CAPE TOWN – Eskom has confirmed that Unit 1 of the Koeberg Nuclear Power Station, currently offline for long-term maintenance, will return to service later than expected. Originally scheduled to be back online this month (July), the unit is now set to return by the end of August.
According to Eskom, the delay is due to additional maintenance needed on the new steam generators. During routine inspections — specifically a method called eddy current testing — defects were found in four tubes out of thousands. These defects were addressed immediately through an advanced automated repair process, carried out by international specialists and local teams.
“Our top priority is always the safety of our employees, the public and the environment,” said Bheki Nxumalo, Eskom’s Group Executive for Generation. “Carrying out these additional inspections and repairs to world-class standards, we are investing in the long-term reliability of Koeberg and South Africa’s energy future.”
Safety tests
Eskom also announced that all critical safety tests have been passed, including the legally required 10-year Integrated Leak Rate Test. This test involved pressurising the reactor building over 72 hours to ensure it remains structurally sound and airtight — a key safety requirement.
Despite the extended timeline, Eskom says this will not increase the risk of loadshedding. The national electricity grid is currently stable, and Koeberg Unit 2 remains fully operational, delivering close to 950MW with an Energy Availability Factor (EAF) of over 99%.
“The planned return of 2 500MW this winter is not dependent on Unit 1,” Eskom said. “Our latest Winter Outlook remains valid, and loadshedding will not be necessary if unplanned outages stay below 13 000MW.”
Once maintenance is completed, Unit 1 will be refuelled, tested, and reconnected to the grid. Eskom stressed that Koeberg’s two units are never taken offline at the same time, ensuring that the power station continues to contribute significantly to the country’s electricity needs.
