Drones

Delivery drones will use 10 times more energy than vans around town

Delivery drones will use 10 ti...
Delivery drones don't stack up in terms of energy consumption compared to ground vehicles in most circumstances
Delivery drones don't stack up in terms of energy consumption compared to ground vehicles in most circumstances
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Delivery drones don't stack up in terms of energy consumption compared to ground vehicles in most circumstances
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Delivery drones don't stack up in terms of energy consumption compared to ground vehicles in most circumstances
Total well-to-wheels energy consumption categorized by traffic conditions, radius of customer area, and number of customers per stop (at medium wind conditions)
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Total well-to-wheels energy consumption categorized by traffic conditions, radius of customer area, and number of customers per stop (at medium wind conditions)

As soon as there were drones, there were visions of drone deliveries. Robotic insects bringing parcels and pizzas to your front or back doorstep in a jiffy, not waiting for traffic lights and traveling as the crow flies. But as aviation regulators around the world work with the likes of Amazon, UPS and DHL to clear a legal pathway for these kinds of services to begin, a new study out of Germany points out that the high energy cost of flying drones could make them worse for the environment than vans.

Multicopter drones are a marvelous technology, but as aircraft, they're highly inefficient. Lacking wings, which can develop lift by moving forward through air, drones must constantly provide upward thrust just to keep themselves airborne. Add the weight of your grande burrito delivery, and they've got to pull even harder, and energy consumption goes up considerably when they've got to fly into a headwind or crosswind. Not to mention, they can only carry one parcel at a time, making every trip a round trip of its own.

Researchers from the Martin Luther Universitat in Halle-Wittenberg have run the calculations on urban and rural deliveries, comparing drones against diesel and electric vans, and made some surprising discoveries. Based on simulations run on Berlin and the surrounding areas, the researchers found that in dense urban areas, electric vans are by far the most energy-efficient delivery option. Diesel vans use around five times more energy in this situation, and drones use around 10 times as much .

Population density is the key factor here; vans can carry literally hundreds of items at a time, and when delivery routes are short and packed with lots of drop-offs, minimal energy is wasted. The figures above assume that the vans are carrying 100 parcels each, and that all parcels weigh 2.5 kg (5.5 lb), among other things.

Total well-to-wheels energy consumption categorized by traffic conditions, radius of customer area, and number of customers per stop (at medium wind conditions)
Total well-to-wheels energy consumption categorized by traffic conditions, radius of customer area, and number of customers per stop (at medium wind conditions)

Interestingly, once you move into sparse rural areas, the drones begin to even things up. With significantly further to travel between stops, the vans lose most of their energy advantages. When customers are up to 8 km (5 mi) away from the delivery center and wind conditions are ideal, drones become more efficient than diesel vans for single deliveries.

Naturally, energy usage isn't the only thing to consider; there's the cost of staffing, the fact that electricity generation creates less pollution than diesel automobiles, driver pay rates, maintenance, downtime for battery charging and many other factors. But on a purely environmental analysis it seems electric vans are by far the best solution for getting a lot of things to a lot of tightly packed places, efficiently and quickly.

The study is available on Science Direct.

Source: Martin Luther Universitat

14 comments
paul314
If the mechanics of the problem could be handled, drones might be most useful for the last-100-meters leg of delivery routes. Instead of the laborious bit about parking, turning off the van, driver getting out, walking to the door, then restarting the van (and we know that stopping and starting engines can be particularly bad for pollution) you would just have a van that slowed down while the drone did its job. (You'd need either another person aboard or a some kind of device and packing scheme, but it still might be more effective.)
Alexander Lowe
It ought to be fairly straightforward to convert urban delivery van fleets to fully electric drive. This is likely to happen, as more cities impose tihter emissions regulations, in pursuit of better air quality.
Drone deliveries, except in remote places, seem like another complex solution to a relatively simple logisitical problem. Their biggest benefit is likely to be to the shareholders of the tech companies developing them, and the law firms and lobbyists clearing a path for their implementation.
piperTom
It's great that we can do analyses of this sort, despite --as author noted-- many contributing factors left out. However, if we could just manage to avoid giving subsidies to any of the methods (which would include hidden subsidies like waste disposal and pollution dispersal), then the price structure would immediately give us the answer: yes, the cheapest is the best. Sadly, many subsidies are deeply embedded in the economy. Trying to eliminate them is a worthy but distant goal.
Cody Blank
Any quad pilot could have told you that. Multirotors are INCREDIBLY inefficient
Zerozen
The energy cost negligible if you charge from a nuclear power source grid. No C02 complaining.
Matt Freie
Good thing there are hybrid drones with fixed-wing and rotors.
Matt Freie
Just look up the wingcopter and UPS partnership
Ben Franklin
Well the cool thing is, if you look at the drones that are being developed by Amazon, for instance, they're essentially VTOL gliders. Efficiency is a key part of the developmental process for these drones which means they'll tend to be much more eco friendly than the multicopters mentioned in the article. In the future I won't have to feel so guilty when I realize I'm out of Charmin and have to spend an extra 20min sitting on the throne playing Candy Crush until my rescue drone arrives!
CarolynFarstrider
I’m not sure why this is surprising; it seems rather obvious. But add into the mixture the noise from hundreds of drones each carrying a pizza, or something else equally inessential, and you start to understand what ‘environmental damage’ might amount to.
Nuclear power, btw, is not carbon neutral, unless you can explain the embedded carbon in the structures and the carbon emissions involved in ‘disposal’, monitoring and everlasting storage of spent fuel rods.
Trylon
This is hardly a surprise. Despite its long history of use in human civilization, the wheel is still the most energy-efficient mechanism for moving things around. Even if drones had wings, they would still have to use far more energy to maintain airspeed to stay aloft. Note for instance that a bicycle rider can do over 500 miles in 24 hours, but it took an Olympic racer to set a 71-mile distance record in a human-powered plane. Meanwhile, human-powered helicopters can hover for not much more than a minute at a time.