Eskom’s load shedding outlook looks very Grim for SA in 2023

Power utility Eskom has presented its system status and outlook to the joint portfolio committee on public enterprises and mineral resources and energy, outlining what it expects in terms of power capacity and maintenance over the next year.

The group noted that from 1 January to 29 August 2022, there have been 91 days of load shedding, with 18 days of load curtailment – load reduction obtained from customers who are able to reduce demand on instruction – at stage 1 and stage 2 and two days at stage 3.

The main causes of these power disruptions are generally attributed to a shortage of generation; increased unplanned unavailability; limited fuel availability at peaking stations; the need to conserve and replenish depleted emergency resources; and poor coal and compromised emissions performance, Eskom said.

Eskom laid out its plan to maintain its network over the summer months, taking into account available generation capacity, demand, planned outages and making room for unplanned outages.

The state firm stressed that its plan is “full” – meaning that there is very little room for error. “All reliability maintenance required in the 12-month planning period has been accommodated in the plan. This has resulted in a ‘full’ plan with little room to move, extend or add outages,” Eskom said.

“The plan requires OCGT usage over weekdays and low diesel usage on some weekends. The failure of Medupi 4 has increased the dependency on diesel generation to manage the power system,” it said.

The plan was ‘stress tested’ in three scenarios, each with various levels of outages, use of gas turbines, and different levels of load shedding.

In general, Eskom’s base outlook – best case scenario – is that unplanned outages can be kept at 13,000MW, with minimal use of gas to cover any shortfall. In this scenario, load shedding, if needed, will be kept to stage 1, and only implemented over 24 days.

Historically, the base case for outages was 10,000MW. This has been increased because of past performance.

In the middle road profile – where unplanned outages expand to 14,500MW – load shedding at stage 2 becomes frequent. In this scenario, Eskom expects load shedding every month, up to 20 days.

In the ‘worst case scenario – where unplanned outages exceed 16,000MW – load shedding at stage 3 and on occasion stage 4, is almost always in effect, and billions of rands are spent to generate power to cover the shortfall.

Eskom warned that the plan is extremely tight, and any significant outage slips will have a severe knock-on effect. It also does not cater to any additional problems that could arise from industrial action or other protests.

Illegal strikes at Eskom power stations earlier in the year lead to stage 6 load shedding, putting the country in the dark for five weeks as a result.

Uncertain times

The power utility stressed that the plan and the system as a whole is plagued by uncertainty.

There is typically a 4,000MW variance in the Unplanned Capacity Load Factor (UCLF), which cannot be predicted, it said – equivalent to stage 4 load shedding.

“In practical terms, it mostly means we operate in the range of having 2,000 MW of reserve to needing stage 2 load shedding to create sufficient reserves,” it said.

It added that the success of the plan also relies on sufficient diesel to support the power system during periods of high UCLF. Without sufficient diesel to power the 3,000MW of OCGT, three additional stages of load shedding could be added to the scenarios, it said.

Eskom said that history has shown that it is not possible to use more than R2.4 billion worth of diesel in a month due to the physical limitations of moving the diesel to the OCGT stations. Where the plan shows a diesel usage greater than this, additional stages of load shedding should be expected, it said.

These periods are highlighted in red below:

Eskom said that it does anticipate adding more capacity to the grid over the next three years (36 months) which will greatly reduce the risk of load shedding.

This includes new generation capacity from independent power producers (13,700MW), new builds at Eskom (2,400MW), managing demand (1,450MW), and optimizing existing plant performance (5,600MW). However, this is also dependent on market response and regulatory processes, it said.

Source: Bussinestech