Eskom announced on Friday that it would implement 13 hours of stage 2 load shedding between 09:00 and 22:00.
The rotational power cuts are "as a result of loss of additional units overnight".
"Stage 2 calls for 2 000MW to be rotationally load shed at any given period. Load shedding is conducted rotationally as a measure of last resort to protect the power system from a total collapse or blackout," Eskom said in a statement.
"We encourage residents and businesses to please use electricity sparingly to ease the demand of electricity. Please switch off geysers during the day as well as all nonessential lighting and electricity appliances to assist in reducing demand."
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