Eskom announced last Friday Koeberg Nuclear Power Station’s Unit 1 has reached a significant milestone when the mechanical work of the replacement of the steam generators was completed.
The unit is still set to be online in November, a mere six months later than expected.
TygerBurger reported last week (“Koeberg’s Unit 1 to remain offline”, 16 August) that Unit 1 has been offline since December 2022 for maintenance, refuelling and refurbishment. Unit 1 was expected to return to “full steam” in July this year, but will not be operational until November.
The power utility said in a statement the mechanical work is the most significant part of the scope and work involved complex activities. The completion thereof means Eskom is now proceeding with the outage activities that could not be performed in parallel with the replacement of the steam generators.
Immediately after the completion of the outage activities the reactor will be reloaded with fuel, enabling the return to service of the unit.
“The commissioning, including the necessary tests of the new steam generators, will take place while the unit is synchronised to the grid,” the statement reads. Given all the outstanding activities, Koeberg Unit 1 is planned to be commercially available on 3 November. Due to the deferment of the return of Unit 1, the outage of Unit 2 has been postponed to 7 November to ensure there is no simultaneous shutdown of both Koeberg units and can confirm that resources are ready to start with the first activities of Unit 2 outage.
Steam generator replacement
The replacement of the steam generators was a first of its kind complex nuclear project performed at Koeberg “and is the last major plant component out of the three… replaced on the unit as part of the Long-Term Operation (LTO) project,” the power utility says.
The other two components, namely the replacement of the refuelling water storage tanks and the reactor vessel closure heads, have been replaced in previous years on both units 1 and 2.
The steam generators is the last of the large components that Eskom deemed necessary for replacement in support of its application to operate the Koeberg units for another 20 years.
The new steam generators are more efficient and will produce an additional 27 MW while enabling Koeberg to continue generating electricity for years.
“Eskom would like to assure all stakeholders that the deferment of the Unit 1 outage does not negatively impact the licence application with the National Nuclear Regulator (NNR) to amend the Koeberg operating licence.
“Furthermore, as part of a continual improvement process, Eskom is analysing the causes of the delays on Unit 1 to ensure that they are not repeated during the upcoming steam generator replacement on Unit 2.”
