Producing Renewable Energy

Harnessing renewable energy sources such as geothermal and hydroelectric energy, both of which are 100% domestically produced resources, enables us to reduce consumption of the Earth's limited underground resources.
Alternative energy is also preferable to oil-fired thermal power in terms of CO2 emissions and is one of our priority measures to help combat global warming.

Reduction in CO2 emissions using renewable energyReduction in CO<sub>2</sub> emissions using renewable energy* The above figures have been recalculated based on the latest data published by the Central Research Institute of the Electric Power Industry (2010).

Geothermal Power Generation business

We stably generate environmental loading-reducing electric power through our Ohnuma Geothermal Plant and Sumikawa Geothermal Plant (steam supply only, power generated by Tohoku Electric Power Co., Inc.), both in the Hachimantai area of Kazuno, Akita prefecture. In fiscal 2018, we generated a total of 325 GWh of power, which is equivalent to a 240,000-ton reduction in CO2 emissions compared to oil-fired power.
In conducting the geothermal power generation business, we have to confirm the geothermal systems of Sumikawa area, in order to maintain continual and stable supplies of steam. We are working to maintain a geothermal reservoir at the Sumikawa Geothermal Area, with the aim of increasing the amount of power generated in the future. We have been examining data, and reanalyzing geothermal systems since we started operations at the site, as we continue to focus on maintaining stable operations.

Sumikawa Geothermal PlantSumikawa Geothermal Plant

Ohnuma Geothermal PlantOhnuma Geothermal Plant

Developing New Geothermal Power Generation

Conceptual drawing of the completed Wasabizawa Geothermal Power PlantConceptual drawing of the completed Wasabizawa Geothermal Power Plant

In addition to operating existing power plants, we are currently carrying out new projects too. Yuzawa Geothermal Power Corporation, established jointly with Electric Power Development Co., Ltd. and Mitsubishi Gas Chemical Co., Ltd., started construction of Wasabizawa Geothermal Power Plant in May 2015. In October 2015, we established Appi Geothermal Energy Corporation in conjunction with Mitsubishi Gas Chemical Co., Ltd., and conducted an environmental impact assessment for the construction of a geothermal power plant in the Appi area of Hachimantai city, Iwate prefecture. We are also in the process of conducting joint studies with other companies in Musadake in Hokkaido, and Bandai-Azuma-Adatara area in Fukushima prefecture.

New geothermal projectsNew geothermal projects

Environmental Impact Assessment by Appi Geothermal Energy Corporation

photoAn explanatory meeting for local residents on the preliminary documents of the environmental impact assessment at Hachimantai

We have been carrying out commercial studies in the western area of Appi Kogen in Hachimantai (Iwate prefecture) since fiscal 2005, conducting assessments in areas such as geothermal resources and economic viability. Having carried out studies in conjunction with Mitsubishi Gas Chemical Company Inc. on 28th October, 2015, we joined forces to establish Appi Geothermal Energy Corporation.
We are now planning to commence operations at a geothermal plant with a capacity of 14,900 kilowatts in 2023, operated by Appi Geothermal Energy Corporation. We began proceedings for an environmental impact assessment in October 2015. Having studied, forecast and evaluated the impact that establishing the Appi Geothermal Plant (tentative name) would have on the surrounding environment, on 25th April, 2017 we submitted a draft environmental impact statement for our environmental impact assessment to the Minister of Economy, Trade and Industry, and also sent copies to the governor of Iwate Prefecture and mayor of Hachimantai.


Hydroelectric Power Generation Business

We have a long history of generating hydroelectric power, dating back to 1898, when we built seven hydroelectric power plants in Akita prefecture, for the purpose of supplying enough power to run Osarizawa Mine (opened as a gold mine, later operated as a copper mine, closed in 1978) and homes in the local area. We were compensated for one of those power plants when a dam was built and the plant was submerged in 2000. The remaining six however are still operating today, selling on all of the power that they generate to a power company. Since 2014, we have successfully completed upgrades at three hydroelectric power plants, in an effort to deal with aging facilities. We successfully completed equipment updates at three hydroelectric power plants that were part of aging countermeasures started in 2014. We also completed updates at Oyu Hydroelectric Power Plant (Kazuno) in March 2018. We are determined to keep on securing both stable operations and stable revenue in the future.
In fiscal 2018, the combined power generated by all six hydroelectric plants was 93 GWh, which is equivalent to a 67,000-ton reduction in CO2 emissions compared to oil-fired power. We are currently planning a new hydroelectric plant on the Komatagawa water system, in an effort to generate even more renewable energy.

Oyu Hydroelectric Power PlantOyu Hydroelectric Power Plant


Solar Power Business

Having entered the solar power business in 2013, making effective use of idle group land, by 2017 we had built power plants in five locations as part of a joint venture with Mitsubishi UFJ Lease & Finance Company Limited. We are currently operating plants in Makabe (Ibaraki prefecture), Fukui, Torigoe (Fukuoka prefecture), Irigama (Miyagi prefecture), and Yabuki (Fukushima prefecture). In fiscal 2018, the combined total of power generated by all five solar power plants was 29 GWh, which is equivalent to a 21,000-ton reduction in CO2 emissions compared to oil-fired power.

Yabuki Solar Power PlantYabuki Solar Power Plant


Ground Source Heat Pump Systems (GSHP)

Helping to Save Energy and Reduce CO2 through Optimized Infrastructure and Rooftop Snow-Melting Systems

Mitsubishi Materials Techno Corporation is actively working on research and development of systems capable of harnessing "ground-source heat" as a form of renewable energy. It has successfully developed commercial systems using the borehole, foundation pile and horizontal methods, with over 100 systems installed nationwide since 2003.
We are working to develop systems to harness ground source heat using urban infrastructure. Having been included in a project spearheaded by the New Energy and Industrial Technology Development Organization (NEDO), aimed at developing technology to harness heat from renewable energies, in February 2016, Mitsubishi Materials Techno is now conducting research into low-cost GSHP systems that combine the SMW* system, which is commonly used in urban construction, with ground source heat. The end results will be compiled by the end of fiscal 2019.
From December 2015 to March 2018, the Company was commissioned by the Ministry of the Environment and conducted assessments based on empirical field trials and monitoring as to what impact the use of ground source heat has on underground ecosystems (especially microorganisms). Our report from the empirical trials concluded that we could not observe any impact on underground ecosystems by the use of ground source heat. This result is reflected in the Ministry of the Environment's Guidelines for the Use of Ground Source Heat (Revised and Enlarged Edition) (March 2018).

  • * SMW system: Method of construction that involves taking soil (S) and mixing (M) it together with cement slurry onsite, to form a connected wall (W) in the ground.

Overview of the geothermal heat pump (GeoHP) systemOverview of the geothermal heat pump (GeoHP) system

Examples of systems in use

  Facility Location Started operations
Bore hole systems Kazuno Wide-Area Administrative Union Fire Department (air conditioning) Kazuno, Akita prefecture 2015
Tokyo Metro Co., Ltd. Nakano Depot (air conditioning) Tokyo (Nakano ward) 2015
Ishinomaki Port Government Building (air conditioning) Ishinomaki, Miyagi prefecture 2014
Tokyo Skytree (district heating system) Tokyo (Sumida ward) 2012
Foundation pile systems Akita City Hall (air conditioning, snow-melting system) Akita, Akita prefecture 2016
Hachimantai City Hall (air conditioning) Hachimantai, Iwate prefecture 2014
Horizontal systems Iyo City Office (air conditioning) Iyo, Ehime prefecture 2017
Setagaya-Daita Station and Higashi-Kitazawa Station (Odakyu Line) (air conditioning) Tokyo (Setagaya ward) 2014
Open loop systems Mitsubishi Materials Techno Corporation Kazuno office (air conditioning) Kazuno, Akita prefecture 2015

Our Fifth Stakeholders' Meeting

Our Fifth Stakeholders' Meeting was held and we discusssed on the theme “Thinking about the future of renewable energy -The role to be played by the Mitsubishi Materials Group in its main business- .”