SET Proceedings 2978-4387 Caravel Press 10.65582/set.2007.024 2007.024 Investigation on the Operating Performance of Hybrid Ground Coupled Heat Pump Systems: a Case Study in Hong Kong CuiPing ping.cui@polyu.edu.hk YangHongxing FangZhaohong Renewable Energy Research Group, The Hong Kong Polytechnic University, Hong Kong, China Shandong Architecture University, Jinan, China 05092007 6 1 978-1-995850-09-2 146 152 5 September 2007 © 2007 Copyright WSSET 2007

A pilot project of the hybrid ground-coupled heat pump (HGCHP) system with hot water supply reported in this paper was developed in October, 2006 in Hong Kong for research purposes. The HGCHP system can offer space cooling and/or space heating accompanied with hot water supply for residential or public buildings. A data collection system was established to record most of the operating variables. The operating performance has been discussed and evaluated based on the recorded data. Furthermore, the impact of the heat transfer within the ground heat exchanger on the surrounding soil has been discussed according to the recorded temperatures within the boreholes. The results demonstrate that this system has higher energy efficiency for providing space cooling and hot water. The experiments also indicate that the alternative cooling/heating modes and discontinuous operation are favorable for the heat transfer process in the ground heat exchangers. Therefore, the HGCHP system with DHW supply is a preferable alternative for hot-climate areas like Hong Kong when space cooling and DHW are needed at the same time.

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