I posted this in another thread on the matter of carbon footprints- Further browsing of the stastics give the figure of 262g/km exhaust emmisions and fuel consumption of 9.2 litres per 100km http://www.whatgreencar.com/view-car/7414/land_rover-discovery_series_ii-2_5_TD5 That means (on these figures) my Discovery burns 83 grams of fuel per km. How does my car burn 83 grams of fuel yet produce 262 grams of CO2 emmisions per km? I know the CO2 is a gas but it is measured in weight on the emmision figures. I'm genuinely puzzled, in truth I couldn't care less how much CO2 it produces. All it does is feed the plants! I'm being taxed on my usage based on these figures and I would like to know what they are supposed to mean. Any of the boffins here on Arrse able to explain it to me please?