'Pluthermal' trial finally starts

GENKAI, Saga Prefecture--Despite lingering questions about safety, cost efficiency and waste disposal, the trial operation of the long-delayed "pluthermal" program--perhaps the future of Japan's energy needs--started here Thursday.

Kyushu Electric Power Co. began using plutonium-uranium mixed oxide (MOX) fuel at the No. 3 reactor of the Genkai Nuclear Power Station at 11 a.m., when engineers started removing the control rods from the core.

The fuel was expected to reach criticality Thursday night, officials of the power company said. The company will gradually generate electricity from Monday and start Japan's first pluthermal power generation on a commercial basis on Dec. 2.

Initially, power generation will be 30 percent of the reactor's total capacity. The percentage will increase in four stages until it reaches maximum output by the middle of this month, the company said.

In the pluthermal program, plutonium is extracted from spent nuclear fuel, mixed with uranium and reused to generate power.

The program is a pillar of Japan's national policy of creating a "nuclear fuel cycle."

The MOX fuel for the plant was brought to Japan in May from France, which reprocessed spent nuclear fuel from the Genkai plant and the Sendai Nuclear Power Station in Kagoshima Prefecture, also operated by Kyushu Electric Power.

In mid-October, the MOX fuel was put into the No. 3 reactor's core.

The government focused more attention on the pluthermal project after problems inundated plans to use fast-breeder reactors.

But MOX fuel costs more than conventional uranium fuel in terms of production and transportation. And the pluthermal program can reduce the amount of uranium used by only 10 to 20 percent.

Disposal methods of nuclear waste produced in the program are still not clear. And there is also the issue of safety in the operations.

Although the Genkai town and Saga prefectural governments approved the pluthermal project, local residents are opposed, citing concerns about the use of plutonium.

The pluthermal program is also scheduled to start at the Ikata Nuclear Power Station in Ehime Prefecture by Shikoku Electric Power Co. in February, and in the Hamaoka Nuclear Power Station in Shizuoka Prefecture by Chubu Electric Power Co. around summer next year.

Kansai Electric Power Co. plans to put MOX fuel in a reactor at the Takahama Nuclear Power Station in Fukui Prefecture by the end of March 2011.

Chugoku Electric Power Co. plans to start the pluthermal program at its Shimane Nuclear Power Station in Matsue in fiscal 2014.

Thursday's start of the trial operation is 10 years later than planned.

Plutonium, which is produced in the nuclear fuel cycle, was initially supposed to have been used in fast-breeder reactors. These reactors are called "dreamlike nuclear reactors" because they generate more plutonium from the spent nuclear fuel than the amount originally consumed.

However, operations of the Monju prototype fast-breeder reactor in Tsuruga, Fukui Prefecture, have been suspended for the past 14 years due to an accident. The expected year in which the fast-breeder reactors can be put into practical use is now 2050.

Because of the delay, the pluthermal program, which had been regarded as a stopgap measure, was promoted as the main system in 1997.

The program, approved at a Cabinet meeting in 1997, was scheduled to start at three or four reactors by 2000, with the number jumping to 16 to 18 by around 2010.

However, Kansai Electric Power froze the pluthermal plan after data on MOX fuel was found in 1999 to have been fabricated during the manufacturing processes in Britain.

Tokyo Electric Power Co. followed suit after cover-ups of problems at its nuclear plants were exposed in 2002.(IHT/Asahi: November 6,2009)