Signalized intersection with real-time adaptive control: on-field assessment of CO 2 and pollutant emission reduction

Abstract

The environmental costs linked to an isolated signalized intersection have been quantified in terms of CO 2 emission, fuel consumption and standard pollutant emission. A multi-camera system automatically estimates vehicle idle time and stop rates per itinerary; each vehicle is affected a cost that depends on whether it stops at least once and on its idle time on red. Elementary costs are calibrated using real urban driving cycles and their corresponding emission profiles measured on test benches. These experimental data are used to calibrate average coefficients for catalyst converter gasoline vehicles, non-catalyst ones and diesel vehicles (passenger cars). An on-field experiment was performed during 8 months to evaluate the benefits of the CRONOS control strategy, compared to a time plan strategy with vehicle actuated ranges. The benefits observed have shown the potential of this adaptive real-time control strategy that uses video traffic sensors. Large benefits on stops and delay induce significant reduction in environmental damage: 4% reduction for CO 2 emission in peak traffic whatever the type of engine, which corresponds to 14% reduction on the part of costs due to stops and delay. Such figures show that environmental costs can be reduced without giving up fluidity benefits.