A hybrid GSHP operating strategy to mitigate ground temperature variations in borehole heat exchangers

초록

The impact of load imbalance and thermal interference on ground source heat pump (GSHP) performance is significant, necessitating an appropriate design to address these challenges. Accordingly, various operational strategies utilizing hybrid heat sources have been studied in recent years. However, these approaches are exclusively based on parallel operation and fail to address overheating and overcooling issues in specific borehole heat exchangers (BHEs) under conditions of severe load imbalance. In this study, a group/individual operation strategy was proposed instead of parallel operation, where the peripheral BHEs handle the heating and cooling loads, while the central BHE, which experiences the most severe thermal interference, is dedicated to managing the domestic hot water (DHW) load. A 20-year simulation revealed that the group/individual operation strategy resulted in an average entering water temperature (EWT) of the BHEs that was approximately 1.03°C lower than that of the parallel operation strategy. Furthermore, the same number of BHEs could be utilized to additionally handle the DHW load, leading to enhanced system efficiency and utilization. © 2025 Building Simulation Conference Proceedings. All rights reserved.