Most buildings in the cold climate zone have unbalanced loads, mainly dominated by heating loads. The cold buildup within the soil would definitely reduce the soil temperature, which could consequently disturb the soil temperature balance, and furthermore, deteriorate the performance of ground source heat pump. A hybrid ground-source heat pump (HGSHP) with auxiliary heat source could be proposed to solve this problem. The paper aimed at investigating the feasibility and performance of HGSHP in Shenyang located in the cold area. Firstly, hourly dynamic loads of one office building were calculated. Then, three systems, including one HGSHP system with boiler as auxiliary heat source, ground source heat pump system (GSHP), and a traditional electric water chiller + boiler system (WB) were designed and simulated for this office building by TRNSYS. Several performance parameters for these three systems were obtained. These parameters included the hourly outlet/inlet temperature of buried pipes, hourly soil temperature, energy consumption distribution and the coefficient of performance (COP). Simulation results indicated that HGSHP system with boiler as auxiliary heat source could effectively solve cold accumulation problem and reduce traditional energy consumption. These results could provide some reference on HGSHP system utilization in the cold climate zones of China.
Zhijian Liu, Wei Xu, Xue Zhai