The U.S. Department of Energy’s Oak Ridge National Laboratory (ORNL) and Caterpillar Inc. have entered into a cooperative research and development agreement to investigate marine methanol-fueled four-stroke engines.
Methanol has been regarded as a fuel for large, two-stroke powered oceangoing vessels, but the availability of methanol-fueled four-strokes could be an attractive option across a broad range of vessel types, according to Caterpillar.
Officials at the Tennessee-based ORNL, which has categorized the marine industry as a “hard-to-electrify transportation sector,” said that methanol “is an attractive fuel alternative to diesel as it reduces carbon emissions, as well as nitrogen oxides and sulfur oxides.”
In addition, its relatively high energy density makes it easier to store on marine vessels than gaseous fuels, meaning it can be more easily integrated into overall existing engine design and operation.
Under the terms of the agreement, the laboratory’s researchers will work with Caterpillar over the next few years “to identify, develop, and test hardware configurations and operating strategies to maximize use of methanol in retrofitted engines.”
Research will be conducted on a Caterpillar in-line six-cylinder four-stroke marine engine that has been modified for methanol use and installed at DOE’s National Transportation Research Center at the ORNL.
New methanol-fueled four-stroke engine designs will also be considered, and several engine combustion strategies will be explored, including dual-fuel, dimethyl ether reforming, and spark-ignited prechambers.
Caterpillar will support ORNL by providing additional materials and research expertise to enable engine performance, efficiency and durability while reducing greenhouse gas (GHG), and other emissions, according to Jim Szybist, ORNL’s section head for propulsion science. “We look forward to working with Caterpillar to develop near-term combustion strategies that can be retrofitted on existing engines to realize immediate reductions in carbon emissions,”
“We also will develop long-term combustion strategies for new engine technologies that achieve 100 percent displacement of diesel fuel with methanol,” he said. “The research we conduct over the next few years will be a significant contributor to decarbonization efforts globally.”
The DOE maintains a Vehicle Technologies Office that focuses on reducing GHG emissions from vehicles including marine vessels. These sectors are significantly more challenging to decarbonize than on-road, light-duty transportation applications and require unique solutions,” Szybist said.
Caterpillar “is proud to be working with ORNL as we develop the technology for a lower carbon future,” said Brad Johnson, vice president of Caterpillar Marine.
“Our marine customers across the U.S. have been clear that methanol will play a key role in their journey to net-zero emissions,” he added.