By 2035, the world’s first zero-emission commercial aircraft could take to the skies. To bring this vision to reality, Airbus is exploring game-changing concept aircraft – known as ZEROe – powered by hydrogen, a disruptive zero-emission technology with the potential to reduce aircraft emissions by up to 50%.
Airbus has revealed three concepts for the world’s first zero-emission commercial aircraft which could enter service by 2035. These concepts each represent a different approach to achieving zero-emission flight, exploring various technology pathways and aerodynamic configurations in order to support the Company’s ambition of leading the way in the decarbonisation of the entire aviation industry.
All of these concepts rely on hydrogen as a primary power source – an option which Airbus believes holds exceptional promise as a clean aviation fuel and is likely to be a solution for aerospace and many other industries to meet their climate-neutral targets.
“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. 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,” said Guillaume Faury, Airbus CEO. “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.”
At first glance, the three recently unveiled Airbus “concept” aircraft offer little more than a sense of déja vu. One looks remarkably similar to a classic commercial aircraft – except with longer, more flexible wings. Another resembles a turboprop-powered airliner with its arrangement of eight-bladed propellers. And the third is a “blended-wing body,” a revolutionary design that has seen some traction among engineers over the last year.
But upon closer inspection, the trio features one game-changing difference compared to predecessors: hydrogen propulsion.
“As recently as five years ago, hydrogen propulsion wasn’t even on our radar as a viable emission-reduction technology pathway,” explains Glenn Llewellyn, Airbus Vice President, Zero-Emission Aircraft. “But convincing data from other transport industries quickly changed all that. Today, we’re excited by the incredible potential hydrogen offers aviation in terms of disruptive emissions reduction.”
That is indeed the objective. Airbus recently announced its ambition to develop the world’s first zero-emission commercial aircraft by 2035. This means only the most disruptive zero-emission technology to reduce the aviation industry’s climate impact will need to be rigorously tested and evaluated. And hydrogen certainly stands out from the pack: according to internal calculations, Airbus estimates hydrogen has the potential to reduce aviation’s CO2 emissions by up to 50%.
“These concepts will help us explore and mature the design and layout of the world’s first climate-neutral, zero-emission commercial aircraft, which we aim to put into service by 2035,” said Guillaume Faury. “The transition to hydrogen, as the primary power source for these concept planes, will require decisive action from the entire aviation ecosystem. Together with the support from government and industrial partners we can rise up to this challenge to scale-up renewable energy and hydrogen for the sustainable future of the aviation industry.”
In order to tackle these challenges, airports will require significant hydrogen transport and refueling infrastructure to meet the needs of day-to-day operations. Support from governments will be key to meet these ambitious objectives with increased funding for research & technology, digitalisation, and mechanisms that encourage the use of sustainable fuels and the renewal of aircraft fleets to allow airlines to retire older, less environmentally friendly aircraft earlier.
“Hydrogen has a different volumetric energy density than jet fuel, so we have to study other storage options and aircraft architectures than existing ones,” explains Jean-Brice Dumont, Airbus Executive Vice President, Engineering. “This means the visual appearance of our future zero-emission aircraft will change. These three configurations provide us with some exciting options for further exploration.”
In aircraft, there are two broad types of hydrogen propulsion: hydrogen combustion and hydrogen fuel cells. Airbus’ three zero-emission “concept” aircraft – known as ZEROe – are all hydrogen-hybrid aircraft. This means they are powered by modified gas turbine engines that burn liquid hydrogen as fuel. At the same time, they also use hydrogen fuel cells to create electrical power that complements the gas turbine, resulting in a highly efficient hybrid-electric propulsion system. However, each option has a slightly different approach to integrating the liquid hydrogen storage and distribution system. Airbus engineers have conceptualised integration solutions that carefully take into account the challenges and possibilities of each type of aircraft.
The three concepts for the world’s first zero-emission commercial aircraft
The “blended-wing body” design (up to 200 passengers) concept is the most interesting of the three. The game-changing “blended wing body” design could generate up to 20% fuel savings and significantly improve the passenger experience thanks to its exceptionally spacious cabin layout. The next generation of single-aisle aircraft has a lot to learn from MAVERIC, Airbus’ latest aircraft demonstrator.
This is the concept behind MAVERIC, an aircraft demonstrator unveiled at Singapore Air Show 2020. The innovative design—known as a “blended wing body”—is a complete departure from traditional aircraft architecture thanks to a wide cabin layout that completely breaks the mould of conventional single-aisle aircraft. In fact, the design is so radical, some engineers did not believe in its potential at first.
For Airbus, the demonstrator’s potential to deliver real environmental performance benefits is of significant interest: approximately 20% less fuel burn compared to current single-aisle models with the same engine. The spacious configuration also opens up the design space, enabling the possible integration of various other types of propulsion systems. In addition, noise is expected to be significantly reduced thanks to a “shielded” engine that is mounted above the central body.
And, if commercialised, a MAVERIC-inspired aircraft could significantly improve the passenger experience. A blended wing body design provides an exceptionally comfortable cabin layout, enabling passengers to benefit from additional legroom and larger aisles for more personal comfort.
The world’s first zero-emission commercial aircraft by 2035
If hydrogen technology development progresses at the expected rate, Airbus’ highly anticipated zero-emission commercial aircraft is expected to roll off the assembly line for entry-into-service by 2035.
To meet this ambitious 2035 target, Airbus will need to launch the ZEROe aircraft programme by 2025. This time frame gives Airbus engineers approximately five years to mature all the required hydrogen technologies. Over the coming months, several hydrogen demonstrator programmes – which will test hydrogen fuel cell and hydrogen combustion technologies respectively – are estimated to be formally launched. A full-scale aircraft prototype is estimated to arrive by the late 2020s.
Hydrogen is the most abundant element on earth. As one of two elements that forms water, it occurs in vast quantities in oceans, rivers, lakes and the atmosphere.
Hydrogen is incredibly versatile and has a variety of applications, including as feedstock and as fertilizer. In recent years, hydrogen has been used by the transport sector to power cars, buses, trains, bicycles, and motorcycles in various forms. In fact, NASA began using liquid hydrogen as rocket fuel in the 1950s, and was one of the first to use hydrogen fuel cells to power the electrical systems on spacecraft.
In the aviation sector, engineers have identified three hydrogen technologies that could play a role in fuelling future aircraft:
- Hydrogen combustion in modified gas-turbine engines: This technology works in the same way as conventional internal combustion, which generates motive power (thrust) by burning gas, kerosene oil or other fuel. In this case, hydrogen (liquid or gas) simply replaces its fossil-fuel counterpart.
- Hydrogen fuel cells: This technology is a device that converts energy stored in molecules into electrical energy. During oxidation, hydrogen atoms react with oxygen atoms to form water, a process during which electrons are released and flow through an external circuit as an electric current to potentially power an electric or hybrid-electric propulsion system.
- Synthetic fuels: This net-zero carbon fuel is created when hydrogen produced via renewable electricity is combined with carbon dioxide. This fuel can already be added to fossil fuels and used in conventional jet engines.
Is hydrogen a “zero-emission” technology?
Hydrogen is a flammable, gaseous substance that emits no CO2 if generated from renewable energy through electrolysis. In this case, water and heat are the only by-products, a process through which no emissions other than water vapour are produced.
Hydrogen is also an energy carrier that can stabilise electricity networks provisioned by renewable or carbon-free sources, such as wind turbines and solar panels. Because renewable hydrogen draws on renewable energy sources, it is considered as “cleaner” and more sustainable than comparable energy-storage systems.
It is for this key reason that aeronautics engineers—including those at Airbus—are taking a closer look at hydrogen as a potential technology pathway for zero-emission aircraft. In the years to come, research into hydrogen is expected to ramp up exponentially as the aviation industry ecosystem assesses hydrogen’s technical and economic viability.
Photo credits: Airbus Industries