Eskom load shedding warning

Eskom said that it could avoid load shedding this winter if it kept breakdowns below 13,000MW, but new data shows that South Africa has exceeded this for the past two months, and continues to do so.

This means that the country is walking a fine edge, with experts warning that load shedding could hit at very short notice.

In it latest power alert, Eskom noted that unplanned outages averaged 14,644MW from 30 May to 5 June 2025, representing an increase of 2,315MW compared to the same period last year.

Worryingly, this is 1,644MW above Eskom’s base case of 13,000MW in unplanned outages for winter.

Delivering its winter outlook for 2025, Eskom said its base case for the winter period was no load shedding.

However, it warned that, should demand exceed the expected outage limit of 13,000MW, the country could experience 21 days of stage 2 load shedding in the “worst-case” scenario.

Despite the worst case not being the ‘expected’ case, operational failures at Eskom in the first few months of the year showed that circumstances can change quickly and load shedding can kick in with little warning.

Between January and April, South Africa experienced five ’rounds’ of load shedding, which typically followed the loss of multiple units across key power stations.

Notably, this was counter to Eskom’s summer outlook, which anticipated no load shedding over the period, and stage 1 load shedding at worst.

Instead, the country saw 14 days of load shedding between stage 2 and stage 6. Similarly, Eskom’s winter plan of no load shedding has already fallen flat.

Load shedding hit in May for three days—from 13 to 15 May—which was contained to a total of 18 hours of outages at stage 2 during evening peaks.

The latest Electricity Update from the Minerals Council South Africa (MCSA) tells a more positive story.

The group noted that Open-Cycle Gas Turbine (OCGT) usage declined during the month, and planned maintenance was cut by over 1,500MW, contributing to an improvement in energy availability (EAF).

EAF improved in May, rising by nearly three percentage points to 59.3%, as maintenance downtime was cut.

“This is in line with the normal seasonal pattern where Eskom reduces planned maintenance in the colder winter months when residential electricity demand is higher,” said MCSA chief economist André Lourens.

However, Lourens pointed out that unplanned outages (breakdowns), while remaining relatively stable, averaged around 13,500 MW on average in May, and around 15,223 MW in April. 

Eskom said that for the financial year to date, average unplanned outages stand at 13,760MW.

“The increase in unplanned outages is largely driven by outage slips,” it said.

A very fine line

Worryingly, this is above Eskom’s 13,000 MW threshold, which is needed to avoid all load shedding stages in winter.

The MCSA also flagged that both planned and unplanned outages remained elevated compared to 2024, despite the improved EAF.

Regardless, Lourens noted that May 2025 reflected a “modest but encouraging” improvement in South Africa’s electricity supply performance. 

The uptick in EAF to 59.3% was supported by reduced planned maintenance and lower reliance on costly OCGTs.

“This suggests that Eskom is gaining some traction in its Generation Recovery Plan, and comes at a critical time, with winter demand pressures mounting,” he said. 

However, he warned that the underlying fragility of the system remains.

“Load shedding was contained to three days in May, but the fact that it re-emerged, even if limited, serves as a reminder of ongoing generation constraints.” 

The fact that breakdowns are exceeding the 13,000MW target set by Eskom is also worrying, he said.

Eskom has admitted that the grid remains strained but stable. According to the utility’s latest 52-week outlook, load shedding remains a risk in the weeks to come.

The generation adequacy report shows that the greatest risk of a 2,001MW shortfall in meeting demand lies between 16 June to 20 July.

While not exact, losing more than 2,000MW of generating capacity would necessitate at least Stage 2 load shedding, aligning with Eskom’s Winter Outlook for 2025. 

Despite the pressure on the national grid, Eskom insists that it is stable for now.