State power utility Eskom is expected to implement Stage 3 and 5 load shedding until Wednesday evening.

Stage 3 will be implemented between 5am and 4pm, with Stage 5 following between 4pm and 5am.

On Monday afternoon, the power utility said unplanned breakdowns amounted to the unavailability of some 14 940MW of generating capacity, with a further 7 215MW out due to maintenance.

Eskom said although a generation unit was returned to service at Lethabo and Matimba power stations, respectively, since Sunday, breakdowns and delays in return to service have caused further strain on the power grid.

"In the same period, two generating units at Kriel Power Station and a generating unit at Kendal Power Station were taken offline for repairs. The delays in returning a unit to service at Camden, Lethabo, Kriel, Medupi and Tutuka power stations have contributed to the capacity constraints.

"Further, the expected increase in demand after the Easter weekend will put additional strain on the power generation system and may require an increase in the stage of load shedding at short notice.

"We thank all South Africans who continue using electricity sparingly and efficiently in helping to alleviate the pressure on the power system," Eskom said.