The argument over which is the more eco-friendly option for powering vehicles - electricity or new liquid fuels - is no closer to being resolved following recent
biofuel testing.
Swiss materials science and technology institution Empa looked into how different types of fuel - including hybrid electric engines and natural gas - perform in terms of CO2 emissions under different driving conditions.
It found that, in urban conditions, pure electric vehicles offer the smallest carbon footprint, as they can cover short distances using only battery power.
Over longer distances, however, liquid fuels become the better performers as the electric component of a hybrid engine has a negligible contribution in bringing a car to motorway speeds.
Further
biofuel testing in the years to come may help to resolve this reliance on gasoline through innovations such as the renewable butanol developed at Edinburgh Napier University from whisky waste products.
This offers 30 per cent more power than ethanol and can be used in existing engines without conversion, the scientists say.