Biofuels Defined

What Is a Biofuel?
A biofuel is a transportation fuel derived from renewable resources such as plant biomass or municipal wastes that replaces or reduces the quantity of fossil fuel present in the U.S. transportation fuel mix.

The EPA’s Renewable Fuel Standard requirement for 2009 calls for 11.1 billion gallons (10.21 percent of U.S. transportation fuels), which includes 0.5 billion gallons of renewable biodiesel, to be used in the United States. Currently, the U.S. biofuel supply relies largely on ethanol produced from Midwest corn. Other biofuels that play a smaller role include sugarcane ethanol imported from Brazil, biodiesel from U.S. soybeans, and ethanol from U.S. sorghum.

Biofuels can be made from cellulosic biomass – plant matter composed primarily of inedible cellulose fibers that form the stems and branches of most plants. Crop residues (such as corn stalks, wheat straw and rice straw), wood waste, and even municipal solid waste are potential sources of cellulosic biomass. Dedicated energy crops, such as switchgrass or fast-growing trees, are also promising cellulose sources because they can be sustainably produced in many regions of the United States.

The Energy Independence and Security Act of 2007 categorized biofuels and conventional, advanced, and cellulosic:

The term “conventional biofuel” means renewable fuel that is ethanol derived from corn starch.

“Advanced biofuel” means renewable fuel, other than ethanol derived from corn starch, that has lifecycle greenhouse gas emissions that are at least 50 percent less than baseline lifecycle greenhouse gas emissions.

“Cellulosic biofuel” means renewable fuel derived from any cellulose, hemicellulose, or lignin that is derived from renewable biomass and that has lifecycle greenhouse gas emissions that are at least 60 percent
less than the baseline lifecycle greenhouse gas emissions.

Who Is Producing Cellulosic Biofuel Today?

Selected International Biorefinery Projects
The following projects represent a range of technologies and processes being deployed throughout the world, all defined as cellulosic biofuels.

Company	Plant Location	Feedstock	Technology	Capacity (gallons/year)
Abengoa	Hugoton, Kan.	corn stover, wheat straw, milo (sorghum) stubble, switchgrass, and others	thermochemical and biochemical processing	11.4 million
Abengoa	York, Neb.	corn stover, residual starch	enzymatic hydrolysis (Chrysosporium lucknowense), integrated with dry mill corn production	0.47 million (0.02 million from corn stover)
Abengoa	Salamanca, Spain	wheat straw, cereal	steam pretreatment, enzymatic hydrolysis	1.3 million
BioEthanol Japan	Osaka, Japan	wood construction waste	enzymatic hydrolysis, fermentation (Klebsiella oxytoca and E. coli)	0.37 million
BlueFire Ethanol	Lancaster, Calif.	green waste	acid hydrolysis, fermentation	3.1 million
China Resources Alcohol Corporation	ZhaoDong City, Heilongjiang Province	corn stover	steam pretreatment, enzymatic hydrolysis	1.7 million
Iogen	Ottawa, Canada	wheat, oat and barley straw	enzymatic hydrolysis (Trichoderma reesei, Saccharomyces	0.79 million
KL Process Design	Upton, Wyo.	Ponderosa pine wood chips, waste	CO2 pretreatment, enzymatic hydrolysis	1 million
Lignol	Vancouver, Canada	softwood and hardwood	pulping liquor pretreatment, enzymatic hydrolysis	1.3 million
Mascoma	Lansing, Mich.	wood, forestry residues	enzymatic hydrolysis and fermentation (Thermoanaero-bacterium saccharolyticum)	40 million
Poet	Emmetsburg, Iowa	corn fiber, corn stover	enzymatic hydrolysis, integrated with dry mill	30 million
Range Fuels	Soperton, Ga.	timber and forest residue	pyrolysis and catalytic conversion	40 million
Verenium	Jennings, La.	sugarcane bagasse and specially bred energy cane	enzymatic hydrolysis, fermentation (Klebsiella oxytoca and E. coli)	1.4 million
Vivergo (BP, British Sugar, Dupont)	Saltend, Hull, England	wheat not suitable for human consumption	enzymatic hydrolysis, fermentation	110 million