Electricity Minister Kgosientsho Ramokgopa attributed the “unwelcome” ramp-up in the intensity of loadshedding to Stage 6 to a need for Eskom to rebuild its emergency reserves that had been depleted by the failure of large coal units during the week and a 1 500 MW spike in demand, which was attributed to the heat-wave conditions affecting parts of the country.

Eskom implemented Stage 6 loadshedding at midday on November 24, a period that coincided with the yearly Black Friday retail event, during which shoppers flock to malls to take advantage of price specials.

The utility also indicated that it intended sustaining the same level of loadshedding intensity until 5:00 on Monday morning. During Stage 6, power is interrupted in some areas for between 8 and 12 hours in a day.

Speaking at a briefing organised hastily after the declaration, Ramokgopa said that although unplanned breakdowns and partial load losses were elevated at 15 600 MW and planned outages stood at 5 800 MW, Eskom would not typically have needed to resort to Stage 6 loadshedding over a low-demand weekend period to offset such losses.

However, demand on Friday had risen to 1 500 MW above that experienced on Thursday, which Eskom Generation executive Bheki Nxumalo attributed to a higher use of air-conditioners. This, coupled with a requirement to replenish dam levels at the pumped storage schemes and rebuild diesel stocks, particularly at the Ankerlig open-cycle gas turbine, had led to the decision to implement Stage 6.

The emergency generators had been used extensively during the week, when large units failed at power stations such as Medupi, Lethabo, Duvha and Majuba.

Nxumalo insisted that Ankerlig’s diesel stocks were not being directly affected by the congestion at the Port of Cape Town and said the rate of replenishment was instead limited by the usual road-logistics constraints associated with the restocking of the facility.

Ramokgopa also insisted that there had been no reversal in the recovery trend across the coal fleet and forecast that there would be “significantly lower levels of loadshedding” in December, even predicting that there would be some days when no loadshedding would be implemented.

He acknowledged, though, that the loadshedding threat could only be eliminated with the introduction of new generation capacity, and said actions were being taken to unlock private capacity and resume public procurement.

However, no firm date was provided for the resumption of public renewables procurement, which was initially scheduled to resume in the middle of 2023, but which had been delayed because of ongoing uncertainty over grid allocations.

A further system briefing would be held on Sunday.