Status of Geothermal Power Generation in Japan

Abstract

This report describes the geothermal power generation in five years from 1995 through 1999 in Japan. It also mentions the measures by the government for development and the international coordinations. Another report (Sekioka and Yoshii, 2000) deals with the direct geothermal use in this country. The installed geothermal generation capacity in Japan was 312.3MW as of 1 January 1995 (Yamaguchi et al., 1995). Yamagawa, Sumikawa and Yanaizu-Nishiyama geothermal power stations started operation in 1995. Ogiri, Kakkonda II and Takigami joined the line in 1996. A geothermal unit in Hachijojima started operation in March 1999. Thus, as of 1 January 2000, there are nineteen geothermal units at seventeen locations in Japan. The total installed capacity is 546.9MW, which is 0.2% of the power generation facility in Japan. The electricity produced by geothermal energy in fiscal 1998 (April 1998 -- March 1999) is 3,531.6GWh, which is 0.4% of the annual electricity produced during the corresponding period in Japan. Although Oguni is the only definite geothermal construction plan, government surveys prospective fields actively. In the five years, there was no drastic reform on geothermal power plants. However, solid betterment took place. Two units have equipped hydrogen sulfide (H2S) abatement system for further environmental protection. Scale prevention systems have been installed for some plants. Operators reexamined the whole system to make the most of the reservoir by minimum modification of the facilities. Geothermal development involves uncertainty and requires substantial pre-investment; and advanced technology is necessary, especially for survey. Thus government and other institutions provide technical and financial assistance. Geothermal discharges less CO2 and will be more necessary in the next century. Japan is to apply its knowledge, obtained through domestic development, to contribute to the world.