Power utility Eskom will implement Stage 2 load-shedding from 16:00 on Monday afternoon until 05:00 on Tuesday morning.
It has also warned that there is a possibility that load-shedding would continue throughout the week.
The utility noted that it has had to resort to load-shedding as a result of the cold front setting in earlier than expected, as well as high breakdowns of generation units.
Breakdowns total 14 560 MW of capacity, while another 2 300 MW is unavailable as a result of planned maintenance, it said on Monday afternoon.
"Some generation units are expected to return to service starting this evening, which will help ease the strain.
"This, however, is not sufficient to eliminate the high probability of load-shedding for the rest of the week," it added.
Eskom stated that generation supply constraints would persist throughout the high winter demand period, which increases the likelihood of load-shedding.