Why there is no load-shedding — and how quickly that could change

Photovoltaic solar power is having a tremendous impact on Eskom’s ability to avoid rotational power cuts.

This is according to Eskom System Operator head Isabel Fick, who was responding to questions during a media briefing on Friday.

Fick explained that the contributions of solar power plants and rooftop solar installations were allowing Eskom to replenish its pumped storage capacity during the day rather than at night.

Eskom can then use its emergency generation capacity, which includes pumped storage and diesel-powered open-cycle gas turbines (OCGTs), over the evening peak when solar energy is unavailable.

However, if the weather turns, so does South Africa’s load-shedding fortunes.

South Africa is currently enjoying 30 consecutive days of no load-shedding.

Although this is partly due to Eskom’s steadily improving coal-fired power plant performance, sunshine currently plays a more significant role.

Fick said that around 2,800MW of photovoltaic solar is directly connected to the Eskom grid.

For “behind-the-meter” solar, Eskom estimates that there is around 5,440MW installed.

“That would refer to rooftop PV as well as small plants that are not connected to the Eskom system,” said Fick.

“Unfortunately, when we don’t have the sun shining — as we have seen just before this period [without load-shedding] — we then have to lean back on our emergency resources, and then the picture changes,” Fick stated.

This is demonstrated in Eskom’s March-April generation data for 2023 and 2024.

Eskom’s current winning streak had many speculating that the state-owned power utility was burning massive amounts of diesel to keep the lights on ahead of the elections.

However, Eskom says it’s used less than half the diesel budget this April compared to the same month last year.

Its data shows that Eskom’s usage of its OCGT emergency reserves was consistently high last year.

Eskom burned through R2.1 billion of diesel in March last year and R3.1 billion in April.

This year, it spent R3.3 billion on diesel in March, and to date has only spent R1.4 billion in April.

source:Why there is no load-shedding — and how quickly that could change (mybroadband.co.za)