PEM Electrolysis
Hydrogen a beacon of hope
Hydrogen is one of the great hopes for the energy transition and structural change in the Rhenish mining area. On the one hand, it can serve as a storage medium and thus compensate for fluctuating electricity production from renewable energies such as photovoltaics or wind power. On the other hand, it can replace raw materials in the chemical and steel industries that currently still come from fossil sources.
Hydrogen can be produced by electrolysis. Water is broken down into hydrogen and oxygen in electrolysers through a chemical reaction. Electricity is required to force this reaction. If the electricity for electrolysis comes entirely from renewable energies, the production of hydrogen is CO2-neutral. The result is so-called green hydrogen.
Increasing performance, but how? - PEM electrolysis
In its National Hydrogen Strategy, the German government assumes that hydrogen demand in Germany will increase from the current 55 TWh per year (with hydrogen being used as a raw material in the industrial sector) to between 90 and 110 TWh per year by 2030. Sustainable domestic hydrogen production is also essential for this. Production plants with a total capacity of 5 GW are to be built for this purpose by 2030. These plants can produce up to 14 TWh of green hydrogen per year from 20 TWh of electrical energy from renewable sources.
Although electrolysis capacity in Europe has been significantly expanded since 2012, further expansion is necessary to meet current and future demand. Since 2015, PEM electrolysers, which are named after the polymer electrolyte membranes (PEM) used in them, have been increasingly used and, compared to other electrolysis technologies, are better able to cope with fluctuating electricity production from renewable energies and require fewer chemicals.
Bild: Schematischer Aufbau einer Elektrolysezelle, wie sie in Wasser-Elektrolyseuren zu finden ist. Auf die Polymer-membran in der Mitte sind direkt die beiden Katalysatorschichten aufgetragen. Diese drei Schichten bilden zusammen die Membran-Elektroden-Einheit (MEA). Die Gasdiffusions-Schichten können aus unterschiedlichen Materialien bestehen. Zumeist werden feine Metallgitter oder Kohlenstoff-Papier genutzt. Außen sorgen Flussfelder für die Verteilung des Wassers in der Zelle.
The technical readiness level of PEM electrolysers is already at a very good level, but up to now these systems have been manufactured almost entirely in factory operations. In addition, the average service lifetime of the electrolysis cells in which the chemical reaction takes place is not yet at a level that enables economical operation.
Our research group is therefore working on improving the production of electrolyzers and the service life of electrolysis cells.
Our research - We are working on it!
In several industry-related research projects, we are working with our project partners on the continuous production of electrolysers. To this end, we are developing suitable inline analytics that can be used to check the quality of components during the production process. This allows us to take direct countermeasures in the event of deviations.
In order to optimize the service lifetime of PEM electrolysis cells, we focus on the special degradation phenomena within these cells. Of particular interest here is the membrane electrode assembly (MEA), the heart of every electrolysis cell. We are investigating the mechanisms and influencing factors that have a negative impact on the MEA. Our research ranges from the smallest electrolysis cells at laboratory scale to industrial electrolysers with an output of several kilowatts. The operation of a megawatt electrolyser is also planned.
By clarifying the relevant causes for the limitation of cell service lifetime and improving the production of PEM electrolyzers, we ensure that this electrolysis technology can become competitive as an important building block for a climate-friendly future.
Interested in a pioneering field of research? Optimize hydrogen production with us!
Our PhD students are working on many exciting topics, for example in the fields of microscopy, spectroscopy and cell design.
If you have successfully completed a technical, chemical or other scientific Master's degree and want to advance hydrogen research with your ideas and knowledge, apply for one of our advertised PhD positions.