Analysis of Heat Accommodation Effect in District Heating and Cooling Systems

The purpose of this research is to investigate a method to improve the efficiency of heat source systems in two buildings by heat accommodation of cold/hot water between two facilities, and to clarify the energy saving effect. In this report, measured value analysis and simulation on the representative days are carried out. Heat source systems in two buildings located east and west across a road are targeted as the east district system and west district system. Overall, the equipment in the west area has better performance. First, the heat accommodation effect was verified by a measured values analysis. The analysis was carried out by comparing the representative days. Improvement of the east district SCOP was seen when remitting cold heat from the east district to the west district. In addition, it was confirmed that the heat recovery heat pump was operated by remitting hot water from the west district to the east district, and total SCOP of both districts improved. Next, efficiency is analyzed using a simulation model. We conducted a simulation to shift the load of each district and examined effective heat accommodation control. As a result of the simulation on the representative day, by remitting the load in the west district to the east district during the night and remitting the load in the east district to the west district during the day, heat recovery heat pump in the west district operated more, and the total SCOP of both districts improved. Examination by the measured value analysis and simulation showed that control to operate heat recovery heat pumps in the west area more is effective.