Modeling of vehicle CO2 emissions and signal timing analysis at a signalized intersection considering fuel vehicles and electric vehicles

Background: An intersection is an area with more energy consumption and emissions by motor vehicles, and the energy consumption and emissionsof vehicles at intersections should be reduced in road planning and traffic control to improve the urban traffic environment. Objectives: In order to analyze the influence of signal timing on CO2 emission of traffic flow under the mixed traffic environment of fuel vehicles and electric vehicles. Methods: A set of CO2 incremental emission models is established to estimate the CO2 emissions of fuel vehicles and electric vehicles at signalized intersections. Then, a signal timing model with minimum CO2 emissions is established, and the influence of signal timing with minimum CO2 emissions on vehicle control delay and stop rates under different traffic conditions is analyzed. Conclusions: The case study shows that optimizing of the timing parameters of intersections from the perspective of vehicle CO2 emissions is different from the perspective of control delay or stop rate; the model's timing optimization will effectively balance the CO2 emissions generated by vehicles during the acceleration, deceleration and idling stages, essentially achieving a comprehensive consideration of vehicle control delay and stop rates. When the road section speed and the mixed proportion of electric vehicles are low, the timing results tend to reduce the vehicle delay at intersections, but when the road section speed and the mixed proportion of electric vehicles are high, the timing results tend to reduce the vehicle stop rate.