In one line
Mature hydrogen electrolyser technology using a liquid alkaline electrolyte (typically KOH), lowest capex per kW.
What it means
Alkaline electrolysers are the oldest commercial hydrogen production technology, using a potassium hydroxide (KOH) liquid electrolyte. They dominate 2026 global electrolyser capacity (~70% market share) with the lowest capex of any green-hydrogen technology ($600–$900/kW). Trade-offs: slower ramp than PEM, lower current density, larger footprint per kW. Best fit for steady-state operation at utility-scale green hydrogen projects.
Related terms
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