During a panel discussion at the Enlit Africa 2023 conference in Cape Town on Tuesday, May 16, 2023, acting Eskom CEO Calib Cassim expressed that it would be considered a success if the utility could prevent load-shedding from exceeding stage 6 in the upcoming winter. Cassim acknowledged that Eskom’s generating team had assessed various scenarios for load-shedding but highlighted that the utility was starting the winter season at a disadvantage as reported by My Broad Band.
He stated, “It is going to be a tough winter,” mentioning that three units at Kusile were operational during the previous winter but were no longer available this year, resulting in a loss of 2,000MW of capacity. These units were offline due to the collapse of a flue-gas desulphurisation duct in October 2022 and are expected to return to service by the end of the year, provided Eskom is granted exemptions from certain emissions limits.
Additionally, Cassim noted that during last year’s winter, both units at the Koeberg nuclear power station were operational, providing 1,860MW of capacity at peak. However, only Unit 2 will be available this year, as Unit 1 is scheduled to be offline until next year for a life extension project, further reducing capacity by 970MW.
Eskom will have approximately 3,000MW less capacity, equivalent to three full stages of load-shedding, without considering any unplanned breakdowns. Cassim explained that the best-case scenario for Eskom’s winter outlook would involve managing load-shedding between stage 4 and stage 6. He stated, “If we can keep the peak load-shedding at stage 6 or lower and off-peak load-shedding at stage 4, I think we are going to have a successful winter.”
However, if the availability of the remaining units during the winter period is similar to last year, load-shedding could exceed stage 6. This is because Eskom implemented stage 6 load-shedding, the highest level, during winter last year.
With an additional 3,000MW of unavailable capacity, Eskom may be compelled to implement stage 9 load-shedding during peak periods and stage 7 during off-peak periods. The only alternatives to avoid this scenario are a significant reduction in demand or substantial improvements in the performance of other power stations, according to University of Johannesburg physics professor Hartmut Winkler and energy expert Clyde Mallinson.
Eskom’s System Operator, responsible for maintaining supply-demand balance and preventing grid collapse, recently updated the load-shedding code of practice to include guidance for municipalities on implementing stage 9 to stage 16 load-shedding. Winkler indicated that under stage 9 load-shedding, South Africans should anticipate 12 hours without power each day, alternating between four hours with electricity and four hours without.
Eskom issued a statement countering claims of an imminent grid collapse circulating on social media, asserting that the risk of a national blackout is highly unlikely. Cassim echoed this sentiment, expressing confidence in the System Operator staff’s work and emphasising that he is not currently concerned about a blackout but rather about the potential need for stage 8 load-shedding.
Photo: Facebook / @Eskom Hld SOC Ltd