An End to Nuclear Waste?
Plutonium is the nuclear nightmare. A by-product of conventional power-station reactors, it is the key ingredient in nuclear weapons. And even when not made into bombs, it is a million-year radioactive waste legacy that is already costing the world billions of dollars a year to contain.
And yet, some scientists say, we have the technology to burn plutonium in a new generation of “fast” reactors. That could dispose of the waste problem, reducing the threat of radiation and nuclear proliferation, and at the same time generate vast amounts of low-carbon energy. It sounds too good to be true. So are the techno-optimists right — or should the conventional environmental revulsion at all things nuclear still hold?
Fast-breeder technology is almost as old as nuclear power. But after almost two decades in the wilderness, it could be poised to take off. The U.S. corporation GE Hitachi Nuclear Energy (GEH) is promoting a reactor design called the PRISM (for Power Reactor Innovative Small Modular) that its chief consulting engineer and fast-breeder guru, Eric Loewen, says is a safe and secure way to power the world using yesterday’s nuclear waste.
The company wants to try out the idea for the first time on the northwest coast of England, at the notorious nuclear dumping ground at Sellafield, which holds the world’s largest stock of civilian plutonium. At close to 120 tons, it stores more plutonium from reactors than the U.S. and Russia combined.
While most of the world’s civilian plutonium waste is still trapped inside highly radioactive spent fuel, much of that British plutonium is in the form of plutonium dioxide powder. It has been extracted from spent fuel with the intention of using it to power an earlier generation of fast reactors that were never built. This makes it much more vulnerable to theft and use in nuclear weapons than plutonium still held inside spent fuel, as most of the U.S. stockpile is.
The Royal Society, Britain’s equivalent of the National Academy of Sciences, reported last year that the plutonium powder, which is stored in drums, “poses a serious security risk” and “undermines the UK’s credibility in non-proliferation debates.”
Spent fuel, while less of an immediate proliferation risk, remains a major radiological hazard for thousands of years. The plutonium — the most ubiquitous and troublesome radioactive material inside spent fuel from nuclear reactors — has a half-life of 24,100 years. A typical 1,000-megawatt reactor produces 27 tons of spent fuel a year.
None of it yet has a home. If not used as a fuel, it will need to be kept isolated for thousands of years to protect humans and wildlife. Burial deep underground seems the obvious solution, but nobody has yet built a geological repository. Public opposition is high — as successive U.S. governments have discovered whenever the burial ground at Yucca Mountain in Nevada is discussed — and the cost of construction will be huge. So the idea of building fast reactors to eat up this waste is attractive — especially in Britain, but also elsewhere.
Theoretically at least, fast reactors can keep recycling their own fuel until all the plutonium is gone, generating electricity all the while. Britain’s huge plutonium stockpile makes it a vast energy resource. David MacKay, chief scientist at the Department of Energy and Climate Change, recently said British plutonium contains enough energy to run the country’s electricity grid for 500 years.
Proponents of fast reactors see them as the nuclear application of one of the totems of environmentalism: recycling. But many technologists, and most environmentalists, are more skeptical.
…John Sauven, director of Greenpeace UK, and Paul Dorfman, British nuclear policy analyst at the University of Warwick, England, argued recently that this made all nuclear options a poor alternative to renewables in delivering low-carbon energy. “Even if these latest plans could be made to work, PRISM reactors do nothing to solve the main problems with nuclear: the industry’s repeated failure to build reactors on time and to budget,” they wrote in a letter to the Guardiannewspaper. “We are being asked to wait while an industry that has a track record for very costly failures researches yet another much-hyped but still theoretical new technology.”
But this approach has two problems. First, climate change. Besides hydroelectricity, which has its own serious environmental problems, nuclear power is the only source of truly large-scale concentrated low-carbon energy currently available. However good renewables turn out to be, can we really afford to give up on nukes?
Second, we are where we are with nuclear power. The plutonium stockpiles have to be dealt with. The only viable alternative to re-use is burial, which carries its own risks, and continued storage, with vast expense and unknowable security hazards to present and countless future generations.
For me, whatever my qualms about the nuclear industry, the case for nuclear power as a component of a drive toward a low-carbon, climate-friendly economy is compelling. [A few months ago, I signed a letter with Monbiot and others to British Prime Minister David Cameron, arguing that environmentalists were dressing up their doctrinaire technophobic opposition to all things nuclear behind scaremongering and often threadbare arguments about cost. I stand by that view.]
Those who continue to oppose nuclear power have to explain how they would deal with those dangerous stockpiles of plutonium, whether in spent fuel or drums of plutonium dioxide. They have half-lives measured in tens of thousands of years. Ignoring them is not an option.