South Africans should expect more blackouts during the festive season and beyond.

This is according to Eskom COO, Jan Oberholzer, who says prolonged load shedding will continue to be implemented over the coming months as major capital projects and repairs reduce available generation capacity.

Oberholzer was speaking on Tuesday at a briefing on the state of South Africa's power system. He says repairs will increase the risk of load shedding.

He says the Koeberg nuclear power station, the most reliable of Eskom's generation machines, will undergo scheduled maintenance from 8 December until June 2023.

This will remove 920MW of generation capacity from the national grid during the six months.

"Unit 1 of the Koeberg Nuclear power station, which has enjoyed 384 days of uninterrupted supply, will be shut down for normal maintenance and refuelling, and the replacement of the three steam generators as part of the long-term operation to extend its operating life," says Oberholzer.

Oberholzer says other repairs at other Kusile Unit 1, 2, and 3 and Medupi Unit 4 power stations will remove more than 2,300MW of generating capacity from the system.

"We can anticipate an increased risk of load-shedding until the repairs and maintenance are complete over the next six to 12 months," he adds.

He says this is the reality of operating a shrunken generation system bereft of any reserve margin - every single breakdown pushes the whole system to the edge.

"This loss of capacity, temporary as it is, will make for a very challenging summer this season, particularly as this is our peak planned maintenance period where a number of units at various power stations had to be shut down to conduct a much-needed maintenance," says Oberholzer.

The COO also announced the resignation of the power utility's group executive for generation, Rhulani Mathebula, with immediate effect. Mathebula took over from Phillip Dukashe who resigned in May.

South Africa has had a horror year with at least 155 days of load-shedding since January 2022 and days in the dark expected during the festive season.