Oldest commercial reactor in country went online in 1974
Japan’s Nuclear Regulation Authority on Wednesday (16 October) approved the Takahama-1 nuclear power plant to continue operations for the next 10 years, making it the country’s first reactor to be endorsed to operate beyond 50 years.
The regulator confirmed owner and operator Kansai Electric Power Company’s assessment that the plant is safe to operate. It also approved Kansai Electric’s plan for ageing countermeasures at the unit over the next 10 years.
The 780-MW Takahama-1 pressurised water reactor unit, in Fukui Prefecture, western Japan is the oldest operational nuclear power reactor in the country. It began commercial operation in November 1974.
Kansai Electric applied to the NRA in November last year to operate the plant for a further 10 years after conducting an ageing technical evaluation and formulating a long-term facility management policy.
The Takahama station has four units, all of which have been restarted since the 2011 Fukushima-Daiichi disaster. Takahama-1 was restarted in July 2023 after being offline since January 2011.
Before Fukushima, Japan’s fleet of 54 nuclear plants generated about 30% of the country’s electricity, but were all shut down for safety checks following the accident.
Among the 33 operable nuclear reactors in Japan, 12 have now resumed operations after meeting post-Fukushima safety standards. The restarted plants are: Sendai-1 and -2, Genkai-3 and -4, Ikata-3, Mihama-3, Ohi-3 and -4 and Takahama-1, -2, -3 and -4.
Earlier this week, Chugoku Electric Power Company said its Shimane-2 nuclear power plant in Shimane Prefecture, southwest Japan, will restart in early December, a move that will bring the number of reactors online to 13 and boost the nation’s power supply this winter.
Under regulations which came into force in July 2013, Japanese reactors had a nominal operating period of 40 years. One extension to this – limited to a maximum of 20 years – could be granted, bringing the maximum to 60 years.
In December 2022, the NRA approved a new rule that would allow reactors to be operated for more than 60 years. The rule effectively extended the amount of time reactors can remain operational beyond 60 years by excluding time spent on inspections and other periods they are offline from consideration when calculating their total service life. Japan’s cabinet formally adopted the new rule in February 2023.
