Advances in steam electrolysis for green hydrogen production: Current status and future outlook

Abstract

As renewable energy sources increasingly dominate electricity generation, hydrogen is emerging as an important energy carrier, particularly through electrolysis. Among the various methods, steam electrolysis, in particular via solid oxide electrolysis cells (SOEC) and high-temperature proton exchange membranes (PEM), is gaining ground due to its efficiency and potential for large-scale hydrogen production. The global push for green hydrogen is supported by various government policies aimed at reducing carbon emissions and promoting the integration of renewable energies. Countries are investing in R&D to reduce costs and improve electrolyzer reliability. Analysis of solid oxide electrolysis (SOEC) cells and proton exchange membrane (PEM) steam electrolysis reveals distinct operational characteristics and applications. SOECs excel in high-temperature environments, while PEM technology is more suited to low-temperature applications. This study examines the key cell components of both technologies, describing their material properties and degradation issues. A comprehensive review of the impact of operational conditions on cell efficiency and longevity for both technologies is carried out. The comparative analysis of the two electrolysis methods highlights their unique advantages and limitations, shedding light on their specific application contexts. Given the relatively limited investigation into PEM steam electrolysis, this review concludes by suggesting that future research should focus on optimizing cell components, integrating renewable energy sources and investigating the utilization of seawater as a precursor for the generation of green hydrogen.