Energy analyst Chris Yelland warned that the increased risk of Koeberg shutting down means the Western Cape is more vulnerable to a total power blackout.

Yelland explained that the risk of both nuclear reactors at Eskom’s Koeberg Nuclear Power Station being shut down simultaneously for life extension continues to increase.

Eskom said there would be a further delay in the return to commercial operation of the 970 MW Unit 1 at Koeberg, which is undergoing life-extension work.

It has previously extended the expected date for the return to service of Unit 1 several times from the initial indicated completion date of mid-June 2023.

Unit 1 at Koeberg is now expected to be synchronised to the grid by 30 October 2023 and to return to commercial operation at full output by 13 November 2023.

The shutdown of the 970 MW Unit 2 at Koeberg will, therefore, also be delayed, if necessary, until after the commissioning of Unit 1 is complete.

Unit 2 will be shut down for refuelling, maintenance, and replacement of its three steam generators in a similar operation to the 11-month outage of Unit 1.

After the return to service, Unit 1 is scheduled for a further 200-day shutdown commencing on 21 July 2024.

This is the same day that Koeberg’s current National Nuclear Regulator (NNR) operating licence expires.

This would appear to indicate that the NNR may not be able to grant an extension of Koeberg’s operating licence when it expires on 21 July 2024.

Eskom has applied for separate expiry dates in the Koeberg licence for Unit 1 and Unit 2 because Unit 2 was commissioned about 18 months after Unit 1. Eskom is still awaiting a decision from the NNR.

If the NNR does not grant this license, Unit 1 and Unit 2 may have to shut down on 21 July 2024.

Yelland explained that Eskom’s Koeberg is essential for grid stability in the Western Cape.

Without Koeberg, the Western Cape has to import a lot of power from the north of South Africa via transmission lines.

While it is possible, the province becomes more vulnerable. When a transmission line trips, which has happened, it can leave the Western Cape vulnerable to a blackout.

“The less generation capacity there is in the Western Cape, the more vulnerable it is to a regional blackout,” Yelland said.