Stage 4 loadshedding runs until Friday, Koeberg will soon be back online: Eskom

Koeberg nuclear power station will be fully operational again on Sunday.

This after it experienced a procedural manual trip on one of its units during the week.

Eskom said the manual trip was as a result of increasing temperature on the secondary side of the plant due to degraded heat removal (or cooling) capability- because the pump that remained in service was supplying a heat exchanger that was degraded and not able to sufficiently remove heat.

“The circulating cooling water system pump that tripped was due to low level in the suction pit as a result of the drum filter that was clogged by an acute ingress of marine life (jellyfish and fish).

“Normally, Koeberg units are able to survive a trip of one circulating cooling water system pump. The actions required from the operators are to reduce power to below 60% and to ensure that temperatures of various components on the secondary side stabilise,” said Eskom.

The power utility added that in this case, the temperature did not stabilise due to the heat exchanger remaining in service which had reduced heat transfer efficiency. 

“The excess marine life and debris have been cleared off the drum filter and it is back in service. The level in the suction pit has sufficiently recovered and the circulating water system pump has been put back in service and no anomalies have been noted.

“Upon inspection, it was found that the pump had not been damaged as initially feared,” it said.

The current projected synchronisation date is Sunday, March 15 2020.

Eskom advised that stage 4 load-shedding will continue until Friday evening.