Government wants to see more reactors online in face of energy crunch Takahama-3 and Takahama-4 in western Japan both began commercial operation in 1985. Kansai Electric Power will apply for regulatory approval to extend the operating life of its Takahama-3 and -4 nuclear power units by a further 20 years, potentially operating both plants for the maximum 60 years.

The company also said it is planning to replace the steam generators at the two 830-MW pressurised water reactor units in Fukui prefecture, western Japan.

Under safety rules which came into force after the Fukushima-Daiichi accident, Japanese reactors have an operating period of 40 years. One extension to this – limited to a maximum of 20 years – may be granted, but requires a special inspection to verify the integrity of reactor pressure vessels and containment vessels after 35 years of operation.

Takahama-3 and Takahama-4 both began commercial operation in 1985.

Two other unts at the site, Takahama-1 and -2, became the first Japanese units to be granted a licence extension beyond 40 years under revised post-Fukushima regulations, but are out of service pending the completion of a bunkered backup control centre, as required by the regulator. Kansai has said it plans to restart the units, both 780-MW pressurised water reactors, in mid-2023.

In October, utility Kyushu Electric Power applied to extend the operational lifetime of Units 1 and 2 at the Sendai nuclear power station in southwestern Japan by 20 years to 60 years.

Reports in Japan have said the industry ministry is considering extending the lifespan of nuclear reactors to beyond the current 60 years with ambitions to finalise the plan by the end of the year.

The plan is part of the government’s efforts to cut carbon emissions and ensure stable energy supplies threatened by Russia’s war in Ukraine, the reports claimed.

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.

Tokyo Also Looking At Next-Gen Reactors

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.

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.

The change of direction has highlighted Japan’s struggle to secure a stable energy supply as a result of the war in Ukraine and higher energy costs.

Japan has seen 10 commercial nuclear reactors return to service since Fukushima-Daiichi. Another 17 reactors have applied to restart.

According to the Tokyo-based Japan Atomic Industrial Forum (Jaif), the reactors that have returned to service are Genkai-3, Genkai-4, Ikata-3, Mihama-3, Ohi-3, Ohi-4, Sendai-1, Sendai-2, Takahama-3 and Takahama-4.

However, Jaif told NucNet that only five of those are operating. The other six are undergoing inspections and safety updates.

The units in operation are Takahama-3, Ohi-4, Ikata-3, Sendai-1 and Sendai-2.