抄録
In this report, possibility of the hot water supply energy reduction was examined based on survey investigation and the questionnaire survey. As a result, it was shown that hot water consumption nearly 20% might be reduced by changing behavior patterns or using the saving appliance. In the next, as a result of rough estimate of the efficiency of hot water heater, it was shown that the efficiency was low in a senior citizen household. It was also shown that the efficiency was improved by reducing invalid short-time use of hot water supply.
