Optimum Design of a Space Heating System Using Heat Pump Combined with Downhole Heat Exchanger

Abstract

Downhole Heat Exchangers (DHEs) in the previous applications were often installed in a shallow geothermal well, and they can stand for a moderate heating duty alone without any assistant heating facilities. However, due to the limitation of shallow geothermal resources, DHEs are still not prevalent worldwide. This paper proposes an idea for using DHEs together with a heat pump system, and gives a thermal performance analysis by combining the two sets together for space heating. We have theoretically analyzed the heating performance of the whole system with various configurations in order to get a maximum heat output. It is believed that these results could be helpful for extending the uses of DHEs in places where have not a high geothermal gradient.