Eskom’s Winter Challenge: Can Unprecedented Load Shedding Be Avoided?

South Africa’s power utility, Eskom, is in a race against time to increase its energy output in order to avoid unprecedented load shedding during the colder months. As winter approaches, South Africans brace for the possibility of facing severe load shedding, with Eskom’s coal fleet struggling to reach above 50% output.

Load Shedding: An Unwanted Reality

• Eskom chair Mpho Makwana warned in January that Stage 2 and Stage 3 load shedding would become a near-permanent fixture over the next two years.
• The reality has been more severe, with frequent instances of Stage 4 and even occasional Stage 5 and 6 load shedding.

Eskom’s Recovery Plan: Can They Reach Their Targets?

• Eskom’s own target of increasing generation from six priority power stations by 1,862MW by the end of the month will not be met.
• They aim to recover 6,274MW of total capacity from Tutuka, Kendal, Duvha, Majuba, and Matla over the next two years, including the return of Medupi Unit 4 and the completion of Kusile units 5 and 6.
• Recovery of this generation capacity would bring the energy availability factor (EAF) to 59% by the end of the financial year (30 March 2023). Currently, the average EAF is 56.6%.

Factors Affecting Energy Availability

1. Koeberg’s current contribution is at 50%.
2. Damaged towers have reduced power imports from Cahora Bassa.
3. Pumped storage schemes and open cycle gas turbines (OCGTs) also contribute to energy availability.

The Challenge: Meeting Peak Demand in Winter

• Eskom must generate at least 3,000MW more than the current ±30,000MW to meet peak demand in winter.
• Despite downward adjustments in demand forecasts for June and July, Eskom still needs to increase capacity by 3,500MW to 4,000MW.

How Can Eskom Plug the Shortfall?

1. Imports from Mozambique should be running at full capacity.
2. Allocate funds to burn diesel at OCGTs.
3. Improve the performance of coal power stations.
4. Cut maintenance to a minimum during winter, potentially gaining 2,000MW of additional capacity.

Recent Improvements

• Six coal power stations achieved an EAF of 70% in the past week.
• Stations like Lethabo, Matimba, and Medupi are already top-performing, while Duvha and Matla are targeted for turnarounds.
• Camden has shown mixed performance.

The Risks: Dipping Capacity and Koeberg’s Return

• If capacity dips to 45%, Stage 8 load shedding for June peaks becomes almost certain.
• Koeberg Unit 1’s return from a steam generator replacement outage in June is crucial, as it provides 900MW of stable output. However, work outages at nuclear plants seldom run on time.

With Eskom facing numerous challenges, it’s clear that the company must work diligently to increase its energy output and avoid further disruptions for South Africans. The severity of load shedding this winter will largely depend on the performance of Eskom’s coal power stations and their ability to meet the increased demand during the colder months.