Evaluation of the performance of a hybrid cooling/heating system combining groundwater direct cooling with groundwater heat pump for rural buildings

Abstract

With the remarkable improvement of villagers' living standard and the requirement of building energy efficiency, it becomes imperative to rely on renewable sources of energy and make a more efficient use of energy to solve the problem of cooling/heating for the rural buildings. This paper presents a new hybrid cooling/heating system, which combines groundwater direct cooling system (GWDCs) with groundwater heat pump system (GWHPs). The system is installed in an office building in Youhao Street, Duliu town, Jinghaicounty, Tianjin, China. The feasibility of the system is verified and the performance of the system is experimentally evaluated both in cooling and heating modes. It is found that the average GWDCs COPS is approximately 3.85 in the cooling season, while the average heat pump COP and the overall system's COPS of GWHPs are about 5.05 and 2.8 respectively. The results obtained from the experiment show that these systems could be used safely, reliably and efficiently at the lowest cost for the rural buildings in Tianjin, China.