Researchers from the Karlsruhe Institute of Technology (KIT) have achieved a significant technological milestone on the path toward sustainable aviation fuels. As part of the Kopernikus P2X project, they successfully demonstrated—for the first time at an industrially relevant scale—the coupling of highly efficient co-electrolysis with synthetic fuel production.
The process enables the climate-friendly production of fuels like kerosene from carbon dioxide, water, and renewable electricity. While the aviation sector remains difficult to electrify, sustainable kerosene produced via power-to-liquid (PtL) methods offers a promising alternative. “The aviation sector in particular will rely on sustainably produced kerosene for the time being,” explains Professor Roland Dittmeyer of KIT’s Institute for Micro Process Engineering (IMVT).
Co-electrolysis plays a central role in improving the efficiency of PtL processes. It electrochemically converts water vapor and CO₂ directly into syngas—a mixture of hydrogen and carbon monoxide—in a single step. This new approach, developed in collaboration with the industrial partner Sunfire, can recover up to 85 percent of the electrical energy used as chemical energy in the syngas. It also eliminates the need for a separate hydrogen production step, simplifying the overall process and enhancing efficiency.
At KIT’s Energy Lab, the syngas produced through co-electrolysis is compressed and then converted into long-chain hydrocarbons—known as syncrude—via Fischer-Tropsch synthesis in a microstructured reactor. These hydrocarbons serve as precursors for kerosene and other fuels. The reactor technology, developed at KIT, is already being commercialized by our member INERATEC.
In addition to demonstrating the technical feasibility of continuous coupled operation, researchers are exploring further energy optimization. For example, the heat released during synthesis could be reused as steam in the co-electrolysis step, further improving overall energy efficiency.
Having already achieved daily production of up to 100 liters of syncrude under real conditions, the facility is now being scaled up to 300 liters per day. In the final phase of the project, a larger Fischer-Tropsch plant is being constructed at the Höchst Industrial Park near Frankfurt, where daily output will reach the ton scale. The resulting fuel will be tested by aircraft engine manufacturers and research institutions to ensure compliance with aviation standards.
This development represents a major step forward in making synthetic aviation fuels a viable and scalable solution for climate-neutral flying.