Eskom Cuts Diesel Use as Coal Fleet Performance Improves
South Africa’s state‑owned power utility, Eskom, has reported a sharp decline in its reliance on diesel‑powered backup generators as the availability of its coal‑fired fleet rises. Chief Executive Dan Marokane told Business Day that diesel consumption had “dropped dramatically” because more coal units are now online, reducing the need for costly open‑cycle gas turbines during supply stress.
Improved Generation Performance
According to Eskom’s winter 2026 outlook, the utility’s Energy Availability Factor (EAF) climbed to just over 65 % at the end of March 2025, up from less than 60 % a year earlier.[1] This improvement translates into:
- Unplanned outages averaging below 10 000 MW, compared with 12 000–13 000 MW in the same period last year.
- An average cold reserve of roughly 3 000 MW, providing a buffer against sudden demand spikes.
- A baseline assumption for unplanned outages this winter set at around 12 000 MW (down from the previous 13 000 MW).
The stronger coal fleet means Eskom can meet peak demand without firing up diesel‑driven peaking plants, which historically have been one of the utility’s most expensive tools for stabilising the grid.
Diesel Consumption and Cost Management
Marokane noted that the utility has secured enough diesel for the next two to three months at current consumption levels, but warned that fuel availability remains tied to global supply‑chain conditions.[2] He added:
“We don’t know how long this tension will last and whether it will go to the point where supply routes will be disrupted.”
By keeping diesel use low, Eskom aims to limit exposure to volatile fuel prices while maintaining operational flexibility. The utility plans to “maintain current low levels” of diesel consumption through the winter season.
Winter 2026 Outlook and Load‑Shedding Prospects
Eskom’s outlook projects around US$6.4 billion in revenue for the fiscal year ending March 2026.[3] Even under more severe scenarios—where unplanned outages could reach 14 000 MW—the utility does not anticipate load shedding, thanks to its strengthened supply capacity.
Marokane summed up the confidence:
“Between 12 000 [MW] and 14 000 [MW] … we don’t see any load shedding as our supply capacity is very strong.”
The outlook also incorporates additional industrial demand, including from ferrochrome smelters, which Eskom says has already been factored into its planning models.
Supply‑Chain Risks and Fuel Market Monitoring
Despite the reduction in diesel use, Eskom remains exposed to global fuel market fluctuations. Marokane highlighted that geopolitical pressures have contributed to diesel price volatility, although the improved fleet performance mitigates the risk.[4] The utility continues to monitor international fuel markets and logistics closely to anticipate any disruptions that could affect its backup fuel reserves.
Path to Eliminating Load Shedding
Eskom has now operated for more than 300 consecutive days without implementing load shedding—a marked improvement over previous years.[5] To build on this momentum, the utility is working with the Ministry of Electricity and Energy and other stakeholders to accelerate the phase‑out of load reduction measures.
Recent progress includes:
- The Northern Cape and Western Cape being completely removed from load‑reduction plans.
- More than 340 000 customers who previously faced load reductions now enjoying uninterrupted supply.
Eskom emphasises that sustaining this achievement will depend on maintaining generation capacity through winter demand peaks and adhering to ongoing maintenance schedules.
[1] Eskom, “Winter 2026 Outlook”, press release, March 2025.
[2] Business Day interview with Dan Marokane, March 2025.
[3] Eskom financial guidance, FY 2025/26.
[4] International Energy Agency, “Diesel Market Review”, Q1 2025.
[5] Eskom operational data, load‑shedding log, April 2023 – January 2026.
