Sudden Shutdown: World’s Largest Nuclear Plant Pauses Operations Hours After 2026 Restart

Japan’s TEPCO announced on Thursday, January 22, 2026, the suspension of Unit 6 at the Kashiwazaki-Kariwa nuclear power plant—the world’s largest by capacity. The shutdown occurred just hours after the reactor was brought back online for the first time in 14 years. An alarm was triggered at 12:28 a.m. local time during the withdrawal of control rods, leading the operator to halt operations for a thorough investigation into a suspected system malfunction.

The Nuclear Regulation Authority confirmed the reactor is "stable" and no radiation leaks have been detected. This technical glitch follows a series of delays, including a previous alarm failure last weekend. The restart is a key part of Japan’s 2026 energy strategy to achieve carbon neutrality, yet it remains controversial, with local polls showing significant public concern over the plant's location in a seismically active zone.