Load-shedding is not expected on Thursday, but Eskom is using emergency reserves as some generation units have been taken off the grid for emergency repairs, the power utility has said.

In a statement issued on Thursday morning, Eskom said supply had to be supplemented as some generation units had been taken out for urgent maintenance. "As such, the system remains constrained, vulnerable and unpredictable," it said. 

As at 07:05 on Thursday, unplanned outages or breakdowns were at 11 190 MW. Planned maintenance stood at 4 417MW.

The cash-strapped power utility has warned of an increased likelihood of power cuts over the next 18 months as it conducts maintenance on its fleet of ageing power plants.