Eskom is implementing Stage 2 load-shedding from 16:00 to 24:00 on Wednesday and Thursday. 

"The delay in returning a generation unit to service each at Arnot, Koeberg and the Kusile power stations, as well as the unplanned outage of a generation unit each at Camden, Medupi and two units each at Grootvlei, Hendrina and Majuba power stations, have exacerbated the capacity constraints," Eskom said. 

Some units are expected to return to service over the next few days. 

Eskom currently has 2 931MW on planned maintenance, while another 15 051MW of capacity is unavailable due to breakdowns.