Development of District Energy Supply System for CHP Implementation

Panel: Panel 9. Efficient Buildings in Efficient Communities

Authors:
Y. Yamaguchi, Osaka University
Y. Shimoda, Osaka University
M. Mizuno, Osaka University

Abstract

Advancement in the Combined Heat and Power (CHP) technology and the liberalization of the electricity market could contribute to realize various types of energy systems in a district. Thus, innovative energy efficient systems can be designed thorough comparison among available alternatives. However, most communities have no long term plan to improve the energy efficiency of existing districts. As a result, the potential energy saving that can be achieved by installing advanced district scale energy systems is abandoned due to difficulties to set up district scale heat delivery systems.

This paper suggests a process to install district scale CHP systems (District CHP) that could overcome the installation obstacles. In this process, combination of buildings starts within a few buildings. Thus, a number of small district CHP systems for two or three buildings are placed in a district. Finally, a large district CHP system integrates these subsystems.

This paper compares CHP implementation strategies to install District CHP and CHP for individual buildings (Individual CHP) by applying a bottom-up type district energy system simulation model for the Yodoyabashi district in Osaka, Japan. In this district, the District CHP strategy can achieve two times energy saving compared with the Individual CHP strategy. However, districts have to be carefully selected to implement the District CHP strategy, as the economical feasibility is heavily dependent on the arrangement and sizes of buildings. For densely developed existing districts, the District CHP strategy can be a promising plan to improve the overall community energy efficiency.