Japan restarts world’s biggest nuclear plant in Niigata

Japan’s nuclear power industry has been rocked by a series of scandals and safety lapses in recent weeks, including revelations that Chubu Electric Power falsified data to downplay seismic risks.

At the Kashiwazaki-Kariwa plant, Tokyo Electric Power Company (TEPCO) disclosed on Saturday that an alarm system malfunctioned during a recent test.

“Safety is an ongoing process, which means operators of nuclear facilities must never become arrogant or overconfident,” TEPCO President Tomoaki Kobayakawa told the Asahi Shimbun in an interview.

Japan remains the world’s fifth-largest emitter of carbon dioxide, trailing only China, the United States, India, and Russia. The country continues to rely heavily on imported fossil fuels, which accounted for nearly 70 percent of its electricity in 2023. Tokyo aims to cut that share to between 30 and 40 percent within the next 15 years by boosting renewable and nuclear energy.

Under a government plan approved in February, nuclear power is expected to contribute about 20 percent of Japan’s energy mix by 2040—up from roughly 8.5 percent in fiscal year 2023–24.

At the same time, Japan faces the ongoing challenge of decommissioning the Fukushima Daiichi nuclear plant—a complex and costly effort projected to take several decades to complete.