Advantage of local energy matching and sharing towards zero carbon community

On-site energy management is one of the key strategies toward improving energy efficiency and reducing CO2 emissions in the building sector. The Japanese energy supply situation has changed drastically before and after the nuclear power plant accident in 2011 because the power plants operation has been restricted considering safety. Since the energy market prices and CO2 emission factors of electricity generation have changed, it is expected that the potentials of on-site energy management will also have changed. This article describes the potential for energy sharing between four different types of Japanese buildings with their own on-site combined-heat and power (CHP) energy generation, and models the performance of different scenarios considering CHP operation strategy, energy market price and CO2 emission factors. Comparison of primary energy consumption between individual and combined scenarios shows that the potential advantages of energy sharing are determined by the combinations of buildings and the CHP operation strategy. Moreover, if the CHP operational modes are optimised, then energy sharing provides greater advantages of reduced operation cost and CO2 emission under market conditions where the power supply configuration of the centralized generation is subject to change