General Motors is investing in Coskata, a start-up biofuels company that says it can produce ethanol from a wide range of feedstocks for less than $1.00 per gal, compared with a wholesale selling price of more than $2.00 per gal today. GM will receive the first ethanol from Coskata’s pilot plant in the fourth quarter of 2008. Acccording to Chemical & Engineering News the first commercial-scale plant will be running in 2011, making 50 million to 100 million gal of ethanol (per year).
Coskata’s process is feedstock flexible, and enables the use of cost-effective, locally abundant materials to achieve the lowest ethanol production cost targets in the industry. This groundbreaking approach addresses many of the constraints lodged against current renewable energy options, including environmental, transportation and land use concerns.
Using patented microorganisms and transformative bioreactor designs, Their process can turn virtually any carbon-based feedstock, including biomass, municipal solid waste, bagasse and other agricultural waste into ethanol, making production a possibility in almost any geography. The three steps of the process are:
- Incoming material converted to synthesis gas (gasification)
- Fermentation of synthesis gas into ethanol (bio-fermentation)
- Separation and recovery of ethanol (separations)
During gasification, carbon-based input materials are converted into syngas using well-established gasification technologies. After the chemical bonds are broken using gasification, Coskata's proprietary microorganisms convert the resulting syngas exclusively into ethanol by consuming the carbon monoxide (CO) and hydrogen (H2) in the gas stream. Once the gas-to-liquid conversion process has occurred, the resulting ethanol is recovered from the solution using "pervaporation technology."
Coskata's proprietary microorganisms eliminate the need for costly enzymatic pretreatments, and the bio-fermentation occurs at low pressures and temperatures, reducing operational costs. In addition, the Coskata process has the potential to yield over 100 gallons of ethanol per ton of dry carbonaceous input material, reducing both operational and capital costs.
Together, Coskata's proprietary microorganisms and bioreactor designs lead to the highest conversion rates of feedstock to ethanol in the industry, as well as greater resistance to phage infections and bacterial contaminants.
As syngas fermentation leads to lower ethanol concentrations than corn fermentations, the energy and cost to separate the ethanol from water is proportionally higher. Coskata's exclusively licensed membrane separation technology dramatically improves the separations and recovery component of ethanol production, reducing the required energy by as much as 50%.
Coskata’s process technology is ethanol-specific and enzyme independent, requiring no additional chemicals or pre-treatments; environmentally superior, reducing carbon dioxide emissions by as much as 84% compared to conventional gasoline; and has the ability to generate 7.7 times as much energy as is required to produce the ethanol, compared to corn ethanol which generates approximately 1.3 times as much energy according to Argonne National Labs.
The partnership between the two companies was revealed Sunday, Jan. 13, at the North American International Auto Show in Detroit. Coskata, based in Warrenville, IL, was initially formed with funding from Advanced Technology Ventures (ATV), GreatPoint Ventures and Khosla Ventures.
This post based on materials found on Coskata's website and press releases.