Volume 41: Energy Transitions toward Carbon Neutrality: Part IV

Thermodynamic Analysis of Cerium-Based Solar Thermochemical Cycle for Carbon Monoxide Production Yibiao Long, Fan Jiao1, Shiying Yang, Taixiu Liu, Qibin Liu

Abstract

Solar thermochemical decomposition of CO2 for fuel production is a promising pathway to achieve efficient and stable solar energy applications. Among these methods, Ce-based two-step thermochemical cycles have received increasing attention. To date, a comprehensive thermodynamic assessment of such thermochemical cycle is still lacking, especially in terms of exergy. In this study, a new exergy analysis model for the solar Ce-based thermochemical cycle is developed, with the aim of exploring the potential to improve efficiency according to irreversibility distribution. Through a careful study of the relation between the three independent variables (reduction temperature T_H, Oxidation temperature T_L, and pressure P) and efficiency, we put forth new strategies to reduce various energy and exergy losses. Based on the permutation algorithm, we find the operating conditions with the lowest irreversibility, which results in a 141% improvement in energy efficiency and a 91% improvement in exergy efficiency compared to the highest efficiency case.

Keywords Solar energy, Thermochemical cycles, Fuel production, Exergy analysis