Vehicles Allocation for Fruit Distribution Considering CO2 Emissions and Decisions on Subcontracting

Abstract

An important problem in rural-area supply chains is how to transport the harvested fruit to urban areas. Low- and medium-capacity vehicles are used in Colombia to carry out this activity. Operating them comes with an inherent cost and generates carbon emissions. Normally, minimizing operating costs and minimizing carbon emissions are conflicting objectives to allocate such vehicles efficiently in any of the supply chain echelons. We designed a multi-objective mixed-integer programming model to address this problem and solved it via the ε-constraint method. It includes decisions mainly about quantities of fruit to transport and store, types of vehicles to allocate according to their capacities, CO2 emission levels of these vehicles, and subcontracting on the collection process. The main results show two schedules for allocating the vehicles, showing minimum and maximum CO2 emissions. Minimum CO2 emissions scheme require subcontracting and the maximum CO2 scheme does not. Then, a Pareto frontier shows that CO2 emissions level are inversely proportional to total management cost for different scenarios in which fruit supply was modified.