Dynamic modeling of a solar hydrogen system under leakage conditions

Dynamic behaviors of an integrated solar hydrogen system have been modeled mathematically, which is based on a combination of fundamental theories of thermodynamics, mass transfer, fluid dynamics, and empirical electrochemical relationships. The model considers solar hydrogen system to be composed of three subsystems, i.e., solar cells, an electrolyzer, and a hydrogen tank. An additional pressure switch model is presented to visualize the hydrogen storage dynamics under a leakage condition. Validation of the solar hydrogen model system is evaluated according to the measured data from the manufacturer's data. Then, the overall was simulated by using solar irradiation as the primary energy input and hydrogen as energy storage for one-day operation. Finally, electrical characteristics and efficiencies of each subsystem as well as the entire system are presented and discussed. (C) 2008 Published by Elsevier Ltd. on behalf of international Association for Hydrogen Energy.