NREL, Chevron consider renewable diesel research
In the five-year agreement, both companies will research and develop new production technologies for biofuels, including renewable diesel. However, Chevron and NREL weren't limiting the project to this area. "They still have to sort out where the research is going to head," Douglas said.
Right now, the focus is less on the biofuel end-product and more on the best feedstock for the job. Ultimately, the real target of the research is finding the best way to convert a cellulosic feedstock into a usable fuel, "whatever that fuel might be," Douglas said.
Chevron and NREL don't plan to pursue biodiesel production technology through this project, at least not biodiesel made from feedstocks such as soybeans. "They're not looking at making biodiesel in the conventional sense," he said.
The research may delve into producing renewable diesel from bio-oils. Bio-oils can also be used to produce hydrogen, he said.
"We believe that for the next generation of biodiesel production to become commercially viable, there must be flexibility to diversify the feedstocks, and the process by which the biofuels are produced must also increase in efficiency and effectiveness," said Rick Zalesky, vice president of biofuels and hydrogen for Chevron Technology Ventures. "This research will address both of these fundamental challenges."
Chevron and NREL each have other research partnerships in the area of cellulosic biofuels. In the past year, Chevron also announced research alliances with the University of California, Davis, and the Georgia Institute of Technology. At about the same time Chevron partnered with NREL, NREL was linked with investment company HamiltonClark for work on cellulosic ethanol.
What Is Renewable Diesel?
According to the U.S. EPA, renewable diesel is defined as a nonester renewable fuel. Biodiesel is made from mono-alkyl esters.
Nonester renewable diesel is derived from nonpetroleum renewable resources, including-but not limited to-poultry fats and poultry wastes, municipal solid waste, sludge and oils derived from wastewater, and other wastes, according to the EPA. Current examples include diesel fuel produced from fats and oils through a refinery hydro-heating process.
The EPA plans to finalize a proposed ruling for equivalency values for renewable fuels, including renewable diesel, by early 2007, according to Enesta Jones, an EPA spokeswoman. The values will be used to track renewable fuels standard (RFS) credits that were initiated in the Energy Policy Act of 2005. In the meantime, the EPA has proposed that biodiesel has an equivalency value of 1.5 gallons, while nonester renewable diesel has a 1.7 equivalency value. "Equivalence values of nonethanol renewable fuels are based on their energy values in comparison with ethanol, and then adjusted as necessary for their renewable component content," Jones told Biodiesel Magazine.