Government is worried about the economic impact of power cuts following the collapse of a coal silo at an Eskom power station, Minister in the Presidency Jeff Radebe said on Wednesday.

"Yes, we are worried... that is why we are impressing upon Eskom to do everything it can to solve whatever problems there are in that silo that was affected," he told reporters at a briefing in Cape Town, following Cabinet's fortnightly meeting on Wednesday.

There have been power cuts around the country after a coal silo collapsed at Eskom's Majuba power station in Mpumalanga on Saturday, severely affecting the utility's ability to meet national electricity demand.

Radebe said as of Wednesday, Eskom had brought an additional 3 000 MW on stream.

"The mere reason that in the state-of-the-nation address President [Jacob Zuma] highlighted energy as our topmost priority is a reflection of the seriousness with which we see the issue of energy.

"Without energy we'll not be able to fire the re-industrialisation of the South African economy, so that's why this energy mix is of critical importance."

Government's target was to add about 10 000 MW of electricity to the national grid by 2019.

Responding to a question on the under-construction of Medupi power station in Limpopo, he said this was still on track.

"Our understanding is that the timetable that was made by Minister of Public Enterprises [Lynne Brown] about a month or so ago is still on track in terms of Medupi -- the switch on."

In September, Brown said Eskom would synchronise the first of Medupi's six units to the grid on December 24.

Earlier on Thursday, Radebe noted the country's power grid was under severe strain and called on all to help save electricity.

"Cabinet would like to reassure South Africans that everything is being done to address these challenges," he said.