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The V8 engines that have powered the big American sedans for the past 70 years are heading for junkyards, victims of the worldwide move to fuel efficiency.
Cleaner, greener production and concept vehicles using new-generation electric and hybrid powerplants and diesel engines overshadowed go-fast offerings at the Detroit motor show - although the American pick-up truck industry has stayed with the bigger V8 petrol powerplants for the immediate future.
Trademark V8 engines will give way to smaller high-tech V6 petrol and diesel engines, some mated to electric motors in hybrids.
The V8 won't die altogether - high-performance makers will still use it but widespread use is doomed since President George W Bush signed into law a 40 per cent reduction in the use of fossil fuel products in the United States by 2020.
V8s and Cadillacs have gone together like ham and eggs Stateside since the 1930s but the luxury arm of General Motors is looking at a 2.9-litre turbocharged V6 diesel for its mainstream US sedans. The 4.6-litre Northstar V8, which has powered Cadillacs since 1993, goes out of production in 2010. GM has said it won't replace it.
Cadillac general manager Jim Taylor said the company's future mainstream sedans would likely be powered by the more fuel-efficient 3.6-litre direct-injected V6 that went on sale in 2007.
The percentage of Cadillac buyers who want a V8 is declining. Only 10 to 15 per cent of Cadillac buyers insist on a V8, while the others choose the V6 powertrain.
"You have such a narrow gap now in terms of performance that smart consumers are saying, 'I don't need it'," said Taylor.
In 2009, the new 2.9-litre diesel goes into production for Cadillac's CTS to be sold in Europe and could also be used in US models. The same engine may also be available in Australasia after the car-maker launches in both countries later this year.
While Cadillac could accommodate a diesel in its US fleet, Taylor says it probably will remain a niche product.
"As long as BMW and Mercedes are going to have (diesel engines) and market them, those guys will lead the charge," said Taylor.
In the future, hybrid powertrains might replace V8 engines as a mark of prestige.
"The world changed with the signing of the new fuel economy bill," said Taylor. "That's the new world."
The new world sees GM investing in an Illinois company, Coskata, that aims to make ethanol from wood chips and other waste products. The cellulosic ethanol is described as the Holy Grail of biofuels. Coskata, formed in 2006, aims to produce ethanol using nonfood stocks for less than US$1 ($1.30) a gallon.
GM chief Rick Wagoner said using ethanol in all flex-fuel vehicles produced or planned by GM, Ford, and Chrysler would cut the US's petrol use by more than 80 billion litres - 22 billion gallons - or about 15.5 per cent of annual consumption. One step towards achieving this goal was to "invest heavily in the development of advanced cellulosic ethanol".
GM produces more than 1 million vehicles a year that are capable of running on petrol or E85, which is 85 per cent ethanol and 15 per cent petrol.
It initially will use the fuel at its proving ground in Milford, Michigan, and plans to approach governments in China, Europe and elsewhere to push for the use of cellulosic ethanol.
Cellulosic ethanol comes from material that otherwise might be thrown away - such as plant stalks, straw, sawdust and even household rubbish. Proponents say making and using such fuel will generate 88 per cent fewer greenhouse gas emissions than making and using petrol. For ethanol from corn, the figure is 18 per cent.
Ordinarily, to make ethanol, enzymes convert starches into sugars. Yeast or other micro-organisms cause the sugars to ferment then alcohol is distilled.
In the US, corn is the most common source of ethanol. Making ethanol from cellulosic materials is more difficult, largely because it's difficult to open the tough cell walls of plant waste.
Coskata bypasses the sugar step by converting the cellulose into synthesis gas, or syngas, before fermentation by proprietary micro-organisms, which produce ethanol. Syngas is a combination of carbon monoxide and hydrogen and is produced by gasifying materials that contain carbon.
The Coskata process is considered more efficient because it uses plant material that usually cannot be converted into ethanol through the sugar fermentation. Potentially, Coskata says, the process can be used to produce ethanol from various feedstocks, even old tyres.
The company will begin with wood chips as a feedstock.
- ADDITIONAL REPORTING BY AGENCIES
