Alternative Marine Fuels: A Pathway to Carbon-Neutral Shipping
Amirulaminfirdaus Mohd Yusof · Corresponding Author
Faculty of Maritime Studies, Universiti Malaysia Terengganu
Correspondence: s65535@ocean.umt.edu.my
Abstract
Shipping decarbonization requires fuel-selection decisions that account for emissions across the full fuel lifecycle as well as machinery adaptation, economic feasibility, shipboard safety and bunkering availability. This study evaluates liquefied natural gas (LNG), methanol, ammonia, hydrogen and advanced biofuels using a seven-criterion weighted-sum multi-criteria decision analysis (MCDA), supported by a structured technical literature synthesis. Criteria are well-to-wake CO₂ reduction, NOₓ or SOₓ reduction, volumetric energy density, engine compatibility, fuel cost, operational safety and supply-chain maturity. Under the stated scenario inputs and weights, the ranking is advanced biofuels (0.752), LNG (0.669), methanol (0.655), ammonia (0.559) and hydrogen (0.539). The figures are reproduced from the declared input matrix, including fixed five-point denominators for qualitative scores. A five-scenario sensitivity analysis reveals that LNG ranks first if the weight on cost rises to 0.40, while advanced biofuels retain first place under the carbon- and safety-priority scenarios. These results are conditional decision scores rather than validated lifecycle emission factors or a fleet-wide fuel hierarchy. The evidence indicates that drop-in biofuels may support near-term deployment where credible feedstock certification is available; low-carbon methanol and hydrogen-derived fuels require expansion of renewable production and distribution; and LNG requires scrutiny of methane slip and upstream methane leakage. Fuel transitions should therefore be evaluated by verified pathway-specific well-to-wake emissions, ship operational profiles and risk controls rather than nominal fuel identity alone.
Acknowledgement
The author gratefully acknowledges Universiti Malaysia Terengganu (UMT) for its institutional support and for providing the facilities, resources, and conducive research environment necessary for the successful completion of this study.
Conflict of interest
No competing-interest declared
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