South African power utility Eskom has decided to defer the steam generator replacement programme at unit 2 of its Koeberg nuclear power plant.
“Unit 2 of the Koeberg Nuclear Power Station was shut down on 18 January 2022 for a regular refuelling and maintenance outage, the scope of which included the replacement of the three Steam Generators on the unit," Eskom said 4 March.
"On the Steam Generator Replacement (SGR) work, prior to the start of any irreversible work, Eskom and the main contractor Framatome performed a final review to ensure that the SGR work would be completed at the expected quality levels and in accordance with the outage schedule. The review concluded there is a high likelihood of the unit being returned to the grid later than currently planned," Eskom said.
"Due to the potential severe impact of returning this unit later than June 2022 as initially planned, the decision has been made to defer the SGR to the next outage on this unit, planned for August 2023.”
It added: “This is to avoid the risk of impacting electricity supply during the high demand winter period as the earlier return of Koeberg 2 to service will assist in mitigating the risk of loadshedding. This deferral does not impact the safe operation of the Koeberg Nuclear Power Plant or on Eskom’s life extension plan for Koeberg, which requires the replacement of the steam generators on both units."
Eskom said that based on the condition of the original steam generators, the deferral of the SGR modification does not impact the safe operation of Koeberg 2, an 920MWe pressurised water reactor. The original steam generators will undergo a full series of routine inspections and tests to ensure that their integrity is maintained for the next operating cycle.
To date fuel has been unloaded, and the majority of work planned in the early part of the outage has progressed according to schedule.The reactor is expected to be returned to service during June 2022, "to help reduce the pressure on the rest of the generation capacity and to limit the impact of loadshedding during the winter period," Eskom said.
It added that the steam generator replacement project at Koeberg 1 will proceed as planned, starting in September 2022.
The two reactors at Koeberg were built by Framatome, and began commercial operation in 1984 and 1985. They generate about 5% of the South Africa’s electricity.
Photo: South Africa's Koeberg nuclear power plant (Credit: Eskom)
