Hydrogen-Powered Aircraft: Hydrogen–electric hybrid propulsion for aviation

Abstract

The ever-increasing demand for passenger air travel means unprecedented aircraft market growth in the coming decades. However, large airline fleets lead to serious environmental concerns. A clear goal was set during the 2021 United Nations Climate Change Conference (COP26): securing global net-zero emissions by midcentury while keeping 1.5 °C of temperature rise within reach. Hydrogen (H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) propulsion technology provides one of the most promising opportunities to meet this target and decarbonize global aviation. Thus, this article reviews and collates state-of-the-art research related to H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> –electric hybrid aircraft. After introducing the potential benefits of H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> propulsion, fuel cell (FC) auxiliary power in airplanes and H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> FC-powered aircraft are discussed. Finally, challenges/recommendations for future research as well as an outlook on H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -powered aircraft are presented.