Electric load levelling is one of the urgent requirements for the utility power industries in Japan. As a solution to this requirement, the intensive heat storage system utilizing surplus power during off-peak hours at nighttime was chosen for heating rooms and water supply in buildings, such as hotels and hospitals. This paper describes the system construction and the comparison of the analysis with the experiment on the 2300MJ solid material sensible heat storage system. The analysis considering heat loss predicted the variations of the air and brick temperatures in good accuracy in both charge and discharge processes. The effectiveness of the storage material is also discussed.
