Eskom breakdowns milestone
Eskom reports that, on Friday, its power station breakdowns were at their lowest levels recorded in nine months.
“As of 1 August 2025, unplanned outages stand at 8,525MW, the lowest level in recent history, narrowly surpassing the 8,258MW recorded on 28 October 2024,” Eskom stated.
“The generation fleet continues to show ongoing solid momentum, with over half (57%) of Eskom’s fourteen coal-fired power stations now operating at an energy availability factor (EAF) above 70%.”
Eskom said three power stations had achieved a notable performance of more than 90% EAF. “An additional four stations are operating above 60%, reflecting the fleet’s growing stability and improved reliability,” it said.
EAF measures the generating capacity available from Eskom power plants relative to their installed capacity. It takes breakdowns and maintenance into account.
Eskom said the average breakdowns at its power stations this week were 10,206MW, well below the threshold at which it would need to implement load-shedding according to its winter forecast.
For the first time in many weeks, breakdowns were also lower than the same period last year (10,229MW).
The state-owned power utility also reported a substantial decrease in open-cycle gas turbine (OCGT) usage for the week of 25–31 July 2025 and an improvement in its energy availability factor.
This is the second consecutive week that Eskom’s weekly average breakdowns have been below the 13,000MW level, the threshold above which load-shedding becomes a probability.
“With 30 days of Eskom’s winter outlook period still remaining, the system remains well-positioned to maintain stability and meet demand effectively,” Eskom said.
“When occasional system constraints arise, they are effectively managed through the strategic deployment of emergency reserves during morning and evening peak periods.”
Eskom said its winter outlook, published on 5 May 2025, remains valid. If outages rose to 15,000MW, stage 2 load-shedding would be probable, albeit limited to a maximum of 21 days out of 153 days.
Load-shedding has thus far remained well below these levels, despite breakdowns hovering in Eskom’s “danger zone” for ten consecutive weeks.
Eskom said there has been no load-shedding since 15 May 2025, with only 26 hours recorded between 1 April and 24 July 2025.
“To further strengthen grid stability, Eskom is planning to return a total of 3,075MW of generation capacity to service ahead of the evening peak on Monday, 4 August 2025, and throughout the coming week,” it stated.
As winter started, Eskom reduced the amount of scheduled maintenance conducted on power plants to ensure sufficient capacity to meet demand.
During the week, planned maintenance decreased to an average of 4,745MW. Its weekly energy availability factor (EAF) ranged from 64% to 71%, with the month-to-date average EAF increasing to 64.08%.
The Unplanned Capability Loss Factor (UCLF), which measures the capacity lost due to breakdowns, decreased to 28.58% for the financial year to date. This was higher than the 26.60% UCLF during the same period last year.
Eskom diesel usage
Another measure indicating substantial improvements at Eskom was that it reported a further decrease in its weekly OCGT load factor from 1.86% to 0.31%. “This indicates less reliance on OCGTs,” Eskom said.
Open-cycle gas turbines (OCGTs) are diesel-powered stations that Eskom uses to help balance the grid and as emergency generation units to keep load-shedding at bay.
The year-to-date load factor for OCGTs decreased to 9.55%. This figure remains higher than the 4.93% recorded during the same period last year.
“From 1 April to 31 July 2025, diesel spend remains within the budget allocated,” Eskom said. The power utility spent an additional R10 million on diesel during the past week.
Year-to-date, Eskom spent R5.626 billion on fuel for the OCGT fleet, generating 954.20GWh of electricity. This output is still higher than the 493.17GWh generated during the same timeframe last year.
Eskom reported that its year-to-date EAF has increased to 59.88% and remains lower than the 62.84% recorded during the same period last year, primarily due to a 2.3% increase in breakdowns.
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