Comparative study of CO2 capture strategies in optimized MCFC-based power systems: Performance, cost, and environmental perspectives

The urgent need for CO2 reduction has accelerated research into carbon capture technologies. Molten carbonate fuel cells (MCFCs) offer an efficient pathway for both power generation and CO2 separation. This study presents a comprehensive technical, economic, and environmental assessment of six optimized MCFC-based power plant configurations, each integrated with different CO2 capture technologies: calcium looping (CaL), cryogenic CO2 capture (CCC), proton exchange membrane electrolyzer-based CO2 capture (PECC), oxygen membrane-based CO2 capture (OMCC), and vanadium chlorine-based CO2 capture (VCC). Simulations were conducted in Aspen Plus, evaluating thermodynamic performance, economic feasibility, and environmental impact. The results indicate that CaL achieves the highest CO2 capture efficiency (95 %), leading to an emission index as low as 110.2 g CO2/kWh, while MCFC alone emits 457.1 g CO2/kWh. The VCC and OMCC configurations demonstrate superior energy integration, achieving net electrical efficiencies of 53.5 % and 51.4 %, respectively. However, PECC exhibits the highest Levelized Cost of Electricity (LCoE) at €0.3547/kWh, primarily due to its significant power consumption of 35.7 MW (∼24.9 % of MCFC output). The CaL system, despite its high efficiency (86.5 % CHP), incurs a 21.6 % cost increase compared to the MCFC baseline. A multi-objective optimization approach was employed to identify the most balanced system, considering efficiency, cost, and CO2 capture effectiveness.The findings highlight the trade-offs between energy efficiency, capital costs, and emissions reduction, offering strategic insights for the development of low-emission power plants. This study advances the feasibility of hybrid MCFC-CCS systems, demonstrating their potential for near-zero emissions while maintaining economic viability.