17 July 2012 – At the start of this week South Africa’s power utility Eskom was closely monitoring weather conditions around the country, after snow and heavy rain had affected power lines and sub-stations in the Cape and elsewhere over the weekend. Some customers, particularly in the Eastern Cape, experienced power outages as the result of the storm damage but supply was restored in almost all areas. Eskom had anticipated inclement weather and had staff, helicopters and equipment on standby. This enabled it to respond rapidly to repair damaged infrastructure, despite difficulties in accessing sites.

However, the extremely cold weather resulted in the national peak demand, particularly during the evening peak hours between 5 PM and 7 PM, reaching annual highs. Eskom expected a demand on Monday the 16th of July of about 36,258 MW, the highest so far this winter and urged its customers to switch off all non-essential electrical appliances during the peak hours as the available supply was only 36,580 MW including open cycle gas turbines. Though warmer weather is expected later this week, the system remains tight, and Eskom urges all South Africans to help it keep the lights on.
 
Koeberg Unit 1 has been returned to service after it shut down automatically on Wednesday evening last week due to an electrical fault on the non-nuclear side of the unit. The fault has been dealt with and there were no interruptions to power supply as a result of the shutdown.  

On Monday planned maintenance stood at 2,250 MW and unplanned outages at 4,100 MW. Peak demand for Tuesday was forecast at 35,825 MW, Wednesday at 35,535 MW and Thursday at 35,464 MW.

Eskom says that South Africa’s power system is expected to be constrained for at least the next two years.