Eskom has implemented Stage 4 load shedding until 5am tomorrow.
Breakdowns are currently at 16,468MW of generating capacity while the capacity out of service for planned maintenance is 4, 601MW.
"In the same period a generating unit each at Arnot, Grootvlei, Kendal and Majuba power stations was returned to service," the utility said.
The anticipated return to service of a generating unit at Matla power station has been delayed, further contributing to the current capacity constraints.
In a short statement this afternoon, Eskom said Stage 2 will then be implemented from 5am on Saturday until 4pm, followed by Stage 4 until 5am on Sunday.
"The patten will be repeated on Sunday. Eskom will publish another update should any significant changes occur," Eskom crisis communication manager, Menzi Mngomezulu said.
"We appeal to the members of the public to continue reducing demand by switching off non-essential appliances. We would like to thank those who do heed the call to use electricity sparingly and efficiently, including switching off geysers and pool pumps from 5pm to 9pm, as this lowers demand and helps in alleviating the pressure on the power system and contributes to lower stages of load shedding," he said.