• The Koeberg nuclear power station is facing repairs to its two generating units, Eskom’s best power producers, which will remove them from the grid for a total of 28 months between 2022 and 2025.
• Unit 1 is expected to return to service in August, after which Unit 2 will be taken offline for its own repairs until April 2024. Unit 1 will then undergo a further 200 days of maintenance until February 2025.
• Each unit produces energy comparable to a single stage of loadshedding and their extended outages are estimated cost the economy around R500 billion.

The Koeberg nuclear power station Unit 1 is expected to be put offline again, and it hasn’t even been returned to service yet. The generating unit, one of two, at Africa’s only nuclear power station was taken offline initially in December last year to face a battery of repairs.

These repairs are to ensure that the station can last another 20 years and adhere to nuclear energy safety regulations. After repairs of Unit 1 are completed, Unit 2 will also be brought offline to undergo its own maintenance.

Each of the Koeberg generating units, the largest on the continent, produce nearly 1 000MW of electricity, comparable to a single stage of loadshedding.

According to a new Daily Maverick op-ed from South African energy expert Chris Yelland, Eskom is planning a further 200-day shutdown of Koeberg Unit 1. This time to begin on 24th July 2024.

Unit 2 is now expected to go offline for repairs in October 2023 for completion in April 2024. This means that South Africans will only enjoy three months of both units adding power to the grid before Unit 1 is taken offline again in the winter of 2024. That is of course if Unit 2 doesn’t face any delays itself.

Having both units online means that Stage 6 becomes Stage 4 instead, and so on. As the energy crisis continues to weigh heavily on South Africa, repairs at Koeberg between 2022 to 2025 would have removed its capacity from the grid for 28 months, with an estimated cost on the economy of some R500 billion, says Yelland.

Koeberg 1 was initially expected to be offline for six months from the initial December period, but delays in its repairs added another 45 days to that timeline.

If all goes to plan with repairs, South Africans can expect Unit 1 to be brought online in August, near the end of winter. Eskom executives and even the Minister of Electricity are forecasting higher stages of outages during the colder months as the use of heaters and similar drives up demand.

According to Yelland, the latest planned shutdown of Unit 1 means that it will only be returned to service again in mid-February 2025. Eskom’s plan for the generating unit suggests that it may even be delayed past this deadline.

What is the need for another 200-day outage of Unit 1 after nearly eight months of repairs? The country’s power utility hasn’t made this apparent but did indicate that it is “…planning to perform identified maintenance and inspection activities including, for example, the routine 10-yearly containment integrated leak rate test.”

Eskom also wants to give the independent National Nuclear Regulator (NNR) enough time to decide if the unit is fit to receive its 20-year safety license extension.

The current license will expire on 21st July 2024, three days before the unit is to be taken offline again.

Regulatory processes are such that Eskom cannot introduce fuel into the Unit 1 reactor unless it has this license. So it needs to be licensed first, and then the unit can start generating electricity again.

“It would appear that Koeberg Unit 1 will only resume operation after its licence is extended by the NNR, and after a further 200-day outage of Koeberg Unit 1 starting on 24 July 2024 and ending in mid-February 2025,” writes Yelland.

In order to reduce delays in energy generation, Eskom wants to license both of Koeberg’s units individually, with Unit 1’s license expiring in July 2024, and Unit 2’s in July 2025.

The NNR has yet to agree on this plan but Yelland says it may be possible as both units were initially commissioned and began operating a year apart in 1984 and 1985 respectively.

Eskom is expected to spend R22 billion on the maintenance of both units when all is said and done.

[Image – Eskom]
[Source – Daily Maverick]