Stage 2 load-shedding will be implemented for the fifth time this week, running from 17:00 to 22:00 on Friday, Eskom said in a statement.
Several generating units are expected to return to service starting on Friday afternoon and through the weekend, however.
"Eskom will continue to closely monitor the system with a view to adjusting the stage of load-shedding accordingly," said spokesperson Sikonathi Mantshantsha.
Since Thursday afternoon a generating unit each at the Majuba, Tutuka, Grootvlei, Kriel and Matimba power stations were returned to service.
"This, however, is still insufficient to suspend the implementation of load shedding as a generation unit each at the Kriel, Kusile, Majuba, Camden, Matla power stations either tripped or were taken offload for repairs," Mantshantsha said.
One generation unit at Kusile Power Station is expected to return to service this afternoon.
A total of 2 094MW s out on on planned maintenance, while another 16 305MW of capacity is unavailable due to breakdowns.