Hydrogen production by solar energy: Optimization of the plant “solar array + electrolyzer”

Abstract

The optimization of the performance of a plant consisting of a solar photovoltaic converter and a water electrolyzer has been theoretically analyzed. It is shown that the criterion of the maximum productivity of the plant coincides with that of the operation of a solar array at the point of maximum power. The algorithm of design optimization of the system has been developed allowing the ratio of the number of the series-connected solar cells to that of the electrolysis cells at given solar radiation power density to be found. The regimes of switching the number of series-connected solar cells and electrolysis cells to maintain the maximum running capacity of the plant have been computed for the operation of the system at varying solar radiation power density. A program has also been compiled for the operation of the system without automatic regime switching, and the parameters effecting the maximum integral daily capacity have been computed. The optimum relation between the solar array area and that of the electrolyzer electrodes, providing the maximum capacity of the system per unit of the investment, has been calculated with reference to the relation of the cost of unit solar cell area to that of the electrolyzer electrode.