May 10, 2024

Opportunities on the Path to More Climate-Compatible Aviation

TAIEX Workshop
Potential of sustainable fuels and hydrogen in air transport
Improving the climate compatibility of air transport is an urgent concern, and current research is shedding light on promising ways to achieve this. Two recent papers from the DLR Institute of Air Transport present findings from an economic perspective on sustainable fuels and hydrogen as potential solutions for more climate-compatible flying.


  • Sustainable Aviation Fuels (SAF) offer a significant opportunity for reducing CO2 emissions in aviation in the short to medium term
  • A simulation suggests that global demand for hydrogen in aviation could reach 17 million tonnes by 2050, potentially leading to a 9% reduction in CO2 emissions*
  • Both research papers stem from projects addressing the economic evaluation of alternative energy sources in aviation and the sustainable transformation of the transportation system

Sustainable Aviation Fuels as Short- to Medium-Term Solutions

The use of Sustainable Aviation Fuels (SAF) is increasingly gaining attention as a promising means to make aviation more climate-friendly. A recently published paper titled "Pathway to net zero: Reviewing sustainable aviation fuels, environmental impacts and pricing" delves deeper into the potentials of SAF. Authors Matthias Braun, Wolfgang Grimme, and Katrin Oesingmann from the Institute of Air Transport at the German Aerospace Center discuss the importance of SAF in reducing CO2 emissions in aviation. However, they also point out that despite growing interest, challenges remain in building the necessary infrastructures and supply chains. Currently, in Europe, only about one percent of the fuels consumed by airlines are blended with sustainable alternatives. The paper examines various production pathways for SAF, their environmental benefits, and estimated fuel prices. It also considers the role of regulatory measures in different regional markets to promote the acceptance and adoption of SAF.

Hydrogen as a Long-Term Perspective

In the long term, hydrogen could play a crucial role in decarbonising aviation. Another paper titled "Hydrogen in aviation: A simulation of demand, price dynamics, and CO2 emission reduction potentials" offers new insights into the potential of hydrogen as an alternative fuel. Authors Katrin Oesingmann, Wolfgang Grimme, and Janina Scheelhaase from the Institute of Air Transport at the German Aerospace Center develop a model to forecast potential demand for liquid hydrogen in aviation by 2050.

The simulation suggests that global demand could reach up to 17 million tonnes, potentially leading to a significant 9% reduction in CO2 emissions. *However, the realisation of this potential depends on the competitiveness of hydrogen costs compared to other decarbonisation options. The study indicates that hydrogen costs must be competitive to meet the entire demand in aviation. This is likely to require a reduction in production costs, potentially resulting in a price of around 70 EUR/MWh by 2050.

*According to assumptions regarding market readiness, replacement rates, and ranges, the DLR study "Market uptake and impact of key green aviation technologies" , published in 2023 in the context of the Clean Aviation Partnership’s Strategic Research and Innovation Agenda (SRIA), suggests potential savings of up to 23% in CO2 emissions. Preconditions would include earlier market entry (2035 instead of 2040) and accelerated retirement of conventional aircraft.

Research Contributions for More Climate-Compatible Aviation

Both papers stem from research projects focusing on the development and evaluation of technologies to improve the climate compatibility of aviation. The German Aerospace Center's (DLR) ÖKONVER-2 project focuses on the economic evaluation of innovative technologies and measures in the transportation sector, while the Vmo4Orte project develops solutions for climate-friendly and sustainable mobility. The insights from the papers also contribute to the DLR aviation project EXACT.

In addition to other aspects, the Institute of Air Transport also investigates innovative operational procedures and technological measures that offer further potential for reducing the environmental impact of aviation.


Dr. Janina Scheelhaase

Acting Head of Department
DLR - Institute of Air Transport
Air Transport Economics
Linder Höhe, 51147 Cologne
Tel: +49 2203601 2187

Franziska Bietke

Communication Manager
DLR - Institute of Air Transport
Blohmstraße 20, 21079 Hamburg
Tel: +49 40 2489641-209