No. 2 N-pool cooling system restored
A cooling system for the water in a temporary storage pool for spent nuclear fuel rods has been fully restored at the Fukushima No. 1 nuclear power plant, Tokyo Electric Power Co. has announced—the first such achievement since the March 11 disaster and months ahead of schedule.
According to TEPCO, the cooling system was restored Tuesday for the storage pool at the No. 2 reactor building of the Fukushima plant. This represents the first full, stable recovery of a cooling system at the plant since it suffered extensive damage in the March 11 earthquake and tsunami.
Tuesday’s recovery also was far ahead of the January deadline TEPCO set in its timetable for bringing the crisis at the plant under control.
It cools a pipe that run from the temporary storage pool into a heat exchanger, using the cooling water in the exchanger. The water from the heat exchanger is cooled with air from a fan.
The temperature of the water in the storage pool is currently 70 C to 80 C. As water in the pool is lost through vaporization, additional water is poured into the pool to compensate.
If the cooling system works efficiently, the temperature will be stabilized at around 40 C, according to TEPCO.
The humidity in the No. 2 reactor building has been as high as 99 percent, due to steam from the fuel pool and other factors.
If the humidity goes down, much more efficient work will be possible in the building.
A similar system will be put into operation for the Nos. 1 and 3 reactor buildings by the end of this month and at the No. 4 reactor building in July, according to TEPCO.
The Yomiuri Shimbun , Jun 2, 2011
http://www.yomiuri.co.jp/dy/national/T110601005305.htm
Tohoku Electric may tap Tepco for power shortchanging
SENDAI – Tohoku Electric Power Co. may seek compensation from Tokyo Electric Power Co. over its failure to meet a power supply contract following the March quake and tsunami, sources said.
Under a contract between the two utilities, Tepco agreed to supply Tohoku Electric with electricity from its Fukushima No. 2 nuclear plant, located 15 km from the leaking Fukushima No. 1 station.
Tohoku Electric contributed 25 percent of the funds used to build reactors 3 and 4 at the Fukushima No. 2 plant and is entitled to receive the same percentage of electricity generated by them. But Tepco has failed to deliver on the contract due to damage to the plant from the disaster, the sources said.
The Fukushima No. 2 power station has been put into a cold shutdown despite temporarily experiencing a partial loss of cooling functions after suffering damage in the disaster.
Tohoku Electric is hoping to start negotiations with Tepco when the prospects for bringing the nuclear crisis at the Fukushima No. 1 plant under control become clear, the sources said.
Tohoku Electric could demand compensation worth tens of billions of yen if reactors 3 and 4 at the No. 2 plant are decommissioned, the sources said.
In fiscal 2010, which ended in March, Tohoku Electric fell deep into the red, logging an extraordinary loss of \109.3 billion in connection with the suspended operation at its Onagawa nuclear power plant in Ishinomaki, Miyagi Prefecture, and other facilities damaged by the disaster.
The company may fail to meet electricity demand this summer unless it buys power from other suppliers.
Kyodo, June 2, 2011
http://search.japantimes.co.jp/cgi-bin/nn20110602a4.html