The strategic deployment of open-cycle gas turbine (OCGT) peaking stations has been instrumental in keeping the lights – and heaters – on this winter, says Eskom.
The power utility recently issued a statement providing an update on its winter outlook.
“Our operational efficiency continues to exceed expectations with current unplanned outages still averaging 12 000 MW and today’s (June 28), recorded at 10 839 MW, well below the winter forecast,” Eskom said.
The winter forecast, published on April 26, anticipated a likely scenario of unplanned outages of 15 500 MW and load shedding limited to Stage 2. This remains in force.
The strategic use of peaking stations, including the OCGTs, has been instrumental in meeting heightened demand, particularly during evening peaks from 17:00 to 22:00.
OCGT usage remained significantly lower than recorded in the past two years. From April 1 to June 27, expenditure on OCGTs was R3,13 billion, generating 454 GWh, approximately 66% less than 2023. The OCGT load factor for the same period was far less at 6,30% compared to last year’s figure of 21,3% over the same period.
The unplanned capacity loss factor decreased to 27% for the period, which is an improvement of 8% from 35% in the previous year.
Ongoing maintenance
Ongoing planned maintenance of 5 566 MW, bolstered by short-term maintenance to ensure continuous plant reliability, is part of Eskom’s winter strategy.
“This has resulted in a sustained improvement in the energy availability factor (EAF) for April 1 to June 27, which increased to 61,3% from 54,3% last year in the same period.” The EAF improvement is primarily due to a drop in unplanned outages of the generation units.