Resource Guide to Geothermal: A Domestic Alternative to Nuclear Energy in Japan


Matsukawa Geothermal Power Plant

The newly released Energy Strategy in Japan pursues a comprehensive, diverse energy mix. Reports say that the Diet requested that, as a condition of including nuclear into the mix, the energy strategy emphasize increasing research and growth into renewable energies. Among the possible sources of energy, geothermal energy has large potential.

Geothermal energy is energy generated by the heat trapped in the Earth’s core, from the formation of the planet and from the radioactive decay of naturally occurring minerals. Geothermal power derived from that energy is cost-effective, reliable, sustainable, and environmentally friendly,but has historically been limited to areas near tectonic plate boundaries. Forum on Energy has compiled the information and resources below regarding the possibilities of geothermal energy as a strong competitor to nuclear energy.

Geothermal Market

Japan, located on the “Ring of Fire,” is one of the most tectonically active countries in the world, with around 120 active volcanoes. It has been ranked as the world’s third-richest nation in geothermal power development potential, behind the United States and Indonesia, and its geothermal resources are estimated to be able to generate as much as 23 million kilowatts of energy.

Currently there are 18 geothermal plants in operation, located mostly in North Honshu and in Kyushu. The plants that are in operation provide a modest 520 megawatts, according to the Geothermal Energy Association. Japan’s geothermal plants and their energy capacity are listed below:


Onuma Geothermal Power Plant 9.5 Akita
Sumikawa Geothermal Power Plant 50 Akita
Uenotai Geothermal Power Plant 28.8 Akita
Yanaizu-Nishiyama Geothermal Power Plant 65 Fukushima
Mori Geothermal Power Plant 50 Hokkaido
Kakkonda Geothermal Power Plant  80 Iwate
Matsukawa Geothermal Power Plant  23.5 Iwate
Ohdake Geothermal Power Plant  12.5 Kagoshima
Yamagawa Geothermal Power Plant  30 Kagoshima
Ohgiri Geothermal Power Plant  30 Kumamoto
Suginoi Geothermal Power Plant  3 Kumamoto
Onikobe Geothermal Power Plant  12.5 Miyagi
Takigami Geothermal Power Plant  25 Miyazaki
Hatchobaru Geothermal Power Plant 110 Oita
Kirishima Kokusai Hotel Geothermal Power Plant 0.1 Oita
Kuju Geothermal Power Plant  2 Oita
Takenoyu Geothermal Power Plant  0.05 Oita
Hachijojima Geothermal Power Plant  3.3 Tokyo


Despite its rich renewable resource, Japan’s development of geothermal power has fallen short of its potential.

Geothermal development first started in Japan in 1925 with an experimental unit in Beppu, Oita Prefecture in Southern Japan. Research continued after WWII, and the first commercial plant was established in Matsukawa in 1966. Geothermal energy production grew gradually because the technology was, at the time, little known. Between the 1970s and 1980s, high efficiency 50MW watt plants were constructed, building off of the research of the previous generation. The interest in geothermal intensified because of the world-wide oil crisis of the time. Over the last 30 years, it has become economical to build small 20-30 MW geothermal plants because of advances in exploration and drilling. But, there have not been any geothermal plants constructed in 15 years until 2014

Since 2011, Japan has renewed its interest in alternatives to nuclear energy and fossil fuels. This has led to recent a flurry of activity in the geothermal market.


Japan’s Current Geothermal Situation

In 2003 the national government pledged support for renewable energies but little change occurred until 2012, when the government allowed for exploration in the nation’s national parks, and extended membership of its renewable portfolio to a wider variety of geothermal plants. In July 2013, it also introduced a feed-in tariff system to encourage investment in the geothermal sector. The feed-in tariff will force the ten regional electricity monopolies to buy renewable energy at above-market rates—though a price has not yet been set, according to The Economist.

As a result, a further 20 sites across the country are presently being assessed for the suitability for projects.

Recently, two projects have received loan guarantees to start projects.

But, there is local community-level resistance to plant construction, based on fears that the plants will deplete resources for hot springs and pollute the parks. As a result, there is now a movement to launch small-scale geothermal power plants as a key element to the country’s expansion plans, creating a new energy source while revitalizing local communities at the same time.

More than 60 spots around the country are currently being tapped by businesses and officials as possible sites for plants, according to Dutch news outlet Deutsche Welle.


Finding the Right Kind of Geothermal Energy


Source: IGA

Geothermal energy has many uses, from heating systems, industrial applications to electricity. As you can see from the embedded chart from the International Geothermal Association and adapted from Lindal, 1973, geothermal energy for power generation requires high temperatures that are not useful for other applications. This type of geothermal energy is rarely found in nature. The organization also notes: “The Lindal diagram emphasises two important aspects of the utilization of geothermal resources (Gudmundsson, 1988): (a) with cascading and combined uses it is possible to enhance the feasibility of geothermal projects and (b) the resource temperature may limit the possible uses. Existing designs for thermal processes can, however, be modified for geothermal fluid utilization in certain cases, thus widening its field of application.”

Around the world, high temperature hot spring water (about 80-120℃) can be utilized for power generation by applying the Kalina cycle system. The Kalina is a binary system which uses geothermal steam to heat a second liquid with a lower boiling point, in this case water mixed with ammonia. The pressure from this second liquid is used to turn the turbine, according to the Geothermal Handbook produced by the Energy Sector Management Assistance Program.

Japan has about 28,000 hot springs that are naturally discharging or artificially drilled. An estimation suggests that using 1,500 hotter wells and springs among them, as much as 723 MWe could be generated without additional drillings.

Most high-temperature fluid resources are located in the Northeast’s Tohoku and Southwest’s Kyushu, home to the Kuju volcano. Japan sits above a subduction zone, so the archipelago possesses many geothermal fields with low-enthalpy. These regions have potential for development with organic rankine cycle (ORC) systems and fluid temperatures of 100 C, or 212 F, according to Renewable Energy World.


Opportunity: Who Works on Geothermal in Japan?

According to the World Bank Energy Sector Management Assistance Program (ESMAP), it is useful to understand the Geothermal industry in terms of each phase of construction. The authors of the ESMAP Geothermal Handbook describe the different categories in the following table.

According to the Handbook, “the market environment for the manufacture and supply of power plant equipment for geothermal energy generation is very competitive for most types of equipment, except for turbines and generators (gensets), which currently are available from only a small number of large suppliers.” Japanese companies currently lead the geothermal genset market. Japan’s three market leaders (Mitsubishi, Toshiba, and Fuji) have produced at least 80 percent of all gensets sold to date. These turbines are mostly exported, since Japan produces only about 540MW of geothermal energy. “Ormat from Israel/USA and UTC/Turboden from USA/Italy are the market leaders for binary power plants, which are preferred for low and medium temperature resources,” reports the Handbook.

Given the experience of Japanese government, scientists and private sector companies, it can be expected that any expansion in Japan’s domestic geothermal industry will be dominated by Japanese entities.

There have been a few new projects so far.

A partnership between Toshiba and Orix, who set up a joint geothermal power generation company to build a plant in Gifu, is scheduled to go online in early 2015. “The two companies see the plant in Gifu Prefecture, central Japan, as a test site for further facilities in Hokkaido, Tohoku — the region devastated by the March 2011 earthquake and tsunami — and on Japan’s southernmost main island of Kyushu,” according to Deutsche Welle

Utility Chuo Electric Power Co, and a subsidiary are also opening a plant in Kumamoto, Kyushu. A consortium of J-Power, Mitsubishi Materials Corp. and Mitsubishi Gas Chemical Co. last year announced the creation of joint venture Electric Power Development Co. to develop a geothermal power plant Akita Prefecture, reports Renewable Energy World.

Another 10-company consortium, headed by Idemitsu Kosan Co. and Inpex Corp., has similarly announced plans to develop Japan’s largest geothermal plant, in the Bandai-Asahi National Park in the Fukushima Prefecture. With an anticipated output capacity of 270,000 kilowatts, the developers are hoping to have the plant operational in the early years of the next decade.



Japan’s electricity is distributed through 10 utility companies that own their own power plants and grids, which are not always compatible across regions. Given the major costs to utilities associated with the shutdown of nuclear power plants, utilities have not moved on expanding geothermal energy. But, according to the revamped energy plan, which expands the importance of renewables energies in the energy mix, it is likely that will change in the future.

Have geothermal plants been built before?

There have been no geothermal plants built in Japan for 15 years, until March 2014. Some of the barriers to construction of new geothermal plants have included, “strong resistance from local communities who are protective of their hot spring industries and associated tourism, with many potential sites for plants located in government- protected areas,” according to the Telegraph. Hot spring (also called onsen) owners also argue that tapping heated aquifers in volcanic Japan for energy will drain the springs dry, increase pollution and “ruin a cherished form of relaxation,” reports The Economist.

Many also harbor misconceptions about whether using geothermal for energy will cause the pressure of hot springs to depreciate. Hot-spring owners worry about depression or running out of their resources, increasing resistance against geothermal energy plants to prevent these problems.

While there is evidence that overuse of a geothermal site can cause the pressure to drop, a search by this writer has not uncovered evidence that geothermal for electricity and hot springs are in direct competition. There is some indication that the geothermal water used for electricity can be reused for hot springs through a “cascade” sharing system.

Opinions about protecting natural resources changed after the public mood shifted away from nuclear energy in 2011. Both changes in government policy and to public mood have opened up opportunity for more projects. Many of the projects in the pipeline — including the new Kumamoto plant — are circumventing local opposition to geothermal plants by limiting the size of operations and working closely with the community. But they expect it will take ten years before they start generating electricity.

In Japan, development costs are also high, critics point out, with a 20 megawatt geothermal plant requiring an initial 7 million U.S. dollars to assess and then a further investment of between $20 million and $40 million to complete the drilling. The typical seven years from discovery to commercial operation of a geothermal plant is another concern for potential investors.


Regulatory and Legal Approaches to Geothermal

Most promising geothermal fields are located in natural parks and spas. There is strong local pressure to preserve the natural beauty of these areas.

Japan eased rules in March 2012 to allow geothermal developments in protected national parks as part of an effort to boost clean energy supplies.


Opportunities for Outside Companies

Nevada’s Ormat Technologies Inc. is a world leader in geothermal energy. In 2004, Nevada’s Ormat Technologies Inc. supplied the country with its most recent geothermal project, which is also its first ORC binary system at the Hacchobaru Power Station in Kyushu. The 2.2-MW unit enabled the existing power plant to generate additional electricity from water that exits steam turbines before re-injection underground. Recently Ormat signed an agreement with JFE Engineering to build and operate new power plants with support from Japan’s Itochu Power Corp. Many of these projects are overseas. But despite these successes, it is likely that the market for geothermal in Japan will be dominated by domestic companies.




  • Geothermal Opportunities in Japan: An April 2012 report written by a New Zealand company, Worldview, whose mission is to “lift New Zealand’s international engagement through rigorous analysis of global issues and their ‘NZ dimension.'”
  • Geothermal Energy in Japan: A report from the Geothermal Research Society of Japan focusing on history, resources and technology.
  • Geothermal Japan: A bulletin release from the Geothermal Resources Council, focusing first on Japan’s geothermal history and pivoting to its future potential.


  • Geothermal Handbook: The Geothermal Handbook, released by the Energy Sector Management Assistance Program, is a comprehensive guide to planning and financing geothermal projects. Based on lessons learned from multiple investment successes and failures, the handbook presents a step-by-step understanding of the phases of geothermal project development, looking at the risks involved and at the policies, institutions and financing mechanisms needed to successfully bring projects to fruition. The report stresses the importance of concerted international assistance to help finance geothermal scale-up in the early, risky phases of development, in order to mitigate risk and make projects attractive to private investment.