What is the environmental impact of drone delivery, now that companies are looking for ways to decarbonize transportation? 

Drone delivery company Zipline recently published the results of a sustainability analysis of its UAS logistics system that uses drones for medicine deliveries. The study compares monthly CO2 delivery emissions with transport modalities such as cars, light goods vehicles, motorcycles, and electric vehicles. Ziplines claims the analysis is the “world’s first sustainability analysis of a real-world, called UAS logistics system’s deliveries based on actual customer and order data”, finding a 98% reduction in delivery emissions compared to using cars. 

The analysis, titled “The Sustainability of Zipline’s Autonomous Aerial Logistics”,  explains how Zipline delivers last-minute medicine deliveries to hospitals, medical facilities, and patients within 80 km of one of its centralized medical warehouses and distribution centers. The goal of the analysis is to identify the sustainability difference between its Zipline network and an equivalent ground-based delivery network. 

Drone delivery and its environmental impact 
While such analysis is necessary and informative, it only covers a single use case (last-minute delivery) in a limited area (Rwanda). It is doubtful that the results from the analysis are 100% transferable to other geographic regions and use cases. What makes this analysis relevant is that it makes a strong argument for sustainability, which is shared more broadly now that the effects of climate change are noticeable in many ways. 

One example is drone-delivery network builder Aerialoop. In November 2024, the Florida-based company published an article outlining its sustainable vision for drone delivery and its environmental impact. For example, its VTOL drones, powered by clean, battery-operated systems, present a viable alternative to the environmental burden of traditional delivery methods. 

Geographically, Aerialoop focuses on densely populated cities where delivery volumes are increasing due to e-commerce. Its drone delivery networks operate in dedicated air corridors, bypassing congested roads and alleviating the pressure on ground infrastructure. Aerialoop sees sustainability not just as a goal, but as a responsibility: drone technology is instrumental in creating cleaner, greener cities. 

A more balanced view on the environmental impact of drone delivery 
Constantine Samaras and Joshuah Stolaroff  present the most thorough analysis of drone delivery and sustainability. Both researchers published an article with the results of different models that compare emissions from different transport modalities in the US, including drones, trucks, and vans. The title gives away the most important conclusion: “Delivering packages with drones might be good for the environment”. 

The main conclusion of both researchers is that in some cases using electric-powered drones rather than diesel-powered trucks or vans could reduce energy use and greenhouse gas emissions. In other cases, trucks would be more efficient and cleaner (especially electric-powered ones). 

Put differently, drones are not always the “best” (or most sustainable) option. This has a lot to do with the type of drone used (along with its payload), which is related to the amount of energy a drone uses. They also point out that while a drone using batteries is cleaner than burning fuel, making batteries still generates carbon dioxide. 

They also make a valid point for allocating the energy needs and environmental effects per package instead of a single electric drone or heavy steel delivery truck burning diesel fuel. While the first one uses much less energy per mile than the second one, it cannot carry that many packages. The authors state that drone delivery requires transportation in multiple legs due to the drone’s range. This would require opening new warehouses, which also use electricity and potentially natural gas to operate. These new warehouses in a way nullify the sustainable gains of drone delivery, and it explains why for large packages, it’s probably better to use electric vans or trucks instead of large drones (the emission savings are more obvious for small drones compared to any truck or van). 

Drones for last-mile delivery 
Sustainability Magazine published an article on how Walmart uses drones to deliver packages to customers. At the time of publication, Walmart served seven states by drone delivery across the US. The company has set goals to decarbonize its operations and expand access to clean energy for customers and suppliers by 2040. Drone delivery offers both customer benefits and helps the company tackle carbon emissions. Similar to Zipline’s use of drones, Walmart sees potential for drones in last-mile delivery, such as last-minute grocery runs which are the most common reason for unplanned car trips, according to 43% of Walmart’s customers. 

This article outlined recent and less recent findings on the sustainability effects of drone technology. A common finding among these publications is that the sustainability effects are most obvious for smaller drones when used for last-mile delivery. With other logistics firms and retail companies such as FedEx, DHL, and Amazon turning to drones to deliver packages to customers, exactly this type of drone delivery will continue to grow.