A minor glitch occurred at the newly restarted No. 1 reactor of the Sendai nuclear power plant in Kagoshima Prefecture, Kyushu Electric Power Co. said on Aug. 21.
A minor glitch occurred at the newly restarted No. 1 reactor of the Sendai nuclear power plant in Kagoshima Prefecture, Kyushu Electric Power Co. said on Aug. 21.
The malfunction forced the postponement of work for raising the output of the reactor, the utility said.
According to the plant operator, a tiny amount of seawater leaked into a condenser in the secondary cooling system of the reactor, which has an output of 890 megawatts, it said.
The utility said at 2:19 p.m. on Aug. 20, an alarm sounded to warn of an abnormality in the water flowing in the condenser, a device that converts steam used in power generation to water by cooling it.
After checking the equipment, Kyushu Electric said an extremely small amount of seawater mixed into the water flowing in the condenser.
The seawater normally flows in a narrow titanium tube adjacent to the condenser to help cool steam in the condenser unit. The utility suspects that a tiny hole in the titanium tube caused the seawater to leak.
Kyushu Electric said the seawater was removed with a desalination device and operations at the No. 1 reactor were not hindered. The utility will continue to operate the reactor to generate and transmit electricity.
The output of the No. 1 reactor was scheduled to be raised from 75 percent to 95 percent on Aug. 21. However, the output will be maintained at 75 percent so the utility can investigate the cause of the seawater leak in detail. The work will take about a week.
Likewise, full operations of the reactor that were scheduled to be made on Aug. 25 are also likely to be pushed back, Kyushu Electric said.
The No. 1 reactor at the Sendai plant in Satsuma-Sendai is the first reactor in Japan to be brought back online under new safety regulations imposed by the Nuclear Regulation Authority.