The 11th Breakthrough Technology of 2023 takes flight
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It’s official—after over a month of open voting, hydrogen planes are the readers’ choice for the 11th item on our 2023 list of Breakthrough Technologies!
I’d like to thank the academy, and all of you, on behalf of hydrogen planes. This is an honor, a true honor. (By the way, if you haven’t seen the rest of this year’s list, check it out here.)
It just so happens there’s also some news about hydrogen planes this week. Startup Universal Hydrogen is planning a test flight for tomorrow. If all goes according to plan, it’ll be the largest aircraft yet to fly powered by hydrogen fuel cells.
So for the newsletter this week, let’s take a look at what Universal Hydrogen is up to, why its CEO says he wants to make the equivalent of Nespresso capsules for aviation, and what’s coming up next for hydrogen planes.
Aviation accounts for about 3% of the world’s greenhouse-gas emissions, and the field is growing. Most planes today run on a variation of kerosene, a fossil fuel that generates emissions when it’s burned in aircraft engines. This kind of jet fuel is hard to replace, since it carries a lot of energy in a small amount of space without being too heavy.
There are some options on the table to decarbonize flight. Batteries might work for shorter flights on smaller planes. Sustainable aviation fuels are another option—those can drop into existing planes but might be limited in supply and could be expensive. For more on these possible paths, check out the newsletter from a few weeks ago.
Here, though, let’s focus on hydrogen. Efforts to fly planes using hydrogen as fuel date back to the 1950s. Interest has been rekindled recently as concerns about climate change have put a target on fossil fuels.
Hydrogen is having a moment More capacity for renewable energy means green hydrogen—generated using renewable electricity—is becoming more available, and cheaper. New subsidies for hydrogen are also coming online across Europe and the US.
At the same time, there’s been some significant progress in efforts to fly hydrogen-powered planes in recent years. Startup ZeroAvia has been running test flights of small planes partially powered with hydrogen fuel cells. Airbus has also started up a program to test out hydrogen combustion engines.
And Universal Hydrogen is joining the race this week. The company has a test flight planned for its Dash 8-300, a regional aircraft with over 40 seats.
The major goal is to test out the propulsion system, which will use hydrogen fuel cells that turn hydrogen and oxygen into water vapor, generating electricity to power the plane.
The aircraft will fly with hydrogen fuel cells powering one side while a traditional jet engine runs on the other. It’s a standard practice for testing out new systems in flight, says Universal Hydrogen CEO and cofounder Paul Eremenko.
Even if the test flight is successful, there’s a long road ahead before cargo or passengers will climb aboard a hydrogen-powered plane. That’s because there’s a lot of infrastructure around airplanes, and a broad switch to hydrogen-powered flight may require rethinking a lot of it.
Take fueling, for example. Commercial airports today have an established network to fuel up planes. Jet fuel is carried in, usually on trucks or in pipelines to a central fueling system. Trucks can then pick it up and bring it to a plane as it sits at a gate.
That whole system might not work so well for hydrogen, Eremenko says. Pipelines carrying hydrogen are prone to leak, and keeping hydrogen in a liquid form requires cooling it down to cryogenic temperatures, which often means there’s a lot of loss when moving it from one container to another.
The solution, as Eremenko sees it, looks a lot like one of my prized possessions: a Nespresso coffee maker. Universal Hydrogen plans to build and use pods filled with hydrogen fuel that can be loaded and unloaded from its airplanes, preventing the need to transfer hydrogen between different containers.
The test flight this week won’t use those pods, since the focus is making sure the plane’s propulsion system works as intended. The Dash 8-300 that will be flying will be powered using hydrogen tanks filled up before flight, but future test flights will use the capsule system to test out how that works in the air, Eremenko says.
In the longer term, Universal Hydrogen wants to build a solution for all the hydrogen planes he hopes will be taking off in the years to come.
(As a side note, in order to fit these fuel capsules onboard, planes might need to get a little longer, Eremenko says. Others say planes might change shape completely to fly using hydrogen.)