Eskom delays Koeberg 2 maintenance to avoid ‘total shutdown’

Power utility Eskom says that the outage of Unit 1 of the Koeberg Nuclear Power Station is almost at an end, and it will be synchronised to the national grid by the end of October 2023.

However, it will still take two weeks to ramp up the unit to full power, meaning it will only be back in full form by mid-November.

Because of this, the maintenance on Unit 2 of the power station has been pushed back to around mid-November as well, Eskom said. The unit was initially scheduled to go dark on 3 November.

“Over the past few days, many residents close to Koeberg Power Station might have noticed steam rising from the power station on some occasions. For the workers at Koeberg this is good news as it is an indication that the outage for Unit 1 is almost over,” Eskom said.

“Although it experienced some delays, the process of returning Unit 1 to service is intentionally
thorough, as it is essential to ensure all the safety systems are functioning correctly and that the unit
is ready to operate reliably for the duration of the upcoming cycle.

“Currently the water in the reactor circuit, which includes the three steam generators, has been increased to its operating pressure and temperature. The process required numerous tests of the safety systems, with more tests still to be performed before and after the start-up of the nuclear reaction.”

The three steam generators on Unit 2 are scheduled for replacement in the upcoming Unit 2 outage,
which will start once the Unit 1 commissioning is complete.

“Although this outage start date has been shifted to mid-November 2023, the Koeberg team together with the main contractor and their subcontractors are using the experience gained from the installation on Unit 1 to reduce the outage period required to replace the steam generators on Unit 2,” Eskom said.

Energy analyst Chris Yelland warned on Thursday that Koeberg risked a total shutdown due to the delays in bring unit 1 back online.

Because of the 10-day delay in returning unit 1, if Eskom hadn’t pushed back the shutting down of unit 2, the power station would have been completely dark for about a week.

The power utility’s latest announcement means this is unlikely to be the case.

Read: Total shutdown warning for one of South Africa’s most vital power stations