South Africa's crushing electricity outages could end sooner than expected as power generation is being ramped up, an upbeat cabinet minister said on Sunday.

The state energy firm Eskom has been imposing daily scheduled blackouts, called load-shedding, to safeguard the grid whenever demand outstrips supply due underperforming power plants.

These started on very low level some 15 years ago, but scaled up to devastating stages last year which left consumers without power for up to total of 12 hours per day. But the outages have in recent weeks drastically dropped to just around two hours a day.

"We will resolve load-shedding," Electricity Minister Kgosientsho Ramokgopa told reporters in Pretoria on Sunday.

"I think that we will resolve it much quicker than we had anticipated. The date is within the horizon," he said, without giving a specific date.

He said more than 100 best generation experts from Eskom, government and private sector have been mobilised and deployed at the worst-performing power stations to boost output.

Demand had also slowed as consumers saved power by switching off unnecessary appliances, he said.

Peak winter demand, projected at 34,000 megawatts, has been down at 30,000 megawatts, he said.

Power cuts have also forced many South Africans, who had become hardened to the rolling outages, to find alternative sources such as installing rooftop solar units at the household level.