The Sustainable Parcel Delivery (SPD) Problem: Economic and Environmental Considerations for 3PLs

Abstract

Sustainability in parcel delivery is a growing area of interest, especially for third-party logistics providers (3PLs). The recent increase of urban population is directly related to the increase request of goods in urban areas, and consequently to the growth of the urban freight transport and CO2 emissions. For these reasons, national and local institutions carried out regulations and incentives to reduce urban pollution and promote zero-emission vehicles. In particular, daily tickets to access to city centers is a common regulation applied to reduce freight transport. This paper presents a new SPD model that compares Eclectic Vehicles (EVs) and Fossil Fuel Vehicles (FFVs) considering economic savings and CO2 emissions, for parcel delivery from a single distribution center to a set of delivery point located inside and/or outside an urban area. Limitations as the daily ticket, the fuel cost, the battery duration are considered to provide 3PLs an innovative model to evaluate both the economic convenience and the environmental impact of its vehicles fleet. Through an explanatory study, economic considerations are carried out, related to the length of the route, the daily ticket cost, and the fuel cost to evaluate and to assess the different transportation options. It demonstrates that EVs are more convenient in terms of economic savings when the route (urban distances) and the daily ticket cost increase.INDEX TERMS Electric vehicles, mixed fleet routing, economic saving, environmental saving, sustainable parcel delivery.

An Enhanced Delivery Route Operational Planning Model for Electric Vehicles

“…A multi depots capacitated EV routing problem is proposed in [30], which is solved using a heuristic algorithm that combines Variable Neighborhood Search and Space Saving. In [31], a new sustainable parcel delivery model that compares EVs with conventional vehicles is studied, considering enconomic aspects and emissions. Finally, the Traveling Salesman Problem with hybrid EVs proposed in [17] has been improved in [32], including time window constraints.…”

“…It includes several real-world aspects from previous models and features modeling differences over them [12]- [32]. Note that, in [16], [21], [23]- [26], [28], [29], [31], the allocation of deliveries to each EV and the order of those deliveries is predetermined and, therefore, so is the number of EVs. In [17], [32], the allocation of deliveries is an output of the optimization process, but the number of EVs is predetermined.…”

“…Additionally, unlike [13], [17], [19]- [27], [29], [30], [32], the PA considers the battery degradation costs by explicitly modeling the operation of EV batteries depending on their life cycle, efficiency and technology. In [12], [14]- [16], [18], [28], [31], the battery degradation cost is included either as a fixed cost or not taking into account life cycle, efficiency and technology [7]. Furthermore, in contrast to [12]- [14], [16], [17], [19], [21], [23]- [32], the power consumption of the EVs is characterized in terms of not only of the distance but also the speed.…”

“…Finally, from a methodological viewpoint, rather than using heuristic and metaheuristic techniques [12], [14]- [16], [18], [20], [22], [30], [31], the proposed model is formulated as a MILP model, which guarantees finite convergence to optimality [33]. Nevertheless, the PA is considered an NPhard problem due to the high number of binary variables and possible combinations.…”

“…is at the minimum value. When several EVs reach an intersection with delivery, it is logical that the first one arriving is the one that makes the delivery, as shown in (31). Constraints (32) and (33) guarantee that t A v,i,n can take the minimum value if intersection i is passed through and the delivery is made.…”