Energy Efficiency Monitoring And Evaluation Of A Ground-coupled Heat Pump System

As a building energy saving technology, the ground source heat pump has been widely used in recent years in northern China. However, due to system design, running management, some practical engineering projects run at low efficiency. To monitor the operation of a large-scale vertical ground-coupled heat pump system in Tangshan, a data monitoring system was applied in this paper. A comprehensive understanding of the system’s operating performance and management condition was obtained through date analysis and field research.Based on data monitoring and field research, the operating effect, the operating performance and the management level was totally evaluated. The seasonal energy efficiency ratio was relatively low. The user thermal comfort satisfaction in cooling quarter and heating quarter are both below70%. Due to the difference of air conditioning load in summer and winter, the heat rejection was less than heat extraction from the ground source, and the unbalance ratio was15.13%. It was found that the system run at relatively low load in most operating time. The operation management was imperfect owing to the hydraulic imbalance and bypass phenomenon in unit water pipe.A unit running strategy was recommended according to the system operation feature. The variable primary flow chilled water system was chosen as the ideal alteration proposal. It is recommended that the night ventilation should be applied in the intermediate and late cooling season.