"THE worst possible nuclear disasters are not as bad as the worst possible climate change disasters," declared the Centre for Alternative Technology in Britain recently, urging "a modest revival of nuclear energy . . . to sell the idea to the sceptics."

And while Europeans and North Americans are still reluctant to build new nuclear power stations, recalling the disasters at Chernobyl and Three-Mile Island around two decades ago, Asians have no scepticism: China plans to build two large new nuclear reactors a year for the next 16 years.

In the rest of the world, the number of new nuclear reactors under construction barely balances the number being retired at the end of their lives, but it's boom time in Asia: 16 of the 27 nuclear power stations now being built worldwide are in China, India, Japan and South Korea.

That is largely because Asia has had no similar reactor disaster that alienated public opinion from nuc-lear power, but there are signs that European and American governments are also starting to reconsider new nuclear power plants.

Only a year ago, the whole nuclear power industry was facing a death sentence in the West. No new nuc-lear reactor had been ordered in the United States for 25 years, and only one was under construction in all of Europe (in Finland).

Indeed, a number of European countries that currently get much of their electricity from nuclear power generation, including Germany (28%), Belgium (55%) and Sweden (58%), had decided to phase out their existing plants.

The last-minute reprieve was almost entirely due to the growing anxiety about global warming.

In the past year, popular belief in the reality of climate change has passed the tipping point, leaving doubters an increasingly isolated minority.

At the same time, Russia's decision to ratify the Kyoto Accord on reducing greenhouse gas emissions is making the idea of paying for excess carbon emissions a reality, which transforms the economics of low-carbon energy sources like nuclear power. Oil at $US54 a barrel doesn't hurt the competitiveness of nuclear energy either.

The original wave of enthusiasm for nuclear power in the 50s and 60s, an uncritical love affair with high-tech, created most of the 444 nuclear plants now operating on the planet.

In France, reliance on nuclear power for electricity attained the remarkable level of 78%, but typical levels for large industrialised countries are more like Japan's 25, Britain's 24 and America's 20%.

Worldwide, nuclear power accounts for about the same share of all electricity generation as hydro-electric power, but far less than the share of oil, gas and coal.

In a world of cheap, plentiful fossil fuels and no worries about carbon dioxide emissions, the low capital cost and short build time of oil-, gas- and coal-fired generating plants put the nuclear power industry at a huge disadvantage, and concerns about nuclear safety provided the coup de grace.

But when oil gets expensive and future reserves get scarce, the shoe starts shifting to the other foot -- and then rising concern about carbon emissions does the rest.

As the International Atomic Energy Agency noted recently, nuclear power's 16% share in global electricity generation saves around 600 million tonnes of carbon emissions per year.

By contrast, electricity generated by burning fossil fuels accounts for a third of the entire human contribution to greenhouse gases worldwide. The whole nuclear power cycle, from uranium mining and reactor construction to waste disposal, has a carbon emission cost comparable to solar power and wind power -- so, suddenly, nuclear is sexy again.

The nuclear power lobby has leapt on this new argument for its product.

"With carbon emissions threatening the very stability of the biosphere," says Ian Hore-Lacy of the World Nuclear Association, "the security of our world requires a massive transformation to clean energy."

Well, he would say that, wouldn't he?

But is this really going to push the world back into a major commitment to nuclear energy?

In many ways, the case for nuclear power today is a different argument from that of 20 years ago.

Modern reactor designs are less complex and, therefore, safer than their predecessors, using fewer pumps and other moving parts, and far less of the pipes and cables where problems most often occur.

They produce around a tenth as much nuclear waste as older designs, and there are better methods of disposing of the waste. On the other hand, reactors take an eternity to build -- eight to 10 years is a quite normal construction time -- and their capital cost is immense.

The jubilation in the nuclear power industry is probably premature.

There will certainly be more reactors built than seemed likely a year or two ago. Indeed, it would be surprising if their numbers didn't double or triple in the next quarter-century.

But the very slowness of their construction makes them poor candidates for a quick-fix in an accelerating climate change crisis.

Solar energy, wind and other natural forces can be exploited to meet rising demands for electrical power far more quickly: Britain hopes to be generating 15% of its electricity from wind-power in the next five years.

Simple conservation measures are even faster and cheaper. The Rocky Mountain Institute calculates that saving a given amount of electricity by using energy more efficiently costs only a seventh as much as generating the same amount of energy through nuclear power.

So expect to see a few more nuc-lear power stations, even in Europe and North America, but not block-forests of the things.

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