Eskom says it will reinstate stage two load shedding from midday to 23:00 on Friday.
It says it will start with stage one at 09:00 and switch to stage two at midday.
This despite Eskom Acting CEO, Jabu Mabuza reporting on Thursday night, that while stage one load shedding would still be imposed on Friday, no further power cuts were expected for the foreseeable future.
Mabuza said Eskom was left with no choice but to implement load shedding after six power stations were shut down due to boiler tube leaks.
On Friday however, the power utility said since the media briefing on Thursday night it has had a major setback, as it has lost additional capacity from the Medupi power station.
Eskom says it has lost three units at Medupi due to coal and ash handling issues. It says this is in addition to the conveyer belt that failed at the station on Saturday last week.
This means that the power system has deteriorated further, creating an additional shortage of generation capacity of about 1 500 megawatts.
Eskom says it understands the negative impact this will have on its customers, in particular matriculants, who are writing exams on Friday morning.
Watch the Eskom briefing below: