“…In [73], the safety of the alternative marine fuels was also evaluated, considering criteria such as the fuel density, auto-ignition temperature, flammability limits, stoichiometric air-fuel ratio, octane and cetane numbers. It should be noted that recent studies identified hydrogen as the most environmentally friendly alternative marine fuel, supporting the need to produce hydrogen by renewable energy sources [56,66,73,74]. Along the same lines, it is also critical for alternative fuels (e.g.…”