IIR document

Progress in ground-source heat pumps using natural refrigerants.

Author(s) : WU W., SKYE H. M.

Type of article: Article, IJR article, Review


Natural refrigerants are attractive candidates for replacing the high Global-Warming-Potential fluorinated refrigerants used in ground-source heat pumps (GSHPs). This paper presents a comprehensive survey on GSHPs using CO2, NH3, water, and hydrocarbons. We compared the refrigerants’ thermodynamic properties, analyzed their performance in brine-to-air and brine-to-water GSHPs, and discussed recent progress in their use in GSHPs. Studies of CO2 were the most common due to its favorable properties, covering advanced cycles, direct-expansion, secondary fluid, and hybrid GSHPs. Though with toxicity concerns, NH3 was the second most studied, including vapor-compression GSHPs for heating, absorption-type GSHPs to eliminate ground imbalance, and hybrid compression-absorption GSHPs to widen the operating temperature range. A few studies evaluated water as a refrigerant for absorption-type GSHPs, including applications for solar cooling, ground imbalance, and district heating. Propane was the only hydrocarbon considered for GSHPs, including analyses on refrigerant charge, performance analysis, and propane as a secondary fluid..

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Pages: 70-85


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  • Original title: Progress in ground-source heat pumps using natural refrigerants.
  • Record ID : 30024289
  • Languages: English
  • Source: International Journal of Refrigeration - Revue Internationale du Froid - vol. 92
  • Publication date: 2018/08
  • DOI: http://dx.doi.org/10.1016/j.ijrefrig.2018.05.028


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