Safety analysis of proton exchange membrane water electrolysis system

This study presents a novel causality model for the safety analysis of proton exchange membrane water electrolysis (PEMWE). The model is based on the integration of computational fluid dynamics (CFD)-based and Bayesian network (BN)-based modeling approaches. The model is aimed at analyzing evolving hazard scenarios, such as gas permeation/crossover (GP) during PEMWE based on fluid dynamics and electrochemistry of electrolysis. The probabilistic domain is employed to model these scenarios using a BN-based technique to assess the likelihood of hazardous scenario occurrence for the first time. A sensitivity analysis was performed, and it was found that operating pressure is the most significant contributor to GP. Operating cell voltage and pressure are two dominant parameters that can trigger GP with the largest likelihood of 87%. Therefore, gas combinators serve as the most effective safety barrier in avoiding the formation of hazardous H2/O2 gas mixtures. This work provides a robust framework for analyzing accident scenarios and developing safety management strategies. It is expected that this model will help in the development of safer PEMWE systems, which is of great importance for various industrial applications.