Airbus has introduced three cutting-edge concepts for zero-emission commercial aircraft that could be landing at an airport near you as early as 2035.
They’re all part of Airbus’ broader strategy of becoming an industry leader in green aviation.
The ZEROe concept aircraft encompass three different approaches to emissions reductions, each with its own technological pathway. What they do have in common, though, is that they all rely on hydrogen as a fuel source. Let’s take a closer look at the designs of these cutting-edge passenger planes.
Short-Haul Turboprop Airplane
The first design is an aircraft with a 100-passenger capacity. It would be powered by a pair of modified gas turboprop engines, with six-bladed propellers, designed to burn liquid hydrogen. The airplane would have a flying range of about 1,000 nautical miles, making the plane well suited for regional feeder routes. The aircraft also uses electric batteries charged by the engines—which would be used to give the engines a power boost when necessary.
It looks very much like Airbus’ current fleet of turboprops with one noticeable difference: the lack of seats at the back of the aircraft. The aft seating rows would be removed to make room for the plane’s hydrogen tanks—resulting in less passenger space. Its closest existing comparable aircraft would be the Airbus A220-100.
Transcontinental Turbofan Aircraft
Second, Airbus has designed a turbofan plane capable of carrying 120 to 200 passengers over 2,000 nautical miles. This would make it a viable aircraft for transatlantic flights—and a potential successor to the Airbus A320. The turbofan would be powered by a modified turbine engine running on hydrogen.
As with the turboprop model, the liquid hydrogen fuel in this aircraft would be stored in tanks installed behind the rear pressure bulkhead, and distributed to the engines on the wings. It also features a chimney built into the vertical stabilizer to vent the hydrogen gas in case of a leak.
Blended-Wing Concept
The most unusual of the three ZEROe concept planes, this aircraft could carry up to 200 passengers and would have a range comparable to the turbofan model. It’s a radically different design—a giant flying wing. While the other two models look like conventional passenger jets, this aircraft has wings that merge with a fuselage that is much wider than in the other two concepts. Airbus has recently explored this configuration with its MAVERIC demonstrator.
This aerodynamically efficient design allows for much more room—and more configuration options—to accommodate more passengers as well as to store and distribute hydrogen fuel. Airbus hasn’t landed on a specific layout yet, and will explore the various possible layouts.
Why Hydrogen?
Hydrogen is appealing because it is the closest alternative fuel to matching the capabilities of fossil fuel engines. But tank design is crucial: hydrogen becomes liquid at -425 °F, so the tank will have to keep the element at that temperature from takeoff to landing.
Airbus sees a threefold use for hydrogen: it can be combusted directly through modified gas turbine engines; it can be converted to electric energy via fuel cells; and, when combined with CO2, it can be used to produce synthetic kerosene. The first two of those features are particularly important for the ZEROe aircraft. And if those technologies prove viable, it could even be possible to retrofit existing aircraft, such as the Airbus A320neo or the Boeing 737 MAX, with hydrogen-burning engines.
Airbus evidently sees hydrogen as the most viable way forward for zero-emissions passenger planes. The company has committed to hydrogen over other green power options because it is an “energy carrier that can be created using renewable energy, and carried on board an aircraft,” said Glenn Llewellyn, vice president, head of Zero Emission Aircraft at Airbus. He added that it is “an energy source which is required by many industries in order for us all to meet the Paris Agreement targets ... the scaling we’re going to see over the next few years, is going to significantly bring the cost down. This, on top, makes it very interesting for aviation.”
“I strongly believe that the use of hydrogen—both in synthetic fuels and as a primary power source for commercial aircraft—has the potential to significantly reduce aviation’s climate impact,” said Guillaume Faury, chief executive officer of Airbus.
One option missing from this plan: electric aircraft. Airbus has stated that it’s open to the idea of producing electric jets down the road, but those would likely use different designs than the ZEROe project and would be produced on a much smaller scale. “Battery technology is not moving at the pace we want, and this is where hydrogen comes in,” said Llewellyn. “It’s got several thousand times more energy per kilogram than what batteries could have today.”
Overhauling the Aviation Industry
As far out as these concept aircraft may seem, there’s a very real economic push behind them. The global aviation industry has committed to cutting carbon emissions to half their 2005 levels by 2050. Plane makers and airlines alike are facing mounting pressure from governments and customers to cut emissions—as seen in the recent “fly shaming” trend. And, of course, there’s the massive hit on commercial aviation due to the COVID-19 pandemic.
One airline—easyJet—has already come out publicly in support of the ZEROe concepts. The airline is already working in partnership with Airbus to research hybrid and electric aircraft and their related infrastructure requirements.
It’s not just the planes that are meant to turn the aviation industry on its ear—if these concepts are to become real, airports will need to invest a substantial amount in hydrogen transport, storage and refueling infrastructure.
A Market-Ready Aircraft by 2035
The ZEROe represents a hugely ambitious plan for Airbus, which intends to spend billions on the project. The company will pursue all three options at first, promising to show the initial results as early as the middle of 2021. The company is already working on a zero-emission demonstrator that would show how it’s possible to de-risk the refueling of a hydrogen-powered aircraft and safely store and distribute the hydrogen onboard.
The European aerospace giant said it would pick a final concept for development within five years.
“This is a historic moment for the commercial aviation sector as a whole and we intend to play a leading role in the most important transition this industry has ever seen,” said Faury. “The concepts we unveil today offer the world a glimpse of our ambition to drive a bold vision for the future of zero-emission flight.”
Read more about the promise of hydrogen-powered transportation at This Hydrogen-Powered Hypercar Boasts Space-Age Technology.