Stage 1 rotational loadshedding has been implemented from 12:15 and is likely to continue until 22:00 on Sunday to preserve emergency resources, Eskom said in a statement.
Customers are reminded to treat all electrical points as live during loadshedding, Eskom said.
Customers are advised to keep checking their loadshedding schedules on the Eskom and their municipal website, and to plan on the assumption that load shedding will take place.
"We continue to appeal to residents and businesses to use electricity sparingly during this period. Please switch off geysers as well as all non-essential lighting and electricity appliances to assist in reducing demand," Eskom said in the statement.
Fin24 reported earlier this week that Eskom is running low on coal; municipal debt has ballooned by another R2bn since May and the risk of load shedding is "very high".
More information on Eskom's loadshedding schedule is available here.
UPDATE: City Power in Johannesburg said in a statement issued by mid-afternoon on Sunday that is has been notified by Eskom that it is implementing stage 1 load shedding from 12:14 to 21:00. The reason given is to preserve "emergency resources".
Therefore. City Power will have a stage 1 load shedding in Block 4B areas from 12:00 to 16:30, affecting substations including Prospect, Cleveland, Wemmer, Moffat SS, and Crown SS.
Suburbs affected include Tuffontein, Reuven, Haddon, Kenilworth, Rosettenville, West Tuffontein, La Rochelle, South Hills, Linmeyer, Oakdene, The Glen Shopping Centre, part of Bassonia, Regents Park, Rewatch, Glenesk, Stafford, Townsview, Towerby, Rosana.
Also, from Crown Substation Booysens Reserve, Nasrec, Frampton Theta, and part of Ormonde are affected and from Moffat substation Tulisa Park, Elandpark, Unigray, Electron, Moffat View, City Deep are affected.
City Power said it will provide further updates on those that will be affected from 16:30.
City Power will also keep customers updated should the situation change from Eskom's side, either on the stage or times of load shedding.
It urged its customers to use electricity sparingly and to switch off non-essential electricity appliances.
"We apologise for the inconvenience this is causing," said City Power.
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