Stage 4 loadshedding will be implemented at 05:00 to 16:00 from Tuesday, followed by Stage 5 load shedding at 16:00 to 05:00 from Wednesday, Eskom warned.
Over the course of this week, 14 generators are expected to return to service, helping to ease the pressure on the power system, the utility said.
Also, Eskom bought an additional 50 million litres of diesel on 6 January 2023.
"This fuel will be utilised sparingly to manage the pumped storage dam levels and to limit the amount of loadshedding during the day," Eskom said. Together, these emergency generators contribute 5 700MW of capacity.
A generating unit each at Kendal, Majuba and Tutuka power stations have returned to service on Monday.
There are currently 12 generators out on planned maintenance, representing 5 804MW of capacity. Breakdowns currently amount to 16 173MW of generating capacity.