News Treehugger Voices Hydrogen-Fueled Planes Could Meet One-Third of Air Travel Demands by 2050 It could essentially freeze passenger aviation emissions at 2035 levels. By Sami Grover Sami Grover Twitter Writer University of Hull University of Copenhagen Sami Grover is a writer and self-described “environmental do-gooder,” now advising community organizations. Learn about our editorial process Published February 4, 2022 01:03PM EST Fact checked by Katherine Martinko Fact checked by Katherine Martinko Twitter University of Toronto Katherine Martinko is an expert in sustainable living. She holds a degree in English Literature and History from the University of Toronto. Learn about our fact checking process ICCT Share Twitter Pinterest Email News Environment Business & Policy Science Animals Home & Design Current Events Treehugger Voices News Archive As an Englishman living in the U.S., I was pleased to see Google Flights start to list relative emissions next to every single itinerary. After all, while there is much power in refusing to fly altogether, it’s not unreasonable to assume that many of us will continue to fly—and a shift to lower emissions routes could help heap pressure on airlines to finally start tackling their operational footprint. (Research by the International Council on Clean Transportation has found emissions can vary as much as 80% on different routes between the same two airports.) Yet it’s important not to confuse the addition of consumer choice with a comprehensive or even far-reaching solution. After all, it will first require a significant percentage of travelers to act on relative emissions—as opposed to price and/or convenience. And second, they/we will still be choosing between two different high emissions options. Nevertheless, I am still going to visit my mum. As such, I am constantly looking for updates and glimmers of hope on the possibility of truly clean aviation options. So far, much of the discussion has focused on either electric flights, which look promising for short-haul flights only, or sustainable aviation fuels (SAFs), which are going to be extremely difficult to scale without massive knock-on environmental impacts from sourcing of feedstocks. That’s why I was intrigued and somewhat excited when Dan Rutherford of the International Council on Clean Transportation (ICCT) emailed me about a new report exploring the potential for hydrogen-fueled aircraft to meet demand. According to that report, which Rutherford co-authored with Jayant Mukhopadhaya, an aggressive rollout of narrow-bodied, hydrogen-powered turboprop planes could see them meet as much as one-third of demand by 2050, a move which would essentially freeze passenger aviation emissions at 2035 levels: “Under the most optimistic fuel and fleet turnover assumptions, evolutionary LH2-powered aircraft could cap, but not absolutely reduce, aviation CO2 compared to 2035 levels. This would require all replaceable missions in 2050 to be serviced by LH2-powered aircraft using green hydrogen and would result in mitigation of 628 Mt-CO2e in 2050, representing 31% of passenger aviation’s CO2e emissions.” That said, an aggressive rollout is very far from certain. In fact, the aviation industry has made extremely bold promises on emissions before—few of which have come even close to reality. So we might be wise to assume a more realistic adoption rate. Even here, Mukhopadhaya and Rutherford’s work still suggests the technology could make a significant contribution to minimizing emissions growth: “Internal modeling suggests that a 20% to 40% adoption rate is realistically achievable and would mitigate 126 to 251 Mt-CO2e in 2050, representing 6% to 12% of passenger aviation’s CO2e emissions.” Of course, anyone who has been paying attention to the climate crisis knows that "minimizing emissions growth" is a far cry from the kinds of aggressive cuts that we really need to be pursuing right now. So just as Rutherford told us in an interview last year, technological innovation isn’t going to replace the need—and shouldn’t be seen as an alternative to—ambitious efforts at demand reduction and replacing air travel with alternatives where possible. The release accompanying the report says as much: “Other technologies, including more fuel-efficient aircraft and sustainable aviation fuels, along with measures to moderate traffic growth will be needed to meet airlines’ aggressive climate goals of net-zero emissions by 2050.” So no, I’m not exactly breathing a sigh of relief or planning unlimited air travel just yet. Indeed, I’m unlikely to see truly zero-carbon air travel become the norm until the very end of my lifetime at best. Yet given the joy travel brings—and the difficulty of imagining a world where flying is truly off the table—I am pleased to see there’s potential for moving in the right direction. As for whether I’ll ever make it home on one of these planes, here’s what Rutherford told me via email: “It won’t get you over the pond in this configuration without a stop in say Greenland.” Sigh. But maybe it can offset enough demand for SAFs that I can fuel my flights by other means… Should We Fly Less or Fly More Efficiently?