Koeberg’s Second Steam Generator Overhaul on Track for Quick Turnaround

Koeberg nuclear power station, standing as a cornerstone in South Africa's energy landscape, is currently undergoing critical maintenance work aimed at extending its operational life. Eskom, the state-owned electricity utility, has provided an upbeat update on the work on the station's unit two generator. The generator was taken offline in December 2023 for a replacement of its steam generator, a complex procedure that is now unfolding more rapidly than anticipated.

This maintenance job is more than periodic upkeep. It is a significant step in ensuring Koeberg's ability to continue its contributions to the grid. The 980MW unit, which powers swathes of the country, must have its steam generators replaced to meet a key condition for the extension of its life span beyond the original 40-year design period. Eskom is aiming for a seamless return to service by the end of September 2024, well within the tight deadlines set to achieve the station's operational licence extension.

This swift progress is underpinned by hard-earned experience. Electricity minister Kgosientsho Ramokgopa pointed out that the learnings from the previous delays encountered during the maintenance on unit one, which took around 11 months, have informed the current approach. Decisive action and a focused understanding of past mistakes are driving the team towards a speedier, more efficient completion of the overhaul.

Once unit two rejoins the grid, both units will contribute over 1,800MW of electricity, a notable input although the units will not run concurrently for a couple of years due to planned further outages. These are necessary for another crucial assessment phase – the evaluation of the concrete containment structures which are showing signs of wear.

Eskom's transparent communication regarding these developments bolsters confidence in the measures being taken to secure South Africa's energy future. The National Nuclear Regulator (NNR) plays a pivotal role in this process, holding the key to the operational licence renewal. Eskom's application for an additional 20-year extension remains under the scrutiny of the NNR, with the regulator's decision hinging on the successful completion of these maintenance activities.

The regulator's programme manager, Peter Bester, outlined the ongoing need for outages even after the current work is completed, projecting a landscape where dual operations of the units are rare in the near future. Nevertheless, with the prompt progress on unit two and the return of unit one to service, Eskom shows signs of emerging from a challenging period with reinforced vigour. Chris Yelland, managing director at EE Business Intelligence, indicates caution towards pending work, but the current trajectory provides hope for a positive outcome.

In South Africa, where the stability and growth of the economy are closely tied to the reliability of power supply, the steps being taken at Koeberg power station have implications that reach far and wide. The timely and successful completion of these maintenance operations may not only stave off the risk of an operating licence denial but also anchor a more secure and sustainable energy production system for the years to come.