Eskom has announced three days of stage four load-shedding, starting at noon on Wednesday.
“Due to further shortage of generation capacity, Eskom regrets to announce that stage four load-shedding will be implemented from 12pm today until 5am on Friday,” the power utility said.
It added that it would then revert to stage two load-shedding until 5am on Saturday.
Eskom said, over the past 24 hours, it had been forced to shut down a unit at Lethabo power station and one at Arnot; meanwhile, Medupi, Kusile and Matla each had one unit trip.
“This constrained the power system, further requiring extensive use of emergency reserves and, therefore, hampering the recovery of these reserves,” it said.
“Total breakdowns currently amount to 14 957MW while planned maintenance is 5 301MW of of capacity.”
This translates into a loss of well over half the power utility’s coal generation capacity of about 37 000MW, which was the case on Saturday night as well.
The stage four announcement comes days before the local government polls and days after Eskom warned that the system would remain constrained until the end of August next year. It meant, the power utility said, that it would have to rely on open-cycle gas turbines to prevent load-shedding, or more likely, ameliorate its severity.
Eskom said some generating units have returned to service and it expected another two to return on Wednesday. Unit one at Koeberg was expected to return to service on Wednesday as well, and to return to full output within the next 48 hours.
The utility apologised for the inconvenience consumers will experience as they endure outages of four hours at a time, but said implementing stage four should not be seen as cause for alarm.
“Eskom would like to apologise for the inconvenience caused by the implementation of load-shedding, and requests the public to reduce the usage of electricity in order to help us through the constraints.”
The power utility has said it would seek to avoid load-shedding during the local government elections on Monday.
Chief operating officer Jan Oberholzer said it would do so by drawing on its emergency reserves during the day and replenishing them at night.
The utility’s inability to keep the lights on in the run-up to the poll has become a campaign ticket for opposition parties.