Since the Okinawa islands are surrounded by the sea in all directions, the source of supply of electric power in the distant islands are mainly diesel electricity power. Therefore, an electric power of unit price is expensive than coal thermal power generation. The electric power generation system by wind energy has an extreme advantage in the viewpoint of clean energy. In this research, we investigate the possibility of installing in the offshore-type wind turbine system. Furthermore, the effect of the amount of carbon dioxide reduction are evaluated