Status and Outlook for Research on Geothermal Heating Technology

Geothermal energy is widely used in building heating owing to its stability, large reserves, and wide distribution. Beginning from the classification of geothermal energy heating technology, this paper elaborates on the basic concepts, development history, and application status of shallow ground source heat pump technology, hydrothermal heating technology, and medium-deep borehole heat exchanger heating technology. Based on the reported research, future directions for investigation of geothermal energy heating technology are summarized, from the perspective of the operation mechanism and application practice. These future research directions mainly include heat balance analysis of large-scale shallow borehole heat exchanger arrays, high-efficiency water recharge technology of hydrothermal heating, and evaluation of the heat transfer performance of medium and deep borehole heat exchanger arrays.