jaue2015008: Measurement survey on the thermal environment of under-floor earth tubes in summer

Abstract

A passive system is attracting attention as an environmental measure in the construction field. At present, there is growing demand for a passive energy system for environmentally friendly houses. In this research, the authors use a system that applies an earth tube, which has been distributed as a new passive energy system for reducing the cost for air-conditioning and CO2 emissions. In this research, the authors measure indoor temperature when the earth tube is operated in the summer season, ambient air temperature, and the temperature inside the under-floor earth tube; study its effect of reducing indoor temperature; and discuss its effectiveness. As a result, when the fans are activated while outdoor air temperature is low, the indoor is heated, but the heat storage unit is cooled at the same time. By using these functions separately, it would be possible to utilize them effectively. And when the fans were operated, the temperature at the outlet became lower than the temperature at the inlet. Form this, it was found that there are no problems with the earth tube’s function to cool air, but the effect of decreasing indoor temperature was slight.