MINAMI-SOMA, Japan -- Another Japanese nuclear reactor was taken off line for maintenance on Monday, leaving the country with only one of its 54 reactors operational following last year's devastating earthquake and tsunami.
The last reactor is expected to be shut down by early May, raising the possibility of power shortages across the nation as demand increases in the hot summer months.
The No. 6 reactor at the Kashiwazaki-Kariwa complex, the world's biggest nuclear power plant, was taken off line early Monday by the Tokyo Electric Power Co. (Tepco)
The utility also runs the plant in Fukushima, northeast of Tokyo, that suffered meltdowns, explosions and radiation leaks after the March 11 quake and tsunami.
Japanese reactors are taken off line every 13 months for regular checks. With concerns over nuclear safety high following the Fukushima crisis, none of the reactors that have been shut down for checks, and none that were already off line at the time of the disaster, have been allowed to restart.
The last reactor, on the northern island of Hokkaido, will be shut down in May. The timing for when any reactors will be restarted remains unclear.
'Stress tests'
Before the crisis, Japan depended on nuclear power for one-third of its electricity. Japan's government wants to restart reactors as soon as "stress tests" prove they are safe, but faces strong public opposition. Local leaders, fearing a political backlash, are reluctant to give their approval.
Authorities have required all reactors to undergo the stress tests and make necessary modifications to improve safety. The stress tests, similar to those used in France and elsewhere in Europe, are designed to assess how well the plants can withstand earthquakes, tsunamis, storms, loss of power and other crises.
"We are likely to be able to provide stable electricity supply at the moment, but we would like to ask customers to continue conserving power," Tepco President Toshio Nishizawa said in a statement released on Sunday. "We are currently closely studying the summer power supply situation. We will do our utmost to operate in a stable way and maintain our facilities."
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'Invisible' impact?
Greenpeace Japan's Executive Director Junichi Sato said that the country could survive without rushing to restart its nuclear sector.
"Japan is practically nuclear-free, and the impact on daily life is invisible," Sato said in a statement.
"With proper demand management, energy efficiency measures, and more than sufficient backup generation in place, there is no excuse for shortages in the coming months, and absolutely no need to rush restarts of nuclear plants."
To avoid blackouts, utilities have restarted old fossil fuel plants.
The Associated Press and Reuters contributed to this report.
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