Methodology for determining ecological benefits of advanced tolling systems

Abstract

Toll plazas are places on the road network where increased emissions of exhaust gases occur due to changes in vehicle driving regime in their corresponding impact areas. Therefore, they provide a great potential in terms of the ability to significantly reduce the emission of pollutants by using advanced technologies. In light of this, this paper aims at getting the most accurate quantification of pollutant emission (CO, CO2, HC and NOx) for the various vehicle categories which use Manuel System (MS), Electronic toll collection (ETC) with mechanical barriers and Multi Lane Free Flow (MLFF) system, for determining ecological benefits that can be achieved using advanced tolling systems. The measurement of the emission of harmful gases was carried out in real field conditions for the five most common classes of passenger cars, light truck and semi-trailer-truck. Vehicle speed, fuel consumption and emission of pollutants were recorded every second, in various driving processes in the impact areas of toll plazas, as well as in numerous scenarios that involve a different number of vehicles in a queue. The obtained results show that the use of the MLFF system, compared to the MS, can achieve a reduction in CO2 in the range of 25%-45% and the reduction in NOx in the range of 32%-98%, depending on the type of vehicle and the considered scenario. The case study of the tolling system in the Republic of Serbia, on a sample of 77,408,112 vehicles, has shown that moving from the existing to an advanced MLFF tolling system allows for annual ecological benefits ranging from 1,349,862 € to 1,491,391 €.

Keywords: Driving modes; Emissions of exhaust gases; Fuel consumption; Toll plazas; Traffic flow.