This aviation emissions contribute to greenhouse gas buildup, worsening global warming. Several aviation teams are pursuing solutions to achieve a zero-emission fleet. The debate about the fuel of the future leans toward liquid hydrogen. A new project seeks to create a groundbreaking aircraft that runs on electricity and hydrogen.
Unlike traditional airplanes powered by fossil fuels, hydrogen aircraft offer a cleaner and more sustainable option. They operate with minimal noise, emitting only water vapor and avoiding greenhouse gas emissions.
The concept is to use renewable energy to generate liquid hydrogen, which in turn powers electricity and electric motors for aircraft. Researcher Xiaoze Pei from the University of Bath in the United Kingdom will start a 1.6 million euro project aimed at developing a hydrogen-powered, zero-emission electric airplane.
The project seeks to answer key questions about hydrogen-powered aviation, including energy efficiency, safety, reliability, and the performance of onboard power distribution networks.
Xiaoze Pei’s pioneering work in applied superconductors and cryogenic power electronics, in collaboration with Airbus UpNext and IXYS UK Westcode Ltd, is advancing the next generation of cryogenic and superconducting propulsion systems.
ZeroAvia has highlighted an aircraft powered by hydrogen and electricity, with a focus on clean propulsion.
One of the crucial breakthroughs is a highly efficient direct current distribution network using superconductors, which could make the overall power system lighter than current alternating current configurations.
The only viable solution
Xiaoze Pei is not alone in pursuing hydrogen-powered electric flight. English company ZeroAvia is developing hydrogen-powered commercial aircraft capable of carrying up to 19 passengers on regional routes.
ZeroAvia, which achieved its first flight in September 2020, is aiming to scale up to larger passenger capacities and to enable carbon-free long-haul flights by 2030. The company also projects significant cost reductions, with the goal of lowering flight costs by about half compared with today’s aircraft by 2024.
ZeroAvia asserts that hydrogen-electric propulsion can deliver energy density orders of magnitude higher than lithium-ion batteries, coupled with favorable cycle costs and advantages over other decarbonization options.
Airbus is also taking off
Another major player is Airbus, which is developing a hydrogen-powered passenger aircraft under the ZEROe program.
This hybrid aircraft family envisions three variants: a short-range regional configuration with about 100 seats, a medium-range variant for roughly 200 passengers, and a long-range version for up to 200 passengers, capable of flying up to about 3,700 kilometers. Airbus aims to introduce the world’s first hydrogen-powered commercial airplanes in the 2030s.
ZEROe aircraft rely on hydrogen combustion through modified gas turbine engines. Liquid hydrogen serves as the fuel for combustion with oxygen.
Hydrogen fuel cells can generate electrical power that complements gas turbines, resulting in a high-efficiency hybrid electric drive system. Airbus notes that these technologies work together to add benefits across the board.
Adapting airports
Projects are also underway with companies like Boeing, Rolls-Royce, and Honeywell. They focus on hydrogen production, the integration of electric propulsion into aircraft, and the manufacture of critical hydrogen-powered components.
Hydrogen is the most abundant element in the universe, so supply is not the main issue. Production can be achieved without emitting greenhouse gases, especially when driven by renewable energy sources through water electrolysis.
However, several challenges remain for hydrogen-powered aviation. A major hurdle is storage and transportation because hydrogen requires more space and high-pressure containment. Airports must support a reliable hydrogen supply, and large-scale production and distribution systems are needed to power these aircraft.
A study published in 2016 in Science suggested that liquid hydrogen will require major airport adaptations and new on-site fuel production infrastructures, along with substantial logistics investments.
Among the advantages cited for liquid hydrogen use in airplanes are cleaner engines compared with conventional jet fuel and potentially longer engine life with reduced maintenance costs.
For more information on hydrogen-powered aircraft, refer to the Science Direct study on hydrogen propulsion.
Notes from the environmental sector can be found in public repositories, including academic summaries and industry reports.