Development of Environmentally Benign Heat Pump Water Heaters for the US Market

Conference · Sun Jan 01 04:00:00 EST 2012

OSTI ID:1049818

Abdelaziz, Omar ^[1]; Wang, Kai ^[1]; Vineyard, Edward Allan ^[1]; Roetker, Jack ^[2]

---

1. ORNL
2. General Electric - Appliance Park

Improving energy efficiency in water heating applications is important to the nation's energy strategies. Water heating in residential and commercial buildings accounts for about 10% of U.S. buildings energy consumption. Heat pump water heating (HPWH) technology is a significant breakthrough in energy efficiency, as an alternative to electric resistance water heating. Heat pump technology has shown acceptable payback period with proper incentives and successful market penetration is emerging. However, current HPWH require the use of refrigerants with high Global Warming Potential (GWP). Furthermore, current system designs depend greatly on the backup resistance heaters when the ambient temperature is below freezing or when hot water demand increases. Finally, the performance of current HPWH technology degrades greatly as the water set point temperature exceeds 330 K. This paper presents the potential for carbon dioxide, CO2, as a natural, environmentally benign alternative refrigerant for HPWH technology. In this paper, we first describe the system design, implications and opportunities of operating a transcritical cycle. Next, a prototype CO2 HPWH design featuring flexible component evaluation capability is described. The experimental setup and results are then illustrated followed by a brief discussion on the measured system performance. The paper ends with conclusions and recommendations for the development of CO2 heat pump water heating technology suitable for the U.S. market.

• Research Organization: Oak Ridge National Laboratory (ORNL); Building Technologies Research and Integration Center
• Sponsoring Organization: EE USDOE - Office of Energy Efficiency and Renewable Energy (EE)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 1049818
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
AMBIENT TEMPERATURE
CARBON DIOXIDE
CO2
COMMERCIAL BUILDINGS
DESIGN
ENERGY CONSUMPTION
ENERGY EFFICIENCY
EVALUATION
FREEZING
GREENHOUSE EFFECT
HEAT PUMPS
HEATERS
HOT WATER
Heat Pump Water Heater
MARKET
PAYBACK PERIOD
PERFORMANCE
REFRIGERANTS
Transcritical
WATER HEATERS
WATER HEATING