Abstract
This paper analyzes the effectiveness of CGS for the CO_2 and cost reductions in the prospective distributed energy system, which is a future type system using heat pump for heating instead of boiler. The CGS effectiveness in different building types and regions are discussed, where COP dependencies on the ambient temperature and demands of heating or cooling are considered. The results show that CO_2 reduction effect of CGS in the prospective system is lower than that in the conventional system but the cost reduction effect is higher. It was also shown that the prospective CGS is more advantageous and appropriate in cold region.