Hydrogen (H2) fuels are seen as alternative propulsion fuels to reduce aviation’s contribution to climate change as it does not produce carbon dioxide upon combustion. One major challenge for this transition is that hydrogen production routes often entail emissions that drastically reduce the environmental benefits of adopting the technology. Low-impact H2 production is associated with three processes; electrolysis powered by renewable energy, biological fermentation and biomass gasification. Impacts of the latter two can potentially be further reduced by carbon capture and storage. Several datasets to support life cycle assessments (LCAs) of mentioned H2 production routes exist, but are limited by different temporal and geographical scopes. Future changes in energy systems as well as technology developments will have a major effect on the long-term impacts of hydrogen production. Not considering these changes will distort decision-making based on prospective assessments. This study addresses this gap by harmonizing existing data for the three most prominent water electrolysis technologies and developing prospective H2 production life cycle inventory datasets for Europe. Only the production of hydrogen itself is considered, excluding liquefaction, storage and distribution to the aircraft refueling point. We consider the technological changes that are partially expected to lead to dramatic reductions in material intensities of the electrolysers. By harmonizing regionally specific background data, this work contributes to a clearer understanding of the conditions under which green H2 fuels can deliver substantial climate benefits as future aviation fuels. ... Read more