Eco-routing features, designed to guide drivers on more fuel efficient routes, are now being incorporated into navigation systems. Such tools range from an indicator that highlights optimal fuel efficiency, to sophisticated eco-routing functions that employ real-time traffic data or roadway data to suggest the most efficient path to a destination based on current driving conditions. Several barriers need to be addressed before such routing algorithms can be deployed confidently. Environmental data, alternative modes, and parking availability information are not always available or integrated into navigation systems. Traffic data is often incomplete or inaccurate and is not always provided free of charge. Addressing these barriers is important for leveraging navigation systems as a means to reduce vehicle emissions.

FINDINGS

Navigation systems can provide substantial benefits for fuel economy and environmental impacts. Drivers using in-vehicle and portable navigation systems in unfamiliar locations can reduce Vehicle Miles Traveled (VMT) by 16 percent, and drivers can save up to 30 percent in mileage searching for a parking space, if the appropriate information is provided by the system. Fuel consumption and time savings are also realized through the use of real-time traffic information that helps drivers avoid traffic jams. These reductions all add up to fuel and emissions saving.