Performance assessment of ground-source heat pumps (GSHPs) in the Southwestern and Northwestern China: In situ measurement

Abstract

Ground-source heat pump (GSHP) systems contribute significantly to the reduction in energy consumption and CO2 emissions. The vast territory, abundant geothermal sources, and different climatic zones of Southwestern and Northwestern China provide significant opportunities for the application of GSHP technologies. In this study, a statistical study was performed to assess the general performances and identify the existing problems of GSHP systems located in the abovementioned areas. Twenty-eight GSHP projects, including groundwater heat pumps, soil-source heat pumps, and surface water heat pumps were selected. Water temperature, energy consumption, coefficient of performance (COP), energy efficiency ratio (EER), and thermodynamic perfectibility were analysed. The energy efficiency of GSHP systems were assessed according to the national standard. In addition, barriers and problems in GSHP applications are discussed herein. It is concluded that the average cooling COPs of SSHP, GWHP and SWHP units are 4.9, 4.7, and 4.2, respectively, with SSHP unit being the highest. The average heating COPs of SSHP, GWHP and SWHP units are 4.3, 4.2, and 4.2, respectively with SSHP unit being the highest. The SSHP has the best performance in both seasons amongst three GSHP types. Furthermore, though 89% of the systems can meet the requirements of national standard, more than 50% of them work at the lowest allowable energy efficiency value. This paper attempts to provide essential clues for the adoption feasibility and technical guidelines of GSHPs in the target areas.