Ductless Heat Pumps (DHP) in Single Family Homes with Zonal Electric Heat UES Measure Update

1. Ductless Heat Pumps (DHP)in Single Family Homes with Zonal Electric HeatUES Measure Update Regional Technical Forum June 17, 2014

2. Measure Overview Staff Highlighted Areas Summary of Updates Measure Materials Summary of Changes to Savings, Cost, TRC Proposed Decision Today’s Agenda

3. Current Category: Proven • Current Status: Active • Current Sunset Date: 1/31/2017 • Reason for Update/Review: Integration of U0-based SEEM calibrationadopted at the May 2014 RTF meeting expected to change savings by more than 10 percent • New calibration DHP Measure Overview

4. None (except for David Baylon’s issue - we’ll get to that…) Staff Highlighted Areas

5. Minor update to U0-based DHP calibration presented in May • Discovered some supplemental fuel heating in the DHP 95-population used for Phase I Calibration • Phase I Calibration should contain no non-electric supplemental fuel heating • Staff filtered out supplemental fuel users from Phase I dataset (nine homes) • Caused minor change in calibration parameter “theta” (0.55 to 0.53), causing slight decrease in DHP electric heating consumption Summary of Updates

6. Integrated U0 calibration with new savings calculation method (i.e. S2 rather than S1) into DHP measure analysis • Major workbook renovation • Cleaned up and reorganized UES measure workbook (removed old calibration work) • Developed SEEM analysis workbook using new SEEM template • This is linked to the UES measure workbook • Developed stand-alone Calibration workbook • Also linked to UES measure workbook Summary of Updates (continued)

7. Measure Materials Calibration SEEM Analysis UES Calibration Workbook DHP UES Workbook • DHP SEEM Analysis Runs DHP Calibration Report • Documentation and derivation of Phase I/II calibration • SEEM inputs and outputs • Derivation of unscreened heating savings • Derivation of screened heating savings and cooling savings (all) • Summary of total savings, cost, TRC

8. Major changes • Basing calibration of savings on pre/post consumption (i.e., on S2 rather than pre/post savings, S1) • Affects HZ3 more significantly than HZs 1 and 2 • Adjustment for partial occupancy and misbehaved bills • Causes a 10-15% reduction in savings across all zones • Heating Savings: • Unscreened • HZ1 savings down from 2,719 to 2,395 kWh/yr • HZ2 savings downfrom 2,604 to 2,381 kWh/yr • HZ3 savings up from 311 to 873 kWh/yr • Screened (applicable to HZ3 only) • PASS screen savings up from 1,339 to 1,558 kWh/yr • FAIL screen savings up from 157 to 702 kWh/yr Summary of Changes to Savings, Cost, TRC

9. Cooling Savings • No change • Cost • No change • TRC • Cost-effectiveness unchanged for most measures • See “Presentation” tab of UES workbook for changes Summary of Changes to Savings, Cost, TRC (continued)

10. David Baylon would like us to revisit the Phase II calibration for single family houses • Issue is how we handled “unoccupied houses / misbehaved bills.” Currently VBDD estimates are used within the regression. • Options: • Throw them all out • Zero them all out • Leave as-is (use VBDD estimates) Staff Highlighted Areas

11. Throw them all out • Assumes “unoccupied/misbehaved” houses consume as much heating energy as the average. • Zero them all out • Assumes “unoccupied/misbehaved” houses use no heating energy. • Leave as-is • Uses completely unreliable VBDD estimates for heating energy, but it is less extreme than the alternatives. Highlighted Areas (continued)

12. “I _____ move to: A: “Approve as proposed the updates to the Ductless Heat Pumps (DHP) in Single Family Homes with Zonal Electric Heat UES measure and [direct]/[don’t direct] staff to revisit Phase II for the misbehaved/unoccupied house adjustment.” Or B: “Revisit Phase II for misbehaved/unoccupied house adjustment before finalizing the DHP UES.” Proposed Decision

13. Backup Slides

14. DHP Re-Calibration Moving to Uo-based Calibration (away from Thermostat-based Calibration) Regional Technical Forum May 13, 2014

15. Phase IAdjustment to SEEM Output to Match Bills(for Houses with “well-known” Heating Energy Use)

16. Existing DHP Phase I Calibration, approved in July 2013, is based on the old Thermostat Setting calibration method: Background: DHP Calibration

17. Goal: Determine Uo-based Phase I Calibration Factors for DHPs

18. Use DHP Metering Study data (n=95 pre billing, post metering) to interpolate between the Zonal/eFAF and HP/gFAF calibration factors. • See the following for more details: • “DHPphaseIcalibrationMemo” document • “DHP_SEEM_calibration_PhaseI” workbook • Two equally legitimate methods of interpolating, both give slightly different answers • Average of Interpolations (=0.60) • Interpolation of Averages (=0.55) Methodology

19. Comparison “Interpolation of Averages”, or =0.55, was selected since it results in overall savings closer to the original for the DHP UES measures.

20. Proposed Calibration Factors(DHP in Green)

21. “I _____ move that the RTF adopt the revised Uo-based Phase I calibration adjustment factors for DHP’s.” Decision

22. Phase IIAdjustment to Electric Energy Use for Non-electric Fuel usage, Unoccupied Houses, and houses with otherwise misbehaved bills

23. Phase II Adjustments: • For program-like houses (permanent electric heat, no non-electric FAF or boiler), the adjustments address: • Non-utility heating sources, • Program-permitted gas heat sources (e.g., gas fireplaces), and • Other SEEM Phase I calibration filters • See September 2013 RTF meeting presentation for more details Background Today’s Goal: Determine values for DHP.

24. Source: DHP Pilot Study, R2≥0.45 Available Data Source: RBSA SF, Zonal Electric Source: SEEM runs, Phase I applied

25. The next two slides show the two methods in detail. • The difference between the two methods (in words): • S1 uses the ratio of savings from the average house to non-supplemental fuel houses. • S2 uses the ratio of energy use from the average house to non-supplemental fuel houses. • Q: Which one’s better, correct? • Theyseem to offer the same correctness. • S2 aligns better with our guidelines: Determines baseline and efficient case consumptions separately. • The S2 Method will allow us to generate Phase II calibration factors for DHP’s (The S1 Method will not). • The S2 Method aligns with our need to assign a separate “wood heat” adjustment factor to DHP’s. • But they give different answers (especially in HZ3): Two UES Analysis Methods • Whether we should revisit the DHP UES is out of scope for this presentation.

26. Background: DHP UES Savings Methodology

27. Background: DHP UES Alternative Methodology

28. Proposed Methodology We continue to have no fully satisfying solution. Supplemental fuels use has been a difficult thing to pin down; it still requires a fair amount of judgment for DHP’s.

29. Remember there’s a component of the adjustments that represents unoccupied houses and houses with otherwise misbehaved bills. We’ll assume DHP houses, on average, have the same results as other heating systems (which are based on RBSA data). Step 1 – Apply implied adjustment to DHP

30. The DHP Pilot data and UES savings methodology does not make adjustments for unoccupied houses or houses with misbehaved bills We’ll re-calculate the “eFAF, Zonal, HP, or Gas FAF” electric heating adjustments without the implied adjustment: This is R2.Z from the alternative method above (S2 method), but using RBSA specific data, rather than DHP Pilot data. Step 2 – Re-state Known Adjustments

31. Step 3 – Find R2.D(RBSA) by using S2 from the DHP UES alternate analysis. Solve for R2.D(RBSA)

32. Step 4 – Work backward to fill in the blanks. Negative value doesn’t make sense, we’ll need to fix that.

33. Step 5 – Re-assign negative value in HZ3. Again, not a completely satisfying solution, but it doesn’t affect savings too much: S2 for HZ3 changes from 970 kWh/yr to 1,043 kWh/yr with this “tweak”.

34. “I _____ move that the RTF adopt the Phase II calibration adjustment factors for DHP’s.” Decision