Eskom started implementing stage 2 load shedding from Tuesday and said it would continue for the rest of the week.
Eskom said load shedding would end on Monday at 5am.
It said this has been caused by a shortage of generation capacity owing to delays in returning generators to service, as well as breakdowns of nine generators.
On Sunday generation units at Lethabo, Tutuka, Ingula, Drakensberg, Arnot as well as two units each at Hendrina and Matla power stations suffered breakdowns.
Further delays in returning generators to service at Arnot, Kendal and three units at Tutuka power stations have added to the capacity constraints.
Eskom said it has had to rely on the use of emergency generating reserves to limit the stage of load shedding during this period.
“We currently have 3 875MW on planned maintenance, while another 15 067MW of capacity is unavailable due to breakdowns.”
They urged the public to use electricity sparingly.