Modeling a green inventory routing problem with a heterogeneous fleet

This paper introduces a green inventory routing problem with a heterogeneous fleet which extends the conventional inventory routing problem by considering environmental impacts and heterogeneous vehicles. A comprehensive objective is proposed, which minimizes the sum of inventory cost and routing cost, where the latter includes driver wage, vehicle fixed cost, fuel and emission costs, in which fuel consumption and emissions are determined by load, distance, speed and vehicle characteristics. We first construct a mixed-integer program, and then conduct numerical tests to quantify the benefits of using a comprehensive objective and heterogeneous vehicles. Managerial insights are also drawn from parameter analyses.