Optimum Operating Conditions for Alkaline Water Electrolysis Coupled with Solar PV Energy System

This paper investigates theoretically and experimentally the optimum operating conditions for alkaline water electrolysis coupled with a solar photovoltaic (PV) source for hydrogen generation with emphasis on the electrolyzer efficiency under different operating conditions. The PV generator is simulated using Matlab/Simulink to obtain its characteristics under different operating conditions with solar irradiance and temperature variations. A wide range of operating parameters, which include input voltage, temperature, concentration of the electrolyte, and distance between the electrodes, are considered, and their effects on the efficiency of hydrogen production process are explored. A group of performance curves for the solar-hydrogen energy system (SHES) under a wide range of operating conditions are obtained through a number of individual experimental measurements. The optimum operating conditions, which correspond to the maximum electrolyzer efficiency, are determined for the proposed SHES. The effects of the ambient temperature and the electrolyte temperature on the performance of the solar PV energy system and the hydrogen production process are also investigated.