Good news for Eskom’s Koeberg nuclear power station

Eskom announced on Friday that Koeberg Unit 1’s steam generators had been replaced and should be synchronised to the grid by the end of October 2023.

“Over the past few days, many residents close to Koeberg power station might have noticed steam rising from the power station on some occasions,” the power utility said.

“For the workers at Koeberg, this is good news as it is an indication that the outage for Unit 1 is almost over.”

Once they are synchronised, the unit will start supplying electricity to the national grid.

Its output will be ramped up to full power over two weeks while commissioning tests are performed.

“This marks another milestone on Eskom’s Generation Operational Recovery Plan, which is aimed at sustainably improving generation performance by improving the energy availability factor to an average of 65% by March 2024,” Eskom stated.

Eskom said that although the maintenance to Koeberg Unit 1 experienced some delays, the process is intentionally thorough.

This is to ensure that 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 (155 bar and 300 degrees Celsius),” said Eskom.

“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.”

Eskom said completion of the commissioning tests will end a long but safe steam generator replacement journey and signal the return of Unit 1 to commercial operation.

“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,” Eskom said.

“Although this outage start date has been shifted to mid-November 2023, the Koeberg team together with the main contractor and their sub-contractors 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 replacing the steam generators was identified as being a prerequisite for safely extending the station’s original licensed operating period of 40 years (beyond 2024).

The state-owned power utility submitted the licence extension application to the National Nuclear Regulator (NNR).

“The completion of this long and challenging outage on Unit 1 through the commitment, sacrifice and hard work of all the Eskom employees, contractors, partners, and suppliers is a huge milestone in the process of extending the life of Koeberg and a positive development in the execution of Eskom’s Generation Operational Recovery Programme,” it continued.

“Hopefully, should the NNR award the licences to Koeberg to operate beyond 2024, the station will continue to operate safely and reliably for another 20 years, as it has been the case for the last 39 years. This is recently demonstrated by Unit 2 good performance while Unit 1 was on long outage.”