How are the CO2 emissions of my car calculated if I enter a license plate?
To determine the CO2 emissions of your car, we consider 2 types of emissions: direct emissions from driving the vehicle (tank-to-wheel or tailpipe emissions) and indirect emissions from producing the fuel (well-to-tank or upstream emissions).
The direct emissions are collected from the RDW when you enter your license plate. These emissions are specific for your car. The value is based on the average fuel or kWh consumption of your car, and is therefore currently not based on your driving behavior.
For the indirect emissions, we collect the fuel consumption of your car from the RDW. This is normally displayed in liters per 100 kilometers. We combine this information with information from co2emissiefactoren.nl, a website with the CO2 emissions of various fuel types and electricity. This website is created and maintained by the Dutch government, in collaboration with other research organizations. Using the fuel consumption of the car and the indirect emissions of a liter of fuel or a kWh of electricity, we calculate the indirect emissions from a car kilometer.
For hybrid cars we take a similar approach, but since the ratio between driving electric and on fuel is often unknown, these values are less accurate than those of other cars.