No end in sight as load shedding nightmare worsens

Eskom was plunged into fresh crisis just before 18:00 on Tuesday when a generation unit each at Kendal and Lethabo power stations tripped. This necessitated the immediate implementation of Stage 4 load shedding from 18:00.

The utility had previously communicated that Stage 3 would be in effect until Thursday.

It provided no further information, save that it would “publish a full statement [on Wednesday] afternoon”. That it will take nearly a day to provide additional detail shows how dire the emergency at the utility is.

By Saturday, South Africans will have endured an entire month of continuous load shedding.

Already, as of midnight, Eskom has set a ‘record’ of over 640 hours of load shedding.

The only thing that has changed in this time has been the severity, which has ranged from Stage 2 to Stage 6.

Eskom skirted very close to Stage 7 during the peak at least once in the last month, on 19 September. Not only was the amount of load it was cutting far greater than 6 000MW – it was 6 770MW according to publicly available data – it also used its interruptible load supply mechanism to cut 447MW of supply to large industrial users. This equates to a total of 7 200MW of demand removed.

Various estimates have put the cost of load shedding to the economy at between R1.5 billion and R4 billion a day.

A back-of-the-matchbox calculation puts the impact of this latest ‘streak’ of nearly a month at over R70 billion.

Vulnerable

Executives at Eskom have repeatedly cautioned that the system remains unpredictable.

The trip at Lethabo is especially concerning as this power station has historically been one of the best-performing in the fleet. In the last financial year (to March), Lethabo was responsible for the fourth-lowest average megawatt loss across Eskom’s coal power stations.

The warning signs have been there since Saturday, however. Eskom’s coal fleet has not been able to generate more than 18 500MW since 08:00 on 1 October. It barely managed more than 18 000MW across the rest of Saturday, Sunday and Monday. The total coal fleet is theoretically able to generate 41 000MW but is currently not able to reach even 44% of this figure. Admittedly, it is doing more maintenance (around 7 000MW vs the ±5 000MW previously).

This level of maintenance is expected to remain elevated (and is planned to exceed 8 000MW in eight weeks) until around March next year.

Eskom was only able to maintain load shedding at the ‘reduced’ level of Stage 3 on Monday by burning diesel continuously at its open cycle gas turbines (OCGTs) from 03:00 until midnight. This contributed between 269MW and 1 971MW to the grid.

In other words, had its shipment of diesel still been unable to dock in the Cape, it would’ve had to implement Stage 4 load shedding during the day this week, and Stage 5 in the evening peak. Tuesday’s trips would’ve pushed us back to Stage 6.

The OCGTs operated by independent producers at Avon and Dedisa have had their own diesel supply issues. Until some marginal contribution on Monday (no more than 300MW), the last time they fed a single megawatt into the grid was on Thursday (and this was tiny).

Koeberg

At least Koeberg Unit 2 is back on the grid and stable, which provides 900MW of capacity – equivalent to one stage of load shedding. It finally returned to service last week much later than planned (the original target was June).

The nuclear plant is now back to full capacity, generating 1 800MW, although Unit 1 is scheduled to be taken offline soon.

During this long outage, its three steam generators will be replaced, and it is expected to be offline for at least eight months. Originally, this same work was supposed to be done on Unit 2 when it was shut down for refuelling in January. Instead, it was deferred to the end of next year as there were significant risks of delays in completing the work. A decision was made to rather rush the unit back online, albeit nearly four months late.

Read: South Africa’s nuclear sector has failed its test

Eskom management remains optimistic in the face of the current crisis, arguably laughably so.

In an interview with 702 last week, CEO Andre de Ruyter said the pressure on the grid was expected to ease this week with a number of “big units” coming back on line.

He told listeners that “the outlook is that during the course of next week we should be able to drop to Stage 2 … Hopefully by the weekend – if we don’t have any further issues – we should be able to emerge from load shedding.”

Instead, the situation has worsened.

And, so far, Eskom’s own worst-case scenario in its summer plan (27 days of load shedding in September and 22 in October) looks spot on.