The Return of Load-Shedding

After a brief respite, South Africans are once again experiencing load-shedding, a euphemism for rolling blackouts. Last week, Eskom implemented stage 2 load-shedding during peak evening hours, disrupting businesses and households alike.

The resurgence of load-shedding is attributed to a surge in unplanned outages. From May 9 to 15, 2025, unplanned outages averaged 14,162 MW, a meaningful increase of 2,490 MW compared to the same period last year. This figure exceeded Eskom’s base case scenario of 13,000 MW, the threshold beyond which load-shedding becomes necessary.

Broken Promises and Missed Targets

Eskom’s own Winter Outlook, published on may 5, 2025, had projected that load-shedding could be avoided if unplanned outages remained below 13,000 MW. The outlook further stated, If outages rise to 15,000 MW, load shedding would be limited to a maximum of 21 days out of 153 days and restricted to Stage 2.

However, the reality has fallen far short of these projections. For the financial year to date, from April 1, 2025, to May 15, 2025, average unplanned outages stand at 13,456 MW.

Eskom attributes these fluctuations to outage slips, which occur when units initially scheduled for planned maintenance are reclassified as unplanned due to extended maintenance timeframes.

The higher unplanned outages, coupled with increased planned maintenance, have caused the year-to-date energy availability factor (EAF) to plummet to 56.97%, compared to 59.98% last year. This is a far cry from Eskom’s ambitious target of reaching an EAF of 70% by March 2025, a milestone that was supposed to signal the end of load-shedding.

It will take at least two years to improve the energy availability factor from the current 58% to 70%.

Mpho Makwana, former Eskom chair, january 22, 2023

Despite repeated assurances, Eskom has failed to meet its self-imposed deadlines. in October 2024, the utility reiterated its commitment to achieving a 70% EAF by March 2025, promising a stable energy supply and reduced diesel expenditure. Eskom Chairman Mteto Nyati even declared that the Generation recovery Plan would be completed by March 31, 2025, marking the end of load-shedding.

At the end of march 2025, that’s when the plan should have been executed. At the end of that plan is when we can come back, the Minister, myself, and the CEO, and communicate to South africa that there’s not going to be load-shedding.

Mteto Nyati, Eskom Chairman, earlier this year

The latest data reveals that Eskom has missed these targets by a significant margin, leaving South Africa grappling with persistent power shortages.

Diesel Consumption Soars

Eskom’s poor performance is placing immense strain on the grid. To mitigate the impact of load-shedding, the utility is increasingly relying on its open-cycle gas turbines (OCGTs), which run on diesel, to generate electricity.

On May 16,2025,Eskom announced that it had spent approximately R2.85 billion on fuel for the OCGT fleet year-to-date, generating 478.63 GWh. This represents a staggering 171% increase in OCGT usage compared to the same period last year, when 176.85 GWh were generated through diesel generators.

This surge in diesel consumption is particularly alarming given Eskom’s earlier promises of improved performance and reduced diesel expenditure from April 2025 onwards.

The situation validates the concerns raised by former Eskom CEO Andre de Ruyter,who argued that Eskom’s performance had not improved substantially and that burning diesel was essential to keep the lights on. If the lights are on, it is because they are pouring a considerable amount of money into diesel at a rate of knots, he stated in May 2024.

FAQ: Eskom’s Load-Shedding Crisis

• Why is South Africa experiencing load-shedding? Load-shedding is due to Eskom’s inability to generate enough electricity to meet demand, primarily caused by breakdowns at power plants.
• what is the energy availability factor (EAF)? The EAF is a measure of the percentage of time that Eskom’s power plants are available to generate electricity.
• Why is Eskom burning so much diesel? Eskom is using diesel-powered generators to supplement its base load capacity and prevent more severe load-shedding.
• When will load-shedding end? Eskom has repeatedly missed its targets for ending load-shedding, and a definitive timeline remains uncertain.