18 May 2017

P.2.7.8 Development of Simulation Tool for the Shallow Ground Source Heat Pump System Using Vertical Spiral Ground Heat Exchangers and Its Application

The authors developed a simulation tool for the shallow ground source heat pump (GSHP) system using vertical spiral ground heat exchangers (VSGHEXs). In the simulation tool, the temperature variation caused by ground surface is superposed for the ground temperature calculation. The capacity resistance model is applied in order to consider the capacity of inside VSGHEX. In this paper, the outlines of the simulation tool are explained. Next, the simulation tool was validated by comparing with the value measured in the field experiment using the VSGHEXs. Additionally, the authors assumed that the shallow GSHP system using VSGHEXs is installed in the residential house and carried out the feasibility study. The number of VSGHEXs that can operate the shallow GSHP system over the long term was investigated in response to the residential house’s insulation performance and the region. Lifecycle cost (LCC) of the shallow GSHP system was calculated and compared to the conventional air source heat pump system.