Scottish nuclear plant emptied of fuel as UK winds down ageing gas-cooled reactors

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04-05-2025

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The first of the UK's seven advanced gas-cooled reactor nuclear power stations has been emptied of fuel, kick-starting a decommissioning process that will cost at least £27bn in total and take almost a century.
EDF said on Thursday it had defuelled Hunterston B, on the west coast of Scotland, paving the way for the transfer of the site and 250 staff from the French power company to the UK Nuclear Decommissioning Authority next April.
The site provided most of Scotland's energy for more than 40 years from its launch in 1976 until its final closure in 2022.
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 owns seven advanced gas-cooled reactors (AGRs) plants in the UK, which were built between the 1960s and 1980s and differ from newer nuclear plants that use water for cooling. Just four are still operating.
The uranium fuel 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 facility has been built.
Although the process took just three years and £400mn, it will take almost a century to eradicate the radiation from the land and buildings, EDF has said.
The decommissioning of the seven AGRs is separate to a much wider £105bn decommissioning programme, which will cover an additional 17 closed nuclear sites over the next 120 years, according to the NDA.
The closures will leave the UK with just one nuclear power plant still running by 2030 — Sizewell B in Suffolk, which is also managed by EDF and uses a pressurised water reactor.
The NDA said it was 'acutely aware of the costs associated with delivering our mission'.
The cost of decommissioning nuclear power plants is under scrutiny as the UK presses ahead with new nuclear projects, including the £40bn Sizewell C, which is expected to get government go-ahead this spring, and the £46bn Hinkley Point C, which is still under construction and will open by 2030 at the earliest.
EDF has a 72.6 per cent stake in Hinkley Point C and is tipped to take a 10- 20 per cent stake in Sizewell C, though discussions with the government are ongoing. The decommissioning on both Hinkley and Sizewell C is expected to be shorter, with separate funds planned to cover the costs.
Steve Thomas, emeritus professor of energy policy at Greenwich university, said the cost of decommissioning should be taken into account when the government decided on new nuclear plants as 'no scheme can be guaranteed to meet a cost more than a century into the future'.
Although EDF has owned Hunterston B and the seven other AGR nuclear plants since 2009, the cost of decommissioning is being paid for through the ringfenced Nuclear Liabilities Fund (NLF), which was set up in 1996 after privatisation and is valued at £20.6bn.
Decommissioning costs have soared over the past three decades, with the fund requiring cash injections from the Treasury, including £5bn in July 2020 and a further £5.6bn in March 2022, according to the NLF.
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The last of the AGR reactors is expected to be defuelled and transferred to the NDA by 2035, though they may receive further life extensions. Hunterston worked for 20 years more than was originally intended.
Although controversial, nuclear power complements the intermittency of renewable energy such as wind and solar power. But there are concerns that the UK has no permanent and safe facility for storing the waste.
Most of the waste is stored at Sellafield, where 140 tonnes of plutonium is held in decaying containers and ageing buildings, though in line with regulatory requirements.
The government is seeking a site where treated high-hazard waste could be safely disposed of underground with three potential locations in Cumbria and Lincolnshire identified.