Generating plants are still performing at very low levels of reliability, Eskom said, with some unplanned breakdowns at 06:00 on Friday morning.

Load-shedding will only be implemented if absolutely necessary, the power utility promised. It added that there is currently sufficient diesel for its open cycle gas turbines and water at the pumped storage schemes to supplement the shortage of capacity, if required.

Unplanned outages above 9 500 MW mean Eskom has to resort to emergency power generation by using open cycle gas turbines and pumped-storage hydroelectric plants. These are very expensive ways of generating power, particularly the gas turbines, which require large quantities of diesel.

The system is closely monitored, but any unexpected shift, such as additional unplanned breakdowns, could result in load-shedding at short notice.

Eskom has not yet provided an indication of the prospects of load-shedding for the weekend.

Fin24