Sustainable Aviation: A techno-economic “Well-to-wake” evaluation of the aviation fuels LH2, LCH4 and Jet A-1

Abstract

This thesis presents a comprehensive techno-economic assessment of the implications if the aviation industry shifts from fossil-based kerosene towards the utilization of electricity-based fuels, with liquid hydrogen, liquid methane and renewable kerosene as the only fuel options. The entire pathway from the provision of renewable electricity, the fuel synthesis, logistics, changes at the airport infrastructure up to the utilization in different aircraft categories is considered. The pathway selected for analysis is based on the assumption that renewable electricity will be supplied at El Ouatia in Morocco, with the airports of Frankfurt and Munich in Germany acting as the fuel supply points for three different aircraft categories, each with a capacity of 100, 180 and 425 passengers, respectively. For these aircraft, up to 10 different destinations are considered, depending on the flight range of the evaluated aircraft. The different fuels are compared by determining the specific costs of air travel in €2020 per passenger per 100 km. It is shown that a shift towards electricity-based fuels significantly increases the costs of air travel compared to utilizing fossil kerosene with CO2 abatement costs exceeding 1300 €2020 per t CO₂. The results for an aircraft with a capacity of 180 passengers are 3.08, 4.57 and 5.11 €2020 per passenger per 100 km for liquid hydrogen, liquid methane and kerosene, respectively. It is shown that the supply of renewable electricity and the fuel synthesis itself dominate the overall costs. If the highest possible flight range for an aircraft with a capacity of 180 passengers is considered, they make up almost 80 % in the case of liquid hydrogen, 88 % in the case of liquid methane and more than 92 % in the case of kerosene. Thus, the investment of new airport infrastructure and the development of new aircraft have a less significant role. The results enable stakeholders from the aviation industry, policy makers and research institutes to focus on those aspects that will achieve the overarching “net zero” target of the aviation industry in the most economically way.