EXPERIMENTAL AND ENERGETIC ANALYSIS OF GREEN HYDROGEN PRODUCTION FROM A SOLAR-WIND HYBRID SYSTEM BY ELECTROLYSIS.
green hydrogen, electrolysis, hybrid system.
The growing need to decarbonize the energy matrix has driven the development of sustainable routes for the production of green hydrogen. In this context, this dissertation experimentally and energetically evaluated hydrogen production by electrolysis integrated into a hybrid solar-wind system. Two electrolyzers were studied under different voltages (2 to 6 V), analyzing current, power, current density, specific energy consumption, electrolyzer efficiency, and faradaic efficiency. Among the electrodes analyzed, the Nickel Flynet mesh electrode with coating showed the best electrochemical performance. Electrolyzer 1 stood out for its higher efficiency and lower energy consumption, especially at 2 V, where it presented an efficiency of 50.09%, a specific consumption of 66.54 kWh/kgH₂, and a faradaic efficiency between 79% and 82%. Conversely, at 6 V, specific consumption exceeded 170 kWh/kgH₂, with efficiency decreasing to below 20%, highlighting the increase in ohmic losses and overpotentials at high current densities. The use of a membrane in Electrolyzer 2 reduced energy consumption and simultaneously increased energy and faradaic efficiency, with a more significant impact at 2 V. The hybrid system generated 19.57 kWh, enabling the experimental production of 0.288 kg of hydrogen. An overall efficiency close to 50% was obtained, a value consistent with the electrolyzer's efficiency. Modeling in DWSIM validated the mass and energy balances, showing agreement with the experimental results. Statistical analysis of triplicate retests indicated low data dispersion, confirming experimental repeatability. The results demonstrate the technical feasibility of integrating renewable sources with electrolysis for green hydrogen production.