Geothermal resources are a type of green energy, primarily utilized in buildings for cooling and heating through heat pump systems. However, heat pump systems all face the challenges of high operating energy consumption and cost. In this study, in order to solve the problem of the high total energy consumption of compressors and pumps in traditional ground source heat pump systems, a new ground source heat pump system with coupled evaporative condensers (EC-GSHP) is proposed, and a calculation model was built to compare and analyze its comprehensive performance compared with a traditional ground source heat pump in different climate environments. It was concluded that in a region with balanced cooling and heating loads, the energy consumption was reduced by 48.48 kW, the cooling energy saving coefficient (CESC) was 21.09%, and the comprehensive coefficient of performance (COP) increased by 1.31. In a region where the total cooling load was greater than the total heating load, the energy consumption was reduced by 105.19 kW, the CESC was 22.98%, and the comprehensive COP increased by 1.49. In a region where the total heating load was greater than the total cooling load, the energy consumption was reduced by 47.77 kW, the CESC was 21.41%, and the comprehensive COP increased by 1.30. It can be seen that the cooling and energy saving performance of the EC-GSHP system is significantly better than that of a traditional GSHP.

The compressor in the heat pump is crucial for efficient geothermal energy utilization, but faces challenges in optimizing energy efficiency, especially under variable working conditions. This paper investigates the complex energy characteristics of the R134a refrigerant in centrifugal compressors using CFD, combining entropy generation and relative energy rotor enthalpy to analyze energy conversion theory. Key factors such as temperature and pressure are fully considered. The results indicate that energy loss in centrifugal compressors mainly occurs in the gap between the blade top and near the tongue, with a vortex tendency at the impeller’s tail edge. As the flow rate increases from 1.2 kg/s to 1.45 kg/s, the maximum total entropy generation in the impeller decreases by 161%, and the rotor enthalpy minimum value increases by about 90%. This energy conversion analysis method can identify changes in the location and extent of energy loss, offering a new perspective for optimizing the structure and energy-saving design of centrifugal impellers.