Eskom warned consumers in Gauteng on Wednesday that it is very concerned about a significant increase in network overloading.
It said this was due to illegal electricity activities across high-density areas in the province, and appealed to the public to stop using electricity indiscriminately or illegally and not to bypass meters.
High demand periods are between 05:00 and 09:00 and 17:00 and 22:00.
Eskom has been announcing load reduction in multiple provinces in recent days in a bid to avoid network overloading in high-density areas.
On Sunday the power utility announced load reductions at peak times in the Free State, Gauteng, Limpopo, the North West province and KwaZulu Natal.
On Wednesday, Eskom issued a load reduction notice for Limpopo, Mpumalanga, the Eastern Cape, the Free State, Gauteng, KwaZulu-Natal and North West from 17:00 until 22:00.
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