Electrolyte concentration, applied current, cell connection, operating time, temperature of electrolyte, and voltage had an impact on hydroxy (HHO) rate produced from different types as dry, wet and hybrid. The maximum produced HHO for dry, wet and hybrid cells were 1250, 1376 and 1360 ml/min., respectively at 20% NaOH concentration uses current of 60 A using [10C10A5N] configuration. Hybrid cell reaches the stable condition after 45 min and can produce HHO at a maximum rate of 1288 ml/min at 20 gm NaOH concentration with flow current of 21.8 A. The electrolyte temperature was raised to 53 °C at a concentration of 20 gm NaOH and then held constant in 30 min. for dry type. Wet cell' HHO production reaches to the peak value at 1375 ml/min at 20 gm NaOH concentration with flow current of 27 A and achieves a stable state after 90 min. Electrolyte temperature climbed to 58, 53 and 52 °C at a concentration of 20 gm NaOH and then stayed steady after that in wet, hybrid and dry cells, respectively. The improved cells's efficiencies were 74.72, 73.85 and 75.45% for hybrid, dry and wet cells producing 389, 349 and 402 ml/min at a current of 14 A and 6.25 V. Dry cell is preferred over wet and hybrid cells because it is less expensive.