Model analysis on hydrogen production by hybrid system of SOEC and solar energy

We investigate the Solid Oxide Electrolysis Cell (SOEC) can convert high temperature steam into H₂ and O₂ with high efficiency. The SOEC operating temperature is very close to the temperature of solar dish engine system which heats up the water to high temperature steam. We design an advanced the hydrogen production system utilizes solar energy as the only prime energy source in which the thermal energy is provided by solar dish thermal engine subsystem while the electrical energy is supplied by photovoltaic subsystem. Energy and exergy analysis have been conducted to investigate the thermodynamic-electrochemical characteristics of the hydrogen production by hybrid system of SOEC and solar energy. The effects of some important operating parameters, such as temperature, flow rate of H₂O and current density have been studied. It is found that an increase in temperature and decrease in operating voltage can reduce the exergy loss in the hybrid system. The findings show that the difference between energy and exergy efficiency is small for the high temperature thermal energy input is only a small fraction of the total energy input. Numerical simulations are implemented for illustration and verification of the effectiveness of the solar energy.