It's not easy being green

Petrol - who needs it? Motoring editor ALASTAIR SLOANE and British writer JOANNA WALTERS look at the search for cleaner, greener alternatives.

The days of relying on fossil fuels for power and transport are surely numbered, now that their role in global warming is so well recognised.

But when will the "green" car finally have its day? Does it actually exist? Not totally.

Toyota has its Prius, a hybrid emission-reducing car using a conventional 1.5-litre petrol engine and battery power. It is being tested in New Zealand and sold in a handful of countries, including the United States. So too is the similarly powered 1-litre Honda Insight. Honda in Britain is selling a hybrid Civic. Ford New Zealand is pushing sales of its LPG-only Falcons, greener and cleaner than the petrol Falcons.

But none of these cars are totally green - that is, producing nothing but water vapour from their exhausts.

Five years ago alternative-fuel issues were hardly on the industrial radar screen. Now, all the world's major motor manufacturers have huge green programmes and boast senior executives with titles such as "vice-president, environment."

The prize for the company that first cracks the formula for the green car of the future will be measured in trillions of dollars. The prize for the human race will be cleaner air.

The bad news is that those same companies have found that solving the technology problem of alternative fuels is taking more time and money than they expected.

But while the most obvious alternatives to the car are still public transport, two-wheels or working from home, alternative-fuel vehicles are moving up the agenda.

Leading carmakers such as Ford, General Motors, Honda, Toyota, Volkswagen, DaimlerChrysler and BMW are busy researching what they see as the most likely future alternatives to petrol and diesel - and some are greener than others.

Most agree that the long-term solution will be cars powered by fuel cells that run on the electrical current generated when you combine hydrogen and oxygen through a catalytic membrane.

Ford is spending more than $1 billion to put a hydrogen-powered family car on the road in three years. BMW is taking its hydrogen fleet of 7-Series saloons on a world tour aimed at proving the feasibility, safety and desirability of the fuel.

But fuel cells are proving devilishly difficult to perfect at an affordable price and are still a long way off as a mass-market source of power.

Other avenues of exploration are battery power; bio-diesel, made from vegetable oil and methanol; liquid petroleum gas; liquefied natural gas; compressed natural gas; and hybrid engines.

Westport Innovations, based in Vancouver, Canada, is working for Ford on adapting diesel engines to run on natural gas, which is about one-twentieth as dirty.

It is focusing its research on Ford's British diesel engine plant at Dagenham, and with German truck maker Mann.

Westport chief executive David Demers says the rewards for the companies that produce the most successful alternatives to petrol and diesel vehicles are enormous.

The worldwide annual sale of new vehicles is worth about $2.3 trillion, and sale of fuel to power them around $4.6 trillion.

Demers says: "I think the majority of new car sales will still be powered by traditional methods in 20 years' time, although they will be much more efficient and probably totally recyclable.

"But even if that means almost half the market is taken up by alternative fuel vehicles, that is a huge potential."

But he adds that while all the innovations are very exciting, "I do not think we will be getting away from the internal combustion engine for at least another 50 years."