TOKYO, November 27, 2025 – Japan’s Kashiwazaki-Kariwa nuclear power plant, the largest nuclear facility in the world, could resume operations as early as January 2026, pending approval from regional authorities, according to Jiji news agency. This potential restart represents a significant milestone for Japan’s nuclear energy sector, which has been gradually recovering after the 2011 Fukushima Daiichi disaster.

Regional Approval Moves Forward

A regional governor in Niigata Prefecture recently approved a partial restart of the Kashiwazaki-Kariwa plant. The prefecture’s assembly is scheduled to vote on this decision during its regular session starting December 2, 2025. If the assembly grants its approval, the plant’s Unit 6—one of the two largest reactors at the facility—could potentially resume operations in January 2026, according to plant director Takeyuki Inagaki.

TEPCO’s Next Steps

Following the assembly’s approval, Tokyo Electric Power Company Holdings Inc. (TEPCO), the plant operator, will formally apply to Japan’s Nuclear Regulatory Commission (NRC) for a pre-use confirmation of Unit 6. The regulatory review process generally takes between three weeks to a month, providing a clear timeline for the anticipated restart.

This potential restart would mark TEPCO’s first nuclear operation since the 2011 Fukushima disaster, which led to widespread nuclear shutdowns across Japan and ongoing compensation obligations for the company. The move reflects Japan’s efforts to revive its nuclear sector and reduce reliance on imported fossil fuels amid growing energy security concerns.

Implications for Japan’s Energy Sector

The planned restart of Kashiwazaki-Kariwa underscores the Japanese government’s commitment to nuclear power as a key energy source. By bringing one of the world’s largest nuclear plants back online, Japan aims to:

• Reduce fossil fuel imports and strengthen energy independence.
• Enhance regional energy supply stability in Niigata Prefecture and beyond.
• Support the country’s climate and sustainability goals by relying on low-carbon energy sources.

Industry analysts suggest that the successful restart of Unit 6 could pave the way for additional units at Kashiwazaki-Kariwa to resume operations, gradually re-establishing Japan’s nuclear capacity and helping the country meet rising electricity demand.

Looking Ahead

As Japan balances energy security, economic growth, and environmental considerations, the Kashiwazaki-Kariwa restart is seen as a crucial step toward revitalizing its nuclear power sector. TEPCO’s ability to safely operate the plant will be closely monitored by regulators, local authorities, and international observers, marking a pivotal moment in Japan’s post-Fukushima energy strategy.