Stage 6 ‘good’ amid high demand – expert

Professor Hartmut Winkler from the University of Johannesburg’s Faculty of Physics said considering the current high electricity demand, stage 6 load-shedding is “reasonably good” as higher stages were expected to be implemented.

Since the start of winter, South Africa has been experiencing less load-shedding than initially predicted. This has largely been due to lower-than-expected demand and fewer breakdowns at Eskom.

However, the utility ramped up load-shedding this past week, returning South Africa to stage 6 for the first time in around four weeks.

Eskom attributed this to prolonged high demand due to colder weather and the failure of some generator units.

According to Winkler, this week is likely the highest demand that the country will face this year, and the demand on Monday and Tuesday nights was the highest Eskom has dealt with all year. 

“The fact that we’re only on stage six under such circumstances is actually reasonably good,” he told SABC.

“I was expecting that this winter we would at some point go to stage 8 – that may still happen, but it hasn’t so far.”

Winkler said Eskom’s regression was attributed to more frequent breakdowns, but the utility has been vague about the nature of these breakdowns.

He said this makes it difficult to predict when South Africa will return to lower load-shedding stages.

However, Eskom currently has large power stations on very long outages. For example, Kusile – the largest power station in the country – is not in operation, and its repairs will likely only be completed by the end of the year.

Therefore, Eskom relies on its OCGTs and smaller power stations to meet demand. This means that, depending on the nature of the breakdowns, South Africa could return to lower stages in a matter of days, or it could take months.

However, Winkler is sceptical of whether the utility will be able to fix its problems in only a matter of days, and expects load-shedding to stay between stages 3 and 6 for the rest of July.