Strasbourg has become the first city in France to optimize its traffic signal control system in order to improve air quality and reduce vehicle emissions by reducing stop-and-go traffic.
As part of the French Air Pollution Control program that was introduced in 2015, authorities for Strasbourg’s greater metropolitan area (Eurométropole) and the region’s air pollution control authority AtMO Grand Est employed the German transportation software developer PTV Group to conduct analysis of the city’s traffic network.
The study found that the sheer volume of vehicles and large number of intersections controlled by traffic lights or stop signs was creating stop-and-go traffic, leading to higher emissions caused by stationary vehicles.
PTV then used its Vissim software tools to simulate and illustrate the potential benefits of deploying the company’s Epics adaptive traffic control system as an air pollution control measure. The Strasbourg simulation revealed that by using the Epics system:
• Vehicle stops could be reduced by 9%;
• Nitrogen oxide emissions (NOx) could be cut by 8%; and
• Particulate matter (PM10) pollution could be lowered by 9%.
The simulation results were so convincing that the project is now entering the next phase, with field tests of the Epics software now being carried out along one of the city’s main arterial roads. The PTV system has now been integrated into FARECO’s control units installed at the junctions along the Avenue de Colmar.
The model-based Epics process observes local conditions in real-time and calculates numerous control options every second. The system takes all modes of transport into account, from individual motorized transport and pedestrians, to prioritizing public transport at junctions. If the simulation results are confirmed in practice, the city authorities want to install the signal control system at further road sections.
“Our Epics software helps optimize signal control programs in order to minimize waiting times at traffic lights and thus reduce the number of stop-and-go waves,” explained Frédéric Reutenauer, project officer and VP for project management and services at PTV.
“We used the Vissim traffic simulation software to visualize the effect on traffic by analyzing the flow at six signalized intersections of Avenue de Colmar. The waiting time for all road users at traffic lights controlled by our Epics software tool was below 45 seconds in 85% of all cases.
“Currently, this only applies to 35%. I’m confident that we will also obtain convincing results during the field tests. The test phase is expected to last until summer. It will then be defined in which additional areas this new technology should be rolled out.”