Increased E-commerce and demand for contactless delivery during the COVID-19 pandemic have fueled interest in robotic package delivery. We evaluate life cycle greenhouse gas (GHG) emissions for automated suburban ground delivery systems consisting of a vehicle (last-mile) and a robot (final-50-feet). Small and large cargo vans (125 and 350 cubic feet; V125 and V350) with an internal combustion engine (ICEV) and battery electric (BEV) powertrains were assessed for three delivery scenarios: (i) conventional, humandriven vehicle with human delivery; (ii) partially automated, humandriven vehicle with robot delivery; and (iii) f ully automated, connected automated vehicle (CAV) with robot delivery. The robot’s contribution to life cycle GHG emissions is small (2−6%). Compared to the conventional scenario, full automation results in similar GHG emissions for the V350-ICEV but 10% higher for the V125-BEV. Conventional delivery with a V125-BEV provides the lowest GHG emissions, 167 g CO2e/package, while partially automated delivery with a V350-ICEV generates the most at 486 g CO2e/package. Fuel economy and delivery density are key parameters, and electrification of the vehicle and carbon intensity of the electricity have a large impact. CAV power requirements and efficiency benefits largely offset each other, and automation has a moderate impact on life cycle GHG emissions.
CSS Publication Number:
last-mile ground delivery
life cycle assessment
greenhouse gas emissions
Environmental Science and Technology
July 30, 2021
Li, Luyao, Xiaoyi He, Gregory A. Keoleian, Hyung Chul Kim, Robert De Kleine, Timothy J. Wallington, Nicholas J. Kemp. (2021) “Life cycle greenhouse gas emissions for last-mile parcel delivery by automated vehicles and robots.” Environmental Science and Technology XX(XX): 1-XX.