Traditional water electrolyzers usually require large overvoltages for splitting water into hydrogen and oxygen due to ohmic resistances, electrode overpotentials, and thermodynamic requirements. One of the most promising concepts in electrolyzer design is the hybrid dual-electrolyte water electrolyzer. This type of system takes advantage of the pH gradient between electrodes whereby a theoretical potential of around 0.4 V vs. SHE is possible. While the traditional electrolyzer operates at 1.23 V, the hybrid electrolyzer operates at voltages as low as 0.8 V, as shown in a recent work by Chen et al. In order to fully understand the mechanisms of this type of system, it is important to perform a multi-physics model that would predict the behavior of a hybrid dual-electrolyte water system across a specified set of parameters. The modelling approach done in this study allows describing a range of dual-electrolyte water systems. The study takes into account the dependence of the electrical performance on structural parameters and operating conditions of the electrolyzer. The developed multi-physics model was solved using COMSOL Multiphysics^Ⓡ simulation software. The simulation tool was also used to compare the performance of a single- (both acidic and alkaline) and dual-electrolyte system. The analysis of the results showed dual-electrolyte systems having superior performance over their traditional counterparts and that improved electrolyzer operating strategies can be identified with the developed simulation study.