Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

Sustainable Energy

Hybrid Power Could Help Drone Delivery Take Off

A prototype hybrid quadcopter can fly several times farther than conventional battery-powered ones.

The use of small, inexpensive drones is limited by the efficiency of their engines.

Google, Amazon, and DHL are working on drones that could someday deliver packages straight to your doorstep. Unfortunately, most drones would struggle to carry something as heavy as a textbook more than a dozen kilometers on battery power.

A new hybrid gas-electric aircraft could make drone delivery more practical. Developed by a startup called Top Flight Technologies, the six-rotor drone can fly for more than two-and-a-half hours—or 160 kilometers—carrying a payload weighing nine kilograms.

The aircraft’s range is many times that of any quadcopter on the market—the most popular type of drone for its maneuverability. Almost all quadcopters run on batteries, and can fly for only about 40 minutes between charges with a payload weighing just a couple of kilograms. The new drone can also fly more than twice as far as a radio-controlled, gasoline-powered helicopter of similar size.

Top Flight’s technology is distinct from what’s being developed by Google. The Google aircraft takes off vertically but then reorients itself and flies like an airplane. But the company isn’t saying much about how far the prototype drones can travel or how much they can carry. And demonstrations of the aircraft in Australia involved delivering relatively lightweight packages, such as dog treats, vaccines, and a first-aid kit.

The efficiency of Top Flight’s drone is made possible by using batteries to supplement the gasoline engine. Power can come from the batteries, from a gasoline generator, or from both at once. And because the gasoline engine doesn’t have to supply all of the power, it’s possible to use a much smaller and more efficient one. Unlike a hybrid car, however, Top Flight’s drone doesn’t capture energy from braking.

Top Flight isn’t the first to try hybrid technology with drones. The U.S. Army and Air Force, together with an Oregon-based company called Northwest UAV, have experimented with hybrid airplanes. A representative of Northwest UAV says the company is also working on a hybrid system for use with multi-rotor craft such as quadcopters.

Top Flight was founded and is advised by researchers from Draper Laboratories and MIT. It has selected a relatively simple type of hybrid engine, known as a series hybrid, in which there is no mechanical connection between the gasoline engine and the rotors. The engine serves only as a generator that charges the battery or supplies electricity to the electric motors. Long Phan, cofounder and CEO of Top Flight, says “future vehicles will fly well over three hours—we already have the new engine to do it.” The company is also developing object-avoidance technology and other safety features—which likely will be required for drones, at least in the United States (see “FAA’s Caution Not the Only Obstacle for Drone Delivery”). Phan says the company hopes to start selling its hybrid drones by the end of the year.

Tech Obsessive?
Become an Insider to get the story behind the story — and before anyone else.

Subscribe today

Uh oh–you've read all of your free articles for this month.

Insider Premium
$179.95/yr US PRICE

More from Sustainable Energy

Can we sustainably provide food, water, and energy to a growing population during a climate crisis?

Want more award-winning journalism? Subscribe to Insider Plus.
  • Insider Plus {! insider.prices.plus !}*

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus the digital magazine, extensive archive, ad-free web experience, and discounts to partner offerings and MIT Technology Review events.

    See details+

    What's Included

    Unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

    Bimonthly print magazine (6 issues per year)

    Bimonthly digital/PDF edition

    Access to the magazine PDF archive—thousands of articles going back to 1899 at your fingertips

    Special interest publications

    Discount to MIT Technology Review events

    Special discounts to select partner offerings

    Ad-free web experience

/
You've read all of your free articles this month. This is your last free article this month. You've read of free articles this month. or  for unlimited online access.