German speciality chemicals company Evonik Industries AG (<a href="https://www.boerse-frankfurt.de/equity/evonik-industries-ag" target="_blank">ETR:EVK</a>) announced it has started building its pilot plant for reinforced anion exchange membranes (AEM) in Marl, Germany, targeting an annual output that will support 2.5 GW of electrolysis capacity for hydrogen production.