Eskom has returned Koeberg Unit 2 to service following an unplanned outage caused by a steam leak on the reheat system.
The unit was synchronised to the grid on Sunday, March 9, and has since ramped up to 646 MW. It will continue increasing its output until it reaches its full capacity of 930 MW in line with established operational protocols, Eskom says.
The restoration of Koeberg Unit 2 comes as Eskom works to stabilise the power system following Stage 3 load shedding over the weekend, which was implemented due to the loss of 2 700 MW. The unit was among those affected, experiencing a forced shutdown shortly after being brought back online earlier in the week.
“The events that triggered Stage 3 load shedding occurred while the system was already under strain,” said Eskom’s Group Executive: Generation Bheki Nxumalo.
Life extension of Unit 2
Eskom is currently refurbishing and maintaining Koeberg as part of its long-term operation (LTO) programme. The National Nuclear Regulator granted a 20-year licence extension for Koeberg Unit 1 in July last year, allowing it to continue operating until July 2044.
A similar application for Unit 2 has been submitted. The decision is expected before the current licence expires in November 2025.
“The recent LTO programme for Unit 2 included the replacement of three steam generators, extensive inspections and refuelling activities, ensuring continued safe and efficient performance. These improvements align with Eskom’s broader strategy to secure the long-term viability of Koeberg’s reactors, which are vital to South Africa’s energy security,” the utility says.
Meanwhile, Unit 1 is currently undergoing scheduled maintenance, including refuelling and statutory tests as part of the life extension process.
Summer outlook
Eskom’s summer outlook, published in August 2024, remains unchanged. Eskom acknowledged recent constraints but said “structural improvements in the generation fleet” are expected to further stabilise supply.
“We have had some delays in returning units that previously tripped back to the grid as well as in the return of three units that have been on longer-term outages. These units, bringing back 2 500 MW to the grid, will return over the coming weeks,” Nxumalo said in a media statement released on Friday (March 7) ahead of the load-shedding announcement.
“South Africa is, in no way, returning to the levels of load shedding that we experienced in 2023. While baseload capacity remains constrained, our generation recovery plan is addressing this challenge,” he said.
