Hitachi Zosen Corporation: PEMEL & Methanation Technologies Hitachi Zosen Corporation (HITZ) is a major Japanese industrial and engineering corporation. HITZ has developed a proton exchange membrane electrolyzer (PEMEL) technology called HydroSpring. This profile covers HITZ's hydrogen and methanation technologies as well as the alkaline water electrolyzer (AWE) and methanation technologies of its Swiss subsidiary, Hitachi Zosen Inova (HZI). Hitachi Zosen Corporation: PEMEL & Methanation Technologies