| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance energy efficiency of a hot water storage type water heater. <P>SOLUTION: The hot water storage type water heater includes a used heat amount calculator (S30) calculating the heat amount of hot water taken out from a hot water storage tank and used, a target heat amount calculator (S32) calculating a target heat amount to be stored in the hot water storage tank at that day on the basis of recording of used heat amount for past several days, a night rate storage unit storing night rates to be a rate of a heat amount to be stored in a prescribed night time in which an electricity unit price is set relatively low, a night target heat amount calculator (S34) calculating night target heat amount by multiplying the target heat amount calculated by the target heat amount calculator by the night rate, and a heating operation controller controlling heating operation of a heater. The heating operation controller controls the heating operation of the heater so that night target heat amount calculated by the night target heat amount calculator is stored in the hot water storage tank during the night time (S35 to S43). <P>COPYRIGHT: (C)2012,JPO&INPIT |
