A simplified schematics of the apparatus for the generation of pressurised hydrogen by the hydrolysis of Mg or MgH2 in acidic solutions developed by the Russian co-authors of this article is shown in Figure . Hydrogen generation takes place in reactor . Before starting the process, a solid hydrogen generating material (1a; Mg, MgH2, or a composite on their basis) is loaded in the reactor in the form of powder, granules or foil followed by filling the reactor with water (1b).