US researchers have conducted an interesting cost-benefit analysis which shows diesel engines are your best choice, if saving money is what you're interested in.
The research team calculated the individual and societal costs and benefits of conventional petrol vehicles, petrol-electric hybrids, high-tech diesels and flex-fuel vehicles burning E85 full time.
The result? Unless petrol prices rise to around $1.50 or more in the next few years, or ethanol prices drop considerably, diesel's the best overall solution; E85's the worst.
The findings even surprised the researchers who were expecting hybrids to top the list. The study finds that modern diesel engines provide better performance and fuel economy for the price than hybrid cars (environmental issues were not considered).
The research found that over a vehicle's life, an E85 powered vehicle (which runs on 85 per cent ethanol and 15 per cent petrol) would cost an extra $US1600 over a conventional petrol car, while a diesel could save as much as $US2300.
Apart from the enormous energy required to create E85 fuels (which as has been shown, generally cancels out the environmental benefits of E85), ethanol itself has less than 70 per cent of the energy of petrol - the more ethanol in the blend the less energy and the less kilometres per litre.
For more information and a link to the research paper click here.