Thermodynamical and electrochemical model of a PEM electrolyzer plant in the megawatt range with a literature analysis of the fitting parameters

In the coming years, the European Union plans to establish Proton Exchange Membrane (PEM) electrolyzers, each with a 100 MW capacity. However, the selection of their locations has not been systematically optimized to leverage potential benefits, such as utilizing waste heat from large facilities for district heating. Presently, there are hardly any corresponding system models in the literature dynamically simulating a PEM electrolyzer of this size. This paper introduces a first model approach for such systems, drawing on parameters from existing literature. It addresses the inconsistency found in the literature regarding the use of the exchange current density, which varies by a factor of 10⁹. A novel optimization process is developed by using an auxiliary parameter to fit the exchange current density with a newfound condition between the anode and cathode side. The outcome is a comprehensive model of a PEM electrolyzer plant, exemplarily adapted to the Siemens Silyzer 300.