Japan Halts Restart of Its Largest Nuclear Power Facility

The operation to restart the globe's largest nuclear power station has been put on hold in Japan, just a single day after it resumed, as the managing company stated it is unclear when the issues will be rectified.

The Kashiwazaki-Kariwa Nuclear Power Plant had remained offline since the 2011 Fukushima disaster but commenced restart procedures last Wednesday following the final nod from regulatory bodies. However, on Thursday, the Tokyo Electric Power Company (TEPCO) revealed that an alarm was activated during the startup phase, leading to a suspension of the operations.

"An alarm from the monitoring system activated during the reactor startup processes," the company explained. Site superintendent Takeyuki Inagaki informed reporters, "We do not anticipate this to be resolved within a day or two. At this moment, we cannot assess how long it will take. Our immediate focus will be to pinpoint the cause of the incident."

TEPCO spokesperson Takashi Kobayashi noted that the alarm prompted engineers to examine malfunctioning electrical components. "Once it became apparent that a resolution would take time, we made the decision to gradually reinsert the control rods," he said, assuring that the reactor "is stable and poses no radioactive risk to the external environment."

Control rods serve crucial functions in managing the nuclear chain reaction in a reactor; they increase the reaction rate when partially withdrawn and decrease or halt it when fully inserted. The restart process had already encountered delays from Tuesday due to a separate technical problem related to the rod removal system, which TEPCO reported was resolved on Sunday, January 18.

Located in Niigata Prefecture, the Kashiwazaki-Kariwa facility is recognized as the largest nuclear power plant globally by available capacity, although only one of its seven reactors was part of the restart initiative. The plant was shut down when Japan halted nuclear activities nationwide after the earthquake and tsunami in 2011 caused meltdowns at the Fukushima Daiichi Nuclear Power Plant.

Lacking natural energy resources, Japan has been striving to reinstate nuclear power to reduce fossil fuel reliance, cater to the growing electricity demand driven by artificial intelligence advancements, and achieve carbon neutrality by 2050. Kashiwazaki-Kariwa is the first TEPCO-managed unit to attempt a restart since the 2011 incident, as the company continues its decommissioning efforts at Fukushima Daiichi.

Public opinion remains mixed in Niigata. A survey conducted in September indicated that about 60% of residents opposed the restart while only 37% were in favor. "The electricity produced at Kashiwazaki is for Tokyo, so why should we be put at risk here? It doesn’t seem logical," remarked 73-year-old Yumiko Abe during a protest outside the facility this week.

Earlier this month, seven organizations opposing the restart delivered a petition, signed by nearly 40,000 individuals, to TEPCO and Japan's Nuclear Regulation Authority, highlighting that the plant sits on an active seismic fault line and pointing to damage from a major earthquake that hit the region in 2007.