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Released December 05, 2025 | GALWAY, IRELAND
Written by Martin Lynch, European News Editor for Industrial Info (Galway, Ireland)
Summary
Japan could soon restart the world's largest nuclear plant following its closure in 2011 after the partial meltdown of its sister plant, Fukushima Daiichi. A landmark decision by a regional assembly is currently being debated and if the outcome is positive, two units at Kashiwazaki-Kariwa could be online as soon as January 2026.
Landmark Moment for Japanese Nuclear
The world's largest nuclear power plant could be restarted in Japan as soon as next month, 14 years after it was forced to close by government decree.
The owner and operator, Tokyo Electric Power Company (TEPCO) (Tokyo), has been pushing for the controversial restart of the Kashiwazaki-Kariwa nuclear power plant in the Niigata Prefecture. The plant, along with all other nuclear power plants, were forced to close by the Japanese government in 2011 after the Fukushima accident. A successful restart could speed up Japan's return to nuclear power as the country currently needs to import roughly 90% of its energy requirements.
In 2011, the Fukushima Daiichi nuclear plant suffered a partial meltdown in the wake of the country's worst recorded earthquake and subsequent tsunami. That plant is also owned by TEPCO, which is still paying compensation for the Fukushima disaster while also decommissioning the plant. Niigata's governor has agreed to restart units 6 and 7, and TEPCO has spent years improving safety procedures and trying to change anti-nuclear opinions locally and nationally. The company has also had to apologise for a number of serious security issues at the plant, including failing intruder detection systems, unauthorized access to sensitive areas and the mishandling of sensitive documents. At a recent visit to the plant by the press and the Japan Business Federation, TEPCO President Tomiaki Kobayakawa argued: "The use of nuclear energy is essential in Japan, which has few resources."
Impact of the Fukushima Disaster
Prior to the Fukushima disaster in 2011, nuclear energy accounted for about 30% of Japan's electricity mix, supplied by 54 reactors. After the accident, most were shut down over the following year, forcing the country to rely on fossil-fuel power for most of its electricity. Since then, 14 reactors have been slowly brought back online, and in 2023 nuclear power supplied 8.5% of the country's power. In order for the country to reach its 2030 target of 20% nuclear power in the power mix, most of the 36 reactors still capable of operation will have to be brought back online.
The Return of Nuclear Power in Japan
Recent Japanese governments have supported a return of nuclear power. In June, the government approved a law that will allow nuclear reactors to operate beyond 60 years - reversing a 60-year limit imposed on plants in 2011 after Fukushima. It has argued in recent years that nuclear power will be essential for the country to reduce its almost complete reliance on fossil-fuel imports and to help transition to more renewable energy. Industrial Info reported in October that the country's new Prime Minister Sanae Takaichi is in favor of restarting idled nuclear power plants. However, in post-2011 Japan, the nuclear industry is hampered by negative public opinion and stricter regulations and permitting aimed at preventing another tsunami meltdown. For additional information, see October 22, 2025, article - Japan's New Prime Minister Pushes Nuclear and Energy Security.
Nuclear Projects in Japan
Industrial Info is tracking 78 nuclear power related projects in Japan worth US$35 billion, only one of which is a new-build. The majority of current spending is related to replacement reactors, plant closures and refurbishment. Subscribers to Industrial Info's Global Market Intelligence (GMI) Project Database can click here for the reports.
Key Takeaways
- Japan edges closer to voting in favor of restarting the world's largest nuclear plant in January.
- The plant, along with all other nuclear plants in Japan, were shut after the 2011 partial meltdown at the Fukushima Daiichi nuclear plant.
- Japan relies on energy imports for roughly 90% of its power.
About Industrial Info Resources
Industrial Info Resources (IIR) is the leading provider of industrial market intelligence. Since 1983, IIR has provided comprehensive research, news and analysis on the industrial process, manufacturing and energy related industries. IIR's Global Market Intelligence (GMI) helps companies identify and pursue trends across multiple markets with access to real, qualified and validated plant and project opportunities. Across the world, IIR is tracking over 200,000 current and future projects worth $17.8 Trillion (USD).
