Eskom has revealed that, in the worst-case scenario, South Africa will be load-shed for 295 days — or 81% of the year — between April 2022 and 2023.
What’s worse is that, in the scenario, Eskom would have to burn more than R35.9 billion worth of diesel to run its open-cycle gas turbines (OCGTs) while maintaining up to Stage 4 load-shedding.
The power utility doesn’t believe it is viable to run its OCGTs at this level.
“History has shown that it is not possible to use more than about R1.2bn of diesel in a month due to the physical limitations of moving the diesel to the OCGT stations,” Eskom noted in its State of the System presentation.
However, its worst-case scenario would see nearly R3 billion worth of diesel being burnt each month.
Eskom provided three scenarios for expected load-shedding between April 2022 and 2023 — Base Case, Base Case + 1,500MW, and Base Case + 3,000MW (or worst-case scenario).
It should be noted that Eskom has adjusted its scenarios since October 2021, upping the intervals from 1,000MW to 1,500MW.
The Base Case — or most optimistic — scenario accounts for a maximum difference between peak demand and available generation capacity of 12,000MW over the winter months. This will increase to 13,000MW in summer.
Its forecast for these scenarios paints a grim picture.
The other two scenarios were stress-tested to determine the impact should the 12,000MW and 13,000MW thresholds be exceeded.
South Africa would see a maximum of 16 days of load-shedding in the Base Case outlook, with diesel costs to run OCGTs reaching R6.2 billion over the year.
However, the country is already beyond the Base Case scenario, which showed that Stage 1 would be the highest level of power cuts Eskom would implement.
The same can be said for Eskom’s Base Case + 1,500MW — or neutral outlook, which shows that South Africa could experience power cuts up to Stage 3 at the worst. The country already experienced Stage 4 load-shedding in mid-April.
Eskom also won’t be able to run its OCGTs at the levels required for the neutral scenario. The power utility would have to use R19 billion worth of diesel through the year — or almost R1.6 billion each month.
In other words, Eskom would have to load-shed at a higher stage to make up the difference between what it can spend on OCGT diesel, and what the theoretical scenario demands.
Eskom relies heavily on its OCGTs to compensate for load losses and reduce the difference between demand and capacity.
As of 31 March 2021, the use of these plants had cost the power utility R6.4 billion. It will exceed its year-end projection of R8.5 billion OCGT expenditure at the current rate.
According to data provided by EskomSePush, South Africa is on track for the middle-ground scenario despite Eskom low-balling the maximum stage, as the country experienced eight days of load-shedding in April.
The country barely had load-shedding during April since 2020, which indicates that the system could be worse off than it was around the same time last year.
This is reflected in Eskom’s latest weekly system status report, which revealed that the energy availability factor of its fleet for the year was 58.64%, compared to 61.79% in 2021