Report: Zero-Carbon Flights Could Enter Service by 2035

FlyZero, the U.K. study into zero-carbon emission commercial air travel, has published its vision for a new generation of aircraft powered by liquid hydrogen. Should companies be able to demonstrate hydrogen-powered aircraft by 2025, zero-carbon emission aircraft could enter service by 2035.

The report“Our Vision for Zero-Carbon Emission Air Travel” marks the conclusion of a 12-month study which set out to consider the feasibility of zero-carbon emission aircraft. The project concludes aviation can achieve net zero 2050 through the development of both sustainable aviation fuel (SAF) and green liquid hydrogen technologies.

Led by the Aerospace Technology Institute and backed by the U.K. Government, FlyZero has concluded that green liquid hydrogen is the optimum fuel for zero-carbon emission flight and could power a midsize aircraft with 280 passengers from London to San Francisco directly, or from London to Auckland with just one stop.

Jacobs was commissioned by FlyZero to provide specialist aviation and hydrogen expertise into the report, “Airports, Airlines and Airspace - Operations and Hydrogen Infrastructure”. The team collaborated with five U.K. airports to define the hydrogen infrastructure needed to support the operation of hydrogen powered aircraft. Three scenarios were investigated for the application of on-airport hydrogen infrastructure: (1) on site production of hydrogen through electrolysis and liquefaction, (2) off-site production of hydrogen gas transported to the airport via a pipeline where it is liquified and (3) off-site production of hydrogen which is transported to the airport by delivery trucks.

“Our Vision for Zero-Carbon Emission Air Travel” summarizes FlyZero’s findings in a range of key areas, including infrastructure and operations, which Jacobs contributed to:

• Infrastructure and operations – generating the quantity of hydrogen needed for aviation will require unprecedented renewable energy capacity. Transporting hydrogen to airports will require gaseous pipelines or liquid hydrogen tanker deliveries, while refueling aircraft will require larger diameter hoses and increased automation to ensure it can take place safely and efficiently alongside other aircraft.
• Technology – revolutionary technology breakthroughs are required in six areas to achieve zero-carbon emission flight: hydrogen fuel systems and tanks, hydrogen gas turbines, hydrogen fuel cells, electrical propulsion systems, aerodynamic structures and thermal management. The U.K. has expertise and capability today in these, but little in liquid hydrogen fuels.
• Carbon emissions – global cumulative carbon dioxide (CO₂) emissions from aviation could be reduced by 4 gigatons (Gt) by 2050 and 14 Gt by 2060. This requires 50% of the commercial fleet to be hydrogen-powered by 2050 and assumes midsize hydrogen-powered aircraft are operating by 2035, with hydrogen-powered narrowbody aircraft in service by 2037.
• Non-CO₂ emissions – burning hydrogen in a gas turbine emits no CO₂ or sulphur oxide (SO_x), but water emissions are over 2.5 times higher than for fossil fuel-powered aircraft. Particulate matter will largely be eliminated, and it is estimated that nitrogen oxide (NO_x) emissions will be reduced by 50 to 70%.
• Sustainability – developing a new generation of aircraft presents an opportunity to integrate sustainability into design and manufacture, and further improve the reuse of materials.
• Economics – from the mid-2030s liquid hydrogen will be cheaper than the most widely available sustainable aviation fuel (SAF), power-to-liquid.
• Market impact – the optimum route to decarbonizing aviation is through the accelerated introduction into service of a large commercial aircraft similar to FlyZero’s midsize concept which is capable of reaching anywhere in the world with just one stop. Less commercially risky than developing a narrowbody first, this midsize first approach would also allow infrastructure development to be focused on fewer, but larger international hub airports.
• Research – the U.K. requires a hydrogen research and development facility with open access for academia and a range of industries including aerospace, automotive, marine, space and energy.
• Climate science – research into the climate impact of emissions from hydrogen gas turbines, including through modelling and testing, is fundamental alongside the technology development.

“Realizing zero carbon flight is one of the most ambitious challenges we can contemplate. However, it could also be one of the biggest economic opportunities for the U.K.’s world-leading aerospace sector,” says U.K. Government Industry Minister Lee Rowley. “It’s great to see FlyZero’s final outputs following a year of intense research, successfully bringing U.K. industry together to think through how to reduce aviation’s impact on our Earth and sky while ensuring and celebrating the immense benefits of air travel and connecting the world.”

“Hydrogen-powered, zero-carbon flights are now a step closer as a result of FlyZero’s study,” states Jacobs Global Solutions Director Andrew Gibson. “If they are to become a reality, evolving airports to meet the needs of hydrogen-fueled planes must become a priority. While we can start with off-site hydrogen production transported by road, as demand grows more investment will be required at airports to ensure hydrogen fuel is available. This can be achieved through the integration of Net Zero strategies, airport masterplans, capital planning, and infrastructure.”

“FlyZero’s findings will help shape the future of global aviation with the U.K. at the forefront of sustainable flight through the design, manufacture and implementation of alternative fuels,” adds Gibson.

FlyZero Project Director Chris Gear explains: “Zero-carbon emission flight can be a reality. Tackling the challenge of our generation requires accelerated technology development and urgent investment in green energy together with regulatory and infrastructure changes.

“The next three years are crucial to develop the technologies, build our skills in liquid hydrogen and demonstrate capability here in the U.K., to enable our aerospace sector and supply chain to secure its role in a new era for aviation.

“Realizing hydrogen-powered flight by 2035 is a huge challenge but is essential if we are to maintain the social and economic benefits of air travel while protecting our planet and meeting our commitments to fight climate change,” he concludes.

The FlyZero project is publishing its detailed conclusions through a series of reports which explore the technology challenges, manufacturing demands, operational requirements, market opportunity and sustainability credentials of zero-carbon emission commercial aircraft. A series of more detailed and technical reports together with new supporting research from industry and academia are also available to organizations that meet the requirements of an access test.

Visit the public report, which includes Jacobs’ contributions.

For a full list of reports and information on how to access them, visitati.org.uk/flyzero-reports.