Japan Suspends Nuclear Restart After Alarm Sounds

---

Written by Martin Lynch, European News Editor for IIR News Intelligence (Sugar Land, Texas)

---

Summary

Japan's Tokyo Electric Power Company (TEPCO) has been forced to abandon the process of restarting the world's largest nuclear power plant, 14 years after it was shut down in the wake of the 2011 Fukushima-Daiichi nuclear accident.

---

False Start for Nuclear Restart

Japan's accelerated return to nuclear power with the restart of a reactor at the world's largest nuclear power plant, Kashiwazaki-Kariwa, lasted just hours after an alarm sounded and the process was ended. 

The country's government ordered the shutdown of all nuclear plants in 2011 after the Fukushima accident. The controversial restart of the Unit 6 reactor at Kashiwazaki-Kariwa was greenlit in late December, but hours after the startup procedures began on January 22, which involved removing fission rods, an alarm sounded and the process was abandoned. Takashi Kobayashi, a spokesperson for owner and operator, Tokyo Electric Power Company (TEPCO), confirmed that "an alarm from the monitoring system... sounded during the reactor startup procedures, and operations are currently suspended". He said that the reactor "is stable and there is no radioactive impact outside. We are continuing to investigate the cause of the control rod operation monitoring system alarm that occurred during the control rod withdrawal operation." No date has been given for the restart at the seven-reactor, 8.2-gigawatt (GW) facility. TEPCO, which also owns the infamous Fukushima nuclear plant, has petitioned for more than a decade for the restart of two units at the Kashiwazaki-Kariwa plant. 

Nuclear Power in Japan Today

At the time of the Fukushima accident, Japan had 54 operational nuclear reactors supplying around 30% of the country's power. After the accident, most were shut down over the following year. Since then, 14 reactors have been slowly brought back online, and in 2023 nuclear power supplied 8.5% of the country's power. A successful restart was seen as vital to speed up Japan's return to nuclear power as the country currently needs to import roughly 90% of its energy requirements. Industrial Info is tracking 80 nuclear power related projects in Japan worth US$35 billion, only one of which is a new-build. Subscribers to Industrial Info's Global Market Intelligence (GMI) Project Database can click here for the reports.

Political Fallout?

Returning to nuclear power has been a key platform for recent Japanese governments. Last 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. The main argument is that Japan needs nuclear back online to offset its almost complete reliance on fossil-fuel imports and to help the country transition to renewables. Industrial Info reported in October that the country's new Prime Minister Sanae Takaichi was 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.

Prime Minister Pushes For Energy Revamp

In recent weeks, Industrial Info has reported on Prime Minister Takaichi's call for snap elections in early February which could give her more power over driving through her energy reforms. Takaichi, Japan's first woman prime minister, has called the snap elections two years early on the back of sky-high approval ratings with voters. It is unclear if the failed restart of Kashiwazaki-Kariwa will sway opinion against her energy policies. For additional information, see January 21, 2026, article - Japan PM's Snap Elections Could Strengthen Her Energy Policy. Just days after she took office, she hosted U.S. President Donald Trump and signed an agreement involving investments in critical minerals for security purposes. And in December, Japan was included in a White House meeting with eight allies, also regarding critical minerals security based on reducing dependence on China. For more on that, see December 11, 2025, article - U.S., Allies Seek to Lessen China's Hold on Critical Minerals.

Key Takeaways 

• Alarm sounds during the crucial restart of Japan's Kashiwazaki-Kariwa nuclear plant, forcing the process to be abandoned.
• Kashiwazaki-Kariwa, the world's largest nuclear power plant, has been shut for 14 years since the 2011 Fukushima-Daichii nuclear accident.
• Japan relies on energy imports for roughly 90% of its power.

---

About IIR News Intelligence
IIR News Intelligence is a trusted source of news for the industrial process and energy markets, powered by Industrial Info Resource's Global Market Intelligence (GMI).

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 250,000 current and future projects worth $30.2 Trillion (USD).

---