“What company could credibly make an investment commitment now that would only be completed in 2021?” asks Professor Steve Thomas of Greenwich University, UK, referring to the eight-year planning and six-year construction period necessary if nuclear plants were given a firm go-ahead in the UK in 2007.

But nuclear may have the upper hand where operational costs are concerned. It is usually considered very economical to run in the longer term. “Once a nuclear power station is built, it is a cheap source of electricity; the fuel cost is very low compared to other sources, for business users,” says Andreas Biermann, an analyst at the IEA.

Environmental activists, however, argue that nuclear generation and other operational costs are underestimated. “The cost of waste management has to be taken into account in the budget for hundreds of years, but usually it is built into the accounts for only 40,” argues Frank van Schaik, a campaigner at Friends of the Earth Europe.

Thomas points out the enormous variations in cost estimates due to the lack of experience in recent nuclear build, which creates economic models that are more subjective than for other industries with a more recent track record. “The favourable forecasts of nuclear costs published in the last five years have all been based on highly optimistic assumptions,” he says.

Looked at from most angles, nuclear power is a headache and is risky as a commercial proposition. On the surface, Denmark’s decision to abolish it seems wise – and Denmark looks set to be followed by Germany, Spain and Italy. France remains the most nuclear-dependent country in Europe, relying on 77% of its electricity from this source. Why does France continue to depend on nuclear power while others are opting to be free of the planning, pollution and political hassle it involves?

One answer is the historic relationship between the state and EDF, France’s main energy supplier, which is still largely in public hands. “In France, the taxpayer is prepared to pay for nuclear energy, and it has a long history,” explains van Schaik. “For French people, it’s ‘the way it is’ and they’re used to it.” Nuclear power was part of Charles de Gaulle’s vision of an independent France in a peaceful Europe, because its supply was reliable and secure and could be found locally.

The other advantage for France is that nuclear has allowed it to more easily meet its Kyoto Protocol responsibilities, owing to the climate-friendly aspect of nuclear energy – the fact that it doesn’t produce CO₂. Indeed, there is a growing lobby of non-traditional “greens” like the scientist James Lovelock who are ardent supporters of nuclear energy as the only viable long-term solution to global warming.

Nuclear may also address the politics of energy security, part of de Gaulle’s original vision. “We consider nuclear to be a domestic fuel source,” remarks Biermann. “By removing it you are essentially reducing fuel diversity and are more vulnerable to supply shocks.” This is one reason why the IEA has forecast that nuclear will still make up between 6% and 11% of the EU’s primary fuel mix in 2030, as fossil fuel imports are growing.

In a response to the European heads of state decision in March to adopt a 20% target for the development of renewables by 2020, industry lobby group Business Europe urged that the implementation of the target “must leave all other energy options open, in particular the use of nuclear energy” because of energy supply considerations in the face of global warming.

Some renewable energy forms, like wind power, do not demonstrate adequate despatchability (the capacity to generate power at the time it is needed) and are thus sometimes considered unreliable. They may need to be backed up by fossil fuel plants at times. This is true even in Denmark, which has in fact simply pushed nuclear beyond its national boundaries and relies on its neighbours for many dirtier fuels. Denmark is in the convenient position of having a very interconnected grid, so that it can import electricity very easily from Sweden (nuclear), Norway (hydro) and Germany (coal).

In the same way, Germany’s decision to phase out nuclear power may involve importing electricity from fossil fuel or nuclear sources in eastern Europe and France.

“It is expensive but no less risky to replace nuclear power in Germany,” asserts Biermann. “The chief impact is that CO₂ emissions will go up as a consequence of shutting down nuclear. They want to use clean energy and energy efficiency to replace it, but why not use all three to prevent climate change?”