We compared the electrochemical current density- The GEOR CV shows two oxidation waves with onsets of -0.56 V vs. Ag/AgCl and 0.36 V vs. Ag/AgCl. These correspond to glycerol electrooxidation on the metallic electrocatalyst surface and the oxidized electrocatalyst surfaces, respectively. Both of these potentials are less positive than that of OER at high pH values. The oxidized electrocatalyst surface is likely very stable at high current densities as well. However, it is only 0.2 V negative of the OER potential. This would limit the cell potential advantages for using GEOR paired with an HER cathode compared to the overall water splitting reaction. The metallic GEOR electrocatalyst can save up to 1.0 V by a similar comparison. We used similar j-E characteristic measurements of cathode/catholyte half-cells from three electrode CV measurements to characterize full electrolysis cells using a BPM separator. Measuring j-E characteristics for each of the half-cell reactions with respect to the same reference (here, an Ag/AgCl reference electrode) enabled a standard LLA for predicting two-electrode operation.