Restart Halted After Safety Alarm Failure
The highly anticipated restart of Unit 6 at the Kashiwazaki-Kariwa nuclear power plant in Japan, operated by Tokyo Electric Power Company Holdings Inc. (TEPCO), has been delayed from its scheduled date of January 20, 2026. The postponement follows the detection of an alarm malfunction during pre-reactor start-up checks conducted on Saturday, January 17.
The incident occurred during a control rod withdrawal test, where an alarm designed to prevent unintended withdrawal failed to activate when a second control rod was selected while another was already being withdrawn. TEPCO promptly investigated the issue, identifying an error in the settings for the second control rod withdrawal prevention function. The company reported that the settings were corrected, and the alarm subsequently functioned properly, with the reactor returned to its pre-deviation state on Sunday, January 18, 2026, at 8:16 p.m.
Indefinite Postponement for Further Verification
Despite resolving the immediate alarm issue, TEPCO has opted to postpone the restart indefinitely. The utility stated that it requires additional time to conduct thorough verification checks on each of the 205 control rods within the No. 6 reactor and to examine the fission reaction of the fuel assemblies. A new date for the resumption of operations has not yet been announced.
Significance for TEPCO and Japan's Nuclear Industry
This planned restart of Unit 6 would have marked a significant milestone as TEPCO's first reactor to come back online since the devastating 2011 Fukushima Daiichi nuclear disaster. The Kashiwazaki-Kariwa plant, located in Niigata Prefecture, holds the distinction of being the world's largest nuclear power plant by net electrical power rating. Its return to operation is widely viewed as a crucial test for TEPCO's ability to manage nuclear facilities safely and for the broader Japanese nuclear power industry, which is seeking to enhance energy security and reduce reliance on fossil fuel imports.
Regulatory Approvals and Historical Context
Units 6 and 7 of the Kashiwazaki-Kariwa plant received approval from Japan's Nuclear Regulation Authority (NRA) in December 2017, confirming their compliance with new regulatory standards established after the Fukushima accident. Fuel loading for Unit 6 was completed in June of the previous year, and the local government of Niigata Prefecture had also granted its approval for the restart. All units at the Kashiwazaki-Kariwa complex have been offline since the Fukushima disaster, with Unit 6 entering regular inspection in March 2012. The plant also underwent extended shutdowns following the 2007 Niigata-Chuetsu earthquake.
5 Comments
Donatello
Another nuclear delay, another safety scare. This is unacceptable.
Raphael
Just scrap it. Nuclear is too risky, especially when operated by TEPCO.
Leonardo
While it's disappointing to see another delay for Japan's energy plans, prioritizing safety checks on all control rods is absolutely critical after past incidents. It's a necessary step to rebuild public trust, even if it causes further setbacks.
Donatello
Responsible decision to halt and re-check every single rod. This rigor is key.
Leonardo
On one hand, strict regulatory oversight and TEPCO's decision to re-verify everything is a positive sign for safety protocols. On the other hand, the continuous string of issues and delays makes one wonder if nuclear power is truly a viable long-term solution for Japan's energy needs without constant problems.