Johannesburg - Demand for electricity has increased as cold weather sets in, Eskom said on Thursday.
The effect is particularly noticeable during evening peak hours from 17:00 to 21:00.
"The most critical period within this peak is from 5pm
until 7pm as a large number of customers return home from work," it said
in a system status bulletin.
"Eskom has made planned maintenance of its power stations a priority."
The power utility has been making significant progress with its programme of preventative maintenance to help stabilise the power system.
Total demand on Thursday evening was forecast to reach 34 274 megawatts (MW).
Eskom had 36 847 MW of capacity available, including from open cycle gas turbines.
Current planned maintenance accounted for a further 3 365 MW. Unplanned outages affected 2 990 MW.
On Wednesday, peak demand of 33 698 MW was met with an available capacity of 36 703 MW.
Demand and capacity figures were similar for Monday and Tuesday.
Peak demand for the rest of the week was forecast to
reach 32 289 MW on Friday, 31 529 MW on Saturday, 32 176 MW on Sunday,
34 386 MW on Monday, 34 271 MW on Tuesday and 34 227 MW on Wednesday.
"We urge all South Africans to partner with us to keep
the lights off and save 10% of their electricity usage," the
This will make it easier to manage the power system, enabling Eskom to carry out planned maintenance of its plants.