Struggling utilities now down to 2 reactors online

February 21, 2012

Electric power companies are warning of impending blackouts while eagerly awaiting approval of “stress test” reports to restart their reactors. But they also have to win over local governments and are now facing growing calls for further safety tests that would all but ensure Japan would be without nuclear energy this summer.

The No. 3 reactor at the Takahama nuclear power plant in Fukui Prefecture, the last nuclear reactor operational in western Japan, went offline for a regular inspection at 11 p.m. on Feb. 20. Osaka-based Kansai Electric Power Co. operates the plant, which has an output capacity of 870 megawatts.

The only two reactors still operational in Japan are both located in eastern Japan. One of them, the No. 6 reactor at the Kashiwazaki-Kariwa nuclear plant of Tokyo Electric Power Co., will go offline on March 26, while the other, the No. 3 reactor at the Tomari nuclear plant of Hokkaido Electric Power Co., will be shut down in late April.

If no nuclear reactor is restarted by that time, none of Japan's 54 nuclear reactors will be operational.

The government has projected a 7-percent power shortage at peak demand during the summer in Japan if all nuclear reactors remain offline and if the heat is as intense as in 2010.

"It is essential to restart nuclear power to ensure a stable supply of power," Kansai Electric President Makoto Yagi told a news conference on Feb. 20.

The government is proceeding with steps to restart reactors at Kansai Electric's Oi nuclear plant in Fukui Prefecture. One key will be winning the approval of local communities, which is far from guaranteed in light of growing anti-nuclear sentiment following the accident at the Fukushima No. 1 nuclear plant.

The central government, seeking to ensure safety and alleviate public concerns, required all reactors to undergo stress tests before they can be restarted. The stress tests evaluate the extent of emergency safety measures taken following the Fukushima accident.

So far, eight utilities have submitted "primary assessments" on 16 nuclear reactors to the Nuclear and Industrial Safety Agency. Screening of the reports is under way.

Some of the earliest reports were filed for the No. 3 and No. 4 reactors of the Oi nuclear plant. NISA on Feb. 13 described these reports as "appropriate," and submitted its assessment to the Nuclear Safety Commission of Japan.

Once the NSC has evaluated NISA’s report, relevant Cabinet members are expected to make a political decision on whether the reactors may be restarted.

But there have also been calls for "secondary assessments" aimed at uncovering reactor weaknesses in more detail and seeking methods on improving them.

Although the government said the deadline was at the end of last year, no utility has submitted a "secondary assessment" report so far.

"The primary assessments alone are not sufficient to evaluate the safety," NSC Chairman Haruki Madarame told a news conference on Feb. 20. "I want to see secondary assessments conducted in full."

The International Atomic Energy Agency has also said NISA should ensure that secondary assessments are implemented.

"It is up to the government to link the primary assessment results to whether operation can be restarted," Madarame said. "It is not up to the NSC to make that decision."

NISA’s stress tests are based largely on similar tests in the European Union. But the tests in Europe have been criticized as too narrow in scope.

In October, a group of European Parliament political parties critical of nuclear power compiled a report to point out the shortcomings of the stress tests. The report argued that consideration of earthquakes and floods alone was insufficient, and that accident scenarios should also include airplane crashes, internal fires, human error or any combination thereof.

Like the European stress tests, the primary and secondary assessments in Japan do not cover fires, human error or terrorist attacks.

In addition, the government of Fukui Prefecture, which hosts the Oi nuclear plant, has said the stress tests were insufficient to warrant a restart of reactors. The prefecture said authorities should also come up with provisional safety standards based on lessons learned from the Fukushima No. 1 nuclear plant accident.

NISA on Feb. 20 presented 30 safety measures to the Fukui prefectural government, including the installation of multiple emergency power generating systems and enhanced operability of equipment to lower internal pressure within nuclear reactors. NISA, however, has yet to compile a clear plan on how to implement these measures.

Concrete safety standards are expected to be drawn up only after a new nuclear regulatory agency is created in spring by merging NISA and the NSC.

Chief Cabinet Secretary Osamu Fujimura, in a news conference on Feb. 20, indicated that local approval and public understanding would outweigh possible power outages in decisions concerning the resumption of nuclear reactor operations.

"Whether nuclear reactors can be restarted is a separate issue from the supply and demand of power," Fujimura said. "We will make decisions by considering whether we have obtained the understanding of local communities and the trust of the general public."

  • 1
submit to reddit
The Asahi Shimbun

The Asahi Shimbun

  • The Asahi Shimbun
  • The No. 3 reactor, left, of the Takahama nuclear power plant in Takahama, Fukui Prefecture, awaits shutdown for regular inspection on the evening of Feb. 20. The No. 4 reactor, right, is already offline. (Shigetaka Kodama)

More AJW