Taking a large public building in a hot summer and cold winter area as the research object, a simulation model of shallow medium deep geothermal cascade utilization coupled heating was built based on TRNSYS software. The operating characteristics of the shallow medium deep coupled heating system during the heating season were analyzed and compared with a single medium deep geothermal cascade utilization heating system and a shallow ground source heat pump system. The results show that the coupled system is superior to a single deep or shallow geothermal heating system in terms of end heat transfer, geothermal return water temperature, heat pump unit COP, and system energy utilization efficiency. The system is more stable and adaptable. The average energy utilization efficiency of the system reaches 0.95, verifying the feasibility of the coupled system operation.

middle deep geothermal energy  /  cascade utilization  /  geothermal heating  /  ground source heat pump  /  TRNSYS simulation  /  system energy efficiency