The NAUTILUS project is designed to develop and test a disruptive low-emission Genset for large passenger ships, by developing an innovative Solid Oxide Fuel Cells (SOFC) and battery hybrid to drastically reduce CO2 and non-CO2 emissions. An SOFC system design and a concept for ship integration at the Multi-MW scale was produced that yields above 60% LHV electrical efficiency at full load in beginning-of-life condition, and accounts for its operation until SOFC end-of-life. Valorization of the heat produced for ship hot water production enables a net combined efficiency of 77% (LHV). Experimental results for SOFC Large Stack Module (LSM) characterization and LSM/Battery Proof of Concept were used to calibrate design models, including specially developed energy management system. Marinization aspects were considered by experiments of SOFC-inclination and safety aspects were investigated in a HAZID analysis.
The SOFC & Battery Genset’s modular implementation was analysed with the Virtual Genset Simulator, which summarizes the design considerations and provides a basis for energy scenario simulations by shipyards. In-depth electrical and thermal vessel integration studies performed by shipyards include estimated real component genset sizing, auxiliaries, fuel supply and exhaust venting systems, as well as on-board arrangement strategies. As a result, design drawings of piping and grid arrangements as well as maintenance considerations were produced in a deck-layout of separate fuel cell- and batteries rooms. Simulations to analyse emission and energy efficiency for three different design integration scenarios were performed to identify fuel savings and emission reductions with the newly developed genset utilizing the digital twins of the shipyards developed for this purpose.
Design, manufacturing and commissioning of the SOFC system and of the battery and controls container components were completed and integrated together with the energy management system (EMS) unit in the SOFC/battery genset demonstrator, which attained its launch event at the demonstrator site on October 29th, 2024. The genset demonstrator delivered 64.6 MWh of electric power to the grid from September to December 2024 and demonstrated a peak efficiency of 61.9% (LHVDC) and 60.1% (LHVAC), significantly outperforming conventional gensets typically operating at 40 to 45% LHV.
The technology impact analyses were carried out, with a study of genset performance with future fuels showing highest electrical efficiency for LNG compared to other future fuels. The levelized cost of energy (LCOE) produced onboard is highly competitive at 0.247 EUR/kWh. The on-site emissions measurement campaign validated a 30% reduction in CO2 emissions compared to internal combustion engines (ICE) operating with heavy fuel oil (HFO), negligible methane slip and an outstanding 95% reduction in non-CO2 pollutants, even in part-load operations—an unprecedented achievement in maritime energy systems. The lifecycle assessment (LCA) with five fuels (methane, methanol, diesel, ammonia, and hydrogen) predicts a 30% lower operational global warming potential due to CO2 emission compared to the HFO ICE.
A health impact assessment was conducted from which it was estimated that shipping-related PM2.5 emissions account for up to 2.3% of premature deaths and 7.3% of childhood asthma cases in certain European port cities. These health impacts also translate into substantial societal costs, including increased healthcare expenses, reduced workforce productivity, and diminished quality of life. Implementing stricter emission control measures, such as low-sulfur fuels and the establishment of emission control areas, has the potential to reduce premature deaths related to shipping emissions by up to 50% and lower asthma cases by 30%. Additionally, advanced technologies like solid oxide fuel cells (SOFC) could cut emissions of PM2.5 NOₓ, and SO2 by over 99%, providing significant health and societal benefits.
Finally, The NAUTILUS project’s results have been widely presented in leading scientific journals and conferences for SOFC technology, battery and energy management as well as transportation research, and a novel format was introduced to the European Fuel Cell Electrolysis Forum (EFCF) with the first Sustainable Shipping Days (SSD). For an overview of the results and their exploitation and dissemination, please refer to Deliverable D8.5
