A scalable system demonstrator for alkaline pressure electrolysis with an output of 1MWel has been engineered in Germany.
As of 2026, the system will continue to operate in the H2 GeNeSiS model region and feed hydrogen into the new pipeline along the Neckar River.
The development is part of the “Electrolysis Made in Baden-Württemberg” project, which was completed in 2023, the Baden-Württemberg Center for Solar Energy and Hydrogen Research (ZSW) and was made with the participation of 40 companies.
The pump specialist LEWA from Leonberg also contributed to the success of the project. An ecoflow diaphragm metering pump with Ex motor feeds the water required for hydrogen production into the process.
The aim of the Electrolysis Made in Baden-Württemberg project, which was funded by the Baden-Württemberg Ministry of Economic Affairs, was to develop a CE-certified, production-ready alkaline water electrolysis system with an output of 1MWel, which can be scaled for various industrial applications thanks to its modular design.
“Electrolysis systems in this performance class are particularly suitable as so-called H2 hubs for decentralized hydrogen production,” said Frank Baumgart, laboratory manager in the Regenerative Energy Sources and Processes (REG) department at ZSW and the main person responsible for the design and construction of the electrolysis demonstrator.
“These are used by filling stations or industrial processes that require hydrogen, for example.”
A total of 40 companies were involved in the realization of the “Made in Baden-Württemberg” system demonstrator. They contributed the individual process and electrical engineering components to the pilot project, as well as valuable know-how.
The project partners had the opportunity to gain experience in this special application area and to test their components in the actual application environment.
“The requirements for an electrolyzer are complex,” said Baumgart.
“On the one hand, high pressures and temperatures of up to 90 C are required to achieve the best possible overall efficiency.
“Secondly, the material resistance of all system parts must be ensured, since individual components come into contact with demineralized water, alkaline electrolyte or hydrogen or oxygen.”
With the pump that feeds the water required for hydrogen production into the process, the process engineering specialists from LEWA contributed a central component at the heart of the system.
The ecoflow diaphragm metering pump feeds in exactly the amount of process water that is consumed during electrolysis.
This requires the flow rate to be precisely adjusted to the actual consumption conditions in real time. Otherwise, the metering process would have a negative effect on the system’s closed control loops.
“Metering is therefore carried out using two-point control,” said LEWA area sales manager Björn Pfizenmayer.
“The unrivalled suction capacity of LEWA pumps ensures a continuous process.”
For this complex task, LEWA chose the ecoflow LDC1 M910S, which has a hydraulic output of 0.2 kW and was equipped with an Ex motor due to the hydrogen produced during the process.
The electrolysis system demonstrator Made in Baden-Württemberg with a CE marking has been in operation at ZSW since 2023. The 1MWel system is also a basic model and, thanks to its modular design, larger output classes up to the double-digit megawatt range can be scaled from it in the future.
The demonstrator itself will eventually feed hydrogen into the new pipeline along the Neckar River as of 2026, as part of the H2 GeNeSiS model region at the port of Stuttgart.
“From the individual components to the electrolysis stack and the system technology, the demonstrator serves as a showcase for the technology and regional value creation potential of Germany as a hydrogen location,” said Baumgart.