Project marks first time this type of facility has been defuelled
The first of the UK’s seven advanced gas-cooled reactor (AGR) nuclear power stations has been emptied of fuel, marking a significant milestone in the country’s decommissioning process.
Station owner and operator EDF said on 24 April the defuelling of the Hunterston B nuclear power station on the west coast of Scotland had been completed on time and on budget.
Hunterston B has two AGR units, Hunterston B-1 and Hunterston B-2, that were permanently shut down in 2021 and 2022 respectively. Hunterston B-1 had a net capacity of 490 MW and Hunterston B-2 of 495 MW. They began commercial operation in 1976 and 1977.
Defuelling of reactor B-1 started in May 2022 and took 16 months. Defuelling of reactor B-2 started in November 2023 and took 14 months meaning both reactors were defuelled in just over 2.5 years with improved performance between reactors.
EDF said the defuelling would pave the way for the transfer of the site and 250 staff from the French power company to the UK Nuclear Decommissioning Authority (NDA) next April for its subsidiary Nuclear Restoration Services to carry out the rest of the decommissioning. The NDA is a government body established to clean up the UK’s earliest nuclear sites.
Andy Dalling, station manager at Hunterston B, said the process was “on time and to budget and marked the first time this type of station has been defuelled”.
“That means lessons we’ve learned over the past three years will be applied to the rest of the fleet,” he added.
EDF said the defuelling used funds from the Nuclear Liabilities Fund, a ring-fenced £20.6bn (€24bn, $27bn) fund set up in 1996 specifically to pay for the decommissioning of the nuclear fleet.
The spent fuel from Hunterston has been packaged into 350 large flasks, which will be stored by the NDA at the Sellafield nuclear site in Cumbria for at least 50 years until a longer-term underground spent fuel repository has been built.
Background: Shutdowns And New Build
EDF owns and operates eight nuclear power stations in the UK. Three of them – Hunterston B, Hinkley Point B and Dungeness B – are in decommissioning and five are generating. The five that are generating have nine plants between them. They are: Torness, Hartlepool A, Heysham A, Heysham B and Sizewell B.
Seven of the stations have AGR plants, which differ from newer nuclear plants that use water for cooling. Sizewell B, a newer facility that began commercial operation in 1995, has a single pressurised water reactor (PWR).
Since 2000, the UK has seen permanent reactor shutdowns at Bradwell, Calder Hall, Hinkley Point A, Hinkley Point B, Hunterston, Oldbury, Sizewell, Chapelcross, Dungeness and Wylfa.
The last unit to go offline was Hinkley Point B-1 in August 2022.
The only commercial nuclear plants under construction in the UK are two EPR units at Hinkley Point C, although there are plans for two new units at Sizewell C.
Planned shutdowns could leave the UK with just Sizewell B online by 2030.
EDF has said Hinkley Point C is projected to become operational sometime between 2029 and 2031, with a “base case scenario” of 2030 for Unit 1.
EDF said both reactors at Hunterston were defuelled in just over 2.5 years with improved performance between reactors. Courtesy EDF Energy.
