TOKYO (Reuters) - Japan's Chubu Electric Power Co said it will delay building a sixth nuclear reactor at its Hamaoka plant 200 km (125 miles) southwest of Tokyo by one year, until 2016, as it reviews safety and power supply plans after this month's quake and tsunami in northeast Japan.
Japan's No.3 power company said it was sticking, however, to its broad target of putting the new reactor into commercial operation by March 2024, and to its long-term business strategy announced last month of building a second nuclear plant with 3,000 to 4,000 megawatts of capacity by 2030.
"We're putting a higher priority on (safety of) the existing reactors. We've decided to review our plans for the No.6 unit," Chubu Electric Executive Officer Kazuhiko Okabe told a news conference.
But he added: "We think the status of nuclear power as an option among our necessary energy sources is unchanged."
Concerns over nuclear safety have heightened as engineers struggle to prevent meltdowns and radiation leaks at a six-reactor plant operated by Tokyo Electric Power Co in Fukushima, 250 km north of Tokyo, that was knocked out by the March 11 tsunami.
Chubu said it would build a 12-meter tsunami wall over the next few years to protect the coastal Hamaoka plant, located in the Tokai region where the government has been preparing for the possibility of a major earthquake.
Academics have been warning since the 1970s that the area has been hit regularly by magnitude 8-plus earthquakes every 100 to 150 years, with the last occurring in 1854.
Okabe said the plant met tightened government safety regulations adopted after a 2007 quake crippled a Tokyo Electric nuclear plant in northern Japan, and that a simulation based on historic data showed any tsunami following a quake in the area would be no higher than 8 meters.
The central Japan utility also said on Wednesday that it would delay reopening Hamaoka's No.3 reactor by one week, to carry out emergency training to prepare for a potential loss of power of the sort that triggered the crisis at Fukushima.
Chubu runs three boiling water reactors at the Hamaoka plant with a total capacity of 3,617 MW and is preparing to close down two older reactors which have already been taken out of operation.
Chubu's reliance on nuclear power is relatively low among Japanese utilities, at 14 percent. Tokyo Electric generates about 30 percent of its power from nuclear plants.
Chubu and other utilities in Japan's undamaged west have sent staff and equipment to the northeast, where Tokyo Electric and Tohoku Electric Power Co face power crunches after several of their plants were damaged.
Chubu has said it diverted 60,000 metric tons of liquefied natural gas (LNG) to Tokyo Electric and is considering supplying Tohoku Electric as well.
But unlike Europe, where power grids are connected across national borders, a bottleneck in Japan's fragmented system prevents sharing of power between the west, with a power frequency of 60 hertz, and the 50 hertz east.
There are three linkage facilities between the east and the west with total capacity of 1,000 MW, but that is at most 10 percent of the power shortfall faced by the two disaster-struck utilities in the east, forcing them into rolling blackouts.
With power demand set to increase in the summer, analysts expect a worsening impact on the economy from new rounds of power blackouts in the areas that Tokyo Electric serves, which account for 40 percent of Japan's GDP.
Chubu Electric said on Wednesday it had switched the frequency of a small portion of its hydropower capacity to 50 hertz from 60 hertz, allowing it provide up to 270 MW of power to its peers to the east.
It also plans to increase capacity at its east-west linkage facility in Higashi Shimizu, near the Hamaoka plant in Shizuoka prefecture, to 130 MW from 100 MW by May, and is considering speeding up plans for a further increase to 300 MW, currently set for December 2014.
(Reporting by Risa Maeda; Editing by Edmund Klamann)