Performance and Durability of a 50-kW Proton Exchange Membrane Water Electrolyzer using Various Fluctuating Power Sources

Scaling up water electrolyzers for green hydrogen production poses challenges in predicting megawatt-to gigawatt (MW/GW)-class system behavior under renewable energy power fluctuations. A fundamental evaluation is warranted to connect the characteristics of W- to kW-class laboratory electrolyzers with those of MW- to GW-class systems in practical applications. This study evaluates a 50 kW-class proton exchange membrane water electrolyzer with 30 cells using an accelerated degradation test protocol, a simulated renewable energy power and a constant current of 800 A (1.33 A cm− 2 ), and the results show average degradation rates per cell of 40.4, 27.2, and 5.6 μV h− 1 , respectively. Evidently, a voltage as approximate indicator exists for each cell to effectively suppress degradation. Durability tests reveal reductions in anode catalyst loading on the membrane electrode assemblies and inhomogeneous oxidation of the anode current collector. The findings contribute to predicting the stacking performance of electrolyzers for practical applications.