Refrigeration system using resources of the regional environment in the Oya area

Abstract

The Oya area of Utsunomiya City in Tochigi Prefecture is now with far less vitality than before owing to the decline of the Oya-stone industry, which used to be the main industry in the area. This decline is caused by a rise in new construction materials and overseas production materials. Despite the lack of vitality, the area is now showing signs of recovery. The local government recently tackled the Oya area revitalization by utilizing the abundant underground water of the Oya-stone quarry, which was once a facility of the Oya-stone industry. The quarry groundwater has an average water temperature lower than that of the ordinal groundwater. Business projects utilizing the quarry groundwater as a heat source for the heat exchange system have recently been promoted by the local government. Therefore, this study aims to explore the possibility of region revitalization by utilizing the regional resources in the Oya area by evaluating the proposed cooling system that makes use of the quarry groundwater as a heat source of the heat exchange system from the viewpoint of cooling performance. A food refrigeration system that uses the quarry groundwater as the heat source is prepared herein for measurement. The food refrigeration business will trigger the creation of work places in the Oya area, where the stone industry has deteriorated. The heat exchange amount of each element in the cooling system is identified from the measured temperature and humidity. The cooling performance is simulated and evaluated for several models that use cold water by utilizing the measured temperature and humidity as well as the identified heat exchange amount. This study demonstrates the concept of a groundwater cooling system that could be a way for region revitalization.