings and Credits EA Cr. 3 EA Cr. 5 IEQ Cr.8.1 IEQ Cr.8.2 Enhanced Cx M&V Daylighting yg g Views Achievement of credits does not ensure increased savings.

39 Possible Reasons Modeling vs. Performance Models are built on assumptions Usage levels/schedules may change Behavioral impacts (thermostats, lights, etc) Systems modeled as perfect/functional Implementation Aggressive commissioning i i needed d Weatherization (air barrier) important difficult to predict and model accurately More complicated buildings Advanced controls Complex schedules

40 Building Energy Efficiency and LEED EA Credits Summary / Conclusions On the whole, measured performance of LEED buildings better than the CBECS averages and anticipated i t levels. l But a significant portion of LEED buildings are not performing up to expectations. Corrective actions needed Better, more realistic modeled assumptions More aggressive commissioning and M&V Sustained operation must emphasize energy Knowledgeable and assertive users

41 LEED Influence New LEED projects must submit 5 years of performance 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:

42 EA Case Studies University of Illinois Business Instructional Facility Owner s Re-Commissioning. Normal Children s Discover Museum SEDAC Energy Audit. SEDAC Re- (? Retro-) Commissioning.

43 Energy and Atmosphere What does SEDAC do? Promote Efficient Use of Energy Resources Provide Free Advice and Analyses Make Recommendations for Intelligent Building Design and Operations Efficient Building Components and Systems

44 Thank you! Thank you!