This article presents a novel membrane-electrode-assembly (MEA) system for electrocatalytic CO₂ reduction to ethylene, achieving over 1,000 hours of stable operation at 10 A. The system, called APMA (Anion-Exchange Membrane + Proton-Exchange Membrane), uses pure water as the anolyte, eliminating the need for alkali cations and preventing carbonate formation and precipitation. The system consists of an anion-exchange membrane (AEM) at the cathode and a proton-exchange membrane (PEM) at the anode, creating an alkaline cathode environment that facilitates CO₂ reduction to ethylene while suppressing hydrogen evolution. The AEM and PEM work together to prevent anion crossover and maintain a stable electrolyte environment. The system was tested with a high-performance surface-step-rich Cu (SS-Cu) catalyst, which showed high activity for ethylene production. The APMA system achieved a 50% Faradaic efficiency towards ethylene at 10 A, with no CO₂ or electrolyte losses over 1,000 hours. The system's stability is attributed to the prevention of carbonate formation and anion crossover, which are major issues in conventional CO₂ reduction systems. The study highlights the potential of the APMA system for industrial-scale CO₂ reduction to ethylene, offering a more efficient and stable alternative to existing technologies.This article presents a novel membrane-electrode-assembly (MEA) system for electrocatalytic CO₂ reduction to ethylene, achieving over 1,000 hours of stable operation at 10 A. The system, called APMA (Anion-Exchange Membrane + Proton-Exchange Membrane), uses pure water as the anolyte, eliminating the need for alkali cations and preventing carbonate formation and precipitation. The system consists of an anion-exchange membrane (AEM) at the cathode and a proton-exchange membrane (PEM) at the anode, creating an alkaline cathode environment that facilitates CO₂ reduction to ethylene while suppressing hydrogen evolution. The AEM and PEM work together to prevent anion crossover and maintain a stable electrolyte environment. The system was tested with a high-performance surface-step-rich Cu (SS-Cu) catalyst, which showed high activity for ethylene production. The APMA system achieved a 50% Faradaic efficiency towards ethylene at 10 A, with no CO₂ or electrolyte losses over 1,000 hours. The system's stability is attributed to the prevention of carbonate formation and anion crossover, which are major issues in conventional CO₂ reduction systems. The study highlights the potential of the APMA system for industrial-scale CO₂ reduction to ethylene, offering a more efficient and stable alternative to existing technologies.