Flying, to a layperson like me, seems like requiring quite a lot of energy (power consuming). As a matter of fact thisis not the case. An airplane is pretty thirsty on fuel but only during the take off and climbing phase. The real flight at constant altitude is not that much power expensive than driving a car, only some 10% more expensive in terms of energy. The airplane uses this extra energy to counteract the force of gravity. The airplane wings are there for that. Moving forward is way cheaper for an airplane than for a car. If you add to this the fact that a car has to follow the road, stop at signals and find its way across traffic whilst an airplane can fly as the crow flies you can see why flying is cheaper, energy wise.
However, this is not the case for drones! Drones don’t have wings and they have to use their propellers for counteracting the force of gravity. This turns out to be quite expensive in terms of energy.
Researchers at the Martin LutherUniversity in Halle-Wittenberg have made a comparison among drones, diesel vans and electric vans for delivering packages taking into account different radius of delivery and different traffic conditions.
It turns out that drones are always more energy hungry than electric vans (up to ten times more) and basically always hungrier than diesel vans (up to five times more) with the exception of single delivery in a radius exceeding 6km. In all other cases also diesel vans are more energy wise than drones.
This is something that will have to be taken into account as drone deliveries pick up. It is clearly faster, and most people will like it better, but it will also be more energy expensive. Sure, people will be willing to pay a bit more for faster delivery but that will increase the strain on our planet Earth. On the other hand, if drone delivery services will make use of renewable and clean energy for recharging the drone batteries than the extra cost may not be that important.