Greenhouses gases are becoming a more important feature in choosing a car. Not only on a personal conscience level, but also from a taxation perspective. 

Some Government information on cutting CO2 while driving can be found here.

Emissions ratings for UK cars

Previously seen on white goods and showing electrical efficiency, new fuel economy labels like the one shown on the left will be displayed on new cars being sold. This time though, they will indicate CO2 emissions and fuel consumption levels. 

From an atmosphere friendly 'A' rating (less than 100 grams per km) which can currently obtained only by some electrical vehicles, to a greenhouse-tastic 'M' rating (more than 255 grams per km) to which sadly, most decently fast cars belong, all cars will be classified and taxed accordingly. 

Company Car Taxation and Vehicle Excise Duty (Road Tax) will both be affected by these ratings also, so be warned!