Do the CO2 emissions from petrol / gas vehicles vary depending on driving style? Are emissions a function of the engine type or the fuel efficiency?
If a motor car is rated at 105 g/km, but it is driven particularly aggressively would it actually generate 150 g/km or just 106 g/km?
If the same car is rated as getting 45 mpg, but a particular driving style, like long gentle motorway journeys, result in an efficiency of 60 mpg would the CO2 emissions be around 75 g/km or better?
If the CO2 is from the fuel, does a car idling generate more CO2 than a car moving but using the same amount of fuel?