Criteria for the production of sustainable PtL for aviation

Derivation and definition of implementation criteria for the generation or procurement of sustainable electricity and CO2 as feedstock for PtL for aviation

© acinquantadue - Fotolia

When it comes to climate-friendly propulsion systems, there are hardly any alternatives to a renewable fuel for air traffic - unlike for road traffic with its possibility of extensive electrification. So-called e-fuels are at the forefront here: made from renewable electricity via electrolysis of water to hydrogen and synthesis with carbon dioxide (CO2) to liquid power-to-liquid (PtL) fuels. While EU legislation provides requirements for demonstrating the sustainability of biofuels, such requirements are so far lacking for PtL.

The objective of this study is to derive and define implementation criteria for the production and procurement of PtL for aviation. Because the technology is so new, care was taken in defining such criteria to ensure that, on the one hand, they meet a high standard of sustainability and are not limited to the level of minimum legal requirements. On the other hand, however, they should not "nip the technology in the bud" by imposing excessive requirements.

After a brief analysis of the need for PtL for aviation, the study describes the state of PtL production technology. Then criteria are developed based on global guard rails and sustainability goals, which are applied in the first step to the type and origin of CO2 as feedstock. The second step is to evaluate the greenhouse gas neutrality of the electricity used for production. With a view to the future stages, the directions for continuation at an adapted level of ambition are already being sketched out.