GM, Coskata join forces to correct misconceptions about ethanol

By Holly Jessen | March 31, 2011

With four decades of experience backing him up, Rathin Datta, chief scientific officer for Coskata Inc. has identified the primary renewable liquid fuel. “There’s no doubt—no technical, thermodynamic or energy or any other doubt—that ethanol is the molecule,” he told EPM.

Datta is one of four authors of a perspective paper recently published in the Journal of Chemical Technology & Biotechnology. The paper singles out ethanol as the most efficient and productive use of biomass. Co-authors include Mark Maher, executive director, powertrain/vehicle integration, General Motors Inc.; Coleman Jones, GM biofuels implementation manager; and Richard Brinker, dean and professor of forestry and wildlife sciences, Auburn University.

The goal, said Wes Bolsen, chief marketing officer and vice president of government affairs for Coskata, is to help people understand ethanol’s potential. “This paper really says, ‘Look, ethanol can be the primary renewable fuel,’” he said. “‘This isn’t something that is an accident or something that we created because we had a bunch of corn.’”

First, biomass-to-ethanol conversion enjoys natural efficiencies leading to the highest yields. The fuel also has a long history of superior performance and is ready for use in more than 80 percent of today’s vehicles. Finally, biomass is abundant enough to displace foreign oil. The paper pointed to studies by the USDA, U.S. DOE and major national laboratories that projected that large and sustainable biomass supplies will be available to produce nearly 90 billion gallons yearly in the U.S.

Datta and Maher cooked up the idea of writing a perspective paper to correct some of the misconceptions about ethanol during a visit last year to the company’s cellulosic ethanol facility in Madison, Pa. Besides being very supporting of the ethanol industry overall, GM is a past investor in Coskata. Brinker was brought on board due to his experience and understanding of biomass use in the Southeast, Datta said.

To Datta, the most important point of the paper is that, based on the laws of thermodynamics and photosynthesis, high-yield biomass feedstocks are highly oxygenated. The second most important piece of information follows right behind that—highly oxygenated components get the highest yields and are the best molecule to run internal combustion engines. “For liquid fuel or chemical feedstock production from this feedstock, the winning strategy is to produce a product that has proven and widespread use, with the highest yield using the entire feedstock— and that is ethanol,” the paper said.

The perspective paper also dug into the two main pathways for producing ethanol from biomass: the biochemical and thermochemical approaches. A third path—a hybrid approach, in which gasification is used to convert biomass to syngas, microorganisms ferment the syngas into ethanol and the ethanol is then separated from water—has long been considered superior, the perspective paper said. However, most research and development has focused in on either biochemical or thermochemical conversion of ethanol. Three companies, Coskata, Ineos Bio and LanzaTech, have been working on the hybrid approach. “Now we are in the throes of getting this to commercial readiness,” Datta said.