Emissions vs. Travel Time: Simulative Evaluation of the Environmental Impact of ITS

We discuss the need for taking the environmental impact as a primary metric for evaluating the quality of algorithms for Intelligent Transportation Systems (ITS). In many studies, the travel time, or its minimization, has been used to demonstrate the advantages of Inter-Vehicle Communication (IVC) solutions combined with dynamic rerouting. Such evaluations are frequently based on simulation experiments. Recently, much progress has been achieved in this domain by coupling network simulation with road traffic microsimulation. We now investigate the relationship between different metrics used for the evaluation, in particular the environmental impact represented by gas consumption and emissions versus the travel time, highlighting cases where both metrics are conflicting.