It is already too late to begin building more nuclear power stations. Even if new sites could be identified, the planning laws short-circuited and construction authorised within months, it will take almost a decade before new power plants could begin producing electricity. By that time Britain will be critically short of energy. Older nuclear plants will have been decommissioned, the gas-fired generators will be dependent on costly imported fuel and the exaggerated hopes for renewable energy generation will be left, like the few completed wind farms, blowing in the wind.

Political leaders have been warning the country about the impending energy shortages for years. For far too long they have tiptoed around a commitment to build nuclear power stations, however, because of the fallout, political and radioactive, from Chernobyl and vociferous opposition from the green lobby. A field in which Britain once led the world has been abandoned to competitors, especially the French, who now have a virtual monopoly in Europe in expertise.

Two things have changed recently, however. First, the worries about safety and the long-term dangers of nuclear contamination have been offset by the even more pressing need for energy generation that does not spew carbon into the atmosphere. And second, the accelerating run-down of Britain’s own oil and gas reserves and the growing dependence on energy from Russia and other less than reliable suppliers have reinforced the urgency of developing energy resources that are not subject to political blackmail or economic uncertainty.

Tony Blair, shortly before leaving office, committed his Government to an urgent new programme of nuclear power. Since then the momentum seems to have stalled. Yesterday, Ed Miliband, the Energy and Climate Change Secretary, insisted that Britain needed nuclear power, along with clean coal and renewables, and announced a list of ten potential sites for new nuclear reactors. Not before time, this is a recognition of the urgency of the problem, and of the scale of the solution required.

It should not, however, gloss over the huge obstacles that still mean, as the Conservatives insisted yesterday, that Britain is facing a national emergency over future power generation. Nuclear is never going to be a quick fix. First, no power station can be built quickly. The new Infrastructure Planning Commission should speed up previous unacceptably slow inquiries, and the choice mainly of existing sites for new reactors may avoid widespread local opposition. But nuclear reactors, given the potential for catastrophe, need intensive inspection and testing at every stage of their construction. This is especially true for the new generation of reactors developed by the French, one of which is now being build in Finland. Second, the cost of new reactors remains prohibitive — not because of running costs, but because the decommissioning of expired plants has proved hugely expensive. Future technology may one day make this cheaper, but commercial providers are now demanding expensive government guarantees.

Nonetheless, Mr Miliband’s announcement must be emphatically welcomed. Renewables will never be able to plug the energy gap and carbon capture for coal is also years away. With new nuclear power, the lights may yet stay on.