We have been developing renewable energy sources by leveraging our long-accumulated expertise and knowledge in underground resources.. To date, we have been promoting the creation of renewable energy sources, mainly geothermal and hydroelectric power generation, in order to provide a stable supply of energy with minimal environmental impact, utilizing the expertise we have accumulated.

We generate stable and clean electric power through the power plants we maintain, including the Onuma Geothermal Plant and Sumikawa Geothermal Power Station (steam supply only, power generated by Tohoku Sustainable & Renewable Energy Co. Inc.), both in the Hachimantai area of Kazuno, Akita prefecture, and the Wasabizawa Geothermal Power Plant in the Takamatsu and Akinomiya areas of Yuzawa, Akita Prefecture and the Appi Geothermal Power Plant in Hachimantai, Iwate　Prefecture (both joint ventures by Mitsubishi Materials Corporation, Electric Power Development Co., Ltd., and Mitsubishi Gas Chemical Company, Inc.). In the fiscal year ended March 2025, we generated a total of 792 GWh of power (including 451 GWh from plants in which we have equity stake, etc.). The operation of our geothermal plants and steam supply systems effectively reduced CO2 emissions by approx. 142,000 tons (calculated based on emissions from Sumikawa Geothermal Power Station of Tohoku Sustainable & Renewable Energy Co. Inc., our equity stake in Wasabizawa Geothermal Power Plant of Yuzawa Geothermal Power Corporation, and our equity stake in Appi Geothermal Power Plant of Appi Geothermal Power Corporation).
In geothermal power generation, it is important to understand the unseen underground conditions to ensure a continuous and stable supply of steam. At the Sumikawa geothermal power plant, we will continue to monitor the underground conditions through detailed verification of data since the start of operation and reanalysis of the geological structure in order to improve the amount of electricity generated and continue stable operations at the site.

In August 2021, we launched a survey to quantify the geothermal resources in the Komonomori area (Kazuno), which is located northeast of the Onuma Geothermal Power Station, using subsidies from the Japan Organization for Metals and Energy Security (JOGMEC). Further, we have begun a survey to quantify the geothermal resources in the upstream area of the Appi River (Hachimantai), which is east of the Appi Geothermal Power Plant, in June 2022 using subsidies from JOGMEC. 
We are also continuing to conduct joint surveys with other companies in the Azuma-Adatara area of Fukushima prefecture.

Appi Geothermal Energy Corporation, which is a joint venture company formed by Mitsubishi Materials Corporation, Mitsubishi Gas Chemical Company Inc., and Electric Power Development Co., Ltd., started commercial operation of the Appi Geothermal Power Plant today.
The Appi Geothermal Power Plant is located at an altitude of approximately 1,130 meters and operates at an output capacity of 14,900 kW utilizing promising geothermal resources in the Hachimantai region of Iwate Prefecture. This was the first time in 28 years that a geothermal power plant with an output of over 10,000 kW has operated in Iwate Prefecture. All the electricity generated will be supplied to society under the Feed-In Tariff (FIT) system for renewable energy.

This project is supported by JOGMEC, applying a debt guarantee project for geothermal resource development funding.
We will contribute to the expansion of the use of renewable energy through the stable operation of the Appi Geothermal Power Plant.

We began preparations in the fiscal year ended March 2023 and conducted well drilling in the fiscal year ended March 2025. Through various investigations, we obtained information on the geology, rock characteristics, and temperatures of the sites, and in one of the wells, we were able to confirm formation temperatures that exceeded 300°C.
We have been communicating with local stakeholders (including the city of Kazuno and hot spring operators), and our continuous hot spring monitoring system is operating as planned.

We are utilizing the abundant experience and high technological capabilities we have cultivated over many years through our development and management of coal and metal mines for geothermal power generation. Regarding geothermal power generation, since commencing operations at the Onuma Geothermal Power Plant (Akita Prefecture) in 1974, we have played a central role in the construction and operation of the Sumikawa Geothermal Power Plant (Akita Prefecture, commenced operations in 1995), the Wasabizawa Geothermal Power Plant (Akita Prefecture, commenced operations in 2019), and the Appi Geothermal Power Plant (Iwate Prefecture, commenced operations in 2024).
We have been working on the "development and promotion of the use of renewable energies such as geothermal energy" and intend to engage in this project by making use of our experience and technological capabilities through investment to contribute to the success of the project.

In 2000, Mitsubishi Materials Techno Corporation entered the business of ground-source heat, which is heat from a renewable energy source, as a provider of total engineering solutions. The company has been providing services in the process from project proposal through investigation, design, and construction. 
The company has continued its R&D efforts and acquired patented technologies through projects commissioned by the government and others, aiming to become the No.1 company in geothermal technologies. As a result, the company has succeeded in building infrastructure using ground-source heat by developing commercial systems with various heat exchange methods, including not only the common borehole method but also its patented foundation pile method as well as horizontal and earth retaining wall methods. At present, Mitsubishi Materials Techno Corporation is promoting sales of these technologies as systems for using ground-source heat utilized through urban infrastructure, aiming to contribute to urban development in the future. 
Approx. 140 systems from the company have been installed. Since 2020, the large-scale utilization of ground-source heat has been increasing. For example, the company completed one of the largest projects in Japan, which combines the borehole method (100 m in depth x 120 boreholes) and the horizontal method (nine units x approx. 100 m long trenches), at a city hospital in Hachimantai. It also completed one of the largest projects in the Tokyo metropolitan area, which applied the foundation pile method (66 cast-in-place piles) at the Yokohama City Hall. In May 2022, Mitsubishi Materials Techno Corporation, the Yokohama City Government, Takenaka Corporation, and other companies received the 60th Gakkai-sho Gijutsu-sho (academic society award and technology award) in the building equipment category from the Society of Heating, Air-Conditioning and Sanitary Engineers of Japan for the implementation of the Yokohama City Hall environmental and facility plans. In addition, the ground source heat pump system using urban infrastructure also won the New Energy Award 2024 (Minister of Economy, Trade and Industry Award) in January 2025. 
The company will continue to help establish a decarbonized society by expanding the use of ground-source heat as renewable energy.