Heat Pump Water Heaters in Northern Climates: A summary of Experience & Recommendations for the Future

Transcription

1 Heat Pump Water Heaters in Northern Climates: A summary of Experience & Recommendations for the Future Presentation to ACEEE Hot Water Conference Jeff Harris Northwest Energy Efficiency Alliance June 9, 2009

2 Northwest Energy Efficiency Alliance Non-profit organization funded by electric utilities in four Northwest States: Idaho, Montana, Oregon, & Washington Mission: Mobilize the Northwest to become increasingly energy efficient for a sustainable future Focus on market transformation working in collaboration with Northwest Utilities Annual funding: ~ $25 million/year; overall utility EE program investment in NW ~ $250 million/year

3 It s Hard to Improve on a Good Thing... The Electric Resistance Water Heater: Cost <$500; <$400 for smaller sizes Can be installed by DIY for almost no cost or plumber for ~$200 Only 3 connections: hot/cold water and electricity No moving parts No noise No maintenance No customer interaction required Nearly 90% efficient...

4 Why we should try: A NW Perspective. Still have large saturation of electric water heat in NW ~60% or just under 3 million water heaters If 40% could be converted to HPWH, energy savings potential is ~ 500 amw; the size of one large coal-fired power plant. Nationally, estimated 100 million households with electric water heat. If all national water heaters converted, estimated savings equivalents to over 20,000 amw of power plant or over 40 coal fired power plants.

5 NW Experience with HPWH: Every Decade has its HPWH 3 generations of HPWH Technology: Round 1 Early 1980 s Round 2 Early 1990 s Round 3 Early 2000 s

6 First Gen: Early 1980 s Technology: Add-on units with external pumps/heat exchangers Bonneville Power Administration Program installed hundreds as part of Solar/HPWH program Market: Driven entirely by tax credits and utility incentives; no major manufacturers involved Evaluation results: Very poor reliability Poor performance Poor customer satisfaction

7 Second Gen: Early 1990 s Technology: Integral design, heat exchanger wrapped around tank, exhaust-air operation Targeted at new construction program; one small manufacturer selling through local distribution Evaluation: COP s around 2.0; Design worked: refrigeration components, exhaust-air successful strategies for NW climate. Most problems traced to manufacturing problems that could be corrected with better Q/A; main problems in marketing and distribution; weight an issue.

8 Can HPWH last? You bet... Installed in Still running

9 Third Gen: Early 2000 s Market Optimized HPWH based on DOE/TIAX studies. NW tested several demonstration units; CA ~ 20; NE ~20. Technology: Integral design, large area heat exchanger, costoptimized design for drop-in installation Market: Demonstration only in NW; larger scale demos programs in other locations Evaluation/Assessment: Technology performed well; Key issues with reliability traced to electronic controls failures; primary consumer issues around noise, condensate problems, and cold basements.

10 Key Learnings from Northern Climates The good news: Technology exists to meet HPWH performance targets of COP 2.0 or better Significant benefits identified: Improved ventilation Dehumidification

11 Key Learnings from Northern Climates Rule number 1: Can t be any worse than the current electric water heater of equivalent size/capacity; i.e. must deliver at least same amount of water with no additional hassles for homeowner and no sacrifices in comfort or aesthetics... That means: Reliability, reliability, reliability... No Noise (at least no worse than anything else) No cold air pooling on the floor No condensate dripping on the carpet No monthly maintenance Can t freeze if accidentally placed in freezing conditions

12 Draft Northern Tier Specifications for HPWH New HPWH entering the market in 2009/2010 Northern climates have special needs related to this technology ENERGY STAR specification does not cover all of these needs. Coalition of Northern Tier utilities, market transformation organizations and others to define a specification for appropriate installation in Northern climates. Includes Northwest, Midwest, Northeast; over 20 states represented all together;

13 Draft Northern Tier Specifications for HPWH (continued) Preliminary Draft Requirements: First hour rating no worse than electric resistance tank of similar volume Exhaust ducting capability Noise limit (35 db-a) Low temperature operation down to 35F Freeze Protection: cannot be damaged if exposed to below freezing temps for 24 hours. Condensate overflow shutoff switch Warranty 3 year parts and labor in addition to E- STAR 6 years on parts

14 Draft Northern Tier Specifications for HPWH: Next Steps 1. Work with Northern Tier HPWH Coalition to get agreement on minimum set of common requirements 2. Open dialogue with manufacturers 3. Discuss potential for common program structures and offerings.

15 Draft Northern Tier Specifications for HPWH Send comments to: Jeff Harris Director for Emerging Technology Northwest Energy Efficiency Alliance x253

16 Thank You!