Japan - Country Commercial Guide
Civil Nuclear Power
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Civil Nuclear Power Market Size (in terms of electricity generated)

Japanese Fiscal Year2009
Total Electricity Generated (TWh)925.4     1,021.6     1,000.8        863.5        832.7
Growth Ratio against Previous Year -2.7%-2.0%-13.7%-3.6%
Nuclear279.7           63.8           38.8          67.8          53.5
Coal568.4         326.6         310.2        282.6        280.7
LNG         381.5         389.9        319.1        301.9
Oil and Other Thermal Generation           64.1           63.6          53.5          53.0
Hydro74.5           79.6           78.4          85.8          83.2
Solar0           69.4           79.1          19.0          21.8
Wind0             7.6             9.0             7.4             7.4
Geothermal2.7             2.8             3.0             2.0             1.9
Biomassn/a           26.1           19.1          26.2          25.1
Nuclear Share30.2%6.2%3.9%7.9%6.4%

Unit: Terawatt-hour (TWh)

Source: Ministry of Economy, Trade, and Industry (METI), government of Japan (GOJ)

Civil nuclear power has reemerged as Japan’s most viable clean energy option as the current global energy crisis continues. Following the 2011 Fukushima Daiichi nuclear accident, the GOJ suspended the operations of most of the country’s nuclear power reactors. However, with a national mandate to achieve carbon neutrality by 2050, Japan is again ready to embrace nuclear power as a strategic energy source. Also, the energy crisis triggered by the pandemic and Russia’s invasion of Ukraine have once again made the country aware that it cannot rely heavily on any single fuel source. Due to the nation’s scarce indigenous energy resources, the GOJ has quickly shifted to reposition nuclear power as a favored energy source, second only to renewable energy.

In August 2022, Prime Minister Fumio Kishida made a surprising speech where he announced Japan’s nuclear comeback via the restart of the country’s nuclear reactors, the construction of new plants, and increased research and development of new reactor technologies, including small modular reactors (SMR). His policy initiatives developed into Japan’s Law on Power Sources for Green Transformation and Decarbonization in May 2023, which changed to energy laws to promote the introduction of renewable energies and make maximum use of nuclear power, while it stresses that, under any circumstances, ensuring the safety of all aspects of operation, maintenance, and administration of nuclear power plants is a prerequisite; they must pass the safety examination by the Nuclear Regulation Authority (NRA); and local communities must agree to restarts of the reactors.

Specifically, the new law made four key revisions: 1) Clarification of principles regarding nuclear power generation; 2) Increasing restrictions on older nuclear reactors; 3) Streamlining restrictions on operational periods for nuclear power generation; and 4) “Smooth and steady promotion of decommissioning”, whereby the Nuclear Reprocessing Organization of Japan (NuRO) will take a major responsibility for the coordination of decommissioned reactors nationwide, and Japanese nuclear power operators will be required to make payments for decommissioning contributions to NuRO. Most notably, nuclear plants may operate for longer than 60 years if approved by the economics (METI) minister and all extensions are subject to regular inspections by the NRA, which is tasked with inspecting the functioning status of the plants 30 years after the start of operations and every 10 years thereafter. It is widely believed that the new law has paved the way for a comprehensive overhaul of Japan’s nuclear policy.

As civil nuclear power has once again become one of Japan’s desirable energy options, ten Japanese electric power companies (EPCs), major nuclear vendors, and local Japanese nuclear energy suppliers will seek the latest U.S. civil nuclear technologies to restart Japan’s nuclear power plants safely, effectively, and economically.

Japan is also the world’s second-largest nuclear decommissioning and decontamination (D&D) market, outranked only by the United States. D&D projects are taking place in at least one Japanese power plant owned by eight EPCs, with each project expected to last for 20–30 years. In addition, U.S. firms are supplying several products and technologies for Japan’s most notable and unique D&D project at the Fukushima Daiichi Nuclear Power Station.

The GOJ is also looking into developing next-generation reactor technologies such as the Innovative Light Water Reactor (ILWR), SMR, Fast Neutron Reactor, High Temperature Gas-Cooled Reactor (HTGR), and Fusion Reactor. Several phases of feasibility studies of such reactors have been launched, and the GOJ has publicly shared aspirations of beginning use of these technologies between 2030 and 2050. The U.S. Commercial Service Japan (CS Japan) understands that the GOJ is considering all U.S. technologies as part of its plans to bring more reactors online. Slowly but steadily, we anticipate Japan’s research and development of new reactor technologies to continue gaining momentum, thus raising opportunities for the U.S. nuclear reactor and subcomponent industries.

Leading Sub-Sectors 

The following are the three leading sub-sectors in Japan’s civil nuclear power industry: (1) the restart of existing nuclear plants; (2) the D&D of Fukushima Daiichi Nuclear Power Station and other non-accident commercial reactors; and (3) next-generation reactor technologies, including SMRs.

Nuclear Restarts 

Ten EPCs own all 33 operable commercial nuclear reactors in Japan. At present, the EPCs have submitted the necessary applications to the NRA, requesting to restart 25 of these reactors. Of the 25 reactors, as of August 7, 2023, 11 had resumed operations since 2011, the latest being Takahama Unit 1, which is the oldest nuclear reactor in Japan and is owned by The Kansai Electric Power Co., Inc. Of the remaining 14 reactors, the NRA has approved six and is reviewing eight. CS Japan engages with all the EPCs to obtain updates on their general procurement policies and specific products or technologies that they are looking for (refer to the Opportunities section). In addition to “nuclear restart” issues, these include various aspects of nuclear operations managed by the EPCs.

Nuclear Decommissioning and Decontamination (D&D)

  1. Fukushima Daiichi Nuclear Power Station

Tokyo Electric Power Company Holdings (TEPCO) oversees the decommissioning of the four damaged Fukushima Daiichi reactors. The project consists of treating radioactive water, removing nuclear fuel debris, and spent nuclear fuels, managing radiological waste, and ultimately demolishing the facilities.

Removing fuels and fuel debris in Units 1, 2, and 3 is still an uncharted area for the domestic and international nuclear communities. To reduce the risk of any accident, preparations for this most challenging part of the project are under way. The aim is to conduct the inner investigation of the Unit 2 reactor, begin the trial retrieval while removing obstacles within the pressure container vessel, and gradually enlarge the scale of the retrieval. The International Research Institute for Nuclear Decommissioning, GOJ, and Mitsubishi Heavy Industries (MHI) jointly developed the robotic arms specifically for these efforts.

In this ongoing 40-year project, to date, U.S. firms have contributed products and technologies critical to water treatment efforts and have offered U.S. waste management methodologies, both with a certain degree of success. CS Japan is in close contact with TEPCO and can assist with efforts concerning any U.S. solutions to mitigate the problems of the Fukushima D&D.

  1. D&D of Non-Accident Commercial Reactors 

As of August 2023, fourteen non-accident shutdown reactors are being decommissioned at an average estimated cost of $500–$700 million each. Generally, domestic reactor vendors Toshiba, MHI, and Hitachi, as well as major engineering firms or general contractors, serve as the prime contractors to EPCs. However, U.S. firms gained foothold by partnering with Japanese firms and participating in bigger D&D projects in western Japan using Pressurized Water Reactors. Although Japan has traditionally been slow to adopt U.S. project management expertise that could minimize costs and shorten project schedules while adhering to relevant safety measures, U.S. products and technologies are both highly regarded and in high demand. CS Japan is in close contact with all nuclear EPCs and is ready to assist with the promotion of U.S. products and technologies that could contribute to the D&D of non-accident shutdown reactors.

Next-Generation Advanced Reactor Technologies, including SMR

In February 2023, the Japanese Cabinet approved the Basic Policy Towards Realizing the Green Transformation, where it stated that the development of next-generation advanced reactors equipped with new safety mechanisms would be promoted so that they would be constructed within the sites of power stations that are to be decommissioned, thereby replacing the old units. Also, the Atomic Energy Basic Act, which was revised in 2023, states that contributing to a stable supply of electric power by actively using nuclear power generation and to the realization of a decarbonized society is “the country’s responsibility” for the first time in history.

With this policy statement and initiative, the GOJ aims to initiate demonstration and commercial operations of next-generation advanced reactors between 2030 and 2040. ILWR, which is technically the most mature reactor where existing light-water technologies can be utilized, is the most favored reactor in Japan; commercial operation is targeted for the late 2030s. HTGR comes next, the demonstration operation of which is targeted for the late 2030s, followed by the Fast Neutron Reactor and SMR (both demonstration operations) in the early 2040s, and the Fusion Reactor (operation target period unspecified).

All U.S. advanced reactor technologies are well positioned to capture a good share of the Japanese market for next-generation nuclear power in the future. After successful advocacy and engagement with the GOJ and major Japanese nuclear companies, U.S. nuclear companies were all awarded Japan’s national feasibility study proposals for an advanced nuclear power plant, including SMR. Japan also aims to support local suppliers’ participation in U.S. and European SMR projects. To showcase Japan’s commitment, the Japan Bank for International Cooperation purchased an equity in a U.S. SMR manufacturer. In January 2023, METI and the U.S. Department of Energy agreed to cultivate opportunities for cooperation on nuclear energy, such as the development and construction of next-generation advanced reactors, including SMRs, within each country and in third countries.



  • The 38th New Orleans Association (NOA) Conference (Tokyo, May 2024): CS Japan conducts an annual one-on-one matchmaking business event called the “NOA Conference,” where international procurement managers from all of Japan’s regional EPCs (Hokkaido, Tohoku, Hokuriku, Chubu, Tokyo, Kansai, Shikoku, Chugoku, Kyushu, Okinawa EPCs, J-Power, and Japan Atomic Power Company) gather to meet with U.S. suppliers. The next NOA Conference is scheduled to take place in May 2024. The program will be uploaded in January 2024. Please refer to the last Conference details on the website: Japan Trade Events
  • The 8th International Forum on the Decommissioning of the Fukushima Daiichi Nuclear Power Station (August 2024 in Fukushima Prefecture) is organized by Nuclear Damage Compensation and Decommissioning Facilitation Corporation.
  • Tsuruga International Symposium 2024 (November 2024 in Fukui Prefecture) is organized by the Ministry of Education, Culture, Sports, Science, and Technology, GOJ. The event focuses on research & development reactors belonging to Japan Atomic Energy Agency.

Commercial Service, Japan Contact

For additional information about Japan’s civil nuclear power business sector, please contact Commercial Service Japan (CS Japan) at Office.Tokyo@trade.gov or Mr. Takahiko Suzuki at Takahiko.Suzuki@trade.gov.