Using Connected Vehicle Technology to Implement a Pay for Priority System at Signalized Intersections
Congestion is a major mobility problem on the road network. Adding physical capacity may not be a viable option, often for financial reasons. Adaptive signal timing is one approach to optimizing mobility on corridors with signalized intersections. One approach to increasing funding for transportation projects is the introduction of additional user fees. This study evaluated a mixed vehicle environment, both connected (CVs) and non-connected vehicles, where connected vehicles could pay a small fee ($0.00356 to $0.01422 per request) to request priority at a signalized intersection.
Connected vehicles with signal priority capabilities were simulated using VISSIM with CV penetration levels ranging from 10 to 100 percent on two corridors in Clemson, South Carolina. The scenarios were compared to optimized signal timing to determine the effectiveness of the technology in terms of average delay. A benefit-to-cost analysis was performed for the major flow direction priority scenario, because it was the only scenario to out-perform the optimized signal timing scenario with no CVs.
Connected vehicles with signal priority experience less delay than non-connected vehicles for all priority direction scenarios up to a certain point, about 20 percent. When all directions and major street movements in both directions are allowed to request priority, the advantage for CV was statistically significant at up to 20 percent CV penetration. When priority was only allowed to be requested in the direction of highest flow, CVs experienced lower delay at a statistically significant level at up to a 40 percent CV penetration level. Above these thresholds, all connected and non-connected vehicles experience similar delay.
The benefit-to-cost analysis based solely on revenue generated from CV requesting priority at intersections yielded a benefit-to-cost ratio of greater than 1 at a 20 percent CV penetration rate. With the benefit-to-cost analysis added the benefit of decreased network delay for all vehicles, benefit-cost ratios up to 3 were observed at 10 percent CV penetration levels.