Energy-Based Assessment of Alternative Aviation Fuels for U.S. Domestic Transport Aircraft

The transition to alternative fuels offers a promising pathway to reduce aviation’s environmental footprint. This study investigates the impact of replacing conventional jet fuel with power-to-liquid hydrogen ([Formula: see text]), power-to-liquefied natural gas (Pt-LNG), power-to-liquefied petroleum gas (Pt-LPG), and power-to-sustainable aviation fuel (Pt-SAF) across five representative classes of transport aircraft operating within the U.S. domestic network. To isolate the effects of fuel utilization, the analysis focuses on direct operational emissions associated with fuel energy utilization. Mission simulations are performed utilizing RCAIDE, while emissions are estimated through a chemical reactor network model. The study captures trends for each aircraft-fuel combination and quantifies combustor- and mission-level emissions. Results highlight patterns in emissions and energy use across different classes of aircraft. [Formula: see text] operation produces no direct [Formula: see text] or CO emissions at the aircraft level but results in higher [Formula: see text] and [Formula: see text] emissions compared to Pt-SAF. Consequently, [Formula: see text] yields the lowest [Formula: see text] emissions per revenue passenger-kilometer among the fuels analyzed. Pt-LNG and Pt-LPG offer intermediate benefits, exhibiting progressively lower [Formula: see text] emissions relative to conventional jet fuel, alongside modest changes in other pollutants. These findings aim to offer insights into the challenges and opportunities associated with integrating alternative fuels into the existing U.S. domestic aviation network.