A new generation of nuclear power plants could burn 100 tonnes of surplus weapons-grade plutonium as a good way of keeping it away from terrorists, according to scientists working for the European Union.
Containers holding used nuclear fuel being stored under water for up to five years to allow the fuel to cool down, before the uranium and plutonium is reprocessed. Photograph: Don McPhee
Most of Britain's weapons-grade plutonium is held in bunkers at the Sellafield complex in Cumbria, behind three perimeters of razor wire patrolled 24 hours a day by armed guards in one of the most closely guarded compounds in Europe. The material comes from reprocessing spent fuel at Sellafield over the past 50 years.
The plutonium was used initially for bomb making, then for feeding a now-abandoned European nuclear fast breeder reactor programme. But it has sat around unused for years, becoming a huge political embarrassment as well as a potential target for extremists.
The status of plutonium has shifted from its initial description by the United Kingdom Atomic Energy Authority as "100 times more valuable than gold" to the Royal Society's report this September that described it as a stockpile of highly dangerous toxic material that constitutes a serious terrorist threat.
Whatever solution the UK government adopts, the stockpile will cost billions of pounds to process and make safe since the material is held in its most dangerous form as an oxide power. One particle of the powder in the lungs can be a death sentence.
The idea that Britain could burn off the plutonium has been suggested in a report by scientists for the European commission, which has become increasingly concerned that there is no policy to deal with the threat.
The European commission aims to put the options contained in the report - a series of papers from European and US scientists co-edited at Cambridge University - to the half-dozen European governments that have an interest in plutonium stockpiles, the vast bulk of which are at Sellafield. Britain's share is in excess of 100 tonnes.
The findings are being published in a special edition of the magazine Progress In Nuclear Energy. "Opinion is divided on whether the plutonium we have is a problem or an asset," said Bill Nuttall, one of the editors, from Cambridge's Judge Business School. "Our publication explores a range of options ranging from fuels for today's nuclear power plants and fuel for future reactor designs, right through to the possibilities for prompt disposal."
The Royal Society report in September proposed that the government burn as much plutonium as possible in the form of mixed plutonium and uranium fuel (MOX) in the Sizewell B pressurised water reactor in Suffolk, the only UK station able to use the fuel. Even this would only reduce the stockpile, not eliminate it, so the Royal Society suggested surplus MOX fuel - safer than pure plutonium - could simply be classified as waste and disposed of.
The problem with this policy is that Britain's MOX plant at Sellafield does not work properly and all of its limited output is contracted to foreign power companies. The government would have to build a new MOX plant to use British plutonium and persuade a sceptical privatised nuclear industry to burn it. In any event, MOX fuel is much more expensive to produce and potentially more dangerous than uranium fuel and so would require heavy government subsidy.
One of the other suggestions that is already technically feasible would involve mixing the plutonium in glass or ceramics. This would allow storing or burying blocks of material in a form where the plutonium would not cause a spontaneous meltdown, which has to be constantly guarded against at Sellafield.
Other suggestions involve mixing the plutonium with thorium to use as fuel in a new generation of reactors - so removing the danger while producing electricity - and using a particle accelerator to destroy the plutonium, but neither process is yet a proven technology and, although there are no costings in the report, could be expensive.
Nuttall said: "The Royal Society was clearly very concerned about the dangers of having so much untreated plutonium at Sellafield but came up with a narrow range of options. We have produced nine papers with a series of solutions so governments across Europe have a range of options without recommending any particular one."
Nuclear waste could power Britain
Proposed Sellafield fuel-processing plant could provide 60 per cent of UK's electricity until 2060
This article appeared in the Observer on Sunday December 23 2007 on p17 of the UK news section. It was last updated at 23:56 on December 22 2007.
A plan by the nuclear industry to build a £1bn fuel processing plant at Sellafield is being backed by the government's chief scientist. The plant would turn the UK's 60,000 tonnes of high-level nuclear waste into reactor fuel that will provide 60 per cent of this country's electricity until 2060, it is claimed.
'We can bury our reactor waste or we can treat it and then use it as free fuel for life,' said the cabinet's chief science adviser, Sir David King. 'It's a no-brainer.'
But the plan is controversial. A report by the Nuclear Decommissioning Authority, which operates the Cumbrian plant and backs the plan, acknowledges the move could have 'downside' economic costs, although it also stresses it has many benefits. In addition, green groups say the move would lead to the creation of 'a plutonium economy' in Britain that would see large quantities of nuclear fuel being transported across the country.
The Sellafield reprocessing plan would cost several billion pounds, a price that infuriates opponents of nuclear energy. 'There is no economic justification for this plan,' said Roger Higman, of Friends of the Earth. 'It would just be another massive subsidy for the nuclear industry. We should invest in renewables.'
But this criticism is firmly rejected by King. He has already helped persuade the government to back a new UK reactor construction programme scheduled to be approved in the new year. 'A UK citizen is responsible for emitting 11 tonnes of carbon a year on average,' he said. 'In France the figure is six tonnes - because France relies on nuclear power, which produces virtually no carbon dioxide. That is why we must replace our old nuclear reactors when they reach the end of their working lives.'
But building new reactors is controversial. Apart from their high construction costs, analysts say uranium could become scarce and expensive, with supplies from Canadian and Australian mines drying up in the next 20 years. Reactors would then have no fuel.
But this prospect is dismissed by King. 'We have a massive reserve of high-grade plutonium and uranium in Sellafield's nuclear waste,' he said. That stockpile - generated by Britain's reactors since the Fifties - contains six tonnes of plutonium and about 60 of uranium. However, it is mixed up with other highly radioactive reactor by-products.
To make nuclear fuel from this waste, its plutonium and uranium would have to be extracted, a task that can be achieved using Sellafield's Thorp reprocessing plant, though it will require a £1bn refurbishment to achieve this, said King. Alternatively, a new reprocessing plant will have to be built.
Then the plutonium and uranium will have to be turned into a fuel called mox, or mixed oxide. A plant to make mox could cost a further £1bn, or Sellafield's existing mox plant could be refurbished at a similar cost. Once these two plants - Thorp and mox - are ready, the 60,000 tonnes of nuclear waste, the leftovers of fuel production work and other highly radioactive material that has accumulated from Britain's nuclear energy programme, could be processed.
The resulting fuel rods and pellets could then be burned in nuclear reactors over the next few decades. In turn, the waste could be burned in a new generation of power plants called fast breeder reactors. Under this scheme, Britain would be near self-sufficient in nuclear fuel for the rest of the century. 'Studies carried out for the NDA have looked at a range of options for this material and shown that its use in a new generation of nuclear plants has potential viability,' said Bill Hamilton of the NDA. 'However any decision on such a programme is a matter for the government.'
This point was backed by King, who said the investment would be repaid by generating electricity.