BIGGIN HILL, London–As powertrain developers complete initial flight test programs with hydrogen-powered regional airplanes and orders begin to stack up from airlines eager to operate zero-carbon flights, attention is beginning to be paid to the infrastructure required to bring these concepts into service.
During a panel discussion held at the Air Charter Expo (ACE) here Sept. 12, industry insiders described some of the issues currently being worked through by airports, airlines, airframers and their suppliers.
“Aside from the technical challenges—which are all surmountable, and we have a good pathway to tackling those—we need to make sure we have the infrastructure for fueling in place,” says Dominic Weeks, head of external affairs at UK-U.S. hydrogen powertrain developer ZeroAvia. “We have quite a large hydrogen infrastructure team. Businesses like ours are not just looking at the powertrain, they’re looking at how can we actually establish the refueling capacity at an airport.”
ZeroAvia’s first product, the ZA600, is being targeted at small regional turboprops. Other manufacturers are also initially looking at this segment. Andy Smith is the head of sustainability strategy for Scottish operator Loganair, which he describes as “quite a large small airline.” The firm’s routes include several connecting Scottish islands with each other and the mainland. Britten-Norman Islanders and De Havilland Canada Twin Otters, two of the types targeted for conversion by hydrogen powertrain OEMs, are in their current fleet. Smith says the availability of hydrogen is not shaping up to be a problem.
“We’ve been having conversations with hydrogen producers who are desperate to find offtake agreements and supply hydrogen,” he says. “We’ve not been able to make commitments at this point because we don’t have a certified aircraft. But we are making sure that will factor into their production planning capacity, because we certainly feel within the UK that hydrogen is going to be such a large industry stream that’s going to come on.”
“The good news from a hydrogen standpoint is when you look at the volumes that are required for the initial aircraft, they’re pretty small, so it’s not a huge infrastructure expenditure to put in the capacity to support those flights,” Weeks says. “Longer term, if you look to other markets—say, to the U.S. and to the EU—there are huge programs in place to make sure that there is a surfeit of hydrogen.”
There is, though, no need to wait for certified hydrogen-powered platforms to fly without emitting carbon. Pipistrel’s Velis Electro is the first battery-powered electric aircraft to receive type certification, and while it is aimed at the flight school market rather than airline customers, it still has its own infrastructure requirements, which the manufacturer is helping to meet today.
“We need the support of local airports, governments, authorities to start putting three-phase power into airfields so we can put our chargers in place,” says Steve McKenna, UK-based director of sales and marketing for Textron eAviation’s Pipistrel business unit. “In the UK we’ve got nearly 14 airfields with electric chargers through our partners NEBOAir and Aerovolt. But more is needed in the UK specifically to get ready for what’s coming. Larger [battery-powered] airplanes are going to be a much bigger challenge and a much bigger draw on the power network.”
While there will be a role for central governments in facilitating, stimulating or perhaps underwriting some infrastructure and technology development programs, the result must be a commercially viable product. This may be the zero-carbon aviation sector’s biggest challenge.
“If you throw enough money at a problem, you can get it to fly, but we need to be able to do this in a way that’s going to enable passengers to travel at a viable price point,” Smith says. “The challenge we see initially is finding the right level of government and private investment support to get this technology through certification as a really important milestone. But we see the first five years or so of operation in service as being critical to maturing the technology and bringing the cost down to the point where we’ve got a competitive, viable solution.”
And for short-haul small-aircraft operations, he suggests that future hydrogen platforms may help square the cost circle versus the other lower-carbon alternative—sustainable aviation fuels (SAF).
“Gaseous hydrogen ... can be produced quite cheaply, quite locally,” he says. “For small aircraft we’re talking relatively small quantities. It can be done on site. Once you get to liquefaction, which is inevitably going to be required for larger aircraft and significant range, then it needs to be produced centrally to get the economies of scale to produce it. We’re still assessing this, but what we are quite clear on is that using hydrogen directly is going to be, we believe, a more cost-effective solution than, for example, SAF in the longer term.”