The durability of zero-gap membrane electrode assembly (MEA) for electrochemical conversion of CO2 relies on the stability of cell materials including electrodes, membranes and ionomers. The degradation of electrodes and the AEM membrane contributes to cell potential increase during operation. This report analyzes the energy efficiency of Cu-based electrocatalysts coupled with IrOx and NiFeOx anodes in MEA cells to convert CO2 to C2+ products. The cell potential growth of 8.4 mV h-1 for 155 h at a current density of 150 mAcm-2 in 0.1M KHCO3 for Cu nanoparticles (Cu NPs) cathode and IrOx anode, is evaluated to be the sum of the overpotentials recorded on the cathode (418 mV), the anode (62 mV) and across the membrane (384 mV). The potentials on both electrodes are correlated with the loss in electrochemical active surface area (ECSA) accounting for the loss of active sites during the 155 h durability test. The 418 mV overpotential recorded on the Cu NPs electrocatalyst corresponded to an 18% loss of ECSA, while the 62 mV on the IrOx anode corresponded to 8% ECSA loss in 0.1M KHCO3 at 150 mA cm-2. NiFeOx anode together with Cu NPs cathode under the same operation conditions demonstrated 28% ECSA loss for 100 h cell run. The overpotential recorded on these electrodes have been understood to be due to the chemical dissolution and mechanical degradation of electrode materials from the different electrodes under operation conditions when simulated experiments were conducted to mimic the electrochemical CO2 reduction conditions within the electrolyzer. Particularly, when GDE sprayed with the Cu NPs was heated at 80 degrees celcius in 0.1M KHCO3 while bubbling air (imitating CO2 pressure), significant mechanical loss (76%) was observed alongside chemical dissolution (21%) which was amongst other experiments supporting the forms of degradation observed on the electrodes surface. Thus, the anodic electrolyte after 155 h durability test in 0.1M KHCO3 at 150 mA cm-2 was analyzed for trace amounts of potential Cu NPs, Ir, Ni, and Fe elements through the ICP-OES measurements. The analysis revealed that the 18% ECSA loss of Cu NPs and 8.3% ECSA loss of IrOx corresponded to 3% Cu loss and 6% Ir loss respectively. The percentage Cu NPs loss determined through the ICP-OES is understood not to reflect the total electrode material loss because of the compact nature of the zero-gap MEA. This indicates that the 3% Cu NPs loss corresponds to the dissolution of the native oxides into the electrolyte during cell operation, confirming that the electrode degradation is both due to both chemical dissolution and mechanical stress under the electrolyzer operation conditions. These insights gained offer new avenues of research in developing more rigid and stable electrodes-support interactions for energy efficient, stable and durable operation in converting CO2 to sustainable chemicals.