Modelling of a large vertical ground heat exchanger integrated with a heat pump for building energy simulation in China

Abstract

Vertical ground coupled heat pump (GCHP) systems used in buildings in China can help to increase the share of renewable energy and improve the energy efficiency. A building energy simulation (BES) tool including a vertical GCHP model is beneficial for analysing the system performance under dynamic building loads. This paper presents a large-scale vertical ground heat exchanger model integrated to a heat pump model in the BES tool COMFIE, in a Matlab-Delphi co-environment. This model was applied to a residential building block with a 26 × 26 borehole field in Wuhan, China. The heat pump performance improvement was investigated for different design parameters. For half-hourly simulation of 1 year, the specific calculation time of the proposed GCHP model is 4 seconds out of 8 minutes for the whole building. The proposed model can be used as a design aid to optimise the system performance.