Abstract
Thermal load of District Cooling and Heating was considered as an unconfirmed phenomenon. Thermal load was constituted of two phases. These were Short range fluctuating load in one week and Long range fluctuating load in one season. In this paper Short range fluctuating load was studied using the actual hourly operating data of one week in summer and winter to each building at Sapporo D. C. H. Plant. Consequently the concept of the diversity factor was obtained using the normal distribution curve for the fluctuating thermal load of each building. Furthermore, the proper thermal load of the piping network was gotten with multiplying the sum of each building's maximum hourly thermal load by the diversity factor of each pipe.
