TOWARD ZERO-CARBON SHIPPING IN MALAYSIA: A COMPARATIVE ANALYSIS OF WTT AND TTW EMISSIONS

Siti Marsila  Mhd Ruslan; Kasypi Mokhtar; Wan Nurdiyana Wan Mansor; Anuar Abu Bakar

doi:10.46754/jml.2025.08.002

Authors

Siti Marsila Mhd Ruslan Universiti Malaysia Terengganu https://orcid.org/0000-0002-6050-9883
Kasypi Mokhtar Universiti Malaysia Terengganu
Wan Nurdiyana Wan Mansor Universiti Malaysia Terengganu
Anuar Abu Bakar Universiti Malaysia Terengganu

DOI:

https://doi.org/10.46754/jml.2025.08.002

Keywords:

WTT, TTW, Malaysia, Decarbonisation , Shipping

Abstract

The maritime sector in Malaysia is at a critical juncture in its pursuit of zero-carbon shipping, which requires a strategic shift toward cleaner fuel alternatives. This study conducts a comparative analysis of Well-to-Tank (WTT) and Tank-to-Wake (TTW) emissions for six alternative marine fuels namely liquefied natural gas (LNG), methanol, biofuels, green ammonia, hydrogen and shore power. Drawing on internationally recognised emission factors and contextualised with Malaysia’s energy profile, the analysis reveals significant variations in emissions distribution across fuel types. Fuels such as green ammonia, hydrogen, and shore power exhibit zero TTW emissions, positioning them as long-term solutions, while biofuels offer a viable transitional pathway with a balanced emissions profile. Conversely, LNG and fossil methanol remain TTW-dominant and offer limited GHG reduction. The study presents a policy-oriented fuel selection framework, emphasising the importance of aligning fuel strategies with national decarbonisation goals, grid decarbonisation progress, and infrastructure readiness. The findings aim to support Malaysia’s transition towards a sustainable and climate-resilient maritime sector.

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