Reduction of CO2 Emissions in Cumulative Multi-Trip Vehicle Routing Problems with Limited Duration

In recent years, as a result of the increase in environmental problems, green logistics has become a focus of interest by researchers, governments, policy makers, and investors. In this study, a cumulative multi-trip vehicle routing problem with limited duration (CumMTVRP-LD) is modelled by taking into account the reduction of CO (2) emissions. In classical vehicle routing problems (VRP), each vehicle can perform only one trip. Because of the high investment costs of additional vehicles, organizations allow the vehicles to perform multiple trips as in multi-trip vehicle routing problems (MTVRP), which reflects the real requirements better than the classical VRP. This study contributes to the literature by using a mixed integer programming (MIP) formulation and a simulated annealing (SA) based solution methodology for CumMTVRP-LD, which considers the minimization of fuel consumption as the objective function. According to preliminary computational results using benchmark problems in the literature, the proposed methodology obtained promising results in terms of solution quality and computational time.