Thermal Analysis of UTES for Efficient Heating and Cooling for Buildings

The building sector accounts for about 40% of the total energy use. However, at the same time the building sector has a cost-effective saving potential of up to 80%, which can be effected over the next 40 years. A variety of TES techniques for heating and cooling applications have been done. To overcome this problem, we can use underground reservoir such as aquifer thermal energy storage and borehole thermal energy storage. The use of Thermal Energy Storage (TES) in buildings in combination with space heating, domestic hot water and space cooling has recently received much attention. Underground Thermal Energy Storage (UTES) systems allow the direct application of the earth energy in a form of heat that can be recovered and exploited by humans. As they are both economically competitive and environmentally friendly, UTES systems have gained increasing acceptance. So far, most UTES systems have been applied in cold and temperate regions for both heating and cooling. The aim of this study to propose an advantageous operation mode for the underground thermal energy storage (UTES) by reformatting the ground temperature distribution, and clarify the effects of an actual application. In general there were four typical operation modes, such as uniform mode, concentrative mode, intermittent mode and heat shield mode, which based on the different load allotment. Considering the heat treatment mode that usually give rise of temperature on the area apron and will shape an isothermal vertical wall to block heat flowing.