Estimating energy consumption for routing algorithms

Due to increased public discussion on global climate change and increased awareness of environmental issues in general, a variety of transport related strategies are being developed to reduce the energy consumption of road travel. Pre-trip journey planners and on-trip navigation systems are widely used to identify optimal routes. Travel time, trip distance and travel cost are usually used as criteria to search for the best route and suitable alternatives. However, energy use could also be used as a criterion in these systems to identify energy minimizing routes will be one measure to reduce fuel consumption. In order to identify these ”eco-friendly” routes, the energy consumption for each link of a network must be computed quickly and precisely. This paper presents an approach for calculating link energy consumption based on the actual power needed to overcome the driving resistance for each link using link travel speeds and v/c-ratios. The proposed method can be embedded in routing algorithms and be used as one component in the optimization of the route algorithm´s generalized cost function.