Applications of energy piles and technical development of PCC energy piles

The energy pile is the combination of ground source heat pump technology and purposely designed pile for storing energy in the ground using buried pipes during hot climates and retrieving energy from it when it is needed. The technical principles, pile types, buried forms and economic advantages of the energy pile are introduced. The heat transfer pipes can be buried in drilled shaft, precast piles, steel piles and cement mixing piles. The current advances and research status of energy piles at home and abroad and their engineering applications(including drilled shafts and precast piles) in recent years are reviewed and summarized. Moreover, some major problems in engineering applications are revealed, leading to the development of a new PCC energy pile. The prospects of the PCC energy pile in the national energy saving projects of China are analyzed, and the further research orientation is proposed.