The IDTechEx report projects significant growth in the electrolyzer component sector, attributing it to the expanding green hydrogen industry, with a projected market value of US$10.1 billion by 2034. The global transition towards hydrogen use in various sectors is accelerating, driven by efforts to decarbonize where direct electrification is challenging. Green hydrogen, produced via renewable-powered water electrolysis, is seen as a leading solution, with investments aimed at establishing gigawatt-scale production capacities by 2030. The report emphasizes the critical role of materials and components in electrolyzer technologies, aiming to enhance efficiency, longevity, and reduce reliance on scarce materials. The report delves into the four main water electrolyzer technologies – alkaline, proton exchange membrane, anion exchange membrane, and solid oxide electrolyzers. It provides market forecasts, quantifying material and component demand, and highlights the need for advancements to support the green hydrogen revolution. The focus is on enhancing electrolyzer technologies to reduce emissions in heavy industry and transportation, improve energy security, and create new market opportunities in energy storage and sector coupling. Each electrolyzer technology is analyzed in detail, showcasing the utilization of widely available materials in alkaline water electrolyzers, the management of scarce materials in proton exchange membrane electrolyzers, the pursuit of high stability in anion exchange membrane electrolyzers, and the high-temperature ceramic innovation in solid oxide electrolyzers. The report discusses key materials and components such as membranes, catalysts, electrodes, and coatings, offering insights into current and future states along with potential innovations and commercial case studies. Overall, the report underlines the advancements in electrolyzer technologies towards more sustainable and efficient solutions, supporting the transition to green hydrogen and the decarbonization of various sectors.