Transcript Slide 1

Institute of Transportation Studies
University of California, Davis
Future of Corn Ethanol
Yellow is green?
UC Davis Book Project
Daniel Sperling
Professor and Director
November 6, 2006
Michael Pollan expressed concerns about
the industrialization of corn. He expressed
skepticism about its use for ethanol, but
did not pursue the question very deeply.
My goal:
1) What is the status of corn ethanol.
2) What are the pros and cons of using corn
to make ethanol?
General Motors Print Ads (early 2006)
Every US presidential candidate as far back as I can
remember has endorsed corn ethanol.
President Bush’s 2006 State of the Union
America is addicted to oil … The best way to break
this addiction is through technology ... We must
… change how we power our automobiles ...
We'll also fund additional research in cuttingedge methods of producing ethanol, not just from
corn, but from wood chips and stalks, or switch
grass. (Applause.)
7.5 billion
gallons
mandated
for 2012
,
Earth-Policy.org
Of the 11.8 Billion Bushels of Corn Produced in U.S. in 2004,
~12% Was Used for Ethanol Production (~16% in 2006)
U.S. Corn Usage by Segment 2004
Feed/Residual: 56.4%
Export: 18.5%
Ethanol: 11.7%
High Fructose Corn Syrup: 5.2%
Starch: 2.7%
Sweeteners: 2.2%
Cereal/Other: 1.8%
Beverage/Industrial Alcohol: 1.3%
Seed: 0.2%
Source: ERS/USDA, 2004, Feed Outlook (in RFA, 2005); EIA
Economics of Corn Ethanol Based on Using
Protein in Kernel as Animal Feed (co-product)
Protein
Carbon Dioxide
Ethanol
Distillers Dry
Grains and
Solubles (DDGS)
Starch
(Animal feed mostly for
cattle that contributes
revenue of ~$0.60 per
gasoline-gallon-equivalent – but transport cost is very
expensive, and thus quickly
saturates nearby feedlot
and dairy farm markets.)
Reasons for Ethanol’s Success in US
• High oil prices
• High octane (to enhance gasoline)
• Strong political support in farm states
 Rules requiring oil companies to use ethanol and to
“oxygenate” the gasoline
 Corn lobby was able to overcome opposition from oil
companies and California!
• Recent rejection of MTBE as acceptable
oxygenate additive (leaving only ethanol)
• Large subsidies
Substantial Biofuel Subsidies in Place in US
Ethanol
Federal
• $0.51/gallon
• Various direct and indirect subsidies (small biofuel
producers, new ag fuel businesses, biofuel crop
production)
• Brazilian import tariffs
State
• 22 states provide production incentives
• 32 states provide use incentives
Does Corn
Ethanol
Save Oil
and GHGs?
Caution: Energy Balance and GHG Analyses of
Biofuels Sensitive to System Boundary Choices
Operation-Related Activities:
Fertilizer, Farming,
Corn Transportation, Ethanol
Production, Ethanol Transportation,
Energy Use for Producing
Process Fuels
Agriculture yields continue to grow…
Corn Yield (T/ha) 1960 – 2000
Selective breeding to genetic engineering
…and farming continues to increase efficiency…
0.65
?
Bushels/lb. Fertilizer
0.60
U.S. Corn Output Per Pound of Fertilizer
Has Risen by 70% in The Past 35 Years
0.55
Precision
farming, etc.?
0.50
0.45
0.40
0.35
0.30
1965
1970
1975
1980
1985
1990
Based on historical USDA data; results are 3-year moving averages
1995
2000
2005
… and processing technology and efficiency also
continue to improve…
70,000
1980s
60,000
2000s
Btu/Gallon
50,000
40,000
30,000
20,000
10,000
0
Wet Mill
Dry Mill
Source: From DOE/Argonne - discussions with ethanol plant designers, recent
USDA data, and other reported data.
But Even With Many Efficiency Improvements, Corn
Etoh Has Small GHG Benefits
“Our best point estimate for average performance today is that corn
ethanol reduces …GHG emissions only moderately, by about 13%.”
Delucchi’s (2006) latest point estimate is 2%.
Source: Alex Farrell et al, 2006
Corn Ethanol Is Fairly Expensive to Produce
Ethanol Fuel Prices Soared and Are Now Tumbling
Pros and Cons of Corn Ethanol
Pro
• Boosts corn prices and stimulates rural development
• Reduces oil imports
• Easier to implement than battery EVs and hydrogen
• Starts the transition to alternative fuels
Con
• Relatively high cost
• Large land and water requirements
• Land-related environmental impacts (soil erosion, water/chemical
runoff)
• No air quality benefits
• Only minor reduction in GHGs
• Boosts food prices (food vs fuel issue) (grain
required to fill a
25-gallon SUV gas tank with ethanol could feed
one person for a year)
• Limited opportunities in most parts of world (Japan, EU, China)
Many Different Biofuels and Biofuel Feedstocks
Prominent Biofuels Pathways
• Fermentation of sugar/starch materials (ethanol) – what we do now
 Corn in US, with co-product used for animal feed
 Sugar in Brazil, with bagasse used for energy
• Lignicellulose (for ethanol, methanol, petroleum-like liquids, gases)
 Waste from forests, sawmills, etc
 Crop residues (corn stover, rice straw, etc)
 Woody material (wood farms)
 Grasses
• Oils to replace diesel
 Waste oils (frying oil, animal fats)
 Oil seeds and algae (rapeseed provides 7 times greater
yield/acre than corn, and palm oil provides 40 times greater yield).
Many new thermochemical and biological techniques under
development to increase feedstock yields and conversion efficiencies,
Many Different Fuels Can Be Made From Many
Different Forms of Biomass In Many Different Ways
Biological
Conversion5
Feedstock
Sugar &
Starches
(Agricultural
crops)
Conversion Fermentation
of sugars
& Refining
Primary
Energy
Products
Lignocellulosic
(All sources)
Cellulose-tosugars, then
fermentation
Ethanol
Thermochemical
Conversion
Landfill Gas
& Biogas
Lignocellulosic
(All sources,
including coal)
Anaerobic
digestion,
cleaning,
separation
Gasification/
syngas
processing
• Pipeline quality
gas
• CNG
• LNG
• Hydrogen (via
reforming)
• FischerTropsch liquids
• Mixed alcohols1
• DME2
• Ethanol3
• Methanol
• Hydrogen
Pyrolysis,
thermal
depolymerization
& upgrading
Synthetic crude,
Biogasoline,
Biodiesel
Chemical
Conversio
n
Bio-oils
(Waste oils/fats
and oilseed
crops)
Transesterification
Biodiesel
1. Via catalytic synthesis. 2. Dimethylether. 3. Via syngas fermentation. 4. Pyrolysis oils require substantial upgrading before they can be used for
transportation applications (e.g., before they can be processed in a conventional refinery). It is more likely they would undergo more modest upgrading
for use as boiler fuel or in a stationary IC engine or gas turbine. 5. Also includes direct microbial conversion of sunlight to hydrogen.
Much Biomass Available to Make Fuels
ORNL 2005
% of GGE
Used by
Transport
Crop Residues
10-22
5-11%
Grass (Perennial) Crops
0-19
0-10%
Wood/Forest Resources
7-18
4-9%
17-59 BGGE
9-30%
Type of Biomass
Total
(1.1-3.8M b/d)
•
•
•
Source: USDA, USDOE “Billion Ton Vision” Report
“% of GGE” calculation is based on a future 200 billion GGE demand per year (currently 173B)
Criteria: Biomass is accessible by road, sensitive areas excluded, largely ignores economic considerations
and competing uses for biomass (other forms of energy and bio-based products)
Corn Ethanol is not Green, But Does it Set
the Stage for Other (Greener) Biofuels?!
• Conditions drivers for new fuels
• Conditions politicians/regulators for new fuels
But
• If biofuel of the future may not be ethanol, then …
 Introduction of flex fuel cars is wasted (or worse because car
companies get special fuel credits)
 Creation of separate fuel distribution system for ethanol is
“wasted”
What would Michael Pollan say?
What do we say?