Tokyo Ohka Kogyo Introduces Off-site Corporate PPA Using Geothermal Power

Tokyo Ohka Kogyo Co., Ltd. (President and Representative Director, Shunichi Taniguchi, hereinafter "Tokyo Ohka Kogyo") and Kyuden Mirai Energy Co., Ltd. (President and Representative Director, Koji Mine, hereinafter "Kyuden Mirai Energy") are pleased to announce the introduction of an off-site corporate PPA*1 utilizing geothermal power at Tokyo Ohka Kogyo's factory in Kumamoto Prefecture (hereinafter "This Initiative"). This is the first initiative of its kind by a semiconductor materials manufacturer to introduce an off-site corporate PPA using geothermal power*2.

Geothermal Power Plant (Kyuden Mirai Energy Hacchobaru Power Plant)

Supply Destination Factory

As of fiscal year 2023, renewable energy (hereinafter "RE") accounts for 26.1% of the total electricity generated in Japan*3. Among RE sources, geothermal power can generate and supply stable electricity 24 hours a day, 365 days a year, regardless of weather or time. Its facility utilization rate*4 is 82%*5, which is the highest among RE sources, including hydropower, wind power, and biomass.

● Overview of the Introduction Scheme

Renewable energy generated at four geothermal power plants owned by Kyuden Mirai Energy (Hacchobaru Power Plant and Takigami Power Plant in Oita Prefecture, Yamakawa Power Plant and Okiri Power Plant in Kagoshima Prefecture) will be supplied through Kyushu Electric Power Co., Inc., an electricity retailer, to two sites operated by Tokyo Ohka Kogyo in Kumamoto Prefecture: the Aso Plant and the Aso Plant Aso Kumamoto Site. Through this initiative, approximately 50% of the electricity consumed annually at these two sites by Tokyo Ohka Kogyo will be geothermal-derived electricity, achieving an annual CO2 reduction effect of approximately 1,730 tons*6.

● Decarbonization Policies of Each Company

Tokyo Ohka Kogyo

Under its management vision "The e-Material Global CompanyTM: Responding to the Expectations of Society with Chemistry for a Rich Future," the Tokyo Ohka Kogyo Group is promoting decarbonization management with the aim of achieving carbon neutrality by 2050. This initiative is one of the concrete measures to achieve this goal, leading to the diversification of renewable energy procurement methods and the strengthening of a stable electricity procurement base, taking into account future regulations and international trends. We will continue to promote initiatives towards achieving carbon neutrality by 2050, while simultaneously ensuring a stable supply of energy necessary for business activities and reducing environmental impact.

Kyuden Mirai Energy

Kyuden Mirai Energy aims to become "a world-leading green energy company that pioneers the future." Leveraging its strength as the only RE operator in Japan that owns five major RE sources (solar, wind, biomass, geothermal, and hydro), we will contribute to the spread and expansion of RE by actively responding to the diversifying energy needs of customers and society.

*1 A contract method in which a power producer who owns RE power sources and a power purchaser enter into a purchase and sale agreement for RE electricity at a pre-agreed price and period, and RE electricity is supplied to customers located away from the power generation site via the transmission and distribution network.

*2 According to Kyuden Mirai Energy's research (as of July 2026)

*3 Source: "Share and Introduction Status of Domestic Natural Energy Electricity in FY2023 (Preliminary Report)" (NPO Environmental Energy Policy Institute)

*4 The percentage of electricity generated by power generation facilities compared to the amount of electricity that would have been generated if the facilities had been operated at their rated output continuously (Total electricity generated (kWh) / (Elapsed time x Facility output (kW)) x 100)

*5 Source: "RENEWABLE POWER GENERATION COSTS IN 2023" (International Renewable Energy Agency (IRENA))

*6 Calculated based on Kyushu Electric Power's (electricity retailer) CO2 emission factor (FY2024 actual results) "Basic and Adjusted Emission Factor: 0.000472 t-CO2/kWh (Other Customers)"