Cars running on bio fuel

[Primrose]

I'm having a personal debate with myself as to whether I'll be doing less damage to the environment by keeping my 8 year old car which runs on petrol rather than swapping it (if I could afford to !) for a newer model which uses bio fuel.
The more I read about the damage bio fuels are doing in terms of causing deforestation of the rain forests and taking up land which should be used for the production of food (wheat, grain, etc), the more I wonder whether a mass move to bio fuel is shooting ourselves in the foot. What do others think? I fear that if the bio fuel bandwaggon really starts rolling internationally, it will be a hard thing to stop it in its tracks.

[Stephen]

Primrose
A really difficult and complex debate.
CO2 emmisions or displacement of food crops?
Cost of running or capital cost?
Same again but environmental rather than financial (lots of the environmental costs of motoring are in the building and the end-of-life stages particularly with the modern use of plastics)

Unless you really want a new car, I would just try to drive efficiently.

I am in no way a shining light in this respect as I have two sports cars (but no other), so I can only comfort myself in saying that both will last, more or less, for as long as anyone cares to keep them, so the end-of-life and disposal issues should not arise.

[Shallot Man]

Our Masters in Europe keep on about the environment, this is from an establishment that every three months, four times a year, move house from Strasbourg - to Brussels and back again.

[Chantal]

I have a 24 year old car (AJay) who runs on petrol and I am sure is not particularly energy efficient; in fact my boss calls her "Pollutinus Maximus" (but he's just jealous because she doesn't break down like his newer models). I have considered buying a newer, more environmentally friendly, car but have decided that only using her when necessary is a better option all round. How much of a carbon footprint is created by building a new car, compared to my minimual usage of AJay?