Companies from Amazon to Walmart to DHL are exploring how to make drone deliveries a reality, but truck deliveries are still the most environmental friendly way of getting goods to customers.
Research by University of Washington (UW) has found that while drones may be able to reduce carbon dioxide emissions when they don’t have to fly very far or when a delivery route has few recipients, trucks are still a more climate-friendly option when a delivery route has many stops or is farther away from a central warehouse.
In the past few years lots of work has been put into making drones light and durable enough to perform deliveries, but, according to the research, it may be time to put that same emphasis into engineering lightweight trucks.
“We haven’t applied the same level of effort to engineering lightweight trucks — they’re excessively heavy and the on-road fleet doesn’t look much different than it did a few decades ago,” said UW associate professor of civil and environmental engineering, Anne Goodchild.
“If we took the same amount of energy we’ve put into making drones light and efficient, applied that to trucks and got them on the street, we could do so much good for the transportation industry and the environment.”
While public debate has largely focused on cost reduction, privacy implications and airspace congestion, few people have analysed the environmental consequences that drone technology may have if fully adopted by industries.
The UW’s testing compared carbon dioxide emissions and vehicle miles travelled from drone and truck deliveries in 10 different, real-world scenarios in Los Angeles.
The analysis also assumed that drones could carry only one package at a time and would return to a depot after each delivery — requiring far more back-and-forth and vehicle miles travelled than for an equivalent truck route.
“Flight is so much more energy-intensive — getting yourself airborne takes a huge amount of effort. So I initially thought there was no way drones could compete with trucks on carbon dioxide emissions,” said Goodchild.
“In the end, I was amazed at how energy-efficient drones are in some contexts. Trucks compete better on heavier loads, but for really light packages, drones are awesome.”
The researchers concluded that it’s unlikely that drones will be used for all delivery applications, but a scenario could exist where a truck hauls an entire load of packages to a centralized location, and then a fleet of drones fans out in opposite directions to reach individual homes or businesses.
“Given what we found, probably the most realistic scenario is for drones doing the last leg of the delivery,” said Goodchild.
“You’re probably not going to see these in downtown Seattle anytime soon.”