Abstract
In this study the energy performance data of District Heating and Cooling (DHC) plants all over Japan are analyzed with factor analysis and multiple regression analysis in order to verify statistically the factors that effect energy efficiency of DHC plants. In addition, the evaluation methods of Co-Generation System (CGS) are examined to reveal how the discrepancy in the definition of waste heat value from CGS affects energy efficiency. The results lead to the following three conclusions. 1. The operation of heat source equipment is an important factor in all systems. 2. The heat load characteristic affects energy efficiency especially in plants which uses gas as main energy source. 3. The energy efficiency of plants utilizing CGS varies greatly according to evaluation method and actual operation condition of CGS.
