Johannesburg - The risk of blackouts is medium to high on Monday, power utility Eskom said.
"Should anything unexpected happen on the generation side we may need to go into load shedding," its media desk said.
Eskom urged its customers to use electricity sparingly to ease the pressure on the power grid.
In a statement on Sunday evening, Eskom said it stopped stage 1 load shedding at about 20:00 on Sunday, earlier than expected, but added that restoration of power could take longer in some areas.
READ: Stage 1 load shedding to begin
"The electricity supply system remains very vulnerable due to a shortage of generation capacity as several units are currently out of service due to planned and unplanned outages. Any unforeseen incident in the power system will thus trigger the implementation of load shedding."
It warned that as Eskom is currently experiencing its maintenance season, the power grid is expected to remain constrained for the rest of the summer.
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