With fossil fuel stocks in rapid decline and scientist around the world arguing the case for global warming, caused by increased CO2 emissions, the race is on to find both a greener and cheaper alternative to petrol. Bioethanol fuel may be one such possible contender, which is why both the mainstream car manufacturer Saab and the super car producer Koenigsegg now offer vehicles that can run on bioethanol.

Normal ethanol can be easily derived from petrol, however because bioethanol fuel is derived from plants it is viewed as a green fuel. The energy from the sun is used by the plants to make sugar, which in turn is converted into bioethanol. In addition during the growing process the plant is also absorbing high levels of carbon dioxide from the atmosphere, making the whole process greener than the refinement of conventional fossil fuels.

The bioethanol is produced firstly by the action of enzymes and microorganisms on the crops to release the starch and sugars, and then by a process of distilling and dehydration to produce a product that can be used as fuel in the internal combustion car engine. The added benefit of bioethanol is that it has a higher octane rating than standard fuel, 104 as against 97, and so using bioethanol will offer increased performance.

Sadly you cannot put bioethanol into a standard petrol combustion engine without first making some modifications. The engine management system needs to be upgraded, so that the engine can determine which fuel it is running on, and secondly the engine internal components need to be toughened up, because ethanol can react with certain materials to form corrosive acids.

Despite the changes required Saab now offers one of its most popular turbo charged models with a duel fuel option. It can run on either petrol or bioethanol and costs only a fraction more than the standard model, and from its car headlight bulbs through to its alloy wheels you would be hard pressed to spot the difference. Meanwhile Koenigsegg offer their CCX super car with a bioethanol option that can produce over 100bhp more than the petrol version.

Bioethanol does have its detractors, with environmentalists worried that as the demand for bioethanol grows, more land normally used for growing food stocks will be converted over to fuel production. One study has argued that to convert the whole of the US to bioethanol would take up three quarters of all of the world’s arable land.

Whilst Bioethanol certainly has green credentials it is not viable as a fuel for the masses in its current state, due to the huge land resources required. However there are now second generation biofuels derived from waste stocks and third generation biofuels derived from algae. Algae biofuels produce 30 times more energy per acre than biofuel crops, and so could ultimately be part of the future of green energy production.