Phillip J. Ansell
In pursuit of developing a sustainable aviation future, the application of liquid hydrogen as an energy carrier for aircraft has emerged as an appealing strategy to achieve future zero-emission goals. Liquid hydrogen is uniquely capable of meeting the aggressive power and energy requirements of aircraft systems, though utilizing it requires a substantial and extensive transition process throughout the entire industry and energy supply infrastructure. This work is intended to demonstrate the feasibility of developing a hydrogen aviation ecosystem by the year 2050, in the form of a visionary blueprint that includes forecasts in energy, operations, aircraft systems, and infrastructure. The projected 2050 scenario is informed by a meta-analysis of roadmaps and forecasts across a broad range of technical areas, where hydrogen is demonstrated to achieve technical feasibility, scalability, economic competitiveness, and deep environmental benefits for use in aviation. It is demonstrated that liquid hydrogen applications can meet the stringent safety requirements of aviation with abatement of currently recognized hazards. The increase in global hydrogen production across the coming decades is projected to reduce the life cycle emission impacts of aviation operations by over 80% by 2050, which is enabled by decarbonization of hydrogen production pathways and electrical grids anticipated across all global regions. The cost of liquid hydrogen for aircraft, including gaseous hydrogen production, liquefaction, transportation, and distribution, is projected to decrease to $3.37/kg by 2050 to become commensurate or lower cost than that projected for kerosene fuels on a per unit energy basis. With the continued increase in air traffic and global aircraft fleets, a sufficient volume of hydrogen produced and accessible by aviation is anticipated to meet the energy demands of hydrogen aircraft of 2050. Concept aircraft for future generations of regional jet, narrowbody, and widebody hydrogen aircraft are also provided, which are capable of providing extreme improvements in energy efficiency when compared to the incumbent fleet at the corresponding entry into service timeframe. A significant investment in capital is identified to establish the necessary infrastructure for liquid hydrogen use in aviation, though the vast majority of these costs are associated with off-site energy/fuel production and processing capabilities, which can be strategically co-developed with other transportation and energy industries. Based on all of these conclusions, developing a burgeoning liquid hydrogen aviation ecosystem by 2050 is entirely feasible, but it requires purposeful investment, pursuit, and alignment both within and outside of the aviation community. As such, when determining a pathway for a sustainable aviation future, the question is not whether it is possible. Rather, the question is whether we, as an aviation community, will decide to bring this future into being. • Establishes liquid hydrogen systems as part of the “sustainability age” of aviation. • Provides a scenario for hydrogen production across a mix of pathways for future decades. • Establishes cost feasibility and environmental benefits of future liquid hydrogen use in aviation. • Provides operational scenario for air traffic and aircraft fleet composition, demonstrating sufficient energy availability for hydrogen aircraft. • Forecasts overall cost and evolutionary development in on-site airport infrastructure for liquid hydrogen use.