Across Japan, utilities are backing the Abe administration’s support of nuclear power generation by continuing construction of a new facility and seeking to extend the life of reactors that have been operating for about 40 years.
Across Japan, utilities are backing the Abe administration’s support of nuclear power generation by continuing construction of a new facility and seeking to extend the life of reactors that have been operating for about 40 years.
Electric Power Development Co. (J-Power) announced Nov. 13 that it will apply to the Nuclear Regulation Authority for safety screenings to start operations at its Oma nuclear power plant, which is currently under construction.
The announcement came at a town assembly meeting at Oma, Aomori Prefecture, where J-Power President Masayoshi Kitamura said the company will submit the application by the end of the year and plans to have the new facility fully operational in fiscal 2021.
If everything proceeds as scheduled, the Oma plant will be the first instance in which power companies applied for the start of operations at new reactors that are still under construction.
While the No. 1 reactor at Tokyo Electric Power Co.’s Higashidori plant in Aomori Prefecture and Chugoku Electric Power Co.’s Shimane plant No. 3 reactor in Matsue are also currently under construction, the utilities have not submitted applications to start the reactors.
Although the central government's basic energy plan states that dependency on nuclear power should be reduced as much as possible, it does not clearly mention the construction of new nuclear facilities.
The government does not deem nuclear plants as “new or additional” if their construction started before the March 2011 Great East Japan Earthquake, which set off the nuclear disaster at the Fukushima No. 1 power plant.
Forty percent of the construction of the Oma plant had been completed prior to the disaster.
However, there is no guarantee that the screening process will proceed smoothly because the structure and operation procedures of the Oma facility are different from those of conventional nuclear plants.
The Oma plant will be the world’s first 100 percent MOX nuclear facility, where only mixed-oxide (MOX) fuel, consisting of plutonium and uranium, is used at reactor cores for the purpose of consuming plutonium produced in processing spent nuclear fuel.
At conventional plutonium-thermal nuclear plants, MOX fuel is used at just one-fourth to one-third of their reactor cores at most, and conventional uranium fuel is used for the remaining part.
Compared with uranium fuel, it is more difficult for control rods to suppress nuclear chain reactions of MOX fuel.
Although countermeasures, such as enhancing the capabilities of control rods and introducing larger tanks for boric acid water to better control atomic reactions, will be taken at the full MOX facility, those efforts are expected to be carefully examined during the safety screening by the NRA to check if they are sufficient.
“No full MOX facility has so far gone online around the world,” NRA Chairman Shunichi Tanaka said at a Nov. 12 news conference. “We will examine extremely carefully (if countermeasures are sufficient).”
Meanwhile, J-Power said Nov. 13 that it will also take the necessary steps to meet the stricter safety standards introduced after the Fukushima nuclear crisis.
The company said it will raise its projected earthquake preparedness scale from the current 450 gals to 650 gals. Measured with seismographs, a gal is a unit of acceleration that measures the extent of an earthquake's seismic waves. Earthquakes with high levels of magnitude also have high gal measurements.
J-Power will also have to set up the required second control room to counter possible terrorist attacks, such as ones utilizing airplanes.
J-Power estimates that the costs needed to introduce additional safety measures to comply with the new regulations will total 130 billion yen ($1.12 billion).
Elsewhere, with the Abe administration supporting the restarts of the nation's idle reactors after they pass NRA safety screenings, Kansai Electric Power Co. is making efforts to prolong the operating lives of aged reactors.
The government set the acceptable operational term of nuclear reactors at 40 years, in principle, after the Fukushima disaster, but it allows utilities to extend the period on a one-time basis by a maximum of 20 years.
Kansai Electric is currently considering applying for prolonging the operation of the No. 1 and 2 reactors of its Takahama plant in Fukui Prefecture. The two reactors began service in 1974 and 1975, respectively．
Seven reactors nationwide that will be more than 40 years old by July 2016 need to submit applications by July 2015 if the plant operators hope to extend their operational periods.
Kansai Electric is expected to apply to the government for the extension as early as next spring.
“From the beginning, we have been upgrading our facilities on the assumption that we will use the reactors for more than 60 years,” said a senior Kansai Electric official. “We hope to continue to use them if we will be able to solve safety and cost issues.”
Old nuclear power plants can recoup almost all of the costs needed to build them during their prolonged time of operations. Therefore, the longer they are operational, the more profits they are able to produce.
Because the Takahama plant No. 1 and 2 reactors have an output as large as 826 megawatts, if their lives are extended, it is estimated that Kansai Electric will save around 10 billion yen monthly by allowing it to lower its dependency on thermal power.
Although Kansai Electric is expected to spend more than 100 billion yen to introduce additional safety measures to pass the NRA screening, there remain safety concerns about prolonging the operational periods of aged reactors.
Huge costs for upgrading could also add a financial burden on reactor operators.
Kansai Electric is considering decommissioning the No. 1 and 2 reactors of its Mihama plant in Fukui Prefecture, which have turned 40 years old. Considering that the reactors have a power generation capability of 500 megawatts or less, it is difficult for them to help drastically improve the company’s financial situation.
(This article was compiled from reports by Gen Kaga, Toshio Kawada, Koji Nishimura and Tomoyoshi Otsu.)