Investigation and comparative evaluation of a hybridized marine engine powered by eco-friendly fuels including hydrogen

International trade volumes have grown due to acceleration of marine transportation of goods between continents. However, there is a concomitant increase in fossil fuel consumption and adverse environmental impact. This paper presents a new design of marine engines comprising of gas Brayton cycle, solid oxide fuel cell, and two organic Rankine cycles to replace two-stroke internal combustion engines. Hydrogen, methane, dimethyl ether, ethanol, and methanol are potentially selected as green fuels. In addition, liquified natural gas is used for cooling processes. This integrated hybridized marine engine is thermodynamically analyzed using the Aspen Plus software to assess its performance energetically and exergetically. It is found that the engine's total power is boosted by 33% to an average of 15758 kW with average energetic and exergetic efficiencies of 38% and 46%, respectively. The maximum power is fulfilled using all sustainable fuel blends to reach 16087 kW with a maximum carbon emission reduction of 83% and minimum specific fuel consumption. The proposed engine has better performance and less environmental impact, which is a more convenient choice than traditional engines. [Display omitted] •Five alternative fuels are chosen with different concentrations.•Integrated hybrid marine engine produces a total power of 16087 kW by 33% increase.•Engine runs at a 38% energy efficiency and 46% exergetic efficiency.•Alternative fuels can reduce carbon emissions by more than 80%.•New engine fuel consumption is reduced by more than 55%.