If trucks have to search for a parking space for a long time, often drive off and onto overcrowded parking spaces, CO2 emissions increase.
Assuming a truck leaves the motorway five times per evening for a parking space, this corresponds to approximately 10.6 kilograms of CO2, extrapolated over one year this corresponds to CO2 emissions of more than 3,000 kilograms of CO2 per year and vehicle.
This corresponds to an additional consumption of diesel of over 1,000 litres per year / vehicle.