Hydrogen-powered flight is closer to takeoff than ever

Universal Hydrogen propellor plane taking off from runway

Companies like Universal Hydrogen are retrofitting planes with hydrogen fuel cells.

Despite only recently taking to the skies, hydrogen-powered planes are already assuaging some skeptics about their role within a more sustainable airline industry. And while current prototypes won’t be making transoceanic flights anytime soon, their proofs-of-concept could guide better, more efficient, and larger craft in the years to come.

As Canary Media highlighted on August 2, two California-based startups’ have recently run multiple successful test flights for their experimental hydrogen gas fuel cell propeller planes. Both prototypes involve retrofitting existing turboprops to accommodate hydrogen fuel technology, albeit in slightly different ways to achieve different goals.

Universal Hydrogen’s 40-passenger Dash 8 prototype, for example, pairs an original jet fuel engine alongside a 1.2 megawatt fuel cell and 800-kilowatt electric motor. According to the company’s CTO Mark Cousin, the Dash 8 has successfully flown a total of nine times as high as 10,000 feet while at speeds upwards of 170 knots (195 mph). Meanwhile, ZeroAvia’s modified 19-seat Dornier 228 has flown 10 times at 5,000 feet while traveling at 150 knots without any issues. The company’s twin-engine turboprop includes one standard fuel setup, as well as a 600 kilowatt combination of hydrogen fuel cells and batteries.

[Related: This plane powered by hydrogen has made an electrifying first flight.]

Air travel has steadily rebounded following countries’ easing of COVID-19 lockdown precautions. While the numbers still aren’t pre-pandemic levels, they are expected to surpass them by 2025, according to the International Energy Agency (IEA). All those additional planes in the sky come with carbon emissions—roughly 800 metric tonnes of it, as of last year. In order to ensure a sustainable future, the IEA estimates that nations need to keep those CO2 levels below 1000 metric tonnes through the decade’s end. Unfortunately, the organization currently deems the airline industry “not on track” to achieving the goal.

For years, industry experts largely agreed that hydrogen fuel airplanes simply weren’t economically or logistically viable, given issues such as hydrogen canisters’ space requirements and their overall power outputs. Over time, however, both Universal Hydrogen and ZeroAvia intend to transition to liquid hydrogen, which packs more of a punch while also taking up less canister space.

[Related: Watch this sleek electric plane ace its high-speed ground test.]

Given the current technological landscape, flights that can completely run on hydrogen will still likely be restricted to shorter distance journeys, but that could still put a major dent in airline emissions. According to a new report from the International Council on Clean Transportation, even a retrofitted fuel-cell plane could generate one-third less CO2 over its entire lifetime compared to even “e-kerosene,” i.e. fuel made from water, carbon dioxide, and electricity.

“The question of how to create sustainable air travel has plagued the green movement for decades,” Dale Vince, an environmental entrepreneur planning to utilize ZeroAvia’s engine for passenger flights between England and Scotland, told the BBC in July. “The desire to travel is deeply etched into the human spirit, and flights free of C02 emissions, powered by renewable energy will allow us to explore our incredible world without harming it for the first time.”