T Troughton talks to one of the UK's saner environmental thinkers.

The ice-caps are melting. Sunlight, which used to be reflected back by the snow and ice, is being absorbed by the newly exposed soil. The temperature of the planet is continuing to increase, producing more carbon dioxide and methane, and resulting in a vicious spiral of global warming. It could, some scientists are suggesting, already be too late to stop it.

The resulting panic - affecting everyone from the Queen to activists - has, at least, encouraged debate about alternative energy. In the UK, lobby groups are currently campaigning on everything from windpower to waves. But every option has vociferous opponents. Greenpeace, for example, have established that the whole of the UK's energy needs could be provided by off-shore windfarms. But these, say critics, are crazily expensive to build and transport. While for every community welcoming an on-shore windfarm (Buckinghamshire residents recently celebrated the installation of five turbines to supply 3,700 homes); there's another fighting what they see as monstrous machines with equal conviction.

One of the options being touted is, of course, nuclear energy (see page three for more details). All but one of the UK's reactors will have to close by 2020, and the Blair government are hinting that more may be needed. Opponents point to the nuclear industry's appalling safety record, with its history of leaks and cover-ups, as well as the devastating consequences of an explosion.

"And" says Dr Geoffrey Haggis, decisively, "we still don't know what to do with the waste. No-one does. Wherever you try to put it, local people object. Also, if we're going to go nuclear, other states will follow. We'll see proliferation in politically unstable countries, where waste disposal is even more of a problem. Fortunately, there's no need to go down that route".

Dr Haggis is a former Edinburgh University physicist, whose book; Tomorrow's Energy (finding solutions to the problems of global warming and future energy supply) took four years to write. With coal demonised as a supplier of greenhouse gases, it is not fashionable to point out that we have enough for the next hundred years, but Haggis does, and moreover has a solution to dispose of the gases. "We can adapt power stations to trap the carbon dioxide and then pump it out under the North Sea" he explains. "Some environmentalists are against the idea, because they think the people proposing it are in the pay of the oil and gas industry. But I know the people who are working on it, and it's a perfectly good and possible solution".

In the meantime we can develop renewables. Haggis concludes that an imaginative mix of building redesign, photovoltaic panels (which, if fitted to every house in the UK would supply 50% of energy needs) and off-shore windfarms would do the trick. He sees a future in which people will move to working locally and buying local food - and sucks to the corporations and the supermarkets. And he has even come up with a response to the idea that we may already have passed the point of no return.

"In which case" he says cheerfully, "People will panic. And after they've panicked, we can reverse global warming by erecting giant canvas curtains saturated with a solution of calcium hydroxide. The calcium hydroxide will absord the carbon dioxide in the atmosphere and react with it to produce calcium carbonate. The curtains would probably have to be frilly, so the calcium carbonate can drip down them".

Dr Haggis can be reached at eutot@sdev.fsnet.co.uk