This study aims to describe the feasibility of exhaust thermal energy utilization by using the PCM transportation. This system demands the space to put in the PCM containers. Therefore the possibility of energy saving depends on how large space there is and how is the exhaust thermal energy used. In this paper, we examined the change of possibility in various patterns in DHC. As a result, we confirmed that the possibility of energy saving is expected most in the system that supplies the warm water.