Stage 8 load shedding warning
South Africa’s sudden return to stage 6 load shedding after about a month of day-time suspensions of the rolling blackouts is not really a surprise, say energy experts – and the risk of things escalating remains a possibility.
Eskom was forced to return to stage 6 load shedding this week after inclement weather caused a spike in demand for power.
A major cold front swept the nation at the weekend, leading to below-zero temperatures in part of the country and even lead to the rare occurrence of snowfall in Gauteng.
This, in turn, caused a spike in user power demand, from around 30,000MW before the freeze to around 34,000MW after – equivalent to an additional four stages of load shedding.
At the same time, Eskom’s generation capacity has also deteriorated from a relatively consistent 28,000MW to under 27,000MW, adding further pressure to the grid.
In effect, Eskom’s generation shortfall went from around 2,000MW to 7,000MW overnight, necessitating the return to stage 6 load shedding.
On Wednesday (12 June), Eskom said that 6,432MW was shed from the grid. Technically, this is already equivalent to stage 7 load shedding, but the utility is using other mitigation efforts – such as load curtailment, load limiting, etc – to keep national schedules at stage 6.
However, this does not rule out the possibility of outages escalating.
Speaking to the Daily Maverick and Mail & Guardian this week, Eskom noted that stage 8 load shedding or worse is still a possibility, though it remains unlikely. It all depends on supply (keeping units up and running) and demand from users.
The utility also needs to refill its reserves, which adds more variables to the equation.
Worst-case scenario
In its pre-winter system outlook, Eskom highlighted three main scenarios for the winter months.
The best-case scenario is that Eskom can keep generation up and unplanned outages – or breakdowns – below 15,000MW. This would allow the utility to keep load shedding between stage 3 and 5 for the winter period.
The actual outcome from Eskom – at least until now – has actually been better than this. The group managed to keep outages at or below 15,000MW, and the utility was able to eventually suspend load shedding for most of the day (usually between midnight at 16h00), only moving to stage 3 in the evenings.
Eskom managed to achieve this thanks to much lower demand from energy users. The group had anticipated winter demand to exceed 33,000MW. Coming in as low as 28,000MW in June, the country spared itself five stages of load shedding against the forecast.
So good was Eskom’s performance in June that electricity minister Kgosientsho Ramokgopa confidently declared on Sunday (9 July) that the country was riding the best-case scenario this winter.
According to Eskom, the worst-case scenario would be if unplanned outages pushed beyond 18,000MW and demand exceeded 33,000MW.
With demand now at 34,000MW, the country is squarely within this forecast on the demand-side, and the escalation of load shedding is now contingent on Eskom containing outages and managing supply until demand subsides.
Because Eskom’s grid is notoriously volatile and unpredictable, the hopes of keeping out of higher stages of load shedding are riddled with uncertainty.
Despite assurances from Ramokgopa that the system is improving, Eskom’s energy availability factor (EAF) is yet to breach 60% (only being rounded up to 60% in press briefings for a positive spin).
EAF is currently sitting at around 58%.
Read: South Africa is living the ‘best-case scenario’ for load shedding