Abstract
The development of a system containing renewable energy for local production and local consumption is a very important research issue, 丘om environmental and safety points of view. As an example of this type of research, in order to develop a system for local production and I ocal consumption, a study about the utilization of large amounts 'of renewable energy was performed at Kitami City, Hokkaido. First of all, the exploitable renewable energy sources in the city are found to be tidal, wind and solar generations. However, for the maχimum utilization of these resources, energy storage systems or controllable power generators are necessary. In orderto supply the whole Kitami City's power demand, a system containing wind, tidal and solar power generation together with sodium-sulfur (NaS) batteries is developed and presented in this work. Because Kitami city has the particularity that is located ina very cold region and that the demand during winter is big and that of summer small, this paper proposes a seasonal energyshifting method, 丘om summer to winter, taking into account economic and environmental aspects. Results show that, compared toconventional systems, environmental impact is reduced to about 1/6, but the total cost increases about 6 times.
