Heat pump water heater or reverse cycle chiller designed for use in commercial kitchens.
Heat pump water heaters that provide up to 160 degree water are now available. Commercial kitchens typically have booster heaters in their dishwashers to electrically boost the temperature from 120 degrees to 140 degrees. This hot water demand can be accomplished more efficiently with heat pump technology. Conservative energy savings for hot water are on the order of 20%.
The heat pump technology removes heat from the air in the space where the water heater is located, and transfers that heat to the water via a refrigeration circuit. A side benefit is that this provides some 'free' cooling to the space.
This technology could also be considered for other high water use occupancies, such as nursing homes, apartments, and hotels. With the introduction of the 160 degree models, this technology could replace all electric resistance water heaters. A careful design balancing the recovery rate with storage capacity is required.
Status:
Baseline Description: Electric Boost Water Heater for Dishwashers Baseline Energy Use: 0 kWh per year per square foot
Most commercial building hot water heat would be accomplished by natural gas. Only the use of heat pumps to replace electric boost water heaters in dishwashers would provide regional electrical energy savings. This is something that can be incentivized when dishwashers reach their end-of-life and require replacement.
"Typical" Savings: 60% Savings Range: From 50% to 70%
There are new products introduced all the time. GE states 62% over standard electric.Rheem states 50%
"Typical" Savings: 50% Low and High Energy Savings: 20% to 70% Energy Savings Reliability: 4 - Extensive Assessment
For an natural gas water heater with an energy factor of about 0.7 and a heat pump water heater with an energy factor of about 1.5, the energy (not electrical energy) savings would be about 50%.
Energy Use of an Emerging Technology is based upon the following algorithm. Baseline Energy Use - (Baseline Energy Use * Best Estimate of Energy Savings (either Typical savings OR the high range of savings.))
Simple payback, new construction (years): N/A
Simple payback, retrofit (years): N/A
Cost Effectiveness is calculated using baseline energy use, best estimate of typical energy savings, and first cost. It does not account for factors such as impacts on O&M costs (which could be significant if product life is greatly extended) or savings of non-electric fuels such as natural gas. Actual overall cost effectiveness could be significantly different based on these other factors.
ASHRAE, 10/01/2009. Standard Benchmark Energy Utilization Index ASHRAE
Greg Wilson, 05/17/2010. Heat Pump Water Heaters Applied to Commercial Kitchens AO Smith
H.M. Sachs, 01/01/2002. Toward Market Transformation: Commercial Heat Pump Water Heaters for the New York Energy $mart Program American Council for an Energy-Efficient Economy
Karl Johnson, 04/13/2009. Applications of Commercial Heat Pump Water Heaters in Hot, Humid Climates Electric Power Research Institute
WSU EEP, 12/17/2013. Energy Experts Q&A: Capture Waste Heat Washington State University Extension Energy Program