Two Japanese power companies said they will seek final approval for commercial operation of nuclear reactors that have been operating in a grey zone since their restart in March, aiming to lift uncertainty over their status as Japan grapples with potential power shortages.
Kansai Electric Power and Hokkaido Electric Power said on Wednesday they were preparing applications for last-stage inspections of reactors that had been shut for maintenance and restarted just days before the March 11 earthquake, which triggered a nuclear crisis at Tokyo Electric Power's Fukushima plant in northeast Japan.
Nuclear reactors typically get formal approval for commercial operations about a month after restarting in test mode, during which time they can still generate and supply electricity normally, but the utilities delayed the process for fear that local authorities would object to final approval as the Fukushima crisis stirred worries over nuclear safety.
Safety worries have also prevented the restart of any nuclear reactors off-line for routine maintenance since the March disaster, fuelling fears of a power crunch and raising the possibility that, as more reactors are taken down for checks, Japan could be completely without nuclear power by next spring.
Nuclear reactors supplied about 30 percent of Japan's electricity before the Fukushima crisis.
STRESS TESTS
To help ease public concerns, authorities are planning a series of stress tests at all of the country's nuclear plants to confirm their safety and determine their ability to withstand extreme events, including earthquakes and tsunamis that exceed their designed capacity.
Kansai Electric's 1,175-megawatt Ohi No.1 unit and Hokkaido Electric's 912-MW Tomari No.3 unit were restarted just days before the disaster struck Japan's northeast coast.
Although they have been supplying power to customers, the lack of final approval for commercial operation left open the possibility that they could be forced to halt operations again, while putting in doubt the schedule for their next maintenance shutdown, usually required within 13 months of the start of commercial operation.
The two firms said they decided to move forward after the Nuclear and Industrial Safety Agency (NISA), the nuclear watchdog under the trade ministry, instructed them last Friday to complete the final tests and get final approvals.
Japanese media reported that prefectural governors have not expressed opposition to the final approvals, with the reactors already in operation for several months, while a Kansai Electric spokesman said the approval for its Ohi reactor would be a matter between the utility and the central government.
Spokesmen for the two firms said there was no schedule yet for submitting applications and completing the final tests, but domestic media said the government could give the go-ahead as early as this month.
A NISA official said the schedule for the two reactors' next maintenance shutdown would likely take into account that they have been running for four months, suggesting that the 13-month limit could kick in from the original scheduled restart of commercial operations in early April, with shutdowns likely by early May 2012.
