Marine high-temperature fuel cell power and propulsion system with integrated carbon capture: A techno-economic study

This study proposes a retrofit energy system for a marine diesel oil (MDO) container vessel, integrating a methanol-fuelled internal combustion engine (ICE), molten carbonate fuel cell (MCFC), carbon capture system, and organic Rankine cycle (ORC). The main goal of the paper was to reduce a large container vessel's greenhouse gas (GHG) emissions by retrofitting the traditional MDO ICE propulsion system. Comprehensive thermodynamic and economic analyses were conducted to evaluate its performance and feasibility. The system captures 93.2 % of CO₂, reducing the CO₂ emission intensity (EMI) from 358.7 to 32.1 kg/MWh. While carbon capture equipment lowers the electrical efficiency by 8.4 %, the system achieves overall electrical and exergy efficiencies of 49 % and 56 %, respectively. The system meets the vessel's propulsion demand (39.9 MW) and supplies the required 4 MW auxiliary and 6 MW heating power. The levelised cost of energy (LCOE) is 0.16 $/kWh, with fuel costs accounting for 73.5 % of the LCOE. Annual revenues from CO₂ sales and carbon credits are projected at $12.35 million, surpassing carbon capture costs.