Japan's industry ministry is considering extending the lifespan of nuclear reactors to beyond the current 60 years with ambitions to finalize the plan by the end of the year, in a bid to cut carbon emissions and ensure stable energy supplies threatened by Russia's war in Ukraine, sources familiar with the matter said Tuesday.

The Ministry of Economy, Trade and Industry is looking to extend the number of years nuclear power stations can remain open by considering screening periods, necessary for stricter plant safety operations, as separate from the total service life, which could allow nuclear reactors to operate for longer. During safety checks, the nuclear plants are not operational.

A ministry panel is set to discuss extending the service life of the nuclear power stations in such a way as a main scenario among other options, with plans to finalize their decision by the end of the year, the sources said.

Under the current safety rules, the Nuclear Regulation Authority limits nuclear reactors' service period to 40 years in principle. If approved by the regulatory body however, the period can be extended by up to 20 years.

The panel will also look at scrapping the 60-year lifespan, as well as maintaining the current rules as two alternative options, in case the proposal is found not to be viable.

File photo shows Hokkaido Electric Power Co.'s Tomari nuclear power plant in Tomari, Hokkaido, in September 2018. (Kyodo)  

Prime Minister Fumio Kishida said in August that Japan will push ahead with the use of nuclear power, citing the plan as an option to achieve net-zero emissions and secure a stable electricity supply.

Japan relies heavily on fossil fuel imports for power generation, with its energy self-sufficiency rate standing at 12.1 percent as of fiscal 2019, lower than many other developed countries.

Nuclear power plant operators must pass the tougher regulations to restart their reactors after a nationwide halt which occurred after the Fukushima nuclear disaster of March 11, 2011, which was caused by a massive earthquake and tsunami. Only a handful of reactors in Japan have since resumed operations, while the public remains concerned over their safety.

Some utilities face prolonged screening processes by the NRA. More than nine years have passed since the safety examinations of Hokkaido Electric Power Co.'s Tomari nuclear power plant began, for example.

The electric power industry has urged more than 60 years of service will be safe provided appropriate maintenance operations are guaranteed.

The safety watchdog proposed earlier this month that the safety of nuclear plants aged 30 years or older, regardless of whether a reactor lifespan is extended, be checked at least once a decade to obtain approval for their continued operation.

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