On Wednesday morning, Eskom group CEO André de Ruyter admitted to Parliament that a recent fire at unit 5 of the Kusile Power Station may delay the unit's completion by a whole year, until December 2024.

A month ago, a fire broke out at a gas air heater at unit 5, which is being commissioned and has not yet been synchronised to the grid.

De Ruyter told Parliament's Standing Committee on Public Accounts that the fire would set back Eskom’s work on the unit by a year.

"Unfortunately, I have to be open, unit number five will not be placed in commercial operation in December of 2023,” De Ruyter said. “Again, I need to emphasise that [the fire] was during the commissioning of that component and we don't believe that there was any foul play," said De Ruyter.

He said that the preliminary estimate is for a delay of 12 months, but this could be shortened following some internal "arm wrestling" in Eskom.

De Ruyter said the incident is projected to cost Eskom R150 million per month, which is related to the delays in getting the nearly 800 MW unit online much later than expected.

De Ruyter said the Eskom management would have a better understanding of the fire and its causes by the end of the weekend. He said unit six was still on track to come online in the middle of 2024.

He told the committee that Eskom management was keeping track of the costs at Kusile and Medupi.

The Eskom board approved a budget of R145 billion for the work on Medupi. "We have spent R126-billion. That gives us a R19-billion variance. We will be within that R145-billion and (for) Kusile it's still that R161.4-billion," De Ruyter said.

He said the plant defects at both Medupi and Kusile included poor performance of the pulse jet fabric filter plant due to an inadequate pulsing system, mechanical performance, erosion, furnace exit gas temperature resulting in excessive reheater spray water flow, and flue and gas ducting erosion.

Kusile and Medupi, two of the world’s biggest coal-fired power plants, were commissioned in 2007 and were supposed to be completed in 2014. But severe design defects at the two power stations are expected to take until 2027 to rectify fully.