Bleak holidays ahead as Eskom output plummets to new lows

South Africans are set for a bleak, load-shedding-interrupted ‘festive’ season as Eskom’s generating output plummets to completely new lows.

At Tuesday evening’s peak, it wasn’t even able to output 23 000MW in total. This forced unprecedented overnight Stage 6 load shedding so that it could replenish the upper dams at its pumped storage schemes, which are being run as much as possible to keep the lights on.

Read: No Christmas present for Eskom

Remove around 2 000MW from the pumped storage and hydro schemes, 1 200MW of international imports and 918MW from Koeberg unit two, and it is clear just how poorly the coal fleet is operating currently.

Since 16 December, the utility’s coal power stations have not been able to generate more than 16 500MW of power.

This, from an installed base of 41 000MW, means that 60% of the fleet is offline, either for planned maintenance or due to breakdowns. (In October, when the country was facing daily power cuts, it was still able to generate above 18 000MW.)

No ‘December reprieve’ this year

Ordinarily, depressed demand as mines and factories shut for this period would offer some sort of reprieve from load shedding.

Instead, as Eskom’s generating performance deteriorates further – and with its diesel budget exhausted – the intensity of load shedding has had to increase over this period.

Eskom will likely try and avoid load shedding altogether on Christmas Day.

But this will require extensive use of its pumped storage schemes as well as diesel which it does not have the budget for. Perhaps Public Enterprises Minister Pravin Gordhan can ‘secure’ additional supplies from an inter-governmental ledger transfer.

Read:

Total peak generating supply has declined from the 27 000MW mark at the start of this month to under 23 000MW now. That’s equal to about four stages of load shedding.

Over the same time, demand is down by less than 2 500MW. You can see the problem. All this time, more units have broken down than have been returned to service.

Source: Eskom data

In its last update on Friday, Eskom said that 8 023MW of generation capacity was on planned maintenance, with a further 16 672MW offline due to breakdowns. This totals more than 24 500MW of capacity, from an installed base of 49 000MW.

In effect, half of Eskom’s capacity is offline (which is being exacerbated by the inability to use its diesel peaking plants at anywhere close to full capacity).

The steam generator unit replacement on Koeberg unit one has removed 900MW of stable generating capacity from the grid, meaning that supply will be even more constrained than usual until winter.

Maintenance

It is still scheduling more maintenance than typical over this period – around 8 000MW – but this figure is lower than originally planned. Eskom had hoped to take as much as 10 800MW offline over the festive season, but this has reduced to around 8 000MW due to scheduling issues with contractors and spares.

According to its most recent system status bulletin, Eskom’s planned maintenance level will be at roughly 6 000MW during January, then drop to around 5 500MW through February, and be at 4 668MW for March. (Eskom has not published a system status update for the last 10 days.)

Towards winter, this is forecast to decline to around 2 000MW. Factor in the 918MW offline from Koeberg for this period and is it clear that there is simply not enough head room for maintenance.

Read:

And once Koeberg unit one returns to service, Eskom has to take unit two offline for its steam generator unit replacement, deferred from earlier this year. That’s if both projects go according to plan, of course.

Even with this reduced level of maintenance, the outlook until winter is not great. Supply will be constrained until the end of March, following which near-constant load shedding is all but guaranteed until the end of the year.