In Freiberg, an innovative hydrogen storage power plant is being developed. The project combines electrolysis and iron nugget technology for efficient energy storage. Ambartec AG and TU Bergakademie Freiberg aim to commercialize the technology, which has previously only been used in demonstration facilities. The Free State of Saxony supports the development with nearly 4 million euros.
According to the operators, this is the first hydrogen storage power plant in Europe based on iron nuggets. The project partners will receive funding of 3.85 million euros from the "R&D Joint Project Funding 2021-2027" program of the Free State of Saxony and the European Union. This was announced by the Dresden-based startup Ambartec on Monday (January 27).
The total project volume amounts to approximately 6 million euros, with the company founded in 2020 contributing 2 million euros from its own funds. The implementation will take place on the site of the Saxonia Location Development and Management Company in Freiberg. Ambartec has already conducted successful tests with prototypes there since the end of 2022.
H2 Storage Using Chemical Process
The technology aims to address two central challenges of hydrogen storage: cost efficiency and safety. Established methods like compressed gas storage or liquefaction are either energy-intensive or require complex infrastructures. Ambartec's solution is based on a two-stage chemical process using iron: Initially, hydrogen is stored in iron nuggets after electrolysis, reacting with contained iron oxide. Water vapor is produced as a by-product, which can be directly reused in the electrolysis plant.
To release the stored hydrogen at the point of use, water vapor is directed into the storage unit. This water vapor reacts with the iron, releasing the stored hydrogen. Practical tests in the demonstration facility in Freiberg showed, according to Ambartec, that this cycle works very efficiently. In combination with high-temperature electrolysis (SOEC), it enables efficiencies of over 80 percent.
The technology is implemented in a 20-foot container with a storage capacity for 800 kg of hydrogen. This corresponds to energy storage of at least 72 hours – a figure based on the draft of the power plant safety law. As Uwe Pahl, technical board member of Ambartec, emphasized, the containers can be transported by truck, train, or ship. This enables planned flexible hydrogen supply even outside the planned hydrogen core network.
Scientists Accompany Project Implementation
The Institute for Energy Process Engineering and Chemical Engineering at TU Bergakademie Freiberg will scientifically accompany the pilot operation. Prof. Martin Gräbner, Institute Director for Energy Process Engineering, described the project as an important contribution to the strategy of "electrification of carbon cycle and hydrogen technologies":
"In addition to the scientific monitoring of the pilot operation, the focus is primarily on modeling the ongoing processes. We are pleased to contribute to this forward-looking technology within the framework of this project."
Saxony's Minister of Economic Affairs, Dirk Panter (SPD), emphasized the strategic importance of the project for the competitiveness of the state's economy and its transformation towards renewable energies.
