The need for clean energy as an alternative is inevitable. HHO gas has received much attention lately. In addition to electrolyte concentration, the breakthrough with a diverse electrode surface texture approach has not been extensively performed. Therefore, this study aims to determine the effects of NaOH concentration and plate surface texture on the performance of the HHO generator. In general, the increase in electrolyte concentration combined with surface texture caused an increase in output current, HHO gas production, and output temperature. As for the applied voltage variation with various surface textures, the increase in output current, HHO gas production, and output temperature also took place, similar to the case of increasing NaOH concentration. Either an increase in electrolyte concentration or an increase in applied voltage triggers faster ion movement, leading to an increase in conductivity, thus effectively assisting the electrolysis of water. Regarding the output current and HHO gas production, the textured surface had a much higher value than the plain surface in terms of increasing NaOH concentration or applied voltage variations. However, according to the R2 results, the linear surface has a stronger relationship with the output current and HHO gas production than the cross surface. In the case of the output temperature, the linear surface was slightly lower than the cross surface. It is possibly due to impurities in the electrolyte solution that contaminate the electrode surface, resulting in a lower output temperature on the linear surface.

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