Techno-economic assessment of decentralized low-carbon power plants based on solid oxide fuel cell equipped with calcium looping carbon capture

Abstract

Integrating solid oxide fuel cells (SOFCs) with carbon capture technologies aligns with the intention to decarbonize the electricity sector. This study explores two configurations of SOFCs combined with calcium looping (CaL) carbon capture technology (SOFC/CaL): one with auxiliary heaters and another with additional fuel to supply the energy required for the carbon capture process. Results indicate that the electrical efficiency of the SOFC/CaL system is approximately 26 % lower than that of a standalone SOFC, though the overall efficiency (considering both electricity and heat as products) remains comparable. However, CO₂ emission is 314.7 kg/MWh for standalone SOFC, 125.8 kg/MWh for SOFC/CaL equipped with auxiliary heaters, and 22.4 kg/MWh for SOFC/CaL retrofitted with additional fuel. The scale of the SOFC and the fuel price significantly affect the carbon capture economy and the required CO₂ tax for cost parity. For a 10 MW plant with a fuel cost of 10 USD/GJ, the levelized cost of electricity is estimated at 66.7 USD/MWh for the standalone SOFC and 82.5 USD/MWh for the SOFC/CaL. A CO₂ tax of 39–53 USD/tCO₂ is necessary to achieve cost parity.