And Italy is not alone in its return to coal.

Driven by rising demand, high oil and natural gas prices, concerns over energy security and an aversion to nuclear energy, European countries are slated to build about 50 coal-fired plants over the next five years.

Coal plants that will be in use for the next five decades have sprung up in Germany, the Czech Republic and Britain.

Europe's power station owners emphasise they are making the new coal plants as clean as possible. 'This will be the cleanest coal plant in Europe. We are hoping to prove that it is possible to make sustainable and environmentally friendly use of coal,' said Mr Gianfilippo Mancini, Enel's chief of generation and energy management.

But critics say that 'clean coal' is a pipe dream. 'Building new coal-fired power plants is ill conceived,' said Mr James Hansen, a leading climatologist at the Nasa Goddard Institute for Space Studies.

'This plan is like barging into a war without having a plan for how it should be conducted, even though information is available.'

Fewer new coal plants are expected in the US, in part because of the difficulty in securing regulatory permits and in part because nuclear power is an alternative.

But in the developing economies of India and China, coal remains a major fuel source.

Now, eco-conscious Europe's decision to turn to coal is causing alarm among environmentalists who warn that it is setting the world on a disastrous trajectory that will make controlling global warming impossible.

With nuclear energy not an option in Italy and Germany, many electricity companies including Enel say they have little choice but to build coal plants.

Fuel costs have risen 151 per cent since 1996, and Italians pay the highest electricity costs in Europe.

Proponents argue that coal is cheap, reserves will last for 200 years, and more importantly there is no coal cartel - so there is more room to negotiate prices.

By using new technology, clean coal plants can reduce the amount of sooty particles spewed into the air. However, the essential technology of carbon capture and storage is not commercially available.

Enel says it will start experimenting with carbon capture technology in 2015, in the 'hopes for a solution' by 2020.

'That maths was short-sighted,' said Dr Stephan Singer, who runs the European energy and climate office of WWF.

'If they want coal to be part of the energy solution, they have to show us that carbon capture can be done now, that they can really reduce emissions' to an acceptable level, he said.

Meanwhile, in the towns surrounding Civitavecchia, the impending arrival of a huge coal plant, with its three silvery domes, is being greeted with a hefty dose of dread.

'They call it clean coal because they use some filters, but it is really nonsense,' said Mr Marza Marzioli, spokesman for the No Coal citizens group in the nearby town of Tarquinia. 'If you compare it to old plants, yes it's better, but it's not 'clean' in any way.'

NEW YORK TIMES