6/27/2008. Operated for the U.S. Department of Energy by Midwest Research Institute & Battelle

Transcription

1 Zero Energy Buildings: Smoke? Mirrors? or What? Ron Judkoff Director, Buildings & Thermal Systems Center National Renewable Energy Laboratory Operated for the U.S. Department of Energy by Midwest Research Institute & Battelle National Renewable Energy Laboratory (NREL) 1000 Scientists dedicated to develop green energy technologies Photovoltaics Wind, Hydrogen Biofuels and Transportation Buildings & Thermal Systems Center Buildings: Solar, efficiency, ZEB Concentrating Solar Power (Solar Thermal Electric) Geothermal Heat Pumps 1

2 64 MWe Trough Plant CSP SEGs Troughs Thermal Systems Polymer Solar Water Heaters NREL Buildings Group Measurement and simulation of building energy, comfort, lighting, and air quality Ultra efficient Design: Commercial, Residential, and Manufactured buildings Passive/Active Solar, & PV for Buildings Advanced HVAC systems and BCHP Design/Analysis/Optimization Computer Tools ZEBs 2

3 US Building Energy Use (2004) Primary 39% (39 quads) Other 9% SEDS 8% Heat 24% Electric 71% (27 quads) Ice shelves on the melt. MELS 13% Refrig. 7% Light 18% DHW 10% Cool 11% Buildings CO2 Primary 620 MTC/y Electric 450 MTC/y The Smoke Buildings USA Global CO 2 38% 9% SO 2 52% NOx 20% CO 3% VOCs 6% US=5% World Population, 24% Global Carbon. 1 House = 1.5 Cars CO2 3

4 Buzzword Madness First Published Green LEED Platinum Sustainable Zero Energy Carbon Neutral Hi Performance Low Energy Conservation Energy Efficient Solar Bioclimatic Le Bioclime PassiveHaus Example Building LCA, Athena EIE 4

5 Example Building LCA, Athena EIE It s the Energy. 96% 4% Buildings in a Test-tubetube Federal Low Income Weatherization Program 5

6 Whole Building Optimization and Systems Integration Research Goal: ZEH by 2020, ZECB by 2025 Energy Design Process Simulate Construct Test/Monitor When Materials Selection was Easy! New Problem: Too much technology to choose from 6

7 Evolutionary Elimination of Bad Architects & Engineers BIPV Product Examples Flexible roof-top PV shingles PowerGuard system Light, flexible PV roofing shingle for direct rooftop mounting PV roofing shingles Building-integrated PV metal roofing modules 7

8 Zero Energy Definitions A zero energy building (ZEB) is ultra efficient such that the energy needs are met with renewable technologies on an annual basis. Zero site energy Zero source energy Zero energy costs Zero emissions On-site ZEB Off-site ZEB NREL Zero Net Site Energy Habitat House -Walls: R40 - Roof: R60 - Passive - SDHW - PV: 4 kw -Heat Recovery 8

9 NREL/Habitat ZEH Daily and Cumulative Net Electricity Production Production Daily net kwh production Consumption Daily Net Electricity Production Cumulative net kwh consumption -40 Feb 06 Mar 07 Apr 06 May 06 Jun 06 Jul 06 Aug 06 Sep 06 Oct 06 Nov 06 Dec 06 Jan 07 Feb 07 Mar 07 Apr 07 Month May 07 Jun 07 Jul 07 Aug 07 Sep 07 Oct 07 Nov 07 Dec 07 Jan 08 Feb 08 Mar Cumulative Net Electricity Production Example Results: Costs and Energy Savings of All Possible Combinations of Options (BEopt-R) 9

10 Example: Greensburg Neutral Cost Package 1 R22 wall assembly (2x6: R-19 batts+ foam sheathing) R50 ceiling assembly R10 basement.0001 SLA (2 ACH 50 ) Low e/low SHGC glazing, Argon Fill (0.28 U-value, 0.37 SHGC) 80% CFL Lighting SEER 18 AC AFUE 90+ furnace Gas tankless hot water, EF 0.8+ Tight ducts (Mastic, 5% Leakage), in conditioned space Energy Star Appliances 1.5 kw DC PV System BA QA (moisture control, ) Estimated cost increase relative to standard home 2,3 : +$10.00-$13.00/ft2 Notes: 1. Equivalent packages may be substituted, based on specific builder preferences 2. Does not include costs associated with builder/contractor training and changes in business practices. 3. Incremental costs will depend on current builder practice Estimated Annual Costs: Neutral Cost Target Greensburg Estimated Incremental First Cost Relative to Standard Practice $26,000 Annual Amortized Cost $1386 7%, 30Year mortgage 1 Annual Utility Bill Savings $1386 Net Annual Savings $0 (2000 ft2, 2-story, 16% window to floor area ratio), unconditioned basement 1 Assumes 28% marginal tax bracket and includes present value of future replacements of equipment over 30 year life of mortgage. 10

11 Commercial Buildings End Use Splits: Primary Energy Cook 2% Other/SED 23% Light 25% Vent 6% DHW 6% Refrig 6% Plug 8% Cool 11% Heat 13% No Silver Bullets Percent of floor area able to reach ZEB goal All Office/professional Warehouse (nonrefrigerated) Education Retail (excluding mall) Public assembly Service Religious worship Lodging Food Service Health Care Inpatient Public order and safety 14 3 Food sales Health care (outpatient) Vacant Other Skilled nursing 0 0 Laboratory Refrigerated Warehouse 8 Subsector Figure 4-11 Percentage of floor area that can reach ZEB goal: Max Tech scenario 11

12 BigHorn Cambria Oberlin Chesapeake Zion TTF 100% 90% 80% 70% 16 Results Percent Net Source Energy Savings Percent Net Site Energy Savings Percent Site Energy Savings Percent Energy Cost Savings 25 kbtu/ft2/yr LEED Platinum? Percent Savings 60% 50% 40% % 40 20% 10% 0% Oberlin BigHorn TTF Cambria Zion CBF 12

13 On the Path to Commercial ZEBs Oberlin Lewis Center for Environmental Studies -14,000 ft2 Classroom and Offices - 60 kw PV - Daylighting - Natural Ventilation - Ground Source Heat Pump Daily Average Monthly Consumption and Produc (kwh/day) 1,600 1,400 1,200 1, Oberlin Before & After Fixes Control fix to EB-1 Utility Bills Equipment Total Lights Total Cooling Total Heating PV Production HP swap-out 0 Jan-00 Feb-00 Mar-00 Apr-00 May-00 Jun-00 Jul-00 Aug-00 Sep-00 Oct-00 Nov-00 Dec-00 Jan-01 Feb-01 Mar-01 Apr-01 May-01 Jun-01 Jul-01 Aug-01 Sep-01 Oct-01 Nov-01 Dec-01 Jan-02 Feb-02 Mar-02 Apr-02 May-02 Jun-02 Jul-02 Aug-02 Sep-02 Oct-02 Nov-02 Dec-02 Jan-03 Feb-03 13

14 Oberlin PV Carport Y/Year x Y Low-E Glazing - Economic Analysis $/Year Y Y Y Y Y 83Y Heating Cooling HVAC Aux. Lighting % Glass on A ll Facades 14

15 Signature Center Denver West NREL STF: 1 st LEED Platinum Federal Bldg Operated for the U.S. Department of Energy by Midwest Research Institute & Battelle 15

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17 Zion Visitor Center 7.2 kw PV system (UPS) Passive evap cooling & natural ventilation (automatic windows) Excellent thermal envelope Trombe walls, direct gain, thermal mass Shading Daylighting Radiant heating 17

18 Where we are today Where we are if all buildings were built to code Assessment potential 18

19 Lessons: Get an A&E that uses Energy Design Process In house energy modeling or consultant Energy simulation used early and often throughout design process Charettes: whole design team in sync Commissioning: pre and post occupancy Innovative system controls and interactions will take awhile to perfect Beware of A&Es who use daylighting as a license to glaze! Use aesthetic budget to pay for architectonic energy features Advanced Energy Design Guides Partnership with AIA, USGBC, ASHRAE, IESNA DOE has funded the analysis and some production costs Member organizations train and sell materials 30% Small Retail, Small Office, K-12 Schools, Warehouses 19

20 AEDG s continued 30% series looks at what is easily achievable today Long term plan Other Building Types 50% series 70% (or net-zero series) High Performance Buildings Database What do we mean by Zero Energy Buildings? Probably not this! People in houses like these strive for a higher quality of life. This will take lot s of energy. My Zero Energy House in Burkina Faso,

21 Pacala-Socolow Stabilization World Wedge Model Business as Usual Must keep Global CO 2 emissions < 6600 MTC/yr to keep concentration below 500 ppm (tipping point) MTC/yr U.S Part of Problem World = 6500 US emits 1550 US Bldgs: 620 To keep world emissions constant as developing nations grow, US must reduce emissions 80% by 2050 (reduction of 1200 MTC/yr by 2030) 21

22 Year Quads year mmtce Quads Year Residential and Commercial New Construction Residential and Commercial Retrofit Source (Cum) Source Quads Source Energy Quads Saved Quads Costs Source Saved (Cum) to Energy Source Costs Saved Site Quads Saved Costs Quads (Cum) to end of life of Costs Saved Year Quads ($ Billions) (Cum) Saved (Cum) (billion $) Year ($ Billions) Saved/yr 2030 retrofit ($ Billions) Assumptions: Assumptions: PV Efficiency = 10% We can save 20% of Source energy in existing buildings at a 1 year payback PV Capacity Factor = 20% We will retrofit all existing buildings in the next 10 years PV cost = $3000/kWp = 100 ft2 of roof area We will cover all PV appropriate roof area on existing buildings with PV in the next 10 years PV cost = $3/Wp = $30/ft2 of roof area From EIA Data, 2005 building energy cost for 40 quads source energy was $317 billion PV cost = $200 billion/source quad 187 quads is from efficiency and 197 quads is from PV Grid can accept all generated PV EIA data 2003: 38.8 quads = MMTCE = 16 MMTCE/Quad Net metering is in effect There are about 60 billion ft2 of pv appropriate roof area There will be 20B ft2 of new PV appropriate roof area by 2030 The cost to cover 60 billion ft2 would be about $1.8 trillion This is from new construction to 2030 Discount rate above inflation = fuel escalation rate above inflation 1 Quad of building source energy = $8 billion 1 Quad of building site energy = 2 Quad of Source energy on average 100 Quads = 30 million GWh/yr Electric Site to source conversion = 3.2 Gas site to source conversion = 1.08 MTC/yr years Series1 6/27/2008 A Modest Proposal If I were King Starting 2008 all new US buildings shall meet or exceed neutral cost point All PV Usable Roof area in new buildings get PV For next 23 years, each year 1/23 of all existing buildings retrofit to save 10% site energy = 20% source energy (assume 1 to 3 yr payback) 1/23 of all existing usable roof area gets PV Quads/yr Primary Building Energy MTC/yr PV efficiency = 10% PV Cost = $3 Wp PV Capacity factor = Bft2 of new PV usable roof area by Bft2 of PV usable existing roof area as of 2008 Electric site to source factor = % efficiency savings at no cost for new buildings All raw data taken from EIA Discount rate above inflation = fuel escalation rate Avg life of PV & EE retrofits =25yrs 22

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25 The gift that keeps on giving! $113 B/yr $25.5 B/yr Perspective on Costs: Whole enchilada = $113 B/yr to 2030 and we get our money back with profit! Stimulus Package = $150 B Building Energy Cost = $350 B/yr Bldg Industry: $1.1 T/yr = 10% GDP EE only = $11 B/yr 25

26 It s not smoke. It involves some mirrors. We can do it if we have the national will! End 26