A chilled-water thermal energy storage system in a high rise building

This case study described a thermal energy storage system serving for a high-rise building. A multi-connected chilled-water storage tank was employed in an 11-story building in Oita, Japan. The HVAC system is distinguished from the traditional by two characteristics. One was its high water temperature differential (10K) in the tank, the other was its higher supply water temperature (10°C) of load side. The lowest/highest water temperature in the tank was 7/17°C. We named this system as a thermal storage system with high temperature differential. The system realized a decrease in yearly energy cost and cut down its daytime peak electricity demand. On the other hand, the higher supply water temperature was worried because the coiling coils might suffer from unfavorably with its dehumidifying ability. Under the foundation of two years' general performance experience, we planned three experiments and put them into practice in 1999 summer to test more economically design/performance of such a system. The results of these experiments were presented in this paper.