No major relief to the power shortfall in the form of large new power generating units will happen before next year. South Africans therefore have to brace for the winter power shortages. South Africa’s electricity daily peak consumption rises from a summer average of 32 GW to 36 GW in winter. This is caused by the increased use of electrical heating devices, as well as the longer use of lights and increased geyser consumption.
Eskom has tried to maximise the operation of its power plants in the colder months by scheduling plant maintenance during the warmer seasons. This strategy is being adopted again in 2023 and will provide some relief. But there are too many plants that are going to be out of operation for the entire winter season.
My estimations suggest that the mid-winter power shortfall will be of the order of 2 GW greater than it was in 2022. Deficits of 8 GW (referred to locally as “Stage 8 loadshedding” – the highest level of power outages) can therefore be expected on some days.
The danger of a grid collapse
A national blackout triggered by the current oscillating frequency of the grid drifting too far from the prescribed 50 Hertz would raise the danger of the power grid collapsing. This would happen if points along the grid – including power plants – tripped one after the other, resulting in zero electricity everywhere.
Re-energising the grid would be a slow process achieved one station at a time. Many days of economic activity would be lost before full electricity supply is recovered. The consequences would be far reaching, and would include possible looting and vandalism. It could also lead to fuel shortages, which in turn would affect transport and industry and a host of facilities that use backup generators such as hospitals, laboratories and morgues.
Rolling power cuts are the best practical way to prevent a grid collapse and total blackout. Eskom is therefore at pains to always keep the generated power higher than the power used. It does this by cutting access to electricity to some users.
A prompt reduction in power usage through the speedy implementation of tougher electricity cuts would always prevent a grid collapse. Nonetheless, a grid collapse cannot be ruled out if, for example, a set of poorly performing coal plants all break down in quick succession. As South Africa’s new Electricity Minister has warned, the winter of 2023 is going to be challenging. The Conversation