- South Africa’s state owned energy utility, Eskom, reports that the power system remains stable, allowing for continued suspension of stage 2 loadshedding which was implemented for three days this past week.
- However existing restraints remain and approximately 2 600MW is set to return ahead of Monday evening peak.
“While stable, the system remains constrained and adequate emergency reserves are in place and strategically deployed to support demand during peak winter periods. To further stabilise the grid, 2 650MW of generation capacity is expected to be returned to service ahead of the evening peak on Monday, 19 May 2025,” said Eskom in its weekly update.
The Unplanned Capacity Loss Factor (UCLF), which measures unplanned outages, stands at 28.30% for the financial year-to-date (1 April to 15 May 2025). This reflects a slight improvement of ~0.2% compared to 28.47% recorded during the same period last year.
The financial year-to-date planned maintenance has averaged 6 669MW, representing 14.26% of total generation capacity—an increase of 3.1% compared to the previous year. As the winter season sets in, planned maintenance has been decreased, averaging 5 407MW this week (9 to 15 May)—slightly higher than the typical winter maintenance levels in prior years.
The Open-Cycle Gas Turbine (OCGT) load factor increased to 10.94% this week, compared to 3.87% in the previous week (2 to 8 May 2025).
The financial year-to-date OCGT load factor reflects a 2.8% decrease compared to the year-to-date figure from the previous week.
Diesel usage is expected to decline as more units return from long-term repairs and maintenance activities are reduced, increasing available generation capacity.
The Winter Outlook, published on 5 May 2025, covering the period ending 31 August 2025, remains valid. It indicates that loadshedding will not be necessary if unplanned outages stay below 13 000MW. If outages rise to 15 000MW, loadshedding would be limited to a maximum of 21 days out of 153 days and restricted to Stage 2.
Key Performance Highlights:
- From 9 to 15 May 2025, unplanned outages averaged 14 162MW, representing an increase of 2 490MW compared to the same period last year and 1 162MW above our base case of 13 000MW. For the financial year to date, average unplanned outages stand at 13 456MW. Fluctuations in unplanned outages were mainly driven by outage slips, which occur when a unit initially scheduled for planned maintenance is reclassified as unplanned due to exceeding the scheduled maintenance timeframe.
- As of today, unplanned outages have increased to 14 310MW, up from 11 670MW recorded last week. The available generation capacity is currently 28 548MW (excluding 720MW from Kusile Unit 6), while tonight’s peak demand is projected at 28 523MW.
- The year-to-date Energy Availability Factor (EAF) stands at 56.97%, compared to 59.98% over the same period last year. This decline is primarily due to a 3.1% increase in planned maintenance compared to the previous year and excludes 720MW from Kusile Unit 6, which is not yet in commercial operation.
- Year-to-date, Eskom spent approximately R2.85 billion on fuel for the OCGT fleet, generating 478.63GWh. This is higher than the 176.85GWh generated during the same period last year.
- The year-to-date OCGT load factor stands at 12.98%, representing a 2.8% decrease from the previous week. However, this is higher than the 4.80% recorded during the same period last year.
Author: Bryan Groenendaal
Information source: Eskom
