Numerical Simulations of a Hybrid Geothermal Heat Pump System

Abstract

A hybrid geothermal heat pump (GHP) system and its monitoring system were installed at the SPOREX building in Korea Institute of Geoscience and Mineral Resources in Daejeon, Korea. This hybrid GHP system consists of a vertical closed-loop system that is connected to the second floor and an open-loop system that is connected to the third floor. Three wells (geothermal well, injection well, and monitoring well) were installed at the backyard of the SPOREX building. The reason that this GHP system is called hybrid is that the geothermal well consists of a single U-tube for the closed-loop system and well pump and production and reinjection pipe for the open-loop system. The advantages of this system are reduction in initial costs of installation and enhancement of the performance of the closed-loop system. Numerical simulations are performed to analyze the performance of each GHP system and thermal changes in the groundwater around the site.