Airbus sees hydrogen as the pathway toward its goal of bringing a zero-emissions commercial airliner to market in the next decade, a key executive said Tuesday.
But that executive, Glenn Llewellyn, v-p of zero-emissions technology for Airbus, agreed with other panelists during an FIA Connect 2020 webinar titled “Clean Flight – Path to Zero Emissions Aircraft” that hydrogen ranks among multiple approaches that will be necessary to reach their ultimate sustainability goals.
“We’ve been very clear recently that we have the ambition to bring a zero-emissions commercial airliner to market in the early 2030s, and one of the most promising technologies to allow us to do that is hydrogen,” Llewellyn said. “We believe we need to position the aviation industry to be powered by renewable energy, and hydrogen is a very good surrogate for allowing us to do that.”
Hydrogen can be produced by solar or wind, he said, adding that energy can be carried onboard through fuel cells to drive gas turbines or a hybrid-electric combination of the two. That would enable a significant reduction in aviation’s effect on climate change, Llewellyn said.
“We are talking about making some significant decisions in the 2024 to 2025 timeframes in terms of the technology choices we need to make,” he said, adding that the technology development needs to progress fairly quickly over the next four to five years.
Such progress will entail reaching beyond “aircraft borders” to the automotive and space sectors, both of which have experience with hydrogen energy use, he said. In addition, Airbus believes the airport community must also prepare for hydrogen-powered aircraft in the 2030s. This means bringing hydrogen on the airport to power ground vehicles leading up to that point, he said. “That’s going to require work already starting today,” not just for aircraft but preparing the roadmap. Airbus already has begun the initial work, as well as reaching out to energy companies to scale for hydrogen usage. “That infrastructure piece is as important as the aircraft development piece,” noted Llewellyn.
Hydrogen, however, is just one approach needed for the future mix of fuels. Aircraft already have received certification to carry up to 50 percent of sustainable aviation fuels (SAF), such as biofuel. “That’s a huge lever that today we are not adequately using,” Llewellyn said, primarily because of the need to lower the cost. But SAF stands as the most promising short-term option. “There is no technology limit. There is no technology boundary in us being able to do more there,” he said.
Longer-term, however, scientists know the current generation of biofuel will reach a scalability limit, he said, adding aviation will need more investment into power-to-liquid synthetic fuels, such as those using Fischer-Tropsch synthesis involving hydrogen and carbon molecules. “We believe that it is a highly scalable sustainable aviation fuel,” he said, and that such synthetic fuels would not compete against hydrogen. Currently, hydrogen looks promising for aircraft up to 200 passengers, but SAF or power-to-liquid fuels might prove to be better options for larger aircraft, he said.
Riona Armesmith, chief project engineer for hybrid-electric propulsion for Rolls-Royce, agreed that in the short term “we’ve absolutely demonstrated” that the industry can use SAF immediately. “Hydrogen needs a bit more work” for use in gas turbines, but it is something Rolls-Royce is examining, along with electric. “It would be an easy to thing to say it is an either-or. It’s not; It’s both,” Armesmith said, adding the industry needs to support such efforts to push them forward "rather than just waiting to see what happens.”
“Nobody’s under the illusion that there’s one technology that’s going to solve [sustainability challenges],” agreed Eamonn Beirne, head of emerging aviation technologies for the UK Department for Transport. SAF stands as the most immediate approach, but other means, including hydrogen, look as if they can help deliver on sustainability.
“There are huge opportunities,” said Russ Dunn, chief technology officer and head of strategy for GKN Aerospace. Dunn noted most aircraft developed today employ older technologies, but there that significant advances have occurred in recent years. SAF is possible but needs the right economic conditions, Dunn added. However, “there are huge advances that you can make beyond that," he said. "SAF is an important ingredient...but one of the ingredients.”
Further opportunities exist in areas such as hydrogen and electric. “Not one of those individual ingredients will meet the requirements for zero-emissions aviation for net-zero 2050,” insisted Dunn, who added that the community must address new technologies, support SAF, and explore emerging technologies such as the use of hydrogen. “Yes, there are huge challenges to overcome but they are all are within our grasp,” he concluded.