Reduction of investment and operating costs of electrolysers by using alkaline membranes as well as innovative design concepts and operating strategies
To fully utilize the potential of reducing the cost of electrolysers, the project ALELY (Alkaline Electrolysis) sets its focus on the reduction respectively substitution of raw and functional materials and the lowering of cell overvoltage for the purpose of decreasing the specifically required electricity demand on hydrogen per volume unit. Furthermore, the project incorporates the development of dynamic operating strategies.
September 2021 until August 2024
Federal Ministry for Economic Affairs and Climate Action
Institute of Engineering Thermodynamics
Institute of Networked Energy Systems
Evonik Operations GmbH, Research, Development & Innovation
EWE GASSPEICHER GmbH
Persons responsible for the project ALELY at the Institute of Networked Energy Systems:
Juan Camilo Gómez Trillos
Electrolysers are a key element in the production of hydrogen from electrical energy. As for now, electrolysers with so-called proton exchange membranes are used for this purpose. The extremely acidic conditions require the use of correspondingly inert and therefore expensive materials.
In order to achieve a significant reduction in the investment costs of electrolysers, the use of an anion exchange membrane (AEM) represents a promising solution. This approach allows to combine the advantages of conventional proton exchange membrane electrolyser (PEMEL) with classical alkaline electrolyser (AEL). Advantageous characteristics of PEM electrolysers are high current and power densities, pressurized operation and dynamic load changes.
The operation within the alkaline milieu leads to a significant reduction of material costs, for example by the use of non-noble metal catalysts and the substitution of titanium as a material for bipolar plates.
The consortium of the project ALELY under the leadership of DLR consists of three companies and two research institutes. The topics of research cover the development of materials, the establishment and optimisation of production methods, characterisations on the material, stack and system level, the overall system optimisation and field test validations.
The activities on the part of DLR are performed by two institutes. The focus of the Institute of Technical Thermodynamics is primarily on structural characterization and degradation analysis as well as measuring the current density distribution in the improved electrolysis cell and stack designed by the project partners. The Institute of Networked Energy Systems is dedicated to develop and perform the system tests of the electrolyser and long-term testing. In addition, a techno-economic analysis will be carried out to compare anion exchange membrane electrolyser with a conventional alkaline electrolyser. This aims at identifying potential savings by feasible optimisation measures regarding the efficiency degree and the lifespan of the new concept.