In this paper, a new technique of Aquifer Thermal Energy Storage (ATES) system which can be applied to the urban areas effectively is proposed. It is aimed at using a shallow aquifer. The thermal storage process in an aquifer enclosed by the cut-off walls under the building is investigated. An experiment on short term cold storage was done in a central part of Tokyo. The efficiency of heat recovery of 80% or more was obtained at a diurnal cycle, and the sensitivity was analyzed by numerical simulations.
