Accidents at nuclear power facilities are rare. And even in an incident as serious as the one that occurred last year at the Fukushima Daiichi Nuclear Power Station, the damage was ultimately contained within certain limits. But the risks associated with nuclear power are often portrayed as simply unacceptable, and publics in many countries continue to view nuclear power as fundamentally dangerous. To understand more about this phenomenon, it is useful to compare the risks posed by nuclear energy with the dangers presented by other methods of base-load electricity generation -- fossil fuel combustion and hydropower.
In one sense, a power plant running on fossil fuels poses only a low risk to public safety. True, an explosion at such a facility could threaten the lives of people who live in the immediate area, but the danger does not extend beyond that. The real danger posed by fossil fuels is pollution. To begin with, burning these fuels produces pollutants like sulfur dioxide and nitrogen oxides, which have direct and negative consequences for human health. Even more significantly, burning these fuels produces carbon dioxide, the primary cause of the global warming that threatens to alter life on this planet radically. Though power plants' carbon emissions will likely be reduced in the future through technologies like carbon capture and sequestration, significant carbon emissions seem a certainty for an indefinite period of time.
Hydropower, meanwhile, is widely regarded as a safe source of energy, with easily manageable risks. An argument can certainly be made that dam construction creates environmental problems, but the operation of hydropower plants does nothing to aggravate global warming. Quite the opposite -- if global warming causes water flow through river basins to become more irregular, it is climate change that may harm hydropower facilities. On a similar note, some hydropower plants may suffer if fossil fuel exploitation reduces the availability of water to hydroelectric facilities -- in China, for instance, coal mining places great stresses on water resources.
Given all this, it is not difficult to argue that fossil fuel combustion represents a greater set of dangers than does nuclear power -- or, for that matter, than hydropower, which is in a sense nuclear power's "natural ally." Still, according to public opinion surveys examined in a 2010 report published by the Organisation for Economic Cooperation and Development, majorities in only two of 18 countries supported building nuclear power plants in order to combat climate change.
If nuclear energy is to become a more significant tool in the fight against global warming, proponents of nuclear energy must accept that nuclear power comes with a certain degree of risk -- and sometimes in the form of accidents. Then again, proponents must contend with two other dangers related to nuclear energy that are generally not exaggerated. The first is nuclear weapons proliferation; other sources of energy, it must be admitted, present no risk equivalent to proliferation. The second is at the back end of the fuel cycle, mainly involving the disposal of spent fuel. This risk, in some ways, may be underappreciated by the public.
Anti-proliferation efforts are an ongoing political project; the dangers of the fuel cycle may likewise be addressed through multilateral initiatives and technological advances. But public fear about safety at nuclear power plants remains a serious obstacle to nuclear expansion, and therefore to progress against climate change.