Abstract
Hot water occupies one third of total residential energy consumption in Japan. Development of high efficient hot water system is strongly needed, but it is known that its real efficiency depends on actual usage. In this paper, hot water consumption was measured in 74 houses, and analyzed especially about average volume and seasonal, daily fluctuation. The followings are main result. 1. Daily average volume (40deg) is 186.8 L in 1 person household, 267.4 L in 2,399.4 L in 3,446.9 L in 4. 2. Daily fluctuation might be approximated by "Normal distribution" and "Gamma distribution" in many houses. 3. Degree of Seasonal fluctuation varies in houses. These results might be useful for development of high efficient hot water heaters and new test standard for its efficiency.
