An Alternative Approach for Solving the Environmentally-Oriented Discrete Network Design Problem

This paper addresses the discrete network design problem (DNDP) with emphasis on the environmental benefits. These benefits are traditionally quantified by emission models, which in general account for vehicle speeds, traffic flows and emission coefficients. An alternative approach for approximating the environmental impact of traffic is developed. This approach finds the route that keeps the most balanced speed profile throughout the route, which contributes to fuel consumption reduction. The paper formulates an optimization problem that includes the described approach for the DNDP. The solution of the problem consists of projects that contribute the most to the generation of such “balanced speed routes”. The paper illustrates the problem and the solution for a real-size network with a medium-size set of candidate projects.