Good news for Koeberg nuclear power station

Eskom says work on Koeberg nuclear power station’s unit two generator is progressing well, and it anticipates that it will be synchronised to the grid by the end of September 2024.

The 980MW unit was taken offline on 11 December 2023 to have its steam generator replaced. The unit one generator had the same work done between December 2022 and November 2023.

“The outage is progressing well, and the unit is projected to be back in service by the end of September 2024,” Eskom told MyBroadband.

If its prediction holds, the work done on unit two will have been completed in just under ten months — about a month quicker than unit one.

According to electricity minister Kgosientsho Ramokgopa, this is because Eskom learnt from the challenges it faced during the first unit’s steam generator replacement.

Eskom faced several delays while carrying out the maintenance on unit one, returning it to service roughly five months later than planned.

“Now we are taking out unit 2 for the same purpose. I spoke to the team and said we have learnt from the mistakes and shortcomings relating to unit 1,” Ramokgopa said in December.

“We asked them to keep to the timelines of returning unit 2.”

The successful replacement of each unit’s steam generators is critical for extending Koeberg Power Station’s operating licence, which expires in July 2024 for unit one.

“The replacement of steam generators is a huge milestone in the life of Koeberg as it was identified by Eskom as a prerequisite for the extension of the operating licence for Koeberg beyond its original design life of 40 years,” Eskom said.

“Eskom has already submitted a licence application to the National Nuclear Regulator (NNR) for Koeberg’s operating life extension by an additional 20 years, which is being assessed by the NNR.”

While the work being done at Koeberg power station is critical for the future of South Africa’s energy production, it will not be operating at full capacity for at least two years.

Combined, the two generating units contribute upwards of 1,800MW to the grid at full load.

However, in December 2023, the National Nuclear Regulator (NNR) — the organisation responsible for deciding whether extending the power station’s operating licence is safe — confirmed that the units would face further outages after the steam generator replacements.

Each will face a 200-day outage following the completion of unit 2’s steam generator replacement to assess the reactors’ concrete containment structures, which are starting to show cracks.

“For the next foreseeable years, there will be seldom both units operating at the same time,” said Peter Bester, programme manager for nuclear power stations at the NNR.

Despite the return of unit one and unit two’s work progressing smoothly, Eskom isn’t out of the woods yet.

In October 2023, managing director at EE Business Intelligence Chris Yelland said a lot could still go wrong regarding the work, putting the extension of its operating licence at risk.

Yelland said he wasn’t predicting a shutdown, merely cautioning that more delays would increase the risk of such an occurrence.