Design And Experimental Evaluation of a Compact Alkaline Water Electrolyzer for Hydrogen Production

This study develops a compact alkaline water electrolyser for small-scale hydrogen production, utilising a transparent acrylic chamber, stainless steel electrodes, and 25% NaOH electrolyte. Experimental results confirmed hydrogen and oxygen generation at ~0.05 L/min with ~50% Faraday efficiency, limited by low current density (~20 mA/cm²). Optimisation strategies, including Ni-Mo electrodes, 30% NaOH, and 60°C operation, could enhance efficiency to ~65–70% and yield to ~0.15 L/min. Compared to proton exchange membrane (PEM) electrolysers, the system offers lower costs (~₹15,000 vs. ₹1,00,000/kW) but reduced flexibility. Hydrogen storage challenges were addressed with metal hydride and high-pressure solutions. The cost-effective, portable design is ideal for educational and renewable energy applications, with potential for industrial scalability upon optimisation. This work advances low-cost hydrogen production, supporting sustainable energy transitions.