Switchgrass is on the forefront of biomass technology and it could be converted into jet fuel to power Navy planes and more.
The National Renewable Energy Laboratory (NREL), run by the Energy Department, is looking into ways that switchgrass could be used to fuel jets. To achieve this goal, the group has partnered with the U.S. Navy, Cobalt Technologies, and the Show Me Energy Cooperative.
Producing jet fuel from biomass like switchgrass is not new. However, before jets start flying on fuel made from the grass, production would have to be both affordable and available in quantities large enough to make economic sense.
"This can be an important step in the efforts to continue to displace petroleum by using biomass resources. We're converting biomass into sugars for subsequent conversion to butanol and then to JP5 jet fuel," Dan Schell, NREL manager for bioprocess integration research and development, said.
The Department of Energy is funding four separate projects to find a renewable source of biomass that could be turned into fuel to power both land vehicles and airplanes.
Switchgrass is a wild grass that grows in all latitudes of the United States and Mexico, but is found primarily in the prairies. If this wild grass could be successfully used for the production of jet fuel in the large-enough quantities, it would provide a green alternative to fossil fuels, and would not require the use of a food stock like corn. Producing jet fuel from switchgrass would produce 95 percent less greenhouse gases than refining fossil fuels.
The grass is collected by the Show Me Energy Cooperative, and then converted into sugars at the NREL through the use of enzymes, after pre-treating with a weak acid. The sugars are then fed into fermenters built by Cobalt Technologies with a capacity of nearly 2,400 gallons. There, they are converted into butyl alcohol (butanol) through the action of microorganisms. Using Navy know-how and catalysts, the alcohol is converted into jet fuel back at NREL.
Switchgrass grows throughout Kentucky, where it is also being studied for use as an alternative fuel, if only as biomass to be directly burned. There, researchers from the University of Kentucky College of Agriculture have had some success in using the grass to produce green energy.
"We learned a whole lot and found some useful applications for the forage until a consistent biomass market develops," Ray Smith, University of Kentucky extension forage specialist, said. Interest in the grass from the Navy could be the market for which Smith is looking.
If tests are successful, the Departments of Defense and Agriculture will assist companies who wish to produce the greener fuel.
