Wartsila Talking to Shipping Companies, Fuel Producers on Use of Ethanol as Marine Fuel

It would take little more than engine tuning to allow methanol engines to burn ethanol bunkers. Image Credit: Ship & Bunker

Marine engine giant Wartsila is in talks with shipping companies and fuel producers over the use of ethanol as marine fuel.

"Ethanol is a good fuel... It still contains carbon, but it can be a carbon-neutral fuel," Mikael Wideskog, Wartsila's director for sustainable fuels and decarbonization, told S&P Global Commodity Insights in a recent interview.

Brazil's Raizen, the world's largest ethanol producer from sugarcane and joint venture between Shell and Brazilian bioethanol, sugar, and energy firm, Cosan, believes that by 2030 marine ethanol demand could reach 32 million m3/year.

One drawback to ethanol is that it is not suitable as a drop in marine fuel for today's conventionally powered vessels, so like many of the candidate future fuels such as hydrogen, exsiting ships would require some technical changes before ethanol can be used in the existing fleet.

As the industry prepares for a future marine fuel mix that contains both new and a greater variety of fuels, some key design considerations are the fuel system specifications, and injectors on the engine cylinders as these typically need to be sized differently for different fuels.

Where the uptake of ethanol may have an advantage is that it has similar behavioural characteristics to methanol.

"From the engine point of view, we treat methanol and ethanol as quite equal fuels," says Wideskog, meaning the two fuels can share common technical features such as injection systems and bunker tanks.

As such, it would take little more than engine tuning to allow methanol engines to burn ethanol bunkers.

Methanol is currently a popular candidate to replace oil in the future marine fuel mix, with box shipping beheamoth Maersk among the fuel's prominent early backers.

There are currently no ethanol power ships in operation, while methanol boasts some 26 vessels in operation that are capable of burning the alternative fuel, and another 100+ and growing on the order book.