Eskom has received permission to run Koeberg Power Station’s unit 1 reactor, but according to University of Pretoria professor David Walwyn, it won’t do much to address South Africa’s energy crisis.

While the unit’s return is a significant milestone for Eskom, it will only add 920MW to the grid at full capacity, which Walwyn says will temporarily reduce load-shedding by approximately one stage.

“Unit 1 has an output of about 1GW, and we need altogether about 30GW in the system. For every gigawatt that we are missing, that’s one stage of load-shedding,” Walwyn said in an interview with Newzroom Afrika.

“So when we get unit 1 back, that will be one stage of load-shedding less. At the moment, we have [stages] 2 to 3, we would be at [stages] 1 to 2 if unit 1 was fully operational.”

Moreover, this benefit will only be in effect temporarily until Unit 2 is taken offline to have its steam generators replaced.

“The capacity that we’ve been relying on from Koeberg Unit 2 will now be replaced by Unit 1, and Unit 2 will be taken offline,” said Walwyn.

Eskom recently told MyBroadband that the replaced steam generators were operating correctly. However, Walwyn believes there is another critical check that should take place before its synchronisation.

“There’s also another very important check that needs to be made at Koeberg — and that is the check of the integrity of the concrete shell that encases the building, which is there to protect us from the worst of a nuclear accident,” said Walwyn.

“God forbid that there would be a nuclear accident, but that concrete shell around Koeberg is a first line of defence against anything that might happen.”

“There are reports that the casing has cracks in it and may need to be significantly reconstructed,” he added.

Walwyn said Eskom could technically apply for the extension of Koeberg unit 1’s operating licence once it has synchronised to the grid rather than waiting for the refurbishment of unit 2 to be completed.