The power utility says load shedding may worsen this winter as it battles with electricity outages attributed to its antiquated power stations.
Eskom has declared a power emergency as a result of severe constraints on the national power grid.
The power utility has asked industry to cut energy use and declared an emergency, noting load shedding as a virtual certainty.
Ahead of winter, the power utility says it will continue with its maintenance strategy and will see a reduction in the maintenance schedule.
Eskom has released two warnings within hours: switch off non-essential appliances or face load shedding; and prepare for another rate hike.
After a week of rain left coal stocks wet, Eskom says the country could experience power cuts after declaring an emergency.
Eskom has declared an electricity supply emergency and is urging customers to curtail power usage.
PODCAST: We find out how the setback at Eskom's Medupi power station will affect the country's power supply and economic growth.
Eskom had to briefly cut supply to one of BHP Billiton's aluminium smelters on Monday night after nationwide demand outstripped supply.
The power supplier has no idea how to manipulate its customers: peak pricing is what's needed.
It was "too risky a commitment to make" to say there would be no load shedding in the coming months, says Minister in the Presidency Collins Chabane.
With Eskom's rolling blackouts highly likely this winter, consumers have no choice but to switch off.
A massive power failure has hit India for the second day running as three regional power grids collapsed, blacking out more than half the country.
Eskom says South Africans have to reduce their electricity use by a tenth, so it can take power stations offline for dangerously overdue maintenance.
Eskom has warned of a very high risk of rolling blackouts around SA, but says it has been doing everything it can to avert the "load-shedding".
Eskom has paid executive committee members 109% more in 2011 than last year, according to its financial statements for the year ended March 31.
Eskom -- which is struggling to keep the lights on -- has been interrupting supplies to BHP Billiton's smelters to help manage its tight supplies.
Eskom said using electricity could stave off the re-introduction of load shedding as cold winds and snow dragged temperatures down to single digits.
SA may face fresh power cuts early in 2009 because the level of voluntary energy savings has fallen below the required 10%.