Thursday, May 29, 2008
Coskata Joined in Race for Cellulosic Ethanol
Although Coskata may be getting the most amount of press and attention these days for their work towards mass producing cellulosic ethanol, they definitely are not the only ones working on the problem. Louisiana based Verenium Corporation has announced plans to enter the cellulosic ethanol race with a pilot-scale plant of their own in Jennings, Louisiana. The company plans to have a scaled up commercial plant capable of producing 30 million gallons of ethanol per year by 2010, which would put it approximately on schedule with Coskata.
However, there are some major differences that give Verenium the advantage in terms of hurrying production along and disadvantages. Verenium produces cellulosic derived ethanol using an enzyme pretreatment and then genetically engineered e. coli stains that possess the genes to convert 5-carbon sugars, such as xylose, into ethanol. This is an improvement over yeast, which are only able to convert 6-carbon sugars, such as glucose, into ethanol. With the e. coli stain possessing an additional pathway that is abundant in cellulosic ethanol, it allows the plant to move forward quickly with relatively novice technology. In other words, existing corn-ethanol plants could easily be retrofitted with this new bacteria and would become cellulosic ethanol plants. However, the downside is that the technology does not escape many of the problems that currently plague corn-based ethanol. Sure, the feedstock would be more flexible, owing to the company's claim that they will be able to produce ethanol forl around $1.84 per gallon including their debt responsibilities. But they don't escape the massive amounts of energy needed in the pretreatment step, which Coskata gets around by gasifying the biomass, and it doesn't seem as though Verenium has improved any of the downstream applications, such as separation of ethanol and water after the fermentation step.
The bottom line is that Verenium is going to be a fast mover towards cellulosic ethanol, much like South Dakota based Poet. However, in the long run, Coskata will have a definite advantage over these two players as its holistic approach towards cellulosic ethanol production that seeks to address many if not all of the problems found in corn-based ethanol, will eventually prove to be the winner.
Below are graphics provided by Verenium on their process stream and on their calculated costs to produce a gallon of ethanol.