New Standard on Operating Period of N-plants; Hiatus Caused by Operator Fault Not Eligible for Inclusion in Extension

The Yomiuri Shimbun

6:00 JST, March 26, 2025

The Economy, Trade and Industry Ministry presented a draft of a new standard on nuclear power plants to its expert panel on Monday.

The draft states that if the cause of a halt in nuclear power plant operations is the fault of the plant operator, the plant’s operating life cannot be extended by the period during which operations were halted.

The ministry presented the draft, which is related to the criteria for granting extensions for nuclear power plant operations, to the panel ahead of the enactment in June of a law that will permit nuclear power plants to be operated beyond the current 60-year limit.

According to the draft, a plant’s operating life cannot be extended by periods in which the Nuclear Regulation Authority’s screenings are unable to proceed smoothly and the plant’s operator is found to be at fault.

In the wake of the accident at Fukushima No. 1 nuclear power plant in 2011, the operational period of nuclear power plants was limited to “40 years in principle or up to 60 years.”

However, a law on green transformation and decarbonization passed in 2023 has enabled nuclear power plant operators to effectively operate their plants beyond the 60-year limit by offsetting periods of non-operation due to safety checks and other essential works.

The ministry is compiling the draft ahead of the enactment of the law in June.

At the meeting of the expert panel, the ministry presented practical cases related to the new standard.

As examples of hiatuses that could not be used as extensions — because they were the fault of the operating companies — the ministry cited Tokyo Electric Power Company Holdings Inc.’s Kashiwazaki-Kariwa Nuclear Power Station in Niigata Prefecture and the Japan Atomic Power Co.’s Tsuruga Power Station Unit 2.

Screenings on the Kashiwazaki-Kariwa plant were delayed because parts of its anti-terrorism measures were found to be insufficient, while those on Unit 2 of the Tsuruga plant in Fukui Prefecture were suspended because documents were altered without permission.