Eskom’s coal-fired power station breakdown lie

Electricity minister Kgosientsho Ramokgopa

Eskom’s latest energy availability factor (EAF) data reveals that mismanagement, corruption, poor maintenance, and sabotage caused most breakdowns, not the ageing power fleet.

For many years, Eskom has been telling South Africans that its ageing coal-fired power station fleet is the main reason for the high breakdown levels and load-shedding.

However, an analysis of Eskom’s latest EAF of its power plants reveals that breakdowns do not correspond with age.

The EAF shows the percentage of time the power station was available for use when it was needed. It is a core measure of performance.

Over the last six years, Eskom’s EAF plummeted from around 80% to below 55%, which is the main cause of load-shedding.

Although a power station’s EAF is expected to decline with age, it is nowhere as drastic as what was seen at Eskom since 2017. 

Eskom’s latest EAF date, shared by electricity minister Dr Kgosientso Ramokgopa, shows that age is not a big factor in breakdowns and poor performance.

  • Three of the newest power stations – Kusile (37%), Majuba (48%), and Kendal (47%) – have some of the worst EAF of all plants in Eskom’s fleet.
  • Eskom’s oldest power stations – Camden (70%) and Grootvlei (90%) – have some of the best EAF of all plants in Eskom’s fleet.

The EAF data further showed that Tutuka (26%), rife with corruption and mismanagement, has a much worse EAF than other power stations of the same age, like Letabo (74%) and Matimba (75%).

It clearly illustrates that age is not significant in EAF but rather how well the power station is managed.

Therefore, Eskom and other stakeholders should stop using the convenient excuse of old power plants for poor performance.

Instead, they should focus on improving performance through better management, rooting out corruption, and stopping sabotage.

The chart below shows the EAF of Eskom’s coal-fired power plants, ordered from newest to oldest. It reveals no strong correlation between age and performance.

South Africa versus United States

Another analysis by Daily Investor also showed that the age of a power station does not automatically result in higher breakdown rates and a lower EAF.

We compared the performance of Eskom’s Tutuka and Duvha power stations with two US-based coal power stations – Wansley and Scherer. These power stations are roughly the same age.

  • The Duvah power station was first commissioned in 1980, with the final unit completed in 1984.
  • The Wansley power plant in Georgia was first commissioned in 1976.
  • Tutuka was first commissioned in 1985, with the final unit going online in 1990.
  • The Scherer power plant was commissioned in 1982 and is of a similar age to Tutuka.

If Eskom’s claim of ageing infrastructure causing a significant deterioration in performance is true, the US and South African power stations should show similar trends.

A significant difference in performance points to other factors, like poor maintenance, mismanagement, and a lack of skills.

From 2009 to 2021, Eskom’s Tutuka and Duvha had an average EAF of 64% and 56%, respectively. It means that since 2009 they were only available for 64% and 56% of the time they were needed.

In 2021, Tutuka and Duvha had average EAF of 37% and 44%, respectively. It is expected to be much worse in 2022.

Wansley and Scherer, in comparison, had an average EAF of 90% and 89%, respectively, over the same period. They were, therefore, available for 90% and 89% of the time they were needed.

An interesting observation is that Scherer and Wansley had an upward trend in their EAF figures as time progressed.

The large differential suggests that ageing infrastructure can still be reliable. With regular maintenance and using the latest technology, their performance can even improve.

The chart below shows the performance over time of the two power stations in the United States compared with Eskom’s Tutuka and Duvha.


Top JSE indices