Eskom on Friday evening warned South Africans to plan for a weekend of load shedding.
The power utility said the probability of stage 1 rotational power cuts over the weekend was high due to a shortage of capacity.
This was caused by a combination of plants being down due to planned maintenance and a "higher than expected" number of units not working due to unplanned maintenance caused by technical faults.
"Cahora Bassa hydropower plant is still supplying 700 MW less to the grid as a result of a damaged transmission line, which occurred late on Wednesday. There is also a need to preserve emergency water and diesel resources to limit the load shedding possibility or magnitude thereof in the following week," it said.
As of 16:00 on Friday Eskom was conducting stage 2 load shedding which it expects to continue until 22:00.
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