Japan to Have Surplus Power in Summer Without Additional Nuclear

Japan may have enough electricity supply to meet peak demand this summer without the need to restart idled nuclear reactors, a government report said.

Nine regional utilities will have 6.3 percent surplus supply capacity on average in August, when demand peaks, according to the report today that cites data submitted by the companies. Kansai Electric Power Co., the utility most dependent on nuclear power, is expected to have 3 percent excess capacity in the three months ending September, the report said.

Japan, which got about 30 percent of its electricity from nuclear power before the March 2011 Fukushima disaster, has 48 reactors lying idle. The nation restarted Kansai Electric’s two units at the Ohi plant last July to avoid power shortages in summer months. Reactors will have to pass new safety standards, which will be set by the Nuclear Regulation Authority in July, before being restarted.

The report assumed none of the idled 48 reactors will be restarted before summer.

Tokyo Electric Power Co., which supplies electricity to Japan’s most industrialized area, will have 6.7 percent surplus capacity in August. Kyushu Electric Power Co.’s supply capacity will be at least 3 percent above peak demand in summer, the report said.

Surplus Guidelines

Utilities should have at least 3 percent surplus capacity to deal with momentary demand spikes. It is “desirable” for utilities to have excess capacity of between 7 percent and 8 percent in case of accidents at power plants and higher-than-expected temperatures, according to government guidelines.

The Japanese government set summer power-saving targets in areas supplied by seven of 10 regional utilities last May. Households and companies in the Kansai region, Japan’s second biggest metropolitan area, needed to cut power usage by more than 15 percent, the government said at the time. The targets in some areas were reduced after one of the Ohi reactors was restarted in July.

The two reactors at the Ohi plant northeast of Osaka are scheduled to shutdown for checks in September. Under Japanese regulations, reactors have to undergo maintenance at least once every 13 months.

The Nuclear Regulation Authority plans to allow Kansai Electric to keep the two Ohi reactors in operation until the scheduled September maintenance, Chairman Shunichi Tanaka said March 19.

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