Units could potentially remain online until 2045
Kansai Electric Power has asked Japan's Nuclear Regulation Authority (NRA) for permission to extend the lifespan of its Takahama-3 and -4 nuclear power plant by 20 years, potentially keeping them online until 2045.
Under existing regulations, Japan’s commercial nuclear reactors have a nominal operating period of 40 years. An extension of up to 20 years can be granted, but requires a special inspection to verify the integrity of reactor pressure vessels and containment vessels after 35 years of operation.
Kansai said it had carried out special inspections and evaluations of the two units and not found any issues likely to cause problems if the operating period was to be extended to 60 years.
The company said in a statement it had put together a facility management programme for the extended operation including the replacement of the steam generators. The statement added: “We will continue to strive to improve the safety and reliability of nuclear power plants and with the understanding of the local community and others we will utilise nuclear power generation as an important power source.”
The Takahama nuclear station, in Fukui prefecture, western Japan, is home to four reactors. Takahama-1 and -2 are both 780 MW pressurised water reactors (PWRs) that entered commercial operation in 1974 and 1975 respectively. Takahama-3 and -4 are both 830 MW PWRs.
Takahama-1 And -2 ‘To Restart This Year’
Takahama-1 and -2 became the first Japanese units to be granted a licence extension beyond 40 years under revised regulations, but are offline pending the completion of a bunkered backup control centre, as required by the regulator. Kansai has said it plans to restart Units 1 and 2 in mid-2023.
In December the NRA approved new regulations that will allow commercial reactors to operate longer than the limit of 60 years as the nation looks to increase the share of power generated by nuclear energy.
The Japan Times said the government aims to introduce legislation to allow for longer reactor operation during this year’s parliamentary session, where “a tough debate between supporters and opponents of extending the use of nuclear power is likely”.
All the country’s commercial reactors were shut down following the 2011 Fukushima disaster and are not allowed to restart until they have passed stringent new safety checks.
Before Fukushima-Daiichi, Japan’s fleet of 54 nuclear plants generated about 30% of the country’s electricity. According to the International Atomic Energy Agency that figure was 7.2% in 2021.
The Japan Atomic Industrial Forum, a Tokyo-based industry group, said on Thursday (27 April) that among the 33 operable nuclear reactors in Japan, 10 have resumed operations after meeting post-Fukushima safety standards, while 10 are still under examination by the NRA. The restarted plants are: Sendai-1 and -2, Genkai-3 and -4, Ikata-3, Mihama 3, Ohi-3 and -4 and Takahama-3 and -4.
Japan has said it will restart more idled nuclear plants and look at developing next-generation reactors as well as extending the lifespan of existing reactors in a major policy shift on nuclear energy a decade after Fukushima.