Embattled State-owned utility Eskom has denied having implemented either Stage 7 or Stage 8 loadshedding during what it acknowledged to have been a “tough week”, during which it reported power cuts exceeding 7 000 MW over some evening peaks.

Each stage of loadshedding typically equates to 1 000 MW.

Acting generation executive Thomas Conradie confirmed that there had indeed been a risk of exceeding Stage 6 during the week, when high levels of unplanned outages were further amplified by the shutting of all but one of the six units at the normally reliable Lethabo power station for a period, owing to coal constraints arising because of an extended period of heavy rains that negatively affected mining and coal handling.

Supply was constrained further by a disruption to 600 MW of imports from Cahora Basa, in Mozambique, owing to a collapse of a transmission tower north of Pretoria.

However, Conradie insisted that Stage 6 had not been exceeded, with the balance of the cuts exceeding 6 000 MW arising from its extensive use of coal curtailment contracts with its large industrial customers, as well as interruptible supply contracts with the country’s smelters.

He confirmed, however, that a review of the loadshedding framework was under way to prepare for the prospect of higher stages of loadshedding in future.

It is understood that the new framework, which is still being drafted, could include up to 16 stages of loadshedding.

The current framework is outlined in a National Energy Regulator of South Africa document known as NRS048-9 and it is anticipated that the regulator will release a revised document for public comment in due course.

“At this stage, we don't foresee going to Stage 8, but we also need to be responsible and ensure that the schedules are clear if the situation forces us [to move beyond Stage 8] … so as to keep the demand and supply matched and to keep the system stable,” Conradie said during a briefing hosted to provide and update on the implementation of the Energy Action Plan.

“There's a workgroup working on the [new framework] which is not only Eskom, but also industry, reviewing and updating that document and, as I've alluded to earlier, the responsible thing is to make sure that this document caters for higher stages of loadshedding, and that those schedules are developed upfront so that we have a more systematic approach, if we require it.”