[S27-1] Geothermal energy: Ground source heat pump, hydrothermal system, and hot dry rocks

[S27-1-03] Alternative use of subsurface energy as heat pump or groundwater

^○Makoto Taniguchi¹, Hideki Hamamoto² (1.Research Institute for Humanity and Nature, Kyoto, Japan, 2.Center for Environmental Science in Saitama, Saitama, Japan)

invited

Thermal energy in subsurface environment can be used sustainably if we can manage the resources carefully. Demands for energy to melt snow accumulated on the roads is increasing in many coastal snowy areas in Japan. There are alternative uses of subsurface energy, and the one of them is the use of groundwater for melting snow, because the temperature of the groundwater is relatively higher in winter than that of the air and river water, therefore groundwater itself is a useful heat source to melt snow. Another way is the use of heat pump, which is the use of thermal energy in shallow subsurface for melting snow. In this study, the effects of alternative use of subsurface energy as heat pump or groundwater have been analyzed by three-dimensional groundwater flow model with subsurface thermal analyses in the snowy areas of Obama City, Fukui Prefecture, Japan.