Simulations to reduce emissions from road transport

The research result conducted by the School of Engineering of the Universidad Politécnica de Madrid (UPM) is a model system that allows the simulation of future cases of greenhouse gas and air pollutants emissions from vehicles. This proved how difficult is to implement measures that could help simultaneously reduce both types of emissions.

The emission problems of greenhouse gas and air pollutants are the big challenges of road transport today. Its contribution to climate change and the low urban air quality are the main reasons why road transport increase is currently being limited.

Researchers of the Environmental Technology and Industry Resources group have developed a methodology that can calculate the emissions of an area transport fleet, taking into account vehicle types and environmental laws of that area.

Therefore, this simulation model can assess the impact of policies and measures such as support systems for vehicle renewal, speed reduction, market penetration of less powerful engines, vehicles fuel change, the city circulation restriction policy and the biofuel usage awareness.

This model system was successfully conducted in Spain by calculating emission projections until 2020 in diverse situations. The conducted tests show that reducing the greenhouse emissions requires mostly non-technological measures (mobility restriction). However, the renewal of the vehicles fleet with systems of advanced emission reduction is the most efficient option to reduce emissions of air pollutants (mainly nitrogen oxides and particulate matter).

Researchers also conducted a sensitivity analysis to identify the most influential variables in future emissions. The obtained values show that the link among petrol and diesel cars and the vehicles age are decisive variants for nitrogen oxide emissions. On the other hand, speed on highways and the vehicle engine type are the most influential factors that contribute to CO₂ emissions.

This research shows the difficulty to implement measures to reduce simultaneously both greenhouse emissions and air pollutants on road transport. This research suggests studying the side effects of these measures before putting them into practice.