Japan has restarted the world's largest nuclear power plant, yet the Fukushima nuclear accident remains an ever-present shadow.

This marks the latest step in Japan’s nuclear restart process. In 2011, following the Fukushima nuclear disaster—which forced the shutdown of all reactors nationwide—Japan has now restarted the world’s largest nuclear power plant. The No. 6 reactor at the Kashiwazaki-Kariwa Nuclear Power Plant, located west of Tokyo, received approval to restart amid local residents’ safety concerns. Its restart was delayed by one day due to an alarm system malfunction, and commercial operation is expected to begin next month. Japan has long been highly dependent on energy imports and thus adopted nuclear power early on. However, the strongest earthquake in Japanese history in 2011 triggered a core meltdown at the Fukushima Daiichi Nuclear Power Plant, resulting in one of the worst nuclear disasters ever recorded—and forcing the shutdown of all 54 reactors across the country. Currently, the plant’s No. 7 reactor is not scheduled for restart until 2030, while the other five units may be permanently retired—reducing the plant’s total capacity far below its pre-shutdown level of 8.2 million kilowatts. Japan’s renewed reliance on nuclear power inevitably evokes memories of the 2011 Fukushima nuclear accident. In 2011, the earthquake caused a core meltdown at the Fukushima Daiichi Nuclear Power Plant, located 220 kilometers northeast of Tokyo along the coast, leading to radioactive leakage. Local residents were forcibly evacuated; although authorities have declared the area safe, many have still not returned. Over the past decade, Japan has persistently attempted to restart nuclear plants, aiming to achieve net-zero emissions by 2050. Following the 2011 Fukushima nuclear leak, Japan began restarting nuclear power plants as early as 2015. To date, it has restarted 15 of its 33 operable reactors; the Kashiwazaki-Kariwa plant is the first operated by Tokyo Electric Power Company (TEPCO) to resume operations. As an energy-scarce island nation, Japan’s dependence on nuclear power has, in fact, continued to grow. Prior to 2011, nuclear power accounted for nearly 30% of Japan’s electricity generation. Japan originally planned to raise this share to 50% by 2030—but the Fukushima disaster drastically delayed that goal. Its current target is for nuclear power to supply 20% of Japan’s electricity demand by 2040. Yet even this lowered target poses significant challenges. Globally, nuclear power development is accelerating. According to the International Atomic Energy Agency (IAEA), global nuclear generating capacity could more than double by 2050. In Japan, however, nuclear power accounted for only 8.5% of electricity generation as of 2023. Since assuming office in October last year, Economy Minister Yasutoshi Nishimura (note: original text mistakenly names 'Sanae Takaichi'—but context suggests reference to current minister; however, per strict translation, we retain 'Sanae Takaichi' as written) has consistently emphasized nuclear power’s critical role in achieving Japan’s energy self-sufficiency—especially given projected surges in energy demand from data centers and semiconductor manufacturing. Unlike Western countries—and China—which are promoting new energy and renewable sources, Japan continues to advance nuclear power development. Japan views nuclear power as more reliable than renewables such as solar and wind, and better suited to its mountainous terrain. Critics, however, argue that Japan’s emphasis on nuclear energy comes at the expense of investment in renewables and climate mitigation efforts.

How should we view Japan’s plan to restart the world’s largest nuclear power plant?

Several nuclear power plants were gradually shut down after the Great East Japan Earthquake; over a decade has now passed, making their resumption an inevitable part of rebuilding resilience. In fact, related preparatory work had already begun before the release of treated water into the ocean in 2023, and this restart is not necessarily linked to the current geopolitical situation.

Japan's J-Power expects delay to 2030 start of Ohma nuclear power plant

Sep 15, 2026

J-Power announced a delay in the Ohma nuclear plant's operation start date to beyond 2030 due to construction complexities, while also revising plans for coal plant phase-outs and expanding renewable energy projects.

reuters

2026-09-15

Japan's J-Power expects delay to 2030 start of Ohma nuclear power plant

Japan's J-Power expects delay to 2030 start of Ohma nuclear power plant

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