"Eskom wishes to assure the public that implementing loadshedding is the last resort, in order to protect the national grid. This loss added to breakdowns at the Kriel and the Medupi power stations because of difficulties experienced during startup," said the company via a statement. 

Eskom's teams were working around the clock to return as many generation units as possible, it said.

The colder weather also meant demand for electricity has risen significantly.

"We therefore urge the public to continue assisting us in managing consumption in order to reduce the impact of the supply constraints."

The company would communicate any significant changes to the supply situation, it said.

Before resuming loadshedding on Friday last week, Eskom sent out a number of warnings about constrained supply in the past month. 

Although loadshedding - a now common occurrence in South Africa - was suspended during the country's hard Covid-19 lockdown, an increase in demand due to winter weather, industries reopening during eased lockdown levels, and multiple breakdowns due to poor maintenance over decades has seen the return of rotational blackouts. 

African News Agency