Industry experts have been queuing up over the weekend to proclaim – possibly prematurely – the death-knell of the British nuclear industry.
This follows the un-planned shutdown of the Scots nuclear reactor-3 at Hunterston power station after the discovery of ‘key cracks’ on the graphite blocks used to provide nuclear insulation ‘cladding’.
Britain’s Office for Nuclear Regulation was informed in March about root cracks found during planned inspections of the graphite bricks in the core of Reactor 3 at Hunterston by its owner, the French nuclear giant EDF.
The reactor has been offline since March and was due to come back online this month, but EDF Energy has now extended the off-line repairs that will keep the plant from generating electricity until at least December this year.
Hunterston-B station director Colin Weir said that the un-scheduled shut down will reduce the station’s output by 40% – about 3 terawatt hours – this year.
EDF said that the prospect of more of its fleet of ageing nuclear reactors having a sustained outage is highly unlikely, but experts said it would pose a significant challenge to power supplies if they did.
But Peter Atherton, an analyst at the consultancy Cornwall Insight, said: “Let’s say worst-case scenario they found a big graphite core problem and Hunterston never comes back on.
“That would be a big hole in the plan [for electricity supplies]. The gas-fired power stations, we’ve probably got enough of them, but it would be pretty tight. It would also be a knock-back to carbon targets. You could build more windfarms, but that would take time.”
The Hunterston shutdown is the longest yet over the graphite issue, which EDF calls a “unique challenge”, and company presentations concede the cracking “will probably limit the lifetime for the current generation of AGRs”.
Last week, EDF said it would extend the shutdown at Hunterston to November 2019 to allow for additional safety checks after it discovered more new cracks. But the operator insists it will ultimately be able to restart the reactor — something it can only do with the ONR’s permission.
But independent nuclear engineer John Large commented: “I’m absolutely positive they won’t be able to do that.
“EDF can’t do anything physically to resolve the situation. The bricks were never designed to be replaced. In fact, it’s entirely inaccessible inside the reactor’s core.”
Edinburgh-based nuclear consultant Peter Roche, added: “Hunterston is now 42 years old – and this must surely be the end <of the road> for Reactor-3.
“We are gambling with public safety by extending the lives of old nuclear reactors.”
Hunterston was first scheduled to close down in 2012, but its operating life has since been expected. It is now formally due to close permanently in 2023.
8 May 2018