Performance evaluation of a ground source heat pump system in India using experimental and modeling approach

This research explores the effectiveness of a Ground Source Heat Pump (GSHP) system for cooling purposes in Indian conditions. Key parameters considered include the water’s flow rate, grout material, run time, return air temperature, and borehole configuration. A series of trials were conducted to review the system’s cooling effectiveness by employing two types of grout materials, construction, and demolition (C&D) waste, and the surrounding soil in four distinct borehole layouts. A linear regression model was used to assess how critical factors affected the system’s efficiency for each type of grout. An analysis of variance was also performed to determine which factors had the most significant impact. The study found that factors such as borehole length, system efficiency, and thermal characteristics significantly influenced the GSHP system's thermal performance. The findings revealed that the Coefficient of Performance (COP) of the heat pump and the overall system increased with the number of boreholes and volumetric flow rate. At the same time, it decreased with the rise in initial air temperature and extended operation run time. The mean COP for the GSHP arrangement utilized in thermal management with C&D waste as grout material was determined to be 8.1% lower than the value achieved when using the surrounding soil as the grout material. The results signify that utilizing a GSHP arrangement has the potential to be a favorable choice for cooling purposes. The system is effective, offering considerable energy savings compared to traditional air-conditioning systems. Nevertheless, the effectiveness of the system is determined by various elements, such as the length of the borehole, overall system efficiency, and thermal properties. Therefore, it is vital to carefully consider these factors when designing and installing a GSHP system.