Center for Environmental Research & Technology

The main idea of dynamic eco-driving is to provide real-time driving advice to drivers so that they can adjust driving behavior or take certain driving actions in order to save fuel and reduce emissions. The advice can be provided in various forms, including recommended driving speeds, optimal acceleration and deceleration profiles, and alerts. We have developed dynamic eco-driving technology for both freeway and non-freeway applications. The freeway-based dynamic eco-driving system provides recommended driving speed to the driver while on each segment of the freeway based on real-time traffic condition on the freeway. Results from simulation and a limited real-world experiment show that the vehicles equipped with the technology save fuel and reduce carbon dioxide (CO₂) emissions by 10-20% with little impact on travel time (less than 5%) during congestion.

The research on dynamic eco-driving for non-freeway traffic has primarily been focused on roads with traffic signals. By taking advantage of signal phase and timing (SPAT) information available through dedicated short-range communication (DSRC) between traffic signals and vehicles, a variety of applications have been developed and proposed. One of the applications is to simply provide alerts to individual vehicles entering the DSRC range that have no or little chance of getting through the intersection before the signal turns red. By doing so, these vehicles can start to coast down to a full stop sooner instead of continuing on the current speed and having to apply a hard brake at the end. Evaluation results show that the fuel and CO₂ benefits for this technology are approximately 12-14%. Taking this a step further, speed planning algorithms have been developed for vehicles traveling on signalized arterial corridors. The goal of these algorithms is to recommend driving speed that maximizes the probability of the vehicle going through signalized intersections without having to come to a complete stop. Based on initial simulation results, the fuel and CO₂ savings for the technology-equipped vehicles are approximately 12-14%, without any significant impact on the travel time.