Good news about winter load-shedding

Energy expert Chris Yelland believes Eskom is well prepared to avoid load-shedding or minimise the power cuts during the coming winter.

The EE Business Intelligence managing director recently posted his latest analysis of Eskom’s system status outlook for Week 16 of 2025. 

Yelland said that although Eskom’s energy availability factor (EAF) remained stubbornly low at roughly 57%, this was not the whole picture.

He explained that the low EAF was impacted by Eskom increasing its planned maintenance to the highest levels yet since 2022. 

“Planned maintenance outages have risen very significantly for the last six weeks to the highest levels in three years at this time of year, “Yelland said.

In addition, breakdowns have also reduced, which means Eskom is less exposed to sudden changes in generation availability.

“Unplanned outages — such as generator breakdowns and partial load losses — have also dropped to 26% over the last three weeks,” Yelland said.

The latest performance is a significant improvement from a few weeks ago, when load-shedding looked highly likely.

Yelland argued that this improved performance and several large power station units “hopefully” coming online soon put Eskom in a good spot for June, July, and August. 

He provided the following estimated timeline for the units to begin feeding power into the grid:

• 800MW Medupi Unit 4 return to service after explosion repairs  — End of April or mid-May 2025
• 800MW Kusile Unit 1 return to service after transfer to flue-gas desulphurisation system — End of June 2025
• 900MW Koeberg Unit 1 return to service after long-term refurbishment and refuelling — September 2025
• Kusile Unit 6 reaching full commercial operation — October 2025 

These large units will add a combined 3,300MW to the grid, equivalent to the demand shaved through three load-shedding stages.

The graphs below compare Eskom’s EAF, unplanned capacity load factor (UCLF), and planned capacity load factor (PCLF) in 2025 with previous years.

Big performance swing

Earlier in April, Yelland and several other experts and industry stakeholders expressed concerns about high levels of unplanned outages and increased reliance on emergency generation. 

On 3 April 2025, Eskom’s unplanned capacity load factor was around 30%, which Yelland said was less than ideal.

Roughly a week later, Yelland said he expected some “intermittent” load-shedding over the next six months as the trends remained similar.

The Centre for Risk Analysis (CRA) and the Minerals Council South Africa had similar warnings.

The CRA warned unless Eskom could reverse the unplanned outage trend, there would be a substantially increased risk of load-shedding during the winter.

The latter was particularly concerned about Eskom’s increased use of open-cycle gas turbines (OCGTs) in March 2025, which was significantly higher than in the previous three months and March 2024.

Eskom itself has not yet raised any concerns over unplanned outage trends and OCGT usage.

In its most recent generation recovery plan update, the power utility said its UCLF stood at 27.48% between 1 and 17 April 2025, a 2.7 percentage point improvement over the same period last year.

Eskom also said that its stagnant EAF was mainly due to higher planned maintenance.

The PCLF stood at 15.41% of generation capacity, marking a 3.8 percentage point increase compared to the same period last year.

“The high level of planned maintenance aims to enhance fleet reliability for the anticipated increased peak winter demand while ensuring compliance with environmental and regulatory requirements,” Eskom said.

Eskom is expected to give its official forecast for the winter load-shedding period during a media briefing next week.