In the United States (US), the Department of Energy’s (DOE's) Oak Ridge National Laboratory (ORNL) and Caterpillar Inc. have entered into a Cooperative Research and Development Agreement, or CRADA, to investigate using methanol as an alternative fuel source for four-stroke internal combustion marine engines. The collaboration supports efforts to decarbonize the marine industry, a hard-to-electrify transportation sector.
As the United States continues to seek ways to reduce environmentally harmful greenhouse gas (GHG) emissions, methanol is an attractive fuel alternative to diesel because it reduces carbon emissions.
Methanol also reduces emissions of nitrogen oxides (NOx) and sulfur oxides (SOx). In addition, methanol’s 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.
Maximize the use of methanol
Although methanol has many advantages, it is more difficult to ignite than diesel. Under the terms of the CRADA, ORNL researchers will work with Caterpillar over the next few years to identify, develop, and test hardware configurations and operating strategies required to maximize the use of methanol in engines retrofitted for methanol.
Research will be conducted on Caterpillar’s in-line 6-cylinder marine engine that has been modified for methanol use and installed at DOE’s National Transportation Research Center at ORNL.
New engine designs will also be considered, and several engine combustion strategies will be explored including dual-fuel, dimethyl ether (DME) 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 GHG and other emissions.
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. The research we conduct over the next few years will be a significant contributor to decarbonization efforts globally, said ORNL’s Jim Szybist, section head for Propulsion Science.
The project supports DOE’s Vehicle Technologies Office’s (VTO) focus on reducing GHG emissions from off-road vehicles such as railway, aviation, and heavy-duty vehicles used in agriculture, construction, mining, and marine vessels.
These sectors are significantly more challenging to decarbonize than on-road, light-duty transportation applications and require unique solutions.
Caterpillar is proud to be working with ORNL as we develop the technology for a lower carbon future. Our marine customers across the United States have been clear that methanol will play a key role in their journey to net-zero emissions. The maritime industry has unique challenges that can’t necessarily be met by technologies being developed for other transportation sectors, so it is important to have this collaboration with ORNL to accelerate the technology and set the path for the future, said Brad Johnson, VP of Caterpillar Marine.
In addition to DOE’s Vehicle Technologies Office, the collaboration is funded by the US Department of Transportation Maritime Administration.
