Eskom reports that it has received permission from the National Nuclear Regulator (NNR) to restart Koeberg Unit 1, but has once again missed a recently updated target date for grid synchronisation.

“The unit is in the process of being started up,” Eskom told Engineering News in response to an enquiry.

“We have permission from the NNR but are resolving some emergent issues on the secondary side of the plant,” it added, while indicating that the testing period would take about 14 days.

In a social media post, energy analyst Chris Yelland quoted Eskom chief nuclear officer Keith Featherstone as confirming that “Eskom is attending to problems on the turbine side of the nuclear plant”.

Eskom also told Engineering News that the Unit 2 outage would start only after Unit 1 was back in service.

Unit 1 was taken out of service for an extended maintenance outage on December 10 last year with an initial target of resuming production 180 days later in June.

The outage scope included the much-delayed replacement of the unit’s three steam generators, which is a prerequisite for Eskom’s application to the NNR for a licence to operate the unit for a further 20 years beyond its current 40-year licence expiry deadline of July 21, 2024.

By March, however, Eskom admitted that the June deadline was “no longer achievable”, and indicated that it would only resume production ahead of a similar long-duration outage at Unit 2, which was scheduled to undergo a similar outage in September.

From July onwards, further delays were then confirmed by both Electricity Minister Kgosientsho Ramokgopa and Eskom, leading to concerns that both units may be on outage simultaneously, placing even more strain on the loadshedding-prone network.

Eskom later outlined a November 3 date for grid synchronisation, which was later shifted to November 13.

The 14-day testing schedule outlined by Eskom implies that Unit 1 is now expected to return to service later this month, but no firm date has been provided by the utility.

Eskom also provided no update on the separation of the unit 1 and 2 licences, which the utility argues would reflect the fact that Unit 2 came into operation a year and a half later than Unit 1 in November 1985 and that its 40-year licence should thus be extended beyond July 21, 2024.

Securing the licence change request for Unit 2 has been identified as a key priority and risk for the operation of Koeberg for a further 20 years.