A Review on the Thermal Imbalance in Soils Due to Geothermal Energy Piles and Potential Solutions to Improve Their Efficiency
摘要
To meet the increasing energy demands for indoor temperature regulation, geothermal energy has been extensively employed due to its environmental benefits, cost-effectiveness, and sustainability. This energy is harnessed from shallow and deep ground sources using ground-source heat pump (GSHP) systems. Geothermal energy piles, which function as ground heat exchangers (GHEs), serve dual roles in terms of supporting structural loads and in addition to facilitating heat exchange between buildings and the earth. However, prolonged operation of these piles has led to thermal imbalances in the soil, particularly when used predominantly for cooling, resulting in performance degradation and reduced efficiency over time. This paper presents a comprehensive review of thermal imbalances in soil induced by geothermal energy piles. It examines various GSHP operational scenarios where thermal imbalances occur and investigates potential causes, such as exclusive use for cooling or heating. Furthermore, the paper discusses strategies to enhance the efficiency of geothermal energy piles, including modifications to GHE configurations and the integration of GSHPs with other energy sources, to effectively mitigate underground thermal imbalances.