Japan suspended the restart of the world’s largest nuclear power plant on Thursday after an alarm went off during reactor startup procedures. The Kashiwazaki-Kariwa plant in Niigata province had been offline since the 2011 Fukushima disaster. TEPCO, the plant operator, said it does not know when the issue will be resolved.
TEPCO reported that a monitoring system alarm triggered the halt, prompting an investigation of malfunctioning electrical equipment. Control rods were reinserted in a planned manner, keeping the reactor stable. Officials confirmed there was no radioactive impact outside the plant.
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The restart, originally scheduled for Tuesday, had already been delayed due to a technical problem with the reactor’s control rods. Only one of the plant’s seven reactors was being restarted. Kashiwazaki-Kariwa is the first TEPCO-run unit to resume operations since 2011.
Japan aims to revive nuclear power to reduce reliance on fossil fuels, achieve carbon neutrality by 2050, and meet growing energy demand driven by artificial intelligence. However, public opinion in Niigata remains divided, with around 60% opposing the restart and 37% supporting it.
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Safety concerns remain high, as the plant sits near an active seismic fault zone and experienced a strong earthquake in 2007. Earlier this month, seven local groups submitted a petition with nearly 40,000 signatures to TEPCO and the Nuclear Regulation Authority opposing the restart.