20 September 2011
This paper describes the design concept of an energy efficient heat pump system
installed in a hospital in Chiba prefecture of Japan. Several kinds of heat pumps and thermal energy storage including Ground Source Heat Pump (GSHP) system were applied for
heating, cooling and hot water supply. The GSHP system is operated in heating mode at night time and in cooling mode at daytime during the summer season. This alternate
operation mode change is a short term heat storage system using the ground as thermal storage. By introducing short term alternate thermal energy storage operation, the efficiency of GSHP system which usually suffers from the performance degradation over long period due to the ground temperature rise is expected to improve. In this paper, applied heating and cooling system, soil conditions, operating concept, conceptual drawing are described followed by the performance analysis based on the actual operation data.