Geothermal utilization system and geothermal utilization method

摘要

PROBLEM TO BE SOLVED: To provide an underground heat utilization system capable of simply managing balance of heat quantity of underground water through the year.SOLUTION: An underground heat utilization system 10 includes: a heat source well facility 80 having a hot water well 11, a cold water well 12, a well side pipe 20 and pumps 31, 32; a heat source machine 13 having a refrigeration cycle comprising a compressor, a condenser C, an expander, and an evaporator E; primary refrigeration circuits 14, 14' connected to one of the condenser C and evaporator E of the heat source machine 13, and capable of exchanging heat between the one and the well side pipe 20; secondary refrigerant circuit 15, 15' connected to the other one of the condenser C and evaporator E of the heat source machine 13, and capable of exchanging heat between the other one and a load 16; and a mode switching unit 17 configured to switch a mode between a cold storage operation mode in which the primary refrigerant circuit 14 is connected to the evaporator E and the secondary refrigerant circuit 15 is connected to the condenser C, and a cold radiation operation mode in which the primary refrigerant circuit 14 is connected to the connector C and the secondary refrigerant circuit 15 is connected to the evaporator E.SELECTED DRAWING: Figure 1