Airbus Zero Emission Plane - The Hydrogen Airbus

The airline industry accounted for roughly 2.4% of global carbon dioxide emissions in 2018, a figure that’s predicted to rise to closer to 5% by 2050. While long-distance travel has become such an ingrained part of many lives, for business and pleasure, it’s clear that the consequences of air travel on the environment are substantial. A solution, naturally, is a valuable thing, and in three different new aircraft plans, Airbus says they have one.

Late in 2020, the French company announced a new concept, the ZEROe, simultaneously revealing three different new aircraft designs, all under the same branding. The company says the new, Hydrogen-fuelled aircraft could be in service by 2035, and form part of their wider plan to “de-carbonize the aviation industry”. The three designs range from relatively recognizable planes with adaptations to their power source, to an unfamiliar reimagining of commercial aircraft. Shaped like a cross between a space shuttle and a paper aero plane, one concept is ambitious and unfamiliar compared to what we’d see on our runways today.

Concept

It has what Airbus are calling “a blended wing body configuration”; essentially a single solid triangular form, not unlike a smoothed out, commercial version of the angular stealth fighter. That design is certainly the most eye-catching, with its cabin wide and spacious, rather than cylindrical. The unusual layout has already been ‘proven’ as a shape concept through a 3-metre wingspan ‘MAVERIC’ remote control version, though minus the Hydrogen power. The other two look a little closer to conventional modern passenger aircraft. The turboprop model looks a lot like a modern jet, though making use of twin propellers on either wing for propulsion.

The turbofan is an even more familiar reimagining of a typical passenger aircraft, with huge jet-style propulsion engines mounted under either wing. The turbofan has a capacity of between 120 and 200 people, and a range of an impressive 2,000 nautical miles. The blended body aircraft would be similarly equipped in terms of distance and capacity, while the turboprop model is aimed at shorter flights of up to 1,000 nautical miles, carrying 100 or so passengers. The two more conventional designs, the turbofan and the turboprop, are, essentially, adaptations of existing layouts allowing aircraft to run on hydrogen, involving tanks located near the rear of the aircraft which supply to the engines. The fresh, modern-looking ‘blended wing’ design makes use of a concept Airbus is currently working on with Delft University in the Netherlands, that is thought to be up to 20% more efficient in cutting through the air, and offer more layout options than current aircraft. The improvement in efficiency exists even before the change in fuel source.

Image Credit : Airbus

How airbus intends to make these aircraft zero emission?

The obvious question, though, is how Airbus intends to make these aircraft zero emission? The answer lies in the use of Hydrogen. The Hydrogen fuel cell is actually quite well established, having been used as far back as the 1960s to power space rockets such as the Apollo 11 mission.

In practice, the cells work through the quick release of energy stored in the Hydrogen molecules, which generates electrical power, using an electrochemical process, essentially consuming just Hydrogen and Oxygen. Hydrogen enters a fuel cell on the anode side, where a catalyst splits it into negatively charged electrons and positively charged particles, while oxygen from the air around the plane enters the other, cathode, side of the cell. The positively charged particles are attracted to the cathode, and so pass through a porous membrane to the opposite side of the cell, where they combine with the oxygen to produce water as a byproduct. The electrons, flowing in the opposite direction, become an electric current, which provides power, in this case to the aircraft engine.

This kind of fuel system is good for the environment compared to conventional systems, first of all because of its relatively safe byproducts, but also because of how the Hydrogen is produced in the first place. As we all know, fossil fuels are not environmentally friendly on either end: they cost energy to remove from the ground, and create damaging byproducts when they’re burnt. Hydrogen, however, can be produced from seawater, using green energystrategies such as wind or wave energy to provide the power source for theinitial production process. This makes both ‘ends’ of the supply green compared to the product they’re replacing. The energy production also has no carbon dioxide byproducts. The cell also has a benefit over conventional batteries, in that it continues to supply energy for as long as a supply of Hydrogen can be pumped into the cell at the anode side, essentially meaning the limitation, like with conventional fuel, is how much Hydrogen can be carried on board (or, potentially, refueled in air!).

As Hydrogen is relatively light, this opens up plenty of possibilities, too, though its current storage tanks are heavier than conventional jet fuel, so the area will need work. While this type of fuel is currently expensive, Hydrogen’s price is expected to drop as it becomes more commonly used in green energy technologies, incentivizing its wider production. That’s not to say Hydrogen fuels are an absolute ideal. Water is a byproduct of the reactions used in this process to generate power, and while water is not a pollutant, at least as we’d understand the term, it is a greenhouse gas. That means it could still have an impact on global warming.

What about Pollutants?

Nitrogen Oxide, another minor byproduct, is also less than ideal, though the levels of Nitrogen oxide emissions are substantially lower than from conventional fuel. There is also some fear of how combustible Hydrogen is, though studies suggest it is safer than gasoline. Airbus is certainly exceptionally enthusiastic about the idea. "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," Guillaume Faury, Airbus' CEO, said. The French government seems to agree, having earmarked 10% of their 17 billion dollar Covid rescue package for the airline industry explicitly to be used on Hydrogen-powered aircraft. The company is not just talking about a few aircraft, either, but a redefining of the industry, with their three new concepts - and any later additions - at the heart of it. “We won’t be satisfied with simply putting a hydrogen-powered aircraft into the air: we’re targeting wide-scale adoption, and that starts with putting in place hydrogen infrastructure worldwide,”

Glenn Llewellyn, Vice President of Zero-Emission Aircraft, said. The plan is, essentially, for a total change in the way aircraft function from the mid-2030s onwards, as these aircraft come into commercial use. Along the way, Airbus have also emphasized the compatibility between hydrogen and other battery-powered sources, and may look to utilise both in some of their aircraft, as an effective compromise solution, not unlike a more environmentally leaning version of the modern-day hybrid car. For all Airbus’ efforts, though, there is still cynicism about the idea in the industry, in particular from those pointing to the development of sustainable fuels for use in current aircraft - something that is already in process, though on a small scale - as being a potentially more comfortable and straightforward route to a greener aviation industry. Alternative fuels are already capable of a 70% reduction in emissions. That said, 70% is nowhere near on a par with the Hydrogen based system Airbus propose, and two likely channels, we’d argue, are better than one. Should Airbus’ concept come to pass, it certainly beats the industry’s rather palty efforts to green itself so far: let’s face it, planting a few trees to offset your carbon footprint, as some airlines offer as part of a ticket cost, is better than nothing, but hardly a sustainable solution.

With a bit of luck, Airbus’ idea might offer commercial flight without the guilt, or the consequences for our planet’s future. Would zero emission options make a change to how often you fly? Would you be prepared to pay extra to use them?