Green hydrogen has a hidden problem and scientists may have fixed it

There are also environmental concerns. Current PEM systems depend on so called forever chemicals (PFAS), substances the European Union plans to phase out because of their environmental and health risks. Addressing both the high costs and the chemical concerns is the goal of the EU funded SUPREME project. Over the next three years, researchers led by the University of Southern Denmark, working with Graz University of Technology (TU Graz) and other partners, will develop a PFAS-free electrolysis system that is more efficient and uses far smaller amounts of critical raw materials such as iridium. The aim is to make green hydrogen significantly more affordable and sustainable.

Making Green Hydrogen Cleaner and Cheaper

"Hydrogen is used as a raw material in very large quantities, and this will continue to increase in the future. These include the production of ammonia, methanol production and the steel industry," says Merit Bodner from the Institute of Chemical Engineering and Environmental Technology at TU Graz.

"If we succeed in avoiding the use of harmful substances in the production of green hydrogen and we can also bring it to a similar price level as fossil hydrogen in economic terms, we will have taken an important step towards the green transition. This also makes it more attractive for other applications, such as storing surplus energy from renewables."

Hydrogen already plays a central role in major industrial processes, and demand is expected to grow. Making its production cleaner and more competitive with fossil based hydrogen could accelerate its use not only in heavy industry, but also as a way to store excess renewable energy.

PFAS Free Materials and Advanced Membranes

TU Graz has a leading role in evaluating safer alternatives. Bodner's team is reviewing commercially available PFAS-free materials and comparing their performance with current industry standards. A key question is whether these more sustainable materials can match the durability and efficiency required for continuous industrial use.

Meanwhile, the Turkish Science and Technology Council TÜBITAK is focusing on membrane development. The group is working on a new generation of microporous PFAS-free membranes designed for use in future electrolysis systems.

Cutting and Recycling Iridium

Another major focus is reducing reliance on iridium, a costly platinum group metal used in PEM electrolysis. The University of Southern Denmark and the British metal and catalyst company Ceimig are exploring ways to cut iridium use by up to 75 per cent. They are also developing recycling methods that could recover around 90 per cent of the iridium still needed.

Additional partners are contributing specialized components. Fraunhofer ISE in Germany is manufacturing the membrane electrode units, while the Norwegian hydrogen company Element One Energy AS (EoneE) is designing a new rotating electrolyser intended to improve system performance.

The project is funded through CETPartnership, the Clean Energy Transition Partnership under the 2024 joint call for research proposals, and is co funded by the European Commission (GA N°101069750).