April 25, 2023

SESAM project on the home straight

Video: DLR project SESAM – producing high-purity nitrogen with solar energy (in German)
Is it possible to produce pure nitrogen for agriculture by combining solar heat and air? Absolutely! The current state of the art is to produce nitrogen using cryogenic air separation. However, this releases large amounts of CO₂. An alternative process is thermochemical air separation, which works CO₂-free by using solar heat. In the SESAM project, the DLR Institute of Future Fuels has coupled thermochemical air separation with pressure swing adsorption (PSA) and installed it in a pilot plant. In a two-stage process, the PSA plant produces low-purity nitrogen. Subsequently, most of the residual oxygen is removed in the thermochemical cycle. The solar-generated nitrogen can then be used to produce ammonia-based agricultural fertilisers.

Can I produce nitrogen by combining solar heat and air? Yes, you can!

We have successfully demonstrated the production of high purity nitrogen by combining a pressure swing adsorption and a solar thermochemical cycle.

After just over three years, the SESAM project is coming to an end. The aim of the project was to explore solar fertiliser, starting from the production of nitrogen.

It was an inspiring journey until the first plant of this kind was installed and the first nitrogen was produced. We look forward to continuing, exploring new challenges and testing new materials for the process.

Many thanks to all the team members who made this project so successful!

For more detailed information on the project, please see our project description. To coincide with the end of the project, our new video explaining the air separation process has also been completed.


Dr. rer. nat. Martin Roeb

Head of Department
German Aerospace Center (DLR)
Institute of Future Fuels
Solar chemical process development
Linder Höher, 51147 Köln-Porz

Christian Siegel

Communication Officer
German Aerospace Center (DLR)
Institute of Future Fuels
Im Langenbroich 13, 52428 Jülich
Tel: +49 (0) 2461 93730-328