How green is your car? - Ford's vision

Ford says it is working at ways to improve its manufacturing processes and is planning to build many more lightweight, hybrid electric and bio-fuel cars. One target is to build a cleaner Focus that is capable of more than 70mpg.

Lewis Booth, Ford of Europe boss, is also urging environmental sustainability through a reduced emphasis on the use of fossil fuels such as petrol and diesel. He plans more cars that run on alternative fuels such as E85 ethanol, which is made from crops including wheat and sugar that remove carbon dioxide from the atmosphere when they are growing.

Speaking at July's British International Motor Show, Booth also questioned the UK Government's system of taxing cars solely on tailpipe emissions. He recommended an alternative system based on the impact of the fuel source – a so-called 'well to wheel' approach.

At present, the UK Government taxes cars based on tailpipe emissions and does not factor in their lifetime environmental costs. Road tax is split into seven bands and cars in the highest C02 band will cost their owners £215 per year, while cars in the lowest band are exempt. Currently, Honda Civic Hybrid and Toyota Prius owners pay £50 a year because both cars are in the second-lowest band.

The Treasury told What Car? there are no plans to change the system of taxation to fall in line with the 'dust to dust' environmental cost of cars, but will not rule out that method, either. 'Hybrid technology is fairly new, but it is likely that the energy costs will fall as the manufacturing process becomes more efficient,' said a Treasury spokesman. 'Currently the taxing system is a signal to consumers to show how environmentally friendly their cars are.'

The Society of Motor Manufacturers and Traders accepted that taxing cars on the basis of tailpipe emissions is 'not a perfect solution', but it does give a reasonable indication of how well the industry is progressing with environmentally friendly technology. 'It is impossible to truly measure how 'green' a car is because there are so many interdependent factors that affect it during its lifespan,' said an SMMT spokesman. 'It is difficult for lawmakers to include other aspects of a car's technology because they have to make legislation simple for consumers to understand.'