Abstract
In order to reduce energy consumption, we designed and build an office building with natural ventilation and night purge system in Tokyo, and tried to evaluate energy conservation effects of this building. First, we evaluated the effects by numerical analysis at planning stage. The results of analysis indicated that it is possible to reduce about 60% of daily energy consumption for air-conditioning system in an intermediate period by using natural ventilation and night purge system. Especially, when the air-conditioning system started, it is able to reduce air-conditioning load by the effect of cool thermal storage by night purge. Next, we carried out measurements in this building at the operating. From the results of measurements, the energy conservation effects were able to be confirmed almost the same of that of numerical analysis. In addition, the amount of energy reduction by natural utilization system including the directly cooling system by outdoor air, possibly equal to 80% of daily air-conditioning load. Those results show that the natural utilization system is very effective for energy saving.
