Cape Town - Eskom has implemented stage 1 load shedding from 10:00 until 22:00 on Friday "due to cold weather as a result of the cold front and the shortage of generating capacity".
"Any unexpected changes on the vulnerable and constrained power system could lead to a change in the load shedding stage at short notice," it said in a statement on Friday.
The City of Cape Town tweeted that Area 11 would experience load shedding from 10:00 to 12:30.
See how you will be affected: GridWatch
On Thursday, Eskom shifted its stage 1 load shedding to stage 2, which meant it needed to increase its 1 000 MW electricity cut to 2 000 MW.
"The electricity system remains significantly constrained ... for the rest of the week into the weekend and next week as demand surpasses available supply," Eskom said in a power update on Thursday.
"With continued cold weather forecasted for the next few days due to a cold front, the system is expected to be constrained during the evening peak period (17:00 – 21:00).
"We therefore request all electricity users to save as much as they can in order to limit the severity of load shedding. Eskom will provide regular updates on the status of the power system through all the media platforms.
Eskom will implement Stage 1 load shedding from 10:00 this morning. This is likely to continue until 22:00 this evening.
— Eskom Media Desk (@Eskom_MediaDesk) May 8, 2015
"We would like to thank all electricity users for responding to our calls to save and we urge everyone to save as much as they can because every little bit counts. "We have asked our industrial customers to also contribute towards savings through load curtailment and we also want to thank them as their response goes a long way in addressing capacity constraints.
"Eskom calls on all customers to reduce the load on the electricity grid by urgently switching off geysers, air conditioners, pool pumps and all non-essential appliances throughout the day, which will reduce electricity demand.
"We would like to thank all customers who continue to use electricity sparingly. Every little bit of saving counts as it reduces the severity of load shedding.
"Eskom calls on all South Africans to pull together over the next few months and use electricity sparingly. Homeowners and businesses can do so with just four steps: first, switching off geysers and pool pumps; second, switching off non-essential lights; third, efficient use of air-conditioners by keeping the room temperature at 23°C; and finally, responding to the alerts on TV each evening."