Geothermal power generation is roughly categorized into two methods.
Flash: A method of generating electricity by turning a turbine by the force of high-temperature steam coming out of the ground. It has been commonly used in geothermal power generation in Japan. It is suitable for geothermal power plants with high output, but since it requires high temperatures and large amounts of heat resources, careful development is required, and a long period of time is required before operation begins.
Binary: When the temperature of steam and hot water from the ground is low, a binary method is used to evaporate a medium with a lower boiling point than water and turn the turbine. The binary method can be developed by new drilling, and the construction of power plants can also be done using existing hot spring wells. In addition, hot water after gas separation in the process of flash power generation can be used secondary to generate power (bottoming cycle power generation).