Eskom has announced the deferral of a project to replace three steam generators at Koeberg Unit 2 to August 2023 following a review, conducted together with Framatome, which indicated that the replacements were unlikely to be completed within the six-month timeframe allocated for the project.

COO Jan Oberholzer said that certain facilities, including the completion of the building that would house the radioactive steam generators being removed, were deemed to be not fully in place to ensure that the replacement could be completed to expected quality and schedule parameters.

The decision to defer, he added during a briefing on Friday, was made late on Thursday, March 3 and against the backdrop of ongoing supply pressures, which continued to pose a load-shedding risk.

The decision was, thus, based largely on a desire to ensure that the unit’s 920 MW were available for at least part of the high-demand winter months.

The six-month maintenance schedule had not been shortened as a result of the deferral, however, as several other long-duration maintenance projects were scheduled to take place in parallel and were proceeding, including the replacement of the reactor pressure vessel head.

Unit 2 was shut for refuelling and an extended maintenance – which included the steam generator replacement programme – on January 18 and would be returned to service in June.

Chief nuclear officer Riedewaan Bakardien reported that Eskom planned to proceed with the replacement of Unit 1’s three steam generators in September, when the next batch of replacement units was scheduled to begin arriving in South Africa.

Framatome had indicated to Eskom that the first replacement steam generator for Unit 1 would be delivered in September, with the other two arriving in October and/or November.

The much-delayed R20-billion replacement of the six steam generators is core to Eskom’s decision to extend the life of the Koeberg station beyond the 2024 and 2025 current operating life of the two respective units.

The utility has initiated a process to secure a life extension to 2044 and 2045 respectively and the National Nuclear Regulator (NNR) received an application from Eskom on May 10, 2021, for an extension of Koeberg’s operating life.

The NNR expected to receive Koeberg’s Long Term Operations, or LTO, application safety case by July 2022, after which an adjudication would take place, along with public consultations.

Several stakeholders have raised objections to the life extension and have questioned whether it is prudent for Eskom to be proceeding with life-extension investments in the absence of a licence.

Bakardien said that Eskom understood what was required for securing life-extension approval, including the need to replace the six steam generators.

Oberholzer indicated that he had requested Framatome to provide him with a detailed outline of what was required for Koeberg to be fully ready for the next outages, as he did not want the life-extension project jeopardised by delays.

“Although there is time, up until the middle of 2024 and 2025, for [securing] the life extension licence, I would like to make 100% sure that we don't push everything right until the end,” Oberholzer said.

The cost implications of the deferral were yet to be determined.