The coupling of photovoltaic-thermal utilization and ground source heat pump is expected to use photovoltaic waste heat to avoid performance degradation of the heat pump

and also to use photovoltaic electricity to partially meet the energy demand of the heat pump

which has a broad prospect. A simulation model of the integrated system of low-concentration photovoltaic-thermal and ground source heat pump is constructed

and the operational performance of the system is analyzed. Moreover

the key influence laws of the life cycle cost of the system are also analyzed. The research results show that

the annual solar-to-electrical efficiency of the integrated system reaches 17.73%

which is 9.58% higher than that of the single operation system. The photovoltaic waste heat of the photovoltaic-thermal device can effectively reduce the soil temperature decay

and the long-term operation performance of the heat pump is 16.58% higher than that of the reference system. The operation and maintenance cost of the system decreases with the increase of the scale of the photovoltaic-thermal device and the ground source heat pump

while the investment cost increases accordingly. The total life cycle cost of the system decreases at first and then increases with the increase of the scale. Taking the life cycle cost as the objective function

economic optimization of the system based on the particle swarm algorithm is carried out

and the life cycle cost reduces by 31.52% compared with the design of the maximum scale capacity. The relevant results can provide theoretical reference for optimal design of the photovoltaic-thermal-ground source heat pump integrated system.