Compliance with. Senior Research Engineer Pacific Northwest National Laboratory. CRC 2008 ASHRAE RAL Lisbon, Portugal October 15, 2008

Transcription

1 Compliance with ASHRAE 90.1 and LEED Bing Liu, P.E., C.EM., LEED AP Senior Research Engineer Pacific Northwest National Laboratory CRC 2008 ASHRAE RAL Lisbon, Portugal October 15, 2008

2 The Challenge Buildings account for 1/3 of the world s energy and materials consumption 40% of GHG emissions result from energy consumption in buildings Huge growth in global energy consumption expected as standards of living increase 2

3 ASHRAE s Response Greater Efficiency i Today: Blue Skies Tomorrow. ASHRAE Past President Kent Peterson: ASHRAE focuses on the Sustainability through Advanced Energy Design. The ASHRAE Promise: A Sustainable Future. ASHRAE Past President Terry Townsend: ASHRAE members must carry the fire to help provide for a sustainable future. Sustainability: Meets the needs of the present without compromising the ability of future generations to be able to meet their needs. 3

4 Topic of Discussions Incentives on Green Building Designs LEED Rating System ASHRAE (Appendix G) 4

5 Incentives on Green Building Designs Tax Incentives EPACT 2005 provides tax incentives for buildings whose energy performance meets or exceeds 50% above ASHRAE Some states and cities offer tax incentives for buildings that meet green building codes or become LEED certified. Federal Leadership EO 13423: High performance buildings to include sustainability principles p such as LEED. EO 13423: Energy Performance for New Construction to be 30% better than ASHRAE Standard GSA new building projects must meet LEED certification requirements. Higher Market Values Green becomes es the main stream and higher market values. Wal-Mart s commitment on sustainability and beyond 5

6 LEED Rating System A recognized standard d for the construction ti industry to assess the environmental sustainability of building designs. A framework for integrated design A point based rating system 6 topic areas 34 credits and maximum of 69 points 4 performance ratings 52+ points 39 points 33 points 26 points 6

7 Economics of LEED LEED Rating Certified Silver Gold Platinum LEED Points 26 to to to to 69 Energy Savings 25 to 35% 35 to 50% 50 to 60% >60% Annual Utility $0.75/ft 2 $1.00/ft 2 $1.25/ft 2 $1.50/ft 2 Savings Typical Payback Under 3 yrs 3-5 yrs 5-10 yrs 10+ years Incremental Construction Cost Small Buildings 3% 7% 10% 15% Large Buildings 1% 3% 5% 8% 7 Source: Enermodal Engineering

8 LEED for New Construction Buildings 8

9 LEED-NC Point Distribution 6 LEED Topic Areas Indoor Environmental Quality 22% Innovation & Design Process 7% Sustainable Sites 20% 9 Materials & Resources 19% Energy & Atmosphere 25% Water Efficiency 7%

10 LEED Energy Credits Prerequisites Fundamental Building Systems Commissioning Minimum Energy Performance Meet ASHRAE or local energy code - whichever is more stringent CFC Reduction in HVAC&R Equipment 10

11 LEED-NC 2.2 Optimize Energy Performance 2 points mandatory for all LEED for New Construction ti projects registered after June 26, 2007 Option 1: Whole Building Energy Simulation (1-10 Points) Baseline: ASHRAE Appendix G Option 2: Prescriptive Compliance Path: (4 Points) Advanced Energy Design Guide for Small Office Building (by ASHRAE and its partners, up to 20,000 sf) Option 3: Prescriptive Compliance Path: (2-5 Points) Advanced Buildings Core Performance Guide (by New Building Institute, up to 100,000 sf ) 11

12 Advanced Energy Design Guides The AEDG series are intended d to provide a simple and easy approach for use by small buildings contractors and designers. The initial series es of guides have an energy e saving target of 30% better than ASHRAE Standard , but the energy analyses show the savings of 30% better than Standard Free download at 12

13 Advanced Energy Design Guides AEDG Energy Savings 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% 42% 40% 38% 37% 35% 33% 31% 30% Small Office Small Retail K-12 School Warehouse Savings over Savings over Source: Pacific Northwest National Laboratory

14 Whole Building Energy Simulation Credits Based on Performance above ASHRAE Appendix G New Buildings Existing Buildings Points 10.5% 3.5% % 7.0% % 10.5% % 14.0% % 17.5% % 21.0% % 24.5% % 28.0% % 31.5% % 35.0% 10

15 ASHRAE Standard 90.1 Provide minimum requirements for the energy- efficient design of buildings except low-rise residential buildings. 15

16 Scope of Standard 90.1 New buildings and their systems New portions of buildings and their systems (additions) New systems and equipment in existing buildings (alterations) Does not apply to: single family, or low-rise (3 story or less) residential buildings building systems that use energy primarily for process or industrial use 16

17 Organization of Standard Purpose 7 Service Water Heating 2 Scope 8 Power 3 Definitions iti 9 Lighting 4 Administration and 10 Other Equipment Enforcement 11 Energy Cost Budget 5 Building Envelope (ECB) Method 6 Heating, Ventilating, and Air-Conditioning 12 Normative References 17

18 Appendix G Performance Rating Method - General NOT PART OF STANDARD; merely informative Intended for use in rating energy efficiency of building designs that exceed the requirements of the Standard. Provides standard procedures for rating the energy efficiency of the entire building Gives credit for advanced design strategies 18

19 Appendix G Differences from ECB Method NOT an alternative compliance path to comply with the Standard Performance rating method includes the total energy consumption for all end uses Credit is offered for better building orientation Interior or exterior automatic shades maybe modeled and credited Credit for occupancy sensors and timers for lighting Greater credit for HVAC system selection 19

20 Appendix G Simulation General Requirements Simulation requirements similar il to ECB Method Exception: Appendix G requires 8,760 hours per year model ECB needs only 1400 hours per year model Comparison between Proposed and Baseline Building Performance in Table G3.1 20

21 Appendix G Schedules Changes to schedules allowed for energy efficiency measures: lighting controls natural ventilation demand control ventilation measures that reduce service water heating loads and more 21

22 Appendix G Building Envelope Baseline building orientation and fenestration locations normalized in model Baseline Envelope meets code requirements for common construction type (lightweight assembly) Only automatically controlled shading devices may be modeled 22

23 Baseline Building Fenestration Layout ECB Method Glazing area is equal to design or 40% of gross above grade wall area (whichever is smaller) Glazing locations are equal to design Appendix G Glazing area is equal to design or 40% of gross above grade wall area (whichever is smaller) Glazing distributed uniformly in horizontal bands across all four orientations 23

24 Baseline Building Orientation ECB Method Actual Building Orientation Appendix G Average of 4 Building Rotations

25 Baseline Building Envelope Type ECB Method Proposed Design Envelope type Appendix G Common Lightweight Assembly types Example: A concrete building in Jacksonville, FL: ECB: U = for mass wall Appendix G: U = for steel-framed wall 25

26 Appendix G Lighting Model daylighting via software or schedules Automatic lighting controls through the power adjustment percentage or schedules 26

27 Appendix G Baseline HVAC System Type Depending on the Number of Floors and Building Size 27

28 Appendix G Baseline HVAC System Requirements Equipment sizing safety factors - 15% %for cooling and 25% for heating Economizers pertablesg3126a G A, B, C Supply fan power sizing criteria defined Energy recovery criteria defined Demand control ventilation - allow to adjust ventilation rates in the proposed design 28

29 Appendix G Baseline HVAC System (contd.) Hot water pumping, HW supply temp & reset criteria defined 19 w/gpm, threshold for variable pumping Chiller plant criteria CHW pumping, CHW supply temp & reset criteria defined 22 w/gpm, threshold for variable pumping Heat rejection and pumping criteria 29

30 Appendix G Baseline HVAC System (contd.) Supply air temp reset criteria i VAV minimum criteria 0.4 cfm/sf Fan power boxes criteria i w/cfm VAV main fans part-load performance defined 30

31 Energy Modeling: Results only as good as inputs DOE-2 equest ( EnergyGauge Summit ( EnergyPlus ( g g gyp DesignBuilder ( 31

32 If You Have a Question or Two Feel Free to Contact: Bing Liu, P.E. at Bing.liu@pnl.gov (509)