A review for the applications and integrated approaches of ground-coupled heat pump systems

During the past few decades, a large number of ground-coupled heat pump (GCHP) systems have been widely applied in various buildings around the world due to the attractive advantages of high efficiency and environmental friendliness. However, most buildings in warm-climate or cold-climate areas have unbalanced loads, dominated by either cooling loads or heating loads. Therefore, it is necessary to employ integrated approaches in the design of GCHP systems to decrease the initial cost of the GCHP systems and, at the same time, to improve the system performance. In this paper, the main integrated approaches of GCHP systems were summarized based on the available references and our experience. Then the suggestions were given. For a heating-dominated building, the combination of a GCHP system with a solar thermal system shows great potential for energy conservation and high-efficiency utilization of the GCHP system. With respect to a cooling-dominated building, the simplest approach is to integrate a GCHP system with a cooling tower although there are more available technologies. It is believed that the high inertia heating or cooling distribution systems such as radiant floors, ceilings or walls are more suitable for GCHP systems. It is highly suggested to establish optimal operational control strategies for integrated GCHP systems according to the climatic conditions, building functions and thermal balance of the ground.