Presentation is loading. Please wait.

Presentation is loading. Please wait.

1 Proposed Revision to Energy Star New Homes Deemed Savings September 19, 2008.

Similar presentations


Presentation on theme: "1 Proposed Revision to Energy Star New Homes Deemed Savings September 19, 2008."— Presentation transcript:

1 1 Proposed Revision to Energy Star New Homes Deemed Savings September 19, 2008

2 2 Background – Why Update Savings Current Savings Estimate Do Not Reflect Current Standards and Market Conditions –Heat Pump & CAC Current Baseline = HSPF 7.0/SEER 11 Revised Baseline = HSPF 7.7/SEER 13 (New federal standard) Energy Star minimum = HSPF 8 (original) vs. HSPF 8.5 (new) –Dishwasher Current Baseline = EF-52 Revised Baseline = EF-60 (AHAM 2004 sales weighted average EF) Energy Star minimum = EF-58 (original) vs. EF-65 (new Energy Star spec) –Windows Current Baseline = Class 40 Revised Baseline = Class 35 (Based

3 3 Background – Why Update Savings Energy Star Lighting –Current estimates do not reflect “new construction” lighting power densities –Alternative Energy Star lighting “packages” not integrated into savings estimates Thermal shell baseline not consistent with revised energy codes Heat Pump “Control Mix” Do Not Reflect Results of Regional Heat Pump Evaluation –Current assumptions too pessimistic for “baseline” –PTCS assumptions slightly pessimistic, but probably OK

4 4 Heat Pump Control Strategies IdealIdeal - ARI controller from testing method Comfort AssistComfort Assist - First stage ER operates below 30º Five PlusFive Plus - 5 kW first stage with the compressor, all temperatures Low AmbientLow Ambient - Compressor off below 30º, ER only Outdoor TstatOutdoor Tstat - Ideal controller with ER lockout above 40º

5 5 Current Assumed Control Weightings – Base Case

6 6 Control Weightings RTF– 2003 calculation, used current EStar calculator and “deemed savings” values ETO—2005 weighting for Energy Trust of Oregon Resource assessment Estar Homes—2005 weighting used in EStar savings estimates for Alliance HP2005—Results of Heat Pump study

7 Alternative Control Weightings Impact on Heat Pump System Efficiency & Performance Ideal RTF-Base ETOEstar Homes HP2005 ARI Controller100% 0% 50%10% 40% Comfort Assist 60% 0% 15% Plus 5 20% 40%30% 25% Low-ambient cutout 20% 10%60% 15% Outdoor Tstat 0% 5% Performance Zone 14,451 5,176 5,4355,440 5,117 86% 82% 87% Zones 2 & 39,206 11,803 10,77312,322 10,587 78% 85%75% 87%

8 8 Control System Assumption Impact on System Efficiency – Current Assumptions

9 9 Recommended Calculator Revisions Since Heat Pump now require Outdoor Tstat and set-up for ODT PTCS control assumptions should be revised to include “Ideal” controller and “Outdoor T” controller Base Case control assumptions should be adjusted to more closely reflect field observations

10 10 Recommended Revised Control Weightings

11 11 Revised Control System Assumption Impact on System Efficiency

12 12 New Home Lighting Power Densities Are Higher Than Currently Assumed Current LPD Assumption Source: NEEA New Construction Survey

13 13 New Homes Have Double the Currently Assumed Number of “Sockets” Source:NEEA New Construction Survey Current Assumption

14 CALMAC Results = No Correlation Between House Size & Average Hrs of Lighting Use Source: CFL Metering Study – Final Report. Prepared for Pacific Gas & Electric Company, San Diego Gas & Electric Company and Southern California Edison by KEMA, Inc. February 25, 2005

15 15 Proposed Revised Energy Star Lighting Savings Assumptions Current Assumptions – 15 CFLs installed per home operating 2.67 hrs/day Proposed Revised Assumptions (and specifications) –Energy Star Lighting Package 1 (minimum) = 30 CFLs –Energy Star Lighting Package 2 = 45 CFLs* –Energy Star Lighting Package 3 = 54 CFLs** –All packages assumed to operate 2.0 hrs/day *or maximum hardwired LPD of 0.8 Watts/sq ft ** or maximum hardwired LPD of 0.6 Watts/sq ft

16 16 Proposed Revised Energy Star Deemed Savings for Lighting Packages

17 Current Baseline Thermal Shell Assumptions ComponentZone 1Zone 2Zone 3 Attic0.030 Door0.187 Floor0.029 Infiltration0.35 Joisted Vault0.034 Slab-on-Grade (F-Value/lin.ft. perimeter)0.52 Trussed Vault0.039 Wall0.058 Wall Below Grade (Interior)0.037 Slab-below-Grade (F-Value/lin.ft. perimeter)0.57 Window0.388

18 Proposed Revised Baseline Thermal Shell Assumptions – Alternative 1 (code) ComponentZone 1Zone 2Zone 3 Attic Door0.187 Floor Infiltration0.35 Joisted Vault0.034 Slab-on-Grade (F-Value/lin.ft. perimeter)0.52 Trussed Vault0.039 Wall Wall Below Grade (Interior)0.037 Slab-below-Grade (F-Value/lin.ft. perimeter)0.57 Window0.34

19 Proposed Revised Baseline Thermal Shell Assumptions – Alternative 2 (Current Practice) ComponentZone 1Zone 2Zone 3 Attic Door0.187 Floor Infiltration0.35 Joisted Vault0.034 Slab-on-Grade (F-Value/lin.ft. perimeter)0.52 Trussed Vault0.039 Wall Wall Below Grade (Interior)0.037 Slab-below-Grade (F-Value/lin.ft. perimeter)0.57 Window

20 20 Estimated Energy Star Home Deemed Savings Using Alternative Thermal Shell Assumptions

21 21 Proposed Thermal Shell Revisions Alternative 1 –Uses code as baseline, avoids paying incentives to “meet” code –Does not reflect actual building practice Alternative 2 –Reflects actual incremental improvement in thermal shell, hence savings –Does not appear to reflect current market share of Energy Star windows

22 22 Current and Revised Energy Star Homes Deemed Savings - Zonal

23 23 Current and Revised Energy Star Homes Deemed Savings – Gas Furnace w/o CAC

24 24 Current and Revised Energy Star Homes Deemed Savings – Gas Furnace w/ CAC

25 25 Energy Star Homes Revised Deemed Savings Relative to Existing Deemed Savings - Crawlspace

26 26 Energy Star Homes Revised Deemed Savings Relative to Existing Deemed Savings – Half Basement

27 27 Energy Star Homes Revised Deemed Savings Relative to Existing Deemed Savings – Full Basement

28 28 Current and Revised Energy Star Homes Deemed Savings – Heat Pump* *Reflects revised control assumptions, does not include lighting, DHW or dishwasher


Download ppt "1 Proposed Revision to Energy Star New Homes Deemed Savings September 19, 2008."

Similar presentations


Ads by Google