Why Amazon's drone delivery service could be dead on arrival

Amazon chief Jeff Bezos recently revealed the online retail giant is trialing the use of unmanned drones to deliver packages weighing up to 5lbs to customers.

The delivery method, dubbed Prime Air, is not expected to be introduced for another four-to-five years, but to be brutally honest - I think it's probably one of the dumbest ideas I've heard in years.

It's clearly been a great marketing ploy for Amazon because so many people have been talking about it. However, from a practical point of view, it's completely unworkable.

For a start, how will the drones be powered? In these modern times you have to assume it will use some sort of battery, but how long will that last?

Anyone who's ever had a radio controlled helicopter for Christmas will tell you that you're lucky to get 15 minutes of flying time. And that's without any payload.

As soon as you try to add attach Lego figures, for example, the device's time in the air will drop even further. How on earth will it cope with a DVD or even Amazon's original raison d'etre, a chunky book?

The reason Amazon can do what they do is because they have huge warehouses in the middle of nowhere. Are these drones really going to be able to carry their payload hundreds of miles to be delivered?

While economies of scale make their business plan work, they're forgetting postal delivery is a natural monopoly that only works because of economies of scale.

Furthermore, how is delivery going to be accomplished? Where will the drones drop the parcels? How will people sign for them? How will it work in flats, or if the recipient isn't home?

All of these questions make the idea a non-starter for me. I'd gladly take a 50 pence wager with Bezos that it doesn't happen within 10 years.

That being said, talking about ideas like this may lead to innovation. How about using something along the lines of Google's automated car? This would obviously be driverless but also allow more than one package to be carried at once.

If you had a keypad, for instance, on the car for the recipient to enter a code on and get it released. This would be akin to signing for the package.

This doesn't solve every problem, but is possibly a more workable solution in the long term.