Oak Ridge dual fuel combustion system enables 75% methanol operation

A dual-fuel combustion strategy developed in a Caterpillar marine engine at DOE’s National Transportation Research Center at Oak Ridge National Laboratory shows methanol can efficiently power inland and coastal vessels.[Photo: Genevieve Martin/ORNL, U.S. Dept. of Energy]

Oak Ridge National Laboratory (ORNL) reports that a methanol dual fuel combustion system it has developed in collaboration with Caterpillar Inc. has produced significant progress, with clear relevance for inland and coastal marine vessels.

Methanol is typically produced from natural gas, an abundant domestic resource, and converting it into a liquid allows easier storage and handling. However, methanol does not ignite easily, creating a barrier for vessels that rely on compression-ignition diesel engines.

ORNL’s approach to the the challenge of methanol ignition in diesel engines pairs methanol with a small amount of diesel used as a pilot fuel to start combustion, enabling methanol dual fuel operation across a much wider range of conditions.

“This system allows marine engines to use more than 75% methanol under a wide range of power levels and without reducing performance,” said ORNL’s Derek Splitter, project lead for the Cooperative Research and Development Agreement with Caterpillar announced in December 2023.

Although deployment would require engine updates, the method avoids a full redesign and allows the engine to operate on either diesel or dual-fuel methanol.