The law on power sources for green transformation and decarbonization amends five laws associated with energy at once, including the electricity business law, under which the life span of reactors will be regulated.
Following the 2011 Fukushima disaster, Japan introduced stricter safety standards under the reactor regulation law, which limits the duration of a nuclear reactor to 40 years, in principle, and up to 60 years if proper safety upgrades are made.
But under the new rules, nuclear reactors may be granted additional operating years in effect as their offline periods will not be counted against their total service time provided the periods are due to reasons beyond a utility's control, such as safety reviews needed for a restart and court-ordered suspensions.
The industry minister will give approval for extending the life of nuclear reactors on a case-by-case basis.
In addition, under the amended reactor regulation law, the country's Nuclear Regulation Authority will check the condition of reactors and related facilities at least every 10 years after 30 years of operating to ensure the safety of old facilities.
"These (old) reactors will not become operable unless they pass the NRA's reviews within every 10 years and obtain approvals," Economy, Trade and Industry Minister Yasutoshi Nishimura told a press conference Tuesday.
Nishimura added that a running total of online time for reactors will still be 60 years.
The government has said it will decide the details of standards for granting extension after the law is enacted.
Meanwhile, critics have pointed out that specific ways to assess the age-related deterioration of reactors beyond 60 years of operation, among other issues, remained unclear.
Russia's war in Ukraine, which started in late February 2022, drove energy prices sharply higher and threatened stable energy supplies for Japan -- a resource-scarce country that relies heavily on fossil fuel imports -- prompting officials to look into greater use of nuclear power.
Prime Minister Fumio Kishida said last summer the government will take necessary measures to restart nuclear power plants, instructing the government to look into how the country can maximize its nuclear energy facilities most effectively.
