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Accession Number DE2013-1049818
Title Development of Environmentally Benign Heat Pump Water Heaters for the US Market.
Publication Date 2013
Media Count 12p
Personal Author E. A. Vineyard J. Roetker K. Wang O. Abdelaziz
Abstract 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.
Keywords Buildings
Energy consumption
Energy efficiency
Heat pump water heater(HPWH)
Heat pumps
Water heaters

Source Agency Technical Information Center Oak Ridge Tennessee
NTIS Subject Category 97J - Heating & Cooling Systems
97G - Policies, Regulations & Studies
Corporate Author Oak Ridge National Lab., TN.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1326
Contract Number DE-AC05-00OR22725

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