The ETH Initiative on the Decarbonization of Aviation is a call for establishing more research at ETH Zurich towards decarbonizing aviation, reducing its dependence on fossil fuels and thus its climate impact. Two master’s students, Simon Wahl and Oskar Jönsson, initiated the effort by submitting an ETH+ proposal to the ETH executive board in fall 2018, which was drafted in collaboration with seven professors. The board granted funding to develop the idea further and specifically delineate how and where ETH Zurich can contribute to decarbonizing aviation by 2050. SCCER Mobility is supporting the coordination of this work.

To this end, the team conducted desk-based research and expert interviews this year to find out what other academic institutions are already doing and what kind of challenges companies face. This resulted in a background report, which outlines the current state of research and activities in the area of decarbonizing aviation. From the 21 interviews with experts from ETH Zurich, governmental agencies, NGOs and industry in Switzerland, synthetic fuels crystallized as a topic of importance. Interviewed experts believe that renewable electricity that is converted to gaseous or liquid fuels is the most promising option. However, many challenges still need to be tackled including technological and economical scalability as well as impacts of non-CO₂ emissions. Along with improving efficiency at the aircraft and operation level, carbon offsetting was also viewed as central. Biofuels and electrification of both short- and long-haul flights were not identified as feasible options for environmental, economic and technological reasons, respectively. Besides these technology-based pathways, managing the demand for aviation was also pinpointed as an effective measure for reducing aviation-related emissions.

Number of interviewees with negative/positive perception of the respective measure.

Based on this report and as a further step, the Initiative on the Decarbonization of Aviation hosted a one-day workshop on 14 October with approximately 30 expert stakeholders. The researchers attending included ETH professors and post-docs from the Departments of Mechanical and Process Engineering (D-MAVT), Environmental Systems Science (D-USYS), Civil, Environmental and Geomatic Engineering (D-BAUG) and Humanities, Social and Political Sciences (D-GESS) as well as from University College London. Half of the participants represented different companies and organizations including Swiss International Airlines, Zurich Airport, RUAG, AEROSUISSE and SAFRAN. Representatives from ETH Sustainability and the ETH Mobility Platform also participated.

Some major points emerged from this workshop. Fuel and propulsion technologies, primarily synthetic renewable jet fuels, will be important. However, big uncertainties remain around how to make such technologies economically viable and which of the technologies will make the race in the end. Furthermore, holistic research is critically needed to interface these technologies with the corresponding infrastructure systems as well as address the economic, social and management issues that accompany their use. Participants recommended that ETH Zurich should enter this field by building on its current strengths in the development of alternative fuels and combustion systems and its expertise in assessing environmental impacts and socio-economic implications of new technologies. This could be implemented by forming a new professorship for sustainable aviation systems or establishing a cross-departmental and interdisciplinary research platform. Finally, this would ideally contribute to expanding the current teaching at ETH related to aviation systems with a significant focus on sustainability. Next steps are ongoing, so stay tuned.

Initiative on the Decarbonization of Aviation - background report

Simon Wahl (l) and Oskar Jönsson (r) are master’s students in Environmental Science at ETH Zurich. They have been involved in university politics since the beginning of their studies and are active in the Student Sustainability Commission. Oskar and Simon campaigned with other students to make ETH aware of its carbon footprint resulting from air travel and think it should do more research in making aviation carbon neutral.