Drones have become an integral part of today’s aerial photography. They now photograph, film, measure and even transport packages. Now researchers want to make drones even more effective thanks to hydrogen. (Image: Adobe Stock)
LiquiDrone – that is the illustrious name for a project that is somewhat reminiscent of a fat bumblebee and is intended to revolutionize aviation. We are talking about a drone that will fly using liquid hydrogen. More on that in a moment.
Cool innovation in aviation
In order not to overrun our planet, which is worth protecting, with CO₂ technology, we must urgently and quickly look for climate-neutral technologies. In our globally networked times, this of course also applies to them aviation.
There are many exciting innovations that have so far received little attention. The scientists at ZAL (Center for Applied Aviation Research) in Hamburg, for example, rely on climate-neutral hydrogen gas.
▶ The projects: Under the names ZALbatros and LiquiDrone, ZAL researchers have developed two hexacopter drones that can take off using hydrogen-based fuel cells.
▶ The advantage: When using hydrogen gas, the only end product produced is water instead of CO₂.
To give you an idea of what the ZALbatros drone looks like with its eye-catching gas bottle:
Link to Twitter content
Worth knowing: The drone has 6 rotors and a thick bottle full of hydrogen gas on its back. This is under 350 bar pressure and drives two fuel cells, which are located under the bottle and each deliver 800 W of power. Thanks to its carbon fiber hull, the ZALbatros only weighs 12 kg.
Liquid instead of gaseous – researchers see potential in this
During the flight test, the ZALbatros achieved a flight duration of two hours and ten minutes despite sometimes gusty winds. Battery-powered drones often have to land again after just over half an hour to charge or change the batteries.
Engineer Sebastian Altmann explains this to the Spectrum magazine. But that doesn’t seem to be enough for the ZAL team. To increase the flight duration, they add another one.
▶ The researchers’ goal: The LiquiDrone will soon be powered by liquid hydrogen instead of gaseous hydrogen, as is the case with the ZALbatros.
“Due to the higher energy density, such a drone could be in use for up to twelve hours.”
Sebastian Altmann, Spektrum.de
▶ Airbus is getting involved: In addition to the federal government, the University of Rostock and numerous companies, Airbus also supports research. The company wants bis 2035 develop a hydrogen-powered passenger aircraft and is therefore also interested in this flight technology.
By the way, hydrogen aircraft prototypes already exist. Already in 2016, a Europe start-up called H2Fly a four-seater passenger aircraft with a range of 1,500 kilometers – so the capacity and range are still significantly behind kerosene-powered aircraft.
In order to further develop hydrogen technology and make it more efficient, research projects like the LiquiDrone and the experience gained from them are so valuable. There are still a few hurdles to overcome when it comes to liquid hydrogen. So how realistic are commercial hydrogen propulsion for aviation?
So will we one day fly thanks to hydrogen?
In order for this liquid hydrogen technology of the drone to be suitable for series production, the team behind the LiquiDrone still has to overcome a few hurdles. A quick overview:
- Liquid hydrogen storage technology is challenging
- Regasification (liquid to gaseous for fuel cell operation)
- Control boil-off (unplanned evaporation of liquid hydrogen)
- Refueling with liquid hydrogen is difficult
- Later: Create infrastructure for liquid hydrogen for flight operations
- Scalability: In the end, the starting weight of the drone should be 500 kg (= 20 times the current weight)
For our safety, new flight technologies require safety certificates so that they can reach series production. These are very time-consuming and therefore expensive – but security has its price. So we are at the beginning of a development here.
It will therefore probably be some time before such drones are used in series production or Airbus aircraft with hydrogen engines and hundreds of passengers fly around the world.
The first test flight of the LiquiDrone with liquid hydrogen is planned for spring 2024. So we can stay excited to see how this technology will develop further.
What do you think about hydrogen technology? Could airplanes one day only fly on hydrogen? What area of application could such hydrogen drones have if they can really carry a take-off weight of 500 kg and the corresponding take-off loads? Do you know of any other useful areas of application for hydrogen that are less well known? Feel free to write us your thoughts about it in the comments.
