Japan's Kyushu Electric Power Co on Friday said it restarted a reactor at its Genkai plant, the fifth nuclear power station in the country to get cleared under new safety regulations imposed after the Fukushima disaster.
The move signals that Japan's return to nuclear power - criticized by some as too slow but still opposed by a majority in opinion polls - is gathering pace. The country may have as many as eight reactors operating by early June, representing 20 percent of available units.
All of the restarted reactors are located in western Japan, far from the northeast coast where Tokyo Electric Power Co's Fukushima Daiichi station had three reactor meltdowns after an earthquake and tsunami knocked out power and cooling, causing 160,000 people to flee, many of them never to return.
"Japan's baseload power capacity is gradually being re-established after the 2011 disaster with the reactor restarts in western Japan," said Tom O'Sullivan, managing director of energy consultancy Mathyos Japan.
"This should bring some relief to Japan's power companies heading into the warmer period, when Japan normally experiences its peak load requirements," O'Sullivan said.
Kyushu Electric said it also aims to restart the No. 4 reactor at Genkai in May. The No. 3 unit, restarted on Friday, had been idled for more than seven years.
Kyushu Electric, which services the island of the same name, also plans to restart the No. 1 reactor at its Sendai plant, once it completes scheduled maintenance and refuelling. That unit was the first to restart in Japan after the industry shutdown.
Once those reactors start running, all the units it has sought restart approval for will be operating.
Kansai Electric Power, Japan's most nuclear-reliant utility before Fukushima, has three reactors operating and is also aiming to restart a fourth in May.
"Moving forward the challenge may be in eastern Japan where no reactors have been restarted," said O'Sullivan.
(Reporting by Osamu Tsukimori and Aaron Sheldrick; Editing by Tom Hogue)