Japan is going through its first winter without nuclear power since the March 2011 meltdowns at Tokyo Electric Power Co.’s Fukushima No. 1 plant. All of the nation’s 50 nuclear power reactors have remained offline since the Nos. 3 and 4 reactors at Kansai Electric Power Co.’s Oi plant in Fukui Prefecture were shut down for maintenance last September.
The Nuclear Regulation Authority, which examines idled nuclear power plants that utility firms want to restart, must proceed strictly on scientific grounds — focusing on whether their restart plans comply with the new safety regulations, introduced in 2013, that incorporated lessons learned from the Fukushima nuclear disaster. The NRA must not be swayed by political considerations.
As soon as the new safety regulations took effect last July, power companies rushed to apply for the NRA’s assessment of their plans to restart the reactors. Six months on, the NRA has under consideration seven utilities’ plans to restart a total of 16 reactors at nine plants across the country.
The assessment process is taking longer than was initially thought due partly to delays on the part of the power companies preparing massive volumes of paperwork. It remains uncertain how soon the NRA will conclude its examination of any nuclear power plant included in the plans.
Under the new standards — billed as the world’s toughest nuclear regulations — utilities are obliged to install specific countermeasures for major contingencies ranging from core meltdowns to tsunamis.
Reactors will be required to be equipped with a filtered venting system to reduce the amount of radioactive substances released into the environment when pressure needs to be vented from a reactor core during emergencies.
But pressurized water reactors, used mainly at plants in western Japan, have been given a five-year grace period to meet the requirement. (Most of the reactors used in eastern Japan, including Fukushima reactors, are boiling water reactors.)
Utilities are also required to make a strict assessment of whether geological faults running underneath nuclear plants are active, a factor that would result in permanent shutdown of reactors.
Power companies have reason to hurry. They need to restart nuclear power plants to reduce the massive cost of imported fuel for increased thermal power generation, which has been making up for the shutdown of nuclear plants.
The Abe administration, which now calls nuclear power an “important baseload power source” for the nation’s energy supply stability, says it is ready to reactivate reactors that have passed the NRA’s examination once the consent of local authorities hosting the power plants is obtained.
More utilities are expected to apply to restart their plants. Japan Nuclear Fuel Ltd. also recently filed for NRA screening of its spent nuclear fuel reprocessing plant and related facilities in its complex at Rokkasho, Aomori Prefecture.
Assessment of the Rokkasho facilities will be made according to a separate set of safety regulations that took effect in December. That work is expected to take longer because of the complicated process of spent-fuel reprocessing and the sheer number of facilities to be examined.
Manpower support for the NRA will be needed if the screening process becomes backlogged due to staff shortages or work overloads. NRA assessment is a crucial process toward ensuring that nuclear power plants are adequately safe and can withstand major disasters on the basis of the experience with the Fukushima disaster. The NRA needs to point out any safety shortcomings in the utilities’ plans and get them corrected before approving the restarts.