Thermodynamic analysis of a high-temperature hydrogen production system

Abstract

Using clean energy resources is considered as a major solution to global warming. Hydrogen is one of the most popular clean and renewable fuels, which has widely been addressed by researchers in different contexts from additive fuel of internal combustion engines to pure feed of fuel cells. Hydrogen production is also one of the most interesting fields of study and extensive effort has been devoted to finding high-performance, fast, and economical approaches in this field. In this study, a novel high-temperature steam electrolyser system with an integrated solar Brayton cycle core is proposed and numerically simulated for hydrogen production. Energy and exergy analyses were carried out to gain better perception of the performance of the system and Rankine and Organic Rankine Cycle (ORC) were integrated with the main core to improve its efficiency. The inuences of different parameters such as turbine inlet temperature, inlet heat flux from the sun, and compression ratio as well as the used organic fluid were investigated based on the first and second laws. Results showed the high performance of the proposed system with more than 98% energy efficiency in hydrogen production besides its simplicity of use. The highest exergy destruction occurred when the power generation system absorbed sun heat ux (more than 54%) and the performance of the system could be enhanced by improving the heat absorbing technology.