US ethanol could help fill fuel gap for methanol-capable ships, study finds

The United States has about two billion gallons of spare annual ethanol production capacity that could help supply a growing fleet of methanol-capable ships, according to a study released on 12 November 2026 in Singapore. The Maritime Ethanol & Methanol Alliance (MEMA) found that compatible dual-fuel engines and bunkering infrastructure built for methanol could be adapted for ethanol with limited modifications, giving shipowners another option while supplies of low-emission methanol remain constrained.

How much ethanol could the US supply to shipping?

The study puts US ethanol production capacity at about 18.5 billion US gallons a year. The US Energy Information Administration recorded output of about 16.5 billion gallons in 2025, broadly supporting the study’s estimate of two billion gallons of spare capacity. The study says the US exported 2.18 billion gallons to around 80 countries in 2025, with most shipments leaving through Gulf Coast terminals that also serve major bunkering markets.

The alliance estimates that supplying 1 per cent of international shipping’s annual fuel consumption by mass would require about one billion gallons of ethanol. A 5 per cent share would require roughly five billion gallons, exceeding the spare US capacity identified in the study. These are illustrative scenarios based on fuel mass. Ethanol contains more energy per kilogram than methanol and less than marine gas oil, so the fuel volume needed for a voyage depends on the fuel it replaces and the vessel’s consumption.

Can methanol-capable ships run on ethanol?

The report identifies more than 300 methanol-capable vessels in service or on order as a potential market. It examines the use of ethanol on its own or blended with methanol and expects commercial ethanol-capable engine offerings from 2027. The American Bureau of Shipping (ABS) provided technical analysis. The findings and recommendations were published by MEMA, an initiative of the Singapore-based Global Centre for Green Fuels.

A.P. Moller–Maersk announced on 28 September that its dual-fuel container ship Tangier Maersk had received US-produced corn ethanol in Houston. Maersk described the operation as the first commercial ship-to-ship ethanol bunkering of a deep-sea container vessel in the United States. The company did not disclose the quantity supplied.

What will determine wider use of marine ethanol?

Global Centre for Green Fuels Managing Director Clarence Woo said wider adoption would require common marine fuel specifications and traceability from feedstock to delivery. Lifecycle emissions accounting is also a commercial issue. The US National Corn Growers Association said the International Maritime Organization (IMO) had yet to approve a carbon intensity value for US corn ethanol. The study’s estimated emissions reductions depend on the production pathway and the fuel used for comparison.

FAQs

How much spare US ethanol capacity did the study identify?

About two billion US gallons a year, based on the difference between annual production capacity and 2025 output.

Can ethanol use existing methanol bunkering infrastructure?

The study found that infrastructure built for methanol could handle ethanol with limited modifications. It identified common fuel specifications and feedstock traceability as priorities for wider use.

Which ship received US corn ethanol in Houston?

Tangier Maersk, a dual-fuel container ship capable of using alcohol fuels, received the ethanol in a commercial ship-to-ship transfer.