Cellulosic EthanolCellulosic Ethanol

In-Chul HwangIn-Chul Hwang

What is Cellulosic Ethanol?What is Cellulosic Ethanol?

Ethanol made from cellulosic biomass whichEthanol made from cellulosic biomass which

comprises the stems and branches of most plantcomprises the stems and branches of most plantss

Feedstock of cellulosic ethanol is variousFeedstock of cellulosic ethanol is various

- Crop residues: corn stalks, wheat straw- Crop residues: corn stalks, wheat straw

- Wood waste: wood chip- Wood waste: wood chip

- Municipal solid waste- Municipal solid waste

- Dedicated energy crops: switchgrass, poplar - Dedicated energy crops: switchgrass, poplar

Why Cellulosic Ethanol?(1)Why Cellulosic Ethanol?(1) Conventional ethanol has food vs. fuel problemConventional ethanol has food vs. fuel problem - Its main feedstock is also used for food- Its main feedstock is also used for food - Increasing crop ethanol production is competing - Increasing crop ethanol production is competing

for land with food productionfor land with food production - Some argue that ethanol can worsen world food - Some argue that ethanol can worsen world food

shortage and raise food price shortage and raise food price - Crop ethanol can improve energy security but - Crop ethanol can improve energy security but

worsen food securityworsen food security It has limit in large-scale productionIt has limit in large-scale production - US corn ethanol production is likely to top out - US corn ethanol production is likely to top out

around 12 billion gallons a yeararound 12 billion gallons a year

Why Cellulosic Ethanol?(2)Why Cellulosic Ethanol?(2) It can solve this food vs. fuel controversyIt can solve this food vs. fuel controversy - Its feedstock (switchgrass, poplar) is not edible- Its feedstock (switchgrass, poplar) is not edible - It can grow on marginal lands. It will not divert la- It can grow on marginal lands. It will not divert la

nd from food production to its productionnd from food production to its production It has a wide range of feedstock It has a wide range of feedstock - It can replace fossil fuel in significant scale. 30% - It can replace fossil fuel in significant scale. 30%

of US transportation fuel can be supplied by cellof US transportation fuel can be supplied by cellulosic ethanolulosic ethanol

It has higher yield/acre without land limitIt has higher yield/acre without land limit - It can be used as a whole unlike crop ethanol- It can be used as a whole unlike crop ethanol - It doesn’t need specific climate or land so that it - It doesn’t need specific climate or land so that it

can be produced in every region of the UScan be produced in every region of the US It has better GHG reduction potential It has better GHG reduction potential

Production Process (1)Production Process (1) Currently “Hydrolysis” process is dominantCurrently “Hydrolysis” process is dominant1.Pretreatment: make biomass amenable to hydrol1.Pretreatment: make biomass amenable to hydrol

ysis. Hemicellulose and/or lignin is removed and ysis. Hemicellulose and/or lignin is removed and cellulose structure is modifiedcellulose structure is modified

2.Hydrolysis: break down the cellulose into glucos2.Hydrolysis: break down the cellulose into glucose sugars by adding enzyme e sugars by adding enzyme

3.Separation: separate sugar solution from the resi3.Separation: separate sugar solution from the residual lignindual lignin

4.Fermentation: ferment the sugar solution by addi4.Fermentation: ferment the sugar solution by adding bacteria/yeastng bacteria/yeast

5.Distillation: distill beer (mixture of ethanol, cell m5.Distillation: distill beer (mixture of ethanol, cell mass, water) to produce pure ethanolass, water) to produce pure ethanol

Production Process (2)Production Process (2)

Source: Biotechnology Industry Organization, 2007Source: Biotechnology Industry Organization, 2007

Production CostProduction Cost

Source: IEA, 2004Source: IEA, 2004

Currently cost of cellulosic ethanol is far higher than thosCurrently cost of cellulosic ethanol is far higher than those of gasoline and corn ethanole of gasoline and corn ethanol

The higher cost is due to higher capital cost and operatinThe higher cost is due to higher capital cost and operating cost. Feedstock cost is comparatively lowg cost. Feedstock cost is comparatively low

If the constructions of several large-scale commercial plaIf the constructions of several large-scale commercial plants are completed in years, the production cost will decrnts are completed in years, the production cost will decrease.ease.

Current Status-TechnologyCurrent Status-Technology

Production cost has constantly declined oProduction cost has constantly declined over the past five years with improvement in ver the past five years with improvement in biotechnologybiotechnology

Developing cost-effective enzymes will be Developing cost-effective enzymes will be a key breakthrough to commercialization. a key breakthrough to commercialization.

In 2004, Iogen Corporation announced it bIn 2004, Iogen Corporation announced it began the commercial production of cellulosegan the commercial production of cellulosic ethanol.ic ethanol.

Legislation and PolicyLegislation and Policy Energy Policy Act of 2005Energy Policy Act of 2005 - RFS: requires 250 million gallons of cellulosic - RFS: requires 250 million gallons of cellulosic ethanol beginning in 2013ethanol beginning in 2013 - Biorefinery loan guarantee: $250 million/facility- Biorefinery loan guarantee: $250 million/facility for the construction of demonstration plant for the construction of demonstration plant - Biorefinery grant: $650 million for the- Biorefinery grant: $650 million for the commercial production of cellulosic ethanolcommercial production of cellulosic ethanol 2006 Advanced Energy Initiative includes resear2006 Advanced Energy Initiative includes resear

ch funding to produce cellulosic ethanol at compch funding to produce cellulosic ethanol at competitive cost by 2012 etitive cost by 2012

In 2007, 6 commercial-scale cellulosic ethanol plIn 2007, 6 commercial-scale cellulosic ethanol plants were selected for $385 million grant.ants were selected for $385 million grant.

Future ProspectFuture Prospect

EIA predicts ethanol consumption will reach 11 billEIA predicts ethanol consumption will reach 11 billion gallons by 2012, far above 7.5 billions gallons ion gallons by 2012, far above 7.5 billions gallons required by Energy Policy Act of 2005.required by Energy Policy Act of 2005.

Oil Price is expected to keep risingOil Price is expected to keep rising

- Now crude oil is nearing $100/bbl- Now crude oil is nearing $100/bbl 2007 energy bill requires 36 billion gallons of biof2007 energy bill requires 36 billion gallons of biof

uels by 2022.uels by 2022.

- It mandates annual increases of 3 billion gallons - It mandates annual increases of 3 billion gallons

in the use of advanced biofuelsin the use of advanced biofuels

ConclusionsConclusions Current ethanol boom caused by strong support poCurrent ethanol boom caused by strong support po

licy, high oil price will eventually lead to cellulosic elicy, high oil price will eventually lead to cellulosic ethanol on the marketthanol on the market

Mandatory flex-fuel requirement for new vehicles aMandatory flex-fuel requirement for new vehicles and nation-wide ethanol pump stations are needed fnd nation-wide ethanol pump stations are needed for large-scale use of cellulosic ethanolor large-scale use of cellulosic ethanol

Cellulosic ethanol will have synergy effect if combiCellulosic ethanol will have synergy effect if combined with PHEV ned with PHEV

- If all ground vehicles were suddenly flex-fuel PHE- If all ground vehicles were suddenly flex-fuel PHEVV→→ they can replace 97% of current ground transp they can replace 97% of current ground transportationortation

ReferencesReferences1.1. IEA, 2004, “Biofuels for Transport: An International Perspective”IEA, 2004, “Biofuels for Transport: An International Perspective”

ttp://www.iea.org/textbase/nppdf/free/2004/biofuels2004.pdfttp://www.iea.org/textbase/nppdf/free/2004/biofuels2004.pdf2.2. Science vol. 315,16 March 2007Science vol. 315,16 March 2007

“Biofuel researchers prepare to reap a new harvest”“Biofuel researchers prepare to reap a new harvest”3.3. http://www.doe.gov/print/4827.htmhttp://www.doe.gov/print/4827.htm4.4. RFA, 2006, “ From niche to nation: ethanol industry outlook 2006”RFA, 2006, “ From niche to nation: ethanol industry outlook 2006”

http://www.ethanolrfa.org/objects/pdf/outlook/outlook_2006.pdfhttp://www.ethanolrfa.org/objects/pdf/outlook/outlook_2006.pdf5.5. DOE press release, February 28, 2007 http://www.doe.gov/print/4827.DOE press release, February 28, 2007 http://www.doe.gov/print/4827.

htmhtm6.6. Biomass & Bioenergy 28 (2005) 384-410Biomass & Bioenergy 28 (2005) 384-410

“Ethanol from lignocellulosic biomass: techno-economic performance “Ethanol from lignocellulosic biomass: techno-economic performance in short-, middle- and long-term”in short-, middle- and long-term”

7.7. Biotechnology Industry Organization, 2007Biotechnology Industry Organization, 2007“Industrial biotechnology is revolutionizing the production of ethanol tr“Industrial biotechnology is revolutionizing the production of ethanol transportation fuel ansportation fuel http://www.bio.org/ind/biofuel/CellulosicEthanolIssueBrief.pdfhttp://www.bio.org/ind/biofuel/CellulosicEthanolIssueBrief.pdf

8.8. Ron Gremban, 2006, “PHEVs: the Technical Side “Ron Gremban, 2006, “PHEVs: the Technical Side “ www.calcars.org/calcars-technical-notes.pdf www.calcars.org/calcars-technical-notes.pdf