As the shipping industry embraces alternative fuels to reduce carbon emissions, carriers are evaluating the advantages and limitations of liquefied natural gas (LNG) and methanol. Both fuels are available in “grey” (fossil-based) and “green” (sustainably sourced) variants, but their potential for emissions reduction differs significantly.
Advantages of LNG
LNG offers an immediate reduction in carbon dioxide (CO2) emissions of approximately 20% compared to traditional heavy fuel oil, even in its “grey” form. This initial tank-to-wake benefit makes LNG an attractive transitional fuel, giving carriers time to develop supply chains for green synthetic LNG (SNG).
However, the 20% CO2 savings are subject to debate. Critics argue that upstream emissions—resulting from gas extraction, transportation, and liquefaction—can significantly reduce LNG’s overall environmental benefits when considered from a holistic well-to-wake perspective.
Challenges with Methanol
Unlike LNG, grey methanol provides no direct CO2 reduction compared to conventional fuels. Methanol’s viability as a sustainable option hinges on the availability of green methanol, derived from renewable sources, from the outset. Recent concerns about the limited supply of green methanol have led some carriers, including Maersk, to reassess their reliance on methanol alone and pivot towards LNG.
Outlook
The choice between LNG and methanol reflects the trade-off between immediate benefits and long-term sustainability. While LNG offers a quicker reduction in emissions, methanol’s potential lies in its future scalability with green production. These considerations underscore the complexity of the maritime industry’s transition to greener fuels.
