Investigation of a solid oxide fuel cell integrated into an internal combustion engine with carbon capture for maritime applications

Abstract

The significance of limiting greenhouse gas emissions has grown in the maritime sector and regulations in this regard have become increasingly stringent. This leads to the need for new and more environmentally friendly power sources, and technologies to be used in ships. Fuel cells and carbon capture systems can enable ships to both meet the International Maritime Organization's emissions regulations and contribute to a sustainable environment by reducing greenhouse gas emissions. In this study, the solid oxide fuel cell is electrochemically, and thermodynamically modeled and integrated into the internal combustion engine for maritime applications. Reformed natural gas is used as fuel, so the steam reforming and the carbon capture and storage systems are also integrated into the solid oxide fuel cell and internal combustion engine power system. Integrated systems are simulated and energy, exergy, economy, and environmental analyses are carried out. The effects of solid oxide fuel cell operating temperature, current density, operating time due to degradation, and the use of hydrogen instead of natural gas on analyses results are investigated. The findings obtained in this study showed that the proposed integration could reduce carbon dioxide emissions by 76.1 per cent, while the hydrogen-fuelled alternative system could reduce carbon dioxide emissions by 96.9 per cent at an operating lifetime of 35,000 h for the solid oxide fuel cell. Given the fuel cell degradation, the average overall energy efficiencies of the systems were 44.1 per cent and 57.5 per cent, respectively, while the cost of the proposed system was 41.1 per cent lower than the hydrogen-fuelled alternative. Hydrogen-fueled alternative system was closer to the net zero target in emission and had higher efficiencies, the proposed system might be a more effective solution in the transition to the net zero target because of its lower volume and mass requirements and lower costs.