Results of an in-situ measurement campaign on a direct expansion geothermal heat pump with vertical drillings

摘要

Heat pumps are increasingly applied in the new renewable energy landscape. However, there is a large variation on the performance of heat pumps. This paper discusses the performance of a newly developed direct expansion geothermal heat pump with vertical drillings, using measurement results of an entire year. The heat pump was used for space heating and domestic hot water supply in a typical residential building in Flanders, the northern part of Belgium. The heat pump showed a good performance with a coefficient of performance (COP) for space heating and domestic hot water supply of respectively 5.11 and 3.06. The COP for space heating could be compared with the reference COP for geothermal heat pumps with vertical drillings which is 4.5. The higher COP of the direct expansion heat pump is due to the absence of the additional water heat exchange step inherent with a water source system.