Abstract
This study was based on the global demand for low-carbon development. The multitrip vehicle mode is a promising approach to reduce carbon emissions in the vehicle routing problem (VRP). It was hypothesized that emission reductions might be achieved by replacing the single-trip vehicle mode with a multitrip mode. To evaluate the carbon emissions reduction potential of the multitrip mode accurately over the single-trip mode, the set-partitioning formulation was used to obtain the optimal single-trip solution VRP with the minimal carbon emissions and to construct a trip-chain-oriented set-partitioning formulation to obtain the optimal multitrip solution VRP with minimal carbon emissions. The two set-partitioning formulations could be exactly solved by CPLEX. Through a comparison of the single-trip and multitrip carbon emissions for picking up and delivering customers to an airport service, which was a special case of the VRP, it can be concluded that the multitrip mode could reduce carbon emissions by approximately 16%. To identify the situations under which carbon emissions could be efficiently reduced by replacing the single-trip mode with the multitrip mode, the influence factors were analyzed. On the basis of experimental results, a summary is provided of several managerial insights that can be used to reduce carbon emissions successfully by implementing the multitrip mode.