Eskom officials on Thursday, warned that Stage 8 rolling blackouts could occur during the winter months if interventions to reduce demand and improve reliability are ineffective. 

Read in Daily Maverick: Brace yourself for a long, cold, dark winter as SA teeters on the edge of Stage 7/8 rolling blackouts

The power utility presented its winter outlook during a state of the system briefing on Thursday morning. The key takeaways from the briefing confirmed media reports over the past weeks that South Africa would be teetering on the edge of Stage 7 and 8 rolling backouts during the winter months.

Eskom is heading into the winter season on the backfoot, with 3,080 MW of generation capacity less than it had the previous year, said Eskom interim chief executive, Calib Cassim. The load losses are associated with a flue gas duct incident at Kusile power station and delays in returning one unit to service at Koeberg power station, he said. 

The unit at Koeberg is expected to return to service in September 2023. 

Eskom has 47,512 MW of installed capacity, but only 26,512 MW of available capacity — against a demand of 33,000 MW. 

Cassim said Eskom’s key objective this winter season is to keep its unplanned capability loss factor (UCLF) – or unplanned losses – at less than 15,000 MW. “However, we know it’s been a struggle to keep it at this level,” he said. 

Eskom’s UCLF for the financial year (which began on 1 April) to date, according to Eskom head of generation Bheki Nxumalo, has averaged between 16,000 MW and 17,000 MW. 

“If the UCLF — unplanned outages — reaches levels of 18,000 MW, then the likelihood of Stage 8 load shedding during peaks is extremely high,” said Cassim. 

Read more in Daily Maverick:  Readers reveal their load shedding realities

Stage 8 blackouts, Cassim explained, would mean 16 hours of interrupted supply in a 32-hour cycle. 

Eskom head of transmission, Segomoco Scheppers said that the power utility has considered three scenarios for the winter season: 

• Base case: Eskom assumes unplanned outages of about 15,000 MW, which would require rolling blackout to be implemented between Stage 3 and Stage 5 on most days, from May to 31 August.
• Second scenario: Eskom assumes unplanned outages of about 16,500 MW, which would mean Stage 6 rolling blackouts every day, from May to 31 August.
• Worst case scenario: Eskom assumes unplanned outages of 18,000 MW, meaning Stage 7 rolling blackouts would be implemented for every day in May and June, and Stage 8 rolling blackouts for every day in July and August.

“If unplanned outages average 18,000 MW for the winter period, load shedding will be required every day, and will be implemented up to Stage 8,” read Scheppers’ presentation. 

Scheppers reiterated that the winter outlook is “tight” and that any significant outages slips, such as delays in returning units to service, would have a knock-on effect that would influence the plan from that point forward. 

Importantly, he said the winter outlook does not cater for challenges that “could arise at power stations due to industrial action or other protests.”

Slow-moving vehicles line the streets as traffic lights stand without power during a rolling blackout period in Pretoria, South Africa, on Wednesday, 13 February, 2019. (Photo: Waldo Swiegers/Bloomberg via Getty Images)

Energy availability factor 

Eskom board chairperson, Mpho Makwana said the board was committed to meeting the targets for an energy availability factor (EAF) of 65% by the end of March 2024, and the “penultimate goal” of 70% EAF, by 31 March 2025.

However, Eskom fell short of its target of 60% for 31 March 2023, landing on 56%, said Cassim. 

The power utility’s EAF is currently sitting at 52%, he said. 

André de Ruyter ‘broke trust’

Makwana said former Eskom CEO André de Ruyter broke trust “in the most repulsive manner possible” and breached several laws, including access to personal information and corporate governance laws, with the publication of his book.  

“In the course of publishing this book, transgressions were carried out by an executive who was in fiduciary position, in possession of proprietary information of a national keypoint, who himself evaded being vetted by processes that involve our national security services agency,” said Makwana. 

Read in Daily Maverick: André de Ruyter’s Truth to Power: The bombshell information uncovered by private intelligence

Eskom’s corporate governance teams are reviewing the former CEO’s statements and will take the appropriate steps to ensure the board takes all necessary action. 

It will also be conducting an independent investigation into the veracity of the allegations made.  

Meanwhile, the Eskom board has made “good progress” with the search for a new Eskom boss, said Makwana, and should soon be appointing a new CEO. DM