US ethanol could fuel growing methanol-capable fleet, MEMA study finds

Ethanol can use the dual-fuel engines and bunkering infrastructure built for methanol with limited modification, according to a new study published on Thursday (12 November) by the Maritime Ethanol & Methanol Alliance (MEMA), a platform of the Global Centre for Green Fuels (GCGF).

That gives shipowners a readily available fuel for a growing fleet at a time when supply of low-emission methanol remains constrained.

According to the study, Marine Ethanol: Unlocking the US Opportunity, ethanol can support the more than 300 methanol-capable vessels in service or on order, either on its own or blended with methanol.

The study adds that the US is well placed to meet shipping’s growing demand for biofuels. US plants can produce 18.5 billion gallons a year against 2025 output of 16.4 billion gallons, leaving around 2 billion gallons of spare capacity. The US already produces just over half of the world’s fuel ethanol. It exports to around 80 countries, largely through Gulf Coast terminals that are also major bunkering hubs.

International shipping burns around 300 million tonnes of fuel a year, worth an estimated USD 180 billion. In the study’s illustrative scenarios, ethanol meeting 1% of that fuel by mass would require around 1 billion gallons, well within today’s spare capacity. A 5% share by the mid-2030s would require around 5 billion gallons.

The study comes as ethanol bunkering moves from trials to commercial operation. On 28 September, Tangier Maersk completed a commercial ship-to-ship bunkering of US corn ethanol in Houston, the first publicly announced US ethanol bunkering of a deep-sea container vessel.

The International Maritime Organization, shipping’s global regulator, is expected to decide next steps on its Net-Zero Framework at an extraordinary session on 4 December, directly after MEPC 85.

The study assesses ethanol at technology readiness level 8–9: technically mature, with commercial deployment emerging. Compared with heavy fuel oil, ethanol virtually eliminates sulphur oxide emissions. It cuts nitrogen oxides by 40 to 94%, depending on engine technology, and particulate matter by 90 to 99%, without scrubbers. Its net production cost, after co-product revenue, is below USD 1 a gallon, which is low relative to other low-emission marine fuels.

The study is published by MEMA, a platform of the Global Centre for Green Fuels. ABS provided the technical analysis as Knowledge Partner. The views and recommendations in the study are those of MEMA. US ethanol producer Marquis Energy provided industry input.

Clarence Woo, Managing Director of the Global Centre for Green Fuels, said: “Ethanol is moving beyond pilots, and this study shows the United States has the production base and export infrastructure to supply shipping at scale. The next challenge is consistency. 

“As international bunkering grows, shipping needs standardised and fungible marine fuel specifications, together with traceable feedstocks and a robust chain of custody, so that ethanol from different producers and regions can be used with confidence.”

Note: The full report can be downloaded from www.green-fuels.org/us-ethanol.

Related: Maersk completes first US ship-to-ship ethanol bunkering operation

Photo credit: Global Centre for Green Fuels
Published: 13 November, 2026