Performance analysis of solar-assisted ground source heat pump in severe cold regions

Long-term operation of a ground source heat pump (GSHP) in severe cold regions leads to a gradual decrease in subsurface soil temperature, affecting system performance. This paper proposes a solar assisted ground source heat pump (SAGSHP) system consisting of solar photovoltaic thermal (PV/T) and GSHP. Through TRNSYS software, the system was analyzed for 10 years of dynamic simulation in a severe cold region. The results are listed below: (1) The SAGSHP system is capable of effectively lessening the maximal temperature of photovoltaic (PV) modules in Changchun, Shenyang, and Harbin, China, by 21.73%, 13.67%, and 19.10%, respectively. The power generation efficiency of PV modules in these three locations can be maintained at about 22% year-round. (2) After ten years of operation, the coefficients of performance (COP) of the heat pumps have increased by 5.70%, 6.80%, and 5.01%, respectively, relative to the first year, showing good stability. (3) The soil temperatures at all three locations were stabilized during the ten years of operation. This study provides a theoretical basis for devising and installing SAGSHP in severe cold regions.