Innovative heat source utilisation for calcination in SOFC-driven calcium looping: An exergy and thermodynamic evaluation of afterburner-based calcination for optimal CO2 capture

Abstract

The integration of Solid Oxide Fuel Cells (SOFC) with Carbon Capture technologies has shown promising potential for sustainable energy production and emissions reduction. However, the coupling of Calcium Looping (CaL) with SOFC systems, particularly fuelled by natural gas, remains underexplored. This study investigates two novel configurations of SOFC-CaL integration, leveraging their high-temperature operational compatibility to enhance system efficiency while capturing CO₂. Through rigorous thermodynamic modeling, energy, and exergy analyses, this work provides key insights into system performance and design and practical feasibility. The results reveal that integrating CaL with SOFC systems can achieve up to 95 % CO₂ capture efficiency, significantly reducing CO₂ emissions from 333.2 kg/MWh (basic SOFC setup) to just 26.4 kg/MWh in the most optimised configuration. Total system efficiency improves to 78 %, driven by effective heat recovery from exothermic reactions in the carbonator. However, exergy efficiency slightly declines due to heat transfer challenges and increased irreversibility in high-temperature components such as the afterburner and calciner. A comparative analysis of the two configurations demonstrates that a boosted afterburner design offers superior overall efficiency and CO₂ capture but requires additional fuel consumption. Beyond technical performance, this study highlights the scalability and economic potential of SOFC-CaL systems for decentralised power generation and industrial applications. The integration approach can facilitate cost-effective CO₂ capture and efficient energy recovery, making it a viable candidate for practical deployment. The findings establish a robust framework for future research and provide practical insights into the development of high-performance, economically feasible energy systems aligned with global decarbonisation goals.