Optimization of a wet-cell electrolyzer for efficient oxyhydrogen (HHO) gas production: a step towards sustainable green energy solutions

The urgent need for sustainable energy solutions drives innovation in clean fuel technologies. Oxyhydrogen (HHO) gas, produced through water electrolysis, presents a promising green energy vector. While often studied in dry-cell configurations, wet-cell electrolyzers offer advantages for efficient, scalable production but require further optimization. This study systematically investigates the design and operational parameters of a wet-cell HHO generator to maximize efficiency. Four distinct configurations (Alpha, Beta, Gamma, Delta) were constructed, varying in electrode cross-sectional area (75 × 75 mm² vs. 150 × 150 mm²), plate configuration (18 vs. 20 plates), and tested at different potassium hydroxide (KOH) concentrations (10 and 20 g/L). Performance was evaluated based on HHO flow rate, specific energy consumption, and overall system efficiency. Experimental results demonstrate that the Delta generator significantly outperformed all other designs. It achieved a peak HHO flow rate of 3.4 L/min with a specific energy consumption of 3.1 kWh·m⁻³ and a notable overall system efficiency of 59.74%. In contrast, the Alpha, Beta, and Gamma generators attained lower efficiencies of 12.7%, 23.86%, and 41.9%, respectively. The superior performance of the Delta design is attributed to its optimized combination of a larger electrode area, which reduces current density and associated overpotentials, and an effective electrode configuration that maximizes active surface area and thermal management. This study conclusively identifies optimal electrode geometry and electrolyte management as critical drivers for efficient HHO production. The optimized wet-cell electrolyzer presents a sustainable and practical technology for on-demand green hydrogen production, with direct potential applications as a combustion enhancer or a storage solution for intermittent renewable energy, contributing to the advancement of sustainable energy systems.