Revolutionizing Marine Power: Methanol Dual-Fuel Engines

149

Field Test with Damen Shipyards Group

Caterpillar Marine, the marine unit of US-based engine maker Caterpillar, will conduct a field test of its methanol dual-fuel engine with Damen Shipyards Group in 2026.

The engine maker claims that it will target “the highest methanol substitution while meeting regulated emissions” in its methanol dual-fuel engine.

“Our design approach is to meet regulated emissions in both diesel-only mode as well as dual-fuel [methanol] mode. We are working toward the largest energy substitution of methanol while meeting emission standards,” Watson told ENGINE.

Combustion Engine Dynamics

In methanol-powered combustion engines, a small amount of pilot fuel, like diesel, is necessary for ignition due to methanol’s slower burn rate compared to fossil marine fuels. Typically, the pilot fuel accounts for 5% of the fuel mixture, with the remaining 95% being methanol, as stated by the classification society DNV.

“The larger the percentage of methanol that we can use in place of diesel will provide the maximum potential to reduce greenhouse gas emissions,” Watson added.

Maximizing the percentage of methanol used in place of diesel offers significant potential to reduce greenhouse gas emissions. For example, a 28-meter tugboat cruising at eight knots requiring 600 kilowatts (kW) of propulsion power could see more than 70% of its energy needs met by methanol instead of conventional fuels. Methanol substitution can increase further at higher power levels.

“We know many customers who utilize our high-speed marine engines will have significant time in lower load ranges, so having only good performance at high loads won’t benefit them,” he said.

Versatility in Fuel Use

The dual-fuel engine can also run on conventional fuels and biofuel blends, apart from methanol. Biofuel blends, or HVO, can also be used as pilot fuel, Watson said.

Caterpillar Marine is seeing “general interest” across all vessel segments, some smaller segments are “leading the charge,” Watson said. This includes offshore vessels, tugs, salvage and dredging vessels.

Did you subscribe to our daily Newsletter?

It’s Free! Click here to Subscribe

Source: Engine