Dark days ahead for South Africa

Energy analyst Chris Yelland says South Africa must aggressively roll out renewable energy, battery storage, and gas-to-power plants.

This is because Eskom’s existing generation fleet remains unreliable, and because the state-owned electricity utility’s older power plants must soon be taken offline as they do not comply with environmental standards.

Yelland said that even newer power plants and Eskom’s nuclear power station, Koeberg, which is supposed to be incredibly reliable, have proven intermittent.

Koeberg Unit 2 experienced what Eskom called a “non-technical trip” at the beginning of March, immediately costing the power utility 930MW of generating capacity.

Days later, it brought Koeberg back online only for it to trip again, once again plunging South Africa into load-shedding.

On Monday, 10 March, Eskom announced that it successfully returned the unit to service the day before. It remains to be seen whether it will remain online.

Eskom also revealed that a steam leak on the reheat system caused the unplanned outage.

“A nuclear power station is often touted as a 24-hour, reliable, baseload, dispatchable power generator,” Yelland said.

“This switching on and off of units at Koeberg has been going on for the last three years, as Eskom has been doing the life extension — the so-called Long-Term Operation upgrade.”

Yelland said Koeberg was now over 40 years old, and Eskom needed to extend its life for a further 20 years, which has resulted in what can only be described as a highly intermittent power station.

“For the last several years, Koeberg cannot be described as 24-hour, baseload, reliable supply.”

“The Koeberg nuclear power generator units are is demonstrably and objectively intermittent,” said Yelland.

Eskom’s largest and newest coal-fired power plants, Medupi and Kusile, have also been experiencing breakdowns.

In addition to Eskom’s largest power generators being unreliable, Yelland warned that by 2030, numerous coal-fired power plants in Eskom’s fleet will have to be decommissioned and taken off the grid.

Eskom violating air quality standards

Yelland explained that many Eskom power stations do not comply with South Africa’s air quality regulations.

“The Minister of Forestry, Fisheries, and the Environment said they do not intend to extend the moratorium Eskom enjoys with compliance with the law,” he said.

“The only reason these power plants continue operating is because they continue getting extensions on their licences without having to comply with the law.”

Yelland said this was unsustainable and that the Minister of Forestry, Fisheries, and the Environment said it could not continue.

He said the problem with the situation is that Eskom is holding South Africa to ransom with the threat of load-shedding.

“Eskom says, if you want us to keep these power plants going, you either give us an exemption from the law or we will switch them off,” said Yelland.

There is not much of a choice because shutting down the power stations without replacing them will plunge the country into severe load-shedding.

Yelland said the solution is aggressively installing new renewable energy, battery storage, and gas-to-power plants.

“These are the only power generation solutions that can be delivered in the short term in South Africa,” he argued.

Stage 5 load-shedding warning

Over the last few weeks, Eskom unexpectedly announced stage 3 and stage 6 load-shedding.

On Friday, 7 March 2025, the state-owned power utility once again implemented Stage 3 load-shedding at short notice after losing 2,700MW of generation capacity from the grid.

Eskom said the constrained capacity resulted in the increased reliance on emergency reserves during the week.

This made it necessary to focus on replenishing these critical resources during the weekend in preparation for the business week.

Eskom explained that the problems included two Kusile units whose coal operations went sub-optimal following adverse weather in the area.

Yelland said this was “Eskom speak” for their failure to handle rainy periods through proper coal operations at its power plants.

“What Eskom really means is that the problem is wet coal. It is an old excuse,” he said.

He explained that the issue related to coal fines at the bottom of a stockpile that turns to mud when there are heavy rains.

“This mud or slush is difficult to handle, and it causes blockages on conveyers and conveyer shoots.”

Yelland said there were ways to mitigate this problem, including prober drainage, covering the stockpiles, and ensuring they are packed with good coal.

Despite the latest load-shedding and challenges with wet coal, Eskom’s group executive of generation, Bheki Nxumalo, remains upbeat.

He said they are committed to ensuring that South Africa will not return to the levels of load-shedding it experienced in 2023. 

Nxumalo said Eskom’s ongoing generation recovery plan will bring an end to load-shedding in South Africa.

However, energy expert Sampson Mamphweli from Sanedi said that in winter, South Africa’s electricity demand will once again rise, putting pressure on the grid.

Unless Eskom can return all the generation units it took offline for maintenance in time for the winter peak, South Africa can face dark days.

“If these units are not returned to service on time, South Africans should brace themselves for Stage 4 and Stage 5 load-shedding,” he said.