Development and Challenges of Groundwater Heat Pump in China

A groundwater heat pump (GWHP) is one type of ground source heat pump (GSHP) and is a major form of earth energy utilization, which can realize the direct use of groundwater energy or the reuse of stored underground energy. The energy conservation effect of GWHP plays an important role in the national energy strategy, but the groundwater environment has been affected and even damaged to some extent because of over-exploitation and unreasonable utilization. This paper reviews the development and challenges of GWHP in China and surveys the situation of groundwater utilization, which shows that lack of cognitive ability, scientific constraints and reasonable utilization may bring catastrophic damage to the groundwater. A coming work should aim to more researching basic problems, such as thermal interaction, energy transport in the well field, groundwater contamination, etc. In fact, the characteristics of unsteady and transient heat transfer in the complex underground environment, and their control strategies have been being also the most pressing problem. Their explorations and studies will strengthen the theoretical and practical understanding, and guide an orderly, healthy and sustainable development of GWHP.