Calculate annual car emissions and compare fuel types.
Petrol emits about 2.31 kg of CO2 per litre burned, a fixed figure set by its carbon content. Electric vehicle emissions depend entirely on the grid, so the same car is nearly clean on a low-carbon grid and comparable to a hybrid on a coal-heavy one. Occupancy is the largest lever available without changing vehicle: four people sharing emit a quarter each of the same journey driven alone.
Car Emissions
Emissions = distance × consumption ÷ 100 × emission factor for the fuel
Emissions = distance × consumption ÷ 100 × emission factor for the fuel Petrol emits about 2.31 kg of CO2 per litre burned, a fixed figure set by its carbon content. Electric vehicle emissions depend entirely on the grid, so the same car is nearly clean on a low-carbon grid and comparable to a hybrid on a coal-heavy one.
Occupancy is the largest lever available without changing vehicle: four people sharing emit a quarter each of the same journey driven alone.
This calculator takes 5 inputs: Annual distance driven, Fuel type, Consumption per 100 km, Grid carbon intensity, Average occupants. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.