Multi-depot mixed fleet joint distribution routing optimization with partial recharging strategy

In the scenario of mixed transportation of electric vehicles and fuel vehicles in urban logistics, there are shortcomings in the joint optimization of transportation resource sharing and recharging strategies. Therefore, this paper comprehensively considered practical factors such as customer time windows, mixed fleet, partial recharging strategy for electric vehicles, multi-depot joint distribution mechanism and carbon emissions, and investigated a multi-depot mixed fleet green vehicle routing problem with partial recharging and time windows. An optimization model was established with the objective of minimizing the total cost, including vehicle fixed costs, transportation costs, charging costs, carbon emissions costs, and time penalty costs, and a hybrid improved genetic algorithm with variable neighborhood search was designed to solve the model. A simulation experiment using actual data from a logistics enterprise in Hunan Province was conducted to verify the effectiveness of the above model and algorithm. Sensitivity analysis was performed on three aspects: distribution mode, fleet configuration, and charging strategy. The results are shown as follows. (1) Joint distribution mode can help to strengthen the collaborative cooperation between distribution centers, promote the sharing and scheduling of transportation resources, reduce logistics distribution costs and carbon emissions, making it an economically and environmentally friendly distribution mode. (2) Excessive charging time for electric vehicles will affect customer satisfaction with time, and this effect is more significant for pure electric fleets. (3) Compared to pure electric fleets, mixed fleets have lower distribution costs and higher customer satisfaction, and have more advantages in reducing distribution costs and carbon emissions compared to pure fuel fleets. Rational fleet configuration can not only reduce the operational costs of enterprises, but also balance the interests of both customers and the environment. (4) Adopting partial recharging strategy in logistics distribution can effectively save charging time and improve customer service experience. The study can provide reference for logistics enterprises to make decisions on joint scheduling of transportation resources and optimization distribution plans. © 2024, Central South University Press. All rights reserved.