Japan could replace up to 14 reactors by the 2050s under new proposal

Japan will need to replace as many as 14 of its nuclear reactors by the 2050s in order to meet its future energy demands, a recently released draft policy proposal states.

The details: Officials from the Japanese Ministry of Economy, Trade, and Industry presented the draft proposal at a nuclear subcommittee hearing on June 5. The origins of the draft stem from the 7th Strategic Energy Plan, a policy the Japanese agency adopted in 2025 that gave direction on how to meet the country's expected energy needs and what sources to depend on. The plan has nuclear energy's share of the country's power generation mix growing from 8.5 percent in 2023 to approximately 20 percent in 2040.

To meet the plan's nuclear energy targets, Japan will need to replace between two and five of its aging reactor units by the 2040s. By the 2050s, Japan will need to have replaced between 11 and 14 reactors (this includes the reactors from the 2040s target). This roughly translates to 2.2 GW-5.5 GW of nuclear power capacity for the 2040s target, and 12.7 GW-16 GW for the 2050s target.

The proposal is one of the strongest pushes to reinvigorate nuclear power in Japan in recent years. The 2011 Tōhoku earthquake and tsunami and ensuing accident at Fukushima Daiichi prompted the shutdown of all of Japan's nuclear reactors, which numbered 54 at the time. Prior to 2026, only 14 of 33 operable reactors had restarted.

Japanese Prime Minister Sanae Takaichi has shown significant support for nuclear energy since she took office last year. In April, Toyko Electric Power Company resumed commercial operations at Unit 6 of the Kashiwazaki-Kariwa nuclear power plant. It was the first commercial restart of one of TEPCO's reactors since the Fukushima accident. TEPCO plans to restart Kashiwazaki-Kariwa-7 by 2030.