with the rise in petrol prices we are once again focussing on alternate energy sources. i know that in my own state they are talking about going into partnership with brazil to produce ethanol.
biofuel-powered race car takes on le mans
a race car powered by pure ethanol is aiming to be the first to complete the le mans 24-hour endurance race in france, which starts on saturday 12 june.
new scientist is the official media partner for team nasamax, who hope their car will help raise the profile of alternative fuels such as ethanol. these fuels can dramatically reduce the pollution in exhaust fumes. and because the ethanol is produced from plants, its use does not pump additional carbon dioxide into the atmosphere.
the nasamax car has undergone an extensive engine redesign since 2003, when it made its first attempt at le mans and managed to complete 16 hours before the engine failed.
the key technical difference between the fuels is that the energy density of ethanol is a third less than petrol, which means more fuel must be carried onboard for a car to have the same endurance.
using ethanol also necessitates modifications throughout the engine and fuel delivery systems, including new fuel pipes and higher capacity pumps. these provide a higher fuel flow rate, so the engine produces the same power as a petrol engine.
in a test run at the track on wednesday night, its performance looked promising. "we clocked 340 km/h," says john mcneil, technical and renewables consultant for the team.
while motor racing is not an environmentally friendly sport - the high performance le mans cars manage just a few miles per gallon - some green groups see merit in the team nasamax's efforts.
powering a car on pure ethanol sends a useful message, says bryony worthington of friends of the earth uk. "renewable fuels are a useful step in combating pollution and global warming in combination with other measures."
pure ethanol vehicles have virtually no particulate emissions, and significantly cut the carbon monoxide and nitrogen oxide emissions that can cause smogs in cities.
just as importantly, the fuel makes no net contribution of the greenhouse gas carbon dioxide to the atmosphere. this is because it is produced from farmed biomass, such as sugar cane, corn, wheat, sugar beet or potatoes.
however, ethanol does have its drawbacks. converting all the world's cars to ethanol would be unrealistic, as the amount of farmland required to produce the biomass would be huge. for example, three tonnes of wheat produce just one tonne of ethanol. the production of such biomass can also require powerful and polluting fertilisers.
nonetheless, the fuel has already seen frequent use in countries such as brazil and sweden, and other countries are now following suit. in some places a mixture of ethanol and petrol is used.
car manufacturers such as ford, daimler chrysler and general electric, are now producing models capable of running on a mix of 85 per cent ethanol and 15 per cent petrol.
and there may be unexpected benefits too. according to mcneil, using ethanol makes the nasamax car smell better: "there's a whiff of crepe suzette as the car goes past."
10 june 04