Study on solar-ground source heat pump and combined heating system in severe cold area

Abstract

Abstract This paper studies the operation strategy and economy of solar-ground source heat pump gas heating system in severe cold region. Two operation modes of the system are introduced: series operation and parallel operation, and the two operation modes are simulated. This paper compares and analyses the heat exchange of the ground pipe, the change of the water temperature at the inlet and outlet of the ground pipe heat exchanger, the heating efficiency coefficient cop and the refrigeration efficiency coefficient EER of the heat pump unit during the five-year operation of the combined heating system, and studies the change of the soil temperature, Finally, the economic analysis is made from the initial investment cost and operation cost of two different heating schemes. The results show that the maximum heat transfer efficiency of the parallel system is 2.5 times that of the serial system, and the total heat transfer between the parallel system and the heat network is 83.2 % higher than that of the serial system. The inlet and outlet water temperature of the buried pipe decreased under both operation modes. After five years of operation, although the operation cost of the parallel combined heating system is higher than that of the serial combined heating system, the parallel combined heating system has more advantages than the serial combined heating system in terms of the overall heating effect of the system and the influence degree of the system on soil temperature.