Investigation of the effect of using various HFC refrigerants in geothermal heat pump with residential heating applications

摘要

In the present investigation, the impact of various refrigerants on the efficiency of the geothermal heat pump operation is investigated. Appropriate working range of five HFC refrigerants such as R125, R134A, R404A, R407C, and R507A for using a geothermal heat pump is studied. Also, the energy and exergy analysis is used to investigate the influence of varying temperatures of the exhaust fluid from the geothermal source on heat pump operation. The critical parameters, such as coefficient of performance (COP), exergy efficiency, and exergy destruction for various components, are calculated. The results show that, in the geothermal heat pump cycle, R134A and R125 refrigerants have the highest and lowest COP and exergy efficiency, respectively. Moreover, enhancing the temperature of the exhaust fluid from the geothermal source results in an enhancement of the COP. For the mentioned refrigerants, the exergy destruction due to the compressor, as the primary energy-consuming equipment, is obtained between 26.7 and 27.3% range relative due to the overall system. The outcomes achieved in present research may provide the instructions for the design and optimization of efficient geothermal heat pump systems.