The use of delivery drones, unmanned aerial vehicles capable of delivering small and light packages, has garnered interest in for the last-mile segment of the freight logistics community. The use of delivery drones may augment, or even replace the use of trucks for delivery, which can have impacts on energy consumption, congestion, and road network usage patterns. Researchers conducted a study to develop a simple simulation of the total energy-use impact in Minneapolis of shifting some package delivery stops, for deliveries weighing five pounds or less, from traditional delivery trucks to delivery drones. The reduced number of stops could allow for changes such as a smaller truck fleet delivering to fewer service areas. A geographic information system (GIS) analysis was used to compare truck versus delivery drone energy use. This preliminary study uses a limited data set derived from a National Renewable Energy Laboratory (NREL) study of conventionally powered and hybrid delivery vans in Minneapolis.
The research team digitized a map of 13 delivery routes in the Minneapolis metropolitan area taken from the NREL study, characterized the delivery districts, created a comparable set of districts covering a 10-mile radius from the center of the city using a cluster library in the Python computer programming language. The team calculated the miles driven and gallons of diesel required to deliver packages by truck to those districts, assuming 90 daily stops on average per delivery truck. Then, a hypothetical set of delivery points within these districts was created, and 20 percent of those points, representing the lightest weight packages, were assigned to be serviced by drones. The drone miles and energy required to make these deliveries were calculated. Next, the research team created a new set of zones to reflect the 20 percent fewer stops made by the delivery trucks, and repeated the mileage and diesel consumption estimates for these areas. The electricity required by the drones was estimated and expressed in terms of its energy equivalent in diesel, 460 miles per gallon equivalent. Finally, the estimated energy used by trucks and drones were combined to produce an estimate of total energy consumption under the scenario with 20 percent drone deliveries.
- If 20 percent of stops involve delivery of packages weighing 5 pounds or less, shifting the servicing of these stops to drones from trucks could save as much as 5.7 percent of the total energy used to deliver packages within 10 miles of the center of Minneapolis.
- Researchers found that the 20 percent drone scenario would require 13 fewer truck routes, 468 fewer truck miles, and 46.8 fewer gallons of diesel fuel, assuming an efficiency of 10 miles per gallon (MPG) for trucks, consistent with the NREL data.
- Although the analysis used estimated values based on energy equivalency of diesel fuel to demonstrate the savings of using drone-based deliveries, the drone energy use would be entirely electric, generating a much lower carbon footprint than traditional trucks and producing less local air pollution.