Nuclear decommissioning: the problem that won't go away
As governments across the world build more nuclear power stations, disposing of the old and dirty reactors is becoming big business, writes Conal Walsh
IT IS A sprawling landscape of chimneys, storage ponds filled with nuclear waste and radioactive buildings awaiting demolition. The UK's Thorpe nuclear-processing plant at Sellafield – nestled somewhat incongruously among the picturesque hills of Cumbria, northern England – is unlikely ever to become a tourist attraction, despite its fame.
For decades, Sellafield has been officially the most hazardous building in western Europe (according to the Nuclear Decommissioning Authority). And disposing safely of its crumbling, highly radioactive edifices, its hastily dumped reactor parts and decaying fuel rods is a slow and painstaking job that will probably ensure Sellafield holds the same dubious accolade for decades more.
Dismantling half a century of nuclear detritus is ugly and dangerous work – but it may also be very lucrative. Mindful of their Kyoto Protocol commitments to reduce carbon emissions and concerned about their future energy needs, many developed nations are embracing civil nuclear power.
There are 441 nuclear reactors operating in 30 countries, with a total capacity of about 386 gigawatts (see Table 1 and Figure 1). But the OECD expects global nuclear capacity to increase by a factor of between 1.5 and 3.8 by 2050; French power company Areva estimates that between 100 and 300 new reactors could be built by 2030.
Upsurge in capacity
This upsurge in capacity will feed robust energy demand in growing economic superpowers, such as China and India, and replace fossil fuels as the main source of power in many mature economies. In countries such as China, the new power stations will be among the first of their kind. But in the developed world, an important part of the uptake in nuclear usage will involve decommissioning, as older facilities are replaced by a generation of cleaner, more productive reactors.
The UK, for example, has set aside £73bn ($120bn) for its own radioactive clean-up operation, as several 30- and 40-year old plants come to the end of their predetermined life-spans. And power companies are eager to take advantage of this spending.
Electricité de France (EdF), controlled by the government of France, where civil nuclear power has been the norm for decades, seized the opportunity to deploy its experience and build capacity in the UK when it bought British Energy (BE) for £12.1bn last year. The deal gives EdF the right to decommission and replace seven nuclear sites that supply around 15% of the UK's electricity, but are set for retirement over the next 15 years. The UK's Nuclear Decommissioning Authority has also sold sites to Germany's RWE and E.On to build new reactors and oversee other old plants.
Sellafield itself – and, in particular, the prize of land close to the existing site, which has been identified as suitable for new nuclear facilities – is up for auction.
But managing these assets carries financial risks as well as rewards. As large as £73bn might seem, there have been repeated warnings that the true monetary cost of a nuclear clean-up is unquantifiable at present. Scientists and government officials have only a vague idea about the nature and quantities of waste deposited decades ago, and still festering in the cooling tanks, at Sellafield. Within the industry, there are rumours of EdF scientists reacting with horror once they began to assess the scale of the task confronting them at BE's nuclear sites.
To some extent, this problem is not so acute outside the UK. The country's relatively large stockpile of radioactive waste is partly a function of time: it has been involved in nuclear research since the 1940s. Its nuclear plants are more difficult and expensive to dismantle because, unlike France's, they were not developed as part of a co-ordinated national energy strategy, but appeared haphazardly and were often designed on a bespoke basis, which means they now require bespoke solutions.
In the event of decommissioning cost overruns, companies such as EdF will not have to shoulder much of the additional financial burden. Ultimately, the UK government underwrites the cost of decommissioning. If that cost rises too far, however, nuclear power becomes difficult to justify to taxpayers – and that, in turn, might imperil the ambitions of EdF and others to become the country's principal energy suppliers in the future.
Nuclear energy has many persuasive opponents. "[Nuclear reactors] are not safe," Charles Barnett, chairman of the UK's Shutdown Sizewell Campaign, said recently. "With the heightened risk of terrorism, it's foolhardy to build more. They are very expensive and they leave a legacy of dangerous waste."
The argument about waste is hotly disputed. In contrast to their older predecessors, new reactors produce little waste and pose few threats to the environment, say industry figures, who point to the example of France, where 75% of electricity is generated by nuclear fission and waste is safely reprocessed. To the 270,000 tonnes of spent fuel in storage worldwide, only 3,000 is added each year, with the bulk of new waste successfully recycled.
Nonetheless, there remains a great deal of uncertainty about atomic energy among policymakers and the general public. The long-term investment demanded by an ambitious nuclear programme could, for example, divert money and attention away from the development of safer, cleaner alternative sources of energy, such as wind, sea and solar.
Neither side has won the argument everywhere. While France has remained steadfast in its support of civil nuclear energy, for example, Italy only recently reversed its long-standing opposition and Germany, Europe's biggest economy, is still officially committed to phasing out all of its 17 remaining reactors by 2021. The issue has not yet climbed far up the public agenda in the US, which has numerous nuclear power stations, but also relatively plentiful access to coal (see p16).
Arguably the biggest and most contentious remaining question about decommissioning is: where will mankind store its nuclear waste? Disposal methods in use at present do not dispose of high-level waste at all; rather, waste that cannot be recycled is vitrified in glass, encapsulated into heavy steel cylinders and then buried underground.
Some scientists say deep underground disposal protects waste from human interference, earthquakes and climate change, and several countries are investigating the permanent burial of radioactive material at depths of hundreds of metres in clay, rock salt and granite geological formations.
France, the UK and Canada have declared that underground storage is the answer, although some non-governmental organisations, including Greenpeace, say it cannot be guaranteed that radioactivity will not escape in the long term. Potentially suitable geological sites for storage have been identified in Sweden, Finland, Germany, Japan and elsewhere, but final approval in those countries has not yet been secured. The US has the only active deep repository for the disposal of defence-related radioactive waste, in New Mexico, but waste storage remains controversial there as in other countries.
President Barack Obama opposes the opening of the Yucca mountain nuclear waste storage site in Nevada. Meanwhile even the most supportive governments are prioritising reversibility within their waste-management strategies, as they want to retain the ability to extract stored waste if they change their mind in future.
The political and scientific arguments are likely to continue. But because it takes hundreds of thousands of years for spent nuclear fuel to become non-radioactive, the question of what to do with it is not going away.