Nuclear power station maintenance under way

30th April 2021

In the recent system status and outlook briefing by State-owned power utility Eskom that took place on March 15, 2021, details of the refuelling and maintenance outage of the Koeberg nuclear power station were provided.

The maintenance outage of Unit 1, which is currently in progress, started on January 3 this year. The outage started five weeks earlier than planned with the forced shutdown caused by a steam generator tube leak.

After the fuel was unloaded from the reactor, the steam generator leak location was identified and the unit is planned to return to service in May. The outage caused no nuclear safety risk.

The unplanned shutdown of Koeberg Unit 1, as well as the delayed return to service of some units after the December maintenance period, have necessitated the maintenance schedule be revised in February for the 18-month maintenance period that lies ahead.

Koeberg Unit 2 is operating at full power and has been for 142 days since its previous refuelling and maintenance outage, which was completed October 21, 2020.

Additionally, the first three steam generators have been delivered to Koeberg and the first steam generator replacement is planned for the next Unit 2 outage in January 2022.

The September and November 2020 earthquakes in the Western Cape area, which measured 2.7 and 3.5 on the Richter scale respectively, had no impact on the plant. The Koeberg plant is designed to withstand a Richter scale earthquake of up to 7.0 and further improvements on the plant have increased its resilience to major events.

Koeberg’s containment buildings remain fully effective to withstand even the most severe possible accident as shown by in-service testing and analysis – the maintenance, testing and inspection programmes will continue to manage the containment health for the remainder of the plant life of the plant.