Oi 3 & 4 now both at full speed

July 25, 2012

Oi plant's No. 4 reactor starts capacity operation

http://mainichi.jp/english/english/newsselect/news/20120725p2g00m0dm025000c.html

FUKUI (Kyodo) -- The No. 4 reactor of Kansai Electric Power Co.'s Oi nuclear plant in Fukui Prefecture started full-capacity power generation early Wednesday to ease electricity shortages in western Japan, the operator said.

It is the second reactor to do so, following the plant's No. 3 reactor, after all of Japan's 50 commercial reactors were suspended gradually in the wake of the March 2011 nuclear disaster at Tokyo Electric Power Co.'s Fukushima Daiichi plant.

While the government has decided to restart the two reactors to ease electricity shortages, there are no prospects for any of the other 48 reactors resuming operation, leaving Japan's future electricity supply uncertain.

The government plans to inaugurate a new nuclear regulation body in September to take procedures to restart the remaining reactors.

The No. 4 reactor was reactivated on the night of July 18 for the first time in about one year, reached criticality for a self-sustaining chain reaction of nuclear fissions the following morning and began to transmit electricity Saturday.

The Oi Nos. 3 and 4 reactors' full operation is expected to nearly eliminate an estimated electricity shortage of 14.9 percent based on the peak 2010 consumption in Kansai Electric's service area including Osaka.

But the government plans to retain an electricity-saving target of 10 percent for the area set after the No. 3 reactor's start of full operation July 9, while lowering the target to around 5 percent for firms that feel affected seriously by the 10 percent restriction.

Instead, it plans to remove power-saving targets for three other utilities' service areas neighboring the Kansai Electric area. They are 4 percent power-saving targets for Chubu Electric Power Co. and Hokuriku Electric Power Co., and a 3 percent target for Chugoku Electric Power Co.

The three power companies are providing part of their electricity output to Kansai Electric to ease the supply crunch.

The government is also expected to ease the 7 percent target set for Shikoku Electric Power Co.'s service area to 5 percent.

The government plans to retain power-saving targets of 10 percent for the Kyushu Electric Power Co. area and 7 percent for the Hokkaido Electric Power Co. area due to tight electricity supply conditions there. No targets have been set for the areas served by Tokyo Electric Power and Tohoku Electric Power Co.

Since the government-requested power-saving period began July 2, electricity supply and demand conditions have been stable due to relatively low temperatures in Japan.

But utilities' electricity supply operations have been temporarily disrupted by glitches and for other reasons at some non-nuclear power plants. Furthermore, temperatures are expected to rise, raising the likelihood of increased power usage for air conditioning.

Ohi No.4 reactor working at full capacity

http://www3.nhk.or.jp/daily/english/20120725_01.html

The second reactor to resume operation in Japan after the nuclear accident in Fukushima is now generating power at full capacity.

Officials raised the output of the No.4 reactor at the Ohi nuclear plant in Fukui Prefecture, central Japan, at midnight on Tuesday after final safety checks.

The reactor reached its full capacity about one hour later on Wednesday morning. Senior vice industry minister Seishu Makino was at the plant's central control room to oversee the procedure.

The plant operator, Kansai Electric Power Company, restarted the No.4 reactor on July 18th.

Ohi's No.3 reactor resumed operation earlier this month and is running at full capacity.
The 2 reactors have the biggest output of those run by Kansai Electric, whose service area covers the country's second-largest city, Osaka.

Now that the 2 reactors are working at full swing, the government plans to lift the power-saving targets imposed on the service areas of 3 other utilities in central and western Japan.

These firms are supposed to supply electricity to Kansai Electric in the event of power shortages.

The government gave the go-ahead for Ohi's restart last month, saying its safety has been confirmed.

But a panel of experts is calling for a fresh survey of the underground cracks at the plant to check if they are active faults.