Idemitsu Kosan Co. recently began commercial operation of the 5-MW Takigami binary geothermal power plant in southern Japan.
Japan has about 10 percent of the world’s geothermal resources, and has the third highest potential for geothermal power in the world, according to the company.
Idemitsu said that, since the start of operation of the Takigami Power Station of Kyushu Electric Power Co. in 1996, the Takigami Office of Idemitsu Oita Geothermal Co. has supplied steam used to generate power.
The company began construction last year on the binary power plant in order to put unused hot water to use. The plant uses two fluids — hot water and a medium that has a low boiling point — for power generation. Idemitsu said that this method makes it possible to generate power using low-temperature steam and hot water that could not be used in traditional geothermal power generation.
The Takigami binary plant will have annual generation of 31 million kWh, according to the company.