Eskom is running on fumes with at least four power units failing.
And should it run out of diesel and water, the country can reach up to stage 6 of load shedding.
This was revealed on Wednesday as the power utility switched to Stage 4 load shedding shortly after 7am.
The country will experience Stage 4 until Friday at 5am, Eskom said.
City of Cape Town customers will be slightly less inconvenienced during this period, however, experiencing Stage 1 from 5am to 10am, and Stage 3 from 10am to 10pm.
The power supplier has found itself between a rock and a hard place as it tries to balance its limited resources, including a shortage of diesel, water and money.
In a media briefing, Eskom’s chief operating officer Jan Oberholzer said it was “critically important” to balance emergency resources to avoid a crisis.
Overnight, a generation unit at each of Kendal, Duvha, Camden and Kusile power stations tripped.
To save the country from disaster, they had no choice but to go to Stage 4 load shedding.
“This being the fourth day of extremely high diesel usage, the emergency reserves are being depleted faster than can be replenished.
“Stage 4 load shedding will therefore give us the space required to replenish the emergency reserves and continue to manage the system safely,” Eskom said.
Open cycle gas turbines cost R700 000 per unit per hour to run and use 14 litres of diesel a second, Oberholzer said.
Oberholzer said the open cycle gas turbines were designed for morning and evening peaks but are now being used extensively to keep the lights on.
He said they expect to return seven generating units by the weekend.
Giving a description of the units that are currently operating, Oberholzer said that three were running at a very high risk, 10 at a medium risk and three at a low risk.
“We have 80 units that need maintenance.
“It’s like a car, you have to do maintenance again after a while,” he added.
The COO said they are finding themselves with an unreliable and unpredictable system and are looking for gas alternatives.
He said Eskom CEO Andre de Ruyter is currently in Washington D.C. in the US to have discussions with the World Bank and other parties on plans to move away from coal power.
Asked if Eskom was supplying any Southern African countries with power, he said during load shedding, they stop supplying “unfirm contracts”, while reducing 5% per stage on exports for “firm contracts”.
He added that South Africa was only getting power from Cahora Bassa in Mozambique.