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National Renewable Energy Laboratory5013 Denver West Parkway, Golden, CO 8040103-275-3000 www.nrel.gov

NREL is a na onal laboratory of the U.S.Department of Energy, O ce of Energy

ciency and Renewable Energy, operatedy the Alliance for Sustainable Energy, LLC.

REL/FS-6A42-60663 November 2013

REL prints on paper that c ontains recycled content.

NREL Proves Cellulosic Ethanol Can Be Cost Compe ve

Ethanol from non-food sourcesknown as cellulosic ethanolis a near-perfecttransporta on fuel: it is clean, domes c, abundant, and renewable, and it can poten

ally replace 30% of the petroleum consumed in the United States, but its rela velyhigh cost has limited its market. That changed in 2012, when the Na onal RenewableEnergy Laboratory (NREL) demonstrated the technical advances needed to producecellulosic ethanol at a minimum ethanol selling price of $2.15/gallon (in 2007 dollars).Through a mul -year research project involving private industry, NREL has proventhat cellulosic ethanol can be cost compe ve with other transporta on fuels.

A er several years of modeling, performing biomass-to-fuels conversion testruns, and compiling and analyzing market data, NREL was able to demonstrate actualscenarios to meet the cost goal, which was established by the U.S. Department ofEnergy (DOE) in 2006. NREL met the cost goals using both biochemical and thermochemical processes.

The biochemical process used a dilute-acid pretreatment of corn stover (stalks,leaves, and cobs) and then employed enzymes to release the sugars from the pre -treated stover. The mix of sugars were then fermented together to produce ethanolat a minimum ethanol selling price of $2.15/gallon.

The thermochemical pla orm focused on indirect gasi ca onusing high temperatures to convert woody biomass into a methane-rich gas called syngas, then em -ploying a catalyst to convert the syngas into mixed alcohols, including ethanol. NRELdemonstrated an indirect gasi ca on scenario with a minimum ethanol selling priceof $2.05/gallon.

The models developed by NREL have enabled private industry to ramp up e orts tocommercialize cellulosic ethanol produc on. Facili es to produce cellulosic ethanol

are under construc on across the country, including DOE-supported projectsled by Abengoa in Hugoton, Kansas;POET in Emmetsburg, Iowa; and INEOin Vero Beach, Florida.

Industry and DOE are also leveragingthe research to commercialize othertechnologies for biomass conversion, including conver ng cellulosic feedstock

into drop-in biofuels that are compatible with exis ng infrastructure andnearly indis nguishable from gasoline,diesel, and jet fuel.

NRELs Thermochemical Pilot Plant was used todevelop and demonstrate the technologies tomeet DOEs cost goals. Among the equipmentin the pilot plant i s the recircula ngregenera ng reformer, which providescon nuous reforming of syngas andcon nuous regenera on of the catalyst.Photo by Dennis Schroeder, NREL 25486

Quick FactsNREL and its industry partners usedthermochemical and biochemical processmodeling and techno-economic andlife-cycle analysis to demonstrate scenar -ios to meet the $2.15/gallon cost goal forcellulosic ethanol......................................................................

Signi cant improvements in pretreat -ment, enzyma c hydrolysis, and fermen -ta on helped meet the cost goals forbiochemical conversion, while advancesin methane and tar reforming and fuelsynthesis helped meet the cost goalsfor thermochemical conversion......................................................................

From 2002 to 2012, the modeled cost ofcellulosic ethanol produc on decreasedfrom $9.00/gallon to $2.15/gallon......................................................................

Scien sts led pilot-scale projects at NRELsIntegrated Biore nery Research Facilityand Thermochemical Users Facility tovalidate the modeled produc on costs......................................................................

The work done to meet the cellulosicethanol cost goal is also being used toadvance drop-in biofuels. For example,biomass-to-sugar and syngas conversiontechnologies are applicable to the produc -

on of drop-in biofuels. In addi on, thecomposi onal analysis techniquesare similar between cellulosic ethanoland drop-in biofuels, and pilot- andbench-scale equipment for cellulosicethanol is easily repurposed for drop-inbiofuel produc on.

INNOVATION IMPACT Bioenergy

For more NREL innova ons, visit www.nrel.gov/innovaton/

http://www.nrel.gov/http://www.nrel.gov/innovation/http://www.nrel.gov/innovation/http://www.nrel.gov/