Geoffrey Lean: If nuclear power is the answer, they're asking the wrong question

Suddenly, after two decades out in the cold, nuclear energy is hot again. Tony Blair has told aides that he will crusade for atomic power as the answer to global warming - and yesterday his new Secretary of State for Trade and Industry duly promised a review of the Government's hitherto sceptical position later this year.

Suddenly, after two decades out in the cold, nuclear energy is hot again. Tony Blair has told aides that he will crusade for atomic power as the answer to global warming - and yesterday his new Secretary of State for Trade and Industry duly promised a review of the Government's hitherto sceptical position later this year.

An astute PR campaign - coupled with the incompetence and complacency of the wind- power industry - has persuaded fashionable opinion that it is greener to generate electricity from the atom than from the wind. This week the Government's own Sustainable Development Commission will launch a fightback. But the debate, though intense, is no more than a side-show to the real action that is needed to minimise climate change.

The case for nuclear power is beguilingly simple. Global warming, by almost universal scientific consent, is the greatest crisis facing the planet. Unlike fossil fuels, nuclear power emits none of the carbon dioxide that mainly causes the problem.

Moreover, almost all Britain's ageing reactors will come to the end of their lives over the next 15 years or so. Unless they are replaced by up to 12 new nuclear plants, it will be harder to reduce the emissions in time.

That is all true, but less compelling than it seems - because replacing the old reactors will make only a relatively small contribution to the fight against global warming. Nuclear power generates only about a quarter of Britain's electricity and, in turn, electricity generation contributes only about a quarter of Britain's carbon dioxide. So the debate is over about 6per cent of emissions - just a 10th of the 60 per cent of reductions the Government needs to make by 2050.

Pressed on the point, nuclear advocates say that this is an argument for even more nuclear power. A top DTI official argued last summer that atomic power would have to be expanded to provide half Britain's electricity. But this would still account for only about a fifth of the needed reductions.

Even the smaller programme could be not achieved in time, if at all. The latest scientific evidence shows that we have about a decade in which to begin seriously to cut emissions worldwide. Even if the decision were taken today, it would take about that long just to get the first new reactor on stream.

Replacing Britain's ageing nuclear plants would mean completing a new one on average about once a year between 2010 and 2020 - a virtually impossible task. The last time a government tried to build 10new nuclear power stations, in the early 1980s, it managed only one - years behind schedule.

Better than nothing? Sure. But the vast sums needed - at least £4bn, probably nearer £9bn - could almost certainly be more effectively spent elsewhere.

The Prime Minister's own Performance and Innovation Unit (PIU) concluded that nuclear power was twice as expensive as wind energy.

Then there are questions of safety. A single catastrophic nuclear accident - or a terrorist attack - anywhere in the world would bring the programme to a halt. Generic faults tend to occur in reactors, causing them all to be shut down for repairs. And the Government's own adviser on nuclear waste yesterday insisted that no new ones should be built until we had solved the problem of disposing of it.

In a straight fight, wind wins on all these points. It is cheaper, much quicker to build, infinitely safer - and Britain has the best natural wind resources in Europe. But, given its performance so far, it is doubtful whether it can expand fast enough. And it, too, addresses only electricity generation.

If there were no alternative, it might be wise to plump for both. Sir David King, the Government's Chief Scientific Adviser, suggests that a single generation of nuclear plants could be built while renewables get ready to take the strain. But nuclear drives have always stifled renewable developments - and the atomic obsession in the DTI threatens to do so again.

Since the reactors are unlikely to be built in time, we would be left with little or nothing.

There is, however, a way through - almost entirely ignored in the debate. Saving wasted energy is less glamorous, but much more effective. It addresses all energy use, not just the fraction that goes to produce electricity, and can take effect instantly. The PIU concluded that Britain could cost-effectively save a third of its use - cutting emissions dramatically - without any slackening of growth in the economy or in living standards. Just changing every light bulb in the US, for example, would close 40 nuclear power plants. Every pound spent on such energy efficiency saves seven times as much carbon dioxide as when it is spent on nuclear power.

But Blair has rejected this common-sense approach, saying he opposes making people change their lifestyle doing such things as "buying energy-efficient refrigerators". Like Tony Benn 40 years ago, he is bewitched by the white heat of technology. That led to the Government's humiliating defeat over GM foods and crops. It is likely to produce a similar nuclear débâcle.