Demonstration and Assessment of Residential Gas Heat Pump Water Heaters in the Los Angeles Basin
This project will advance gas-fired heat pump water heaters by increasing operating efficiency and making it readily retrofitable.
The project is complete. The findings indicate that the GHPWH was able to save an average of 54% of total energy in the 5 residential demonstration homes. The GHPWH had an average CO2 emission reduction of 49%. Assuming a natural gas price of $1.00/therm and applying a 3% price escalation rate, these savings total $2,235 over a 10-year period for an individual home. A 10% market penetration of the gas heat pump water heater could yield annual natural gas savings of 90.9 million therms and a reduction of 482,000 metric tonnes of CO2 across California.
This project advanced the commercialization of residential gas heat pump water heaters (GHPWH). The GHPWH integrates a small, gas-fired, single-effect, absorption heat pump with a hot water storage tank. The project consisted of field demonstrations, extended-life laboratory testing, development of modeling tools, and stakeholder outreach events. Technology was tested at homes in the Los Angeles Basin, resulting in a 54% energy usage reduction, 49% CO2 reduction, and 4.5-8 year payback based on energy savings.
With an equipment cost comparable to condensing storage water heaters, the GHPWH shown an average savings of 54% compared to baseline water heaters through the test sites with a payback of between 3.4 and 8 years, based on energy savings.
The GHPWH uses water and ammonia, a natural refrigerant with zero global warming potential and zero ozone depletion potential. The GHPWH had an average CO2 emission reduction of 49% compared to baseline water heaters.
Key Project Members
ADM Associates, Inc.
Stone Mountain Technologies Inc.
Applied Research West
Frontier Energy, Inc.
Scott Harrison Plumbing