EBI, September 24, 2010
(EPA, 2010)
(EIA, 2010)
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Similarities to current energy system
Near-term
Cost effective
Scalable
Deployable/storable
Carbon-negative potential
Rural economic development
Appropriate technology options for the
developing world
Synergies with fossil fuels
Synergies with other renewables
Perhaps better to ask “How?”
1.
2.
3.
Air Quality
Short-Lived Climate Forcers
Land-Use Efficiency
Ozone increase in LA and northeast offset by
decrease in southeast
 E85 unlikely to improve air quality
 Emissions outside of vehicle phase neglected
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(Jacobson, ES&T, 2007)
(Hill et al., PNAS, 2007)
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Human health costs ~ Climate change costs
Importance of upstream emissions relative to
vehicle emissions
Life-cycle Emission
(g emitted / mmBtu fuel)
900
800
Sugarcane Ethanol
700
Corn Ethanol
600
500
400
300
200
100
0
NOx
VOC
SOx
CO
Emission Factor (g emitted/ mmBtu)
7000
3000
Straw Field Burning
Straw Field Burning (50% Area Burned)
Other Farming
Ethanol Refinery
Ethanol T/D
Vehicle Use
2000
1000
0
VOC
NOx
PM10
PM2.5
SOx
CO
1.
2.
Create a market for sugarcane trash
Emissions from indirect land-use change
(Morton et al., GCB, 2008)
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Aerosols and Ozone
Atmospheric lifetimes of days to weeks
Cooling and warming properties
Spatial-explicit climate impacts
Black Carbon has 55% of the RF caused by
CO2 and a greater forcing than all other
SLCFs (Ramanathan and Carmichael, 2008)
(Unger et al., PNAS, 2008)
Climate Forcing (g CO2-e / MJ fuel)
100
90
80
70
60
50
40
30
20
10
0
Gasoline
Sugarcane
Sugarcane +
BC_low
Sugarcane +
BC_high
(Naik et al., GRL, 2007)
(Campbell et al., ES&T, 2008)
19
Abandoned Areas (1000 km2)
1,200
1,000
800
County crop
600
HYDE crop high
HYDE crop low
400
SAGE crop
HYDE pasture high
200
HYDE pasture low
0
(Campbell et al., in prep)
20
(Debolt, Campbell, et al.,
GCB-Bioenergy, 2010)
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Source for stratospheric sulfate aerosol.
Important role in stratospheric ozone.
A novel tracer of terrestrial photosynthesis?
CO2
COS
(Campbell et al., Science, 2008)
30,000
20
20,000
10
10,000
0
0
Net Output
30
Vehicle Cycle Ga soline Input
40,000
Vehicle Cycle Electric Input
40
Fuel Cycle Gasoline Input
50,000
Fuel Cycle Electric Input
50
Gross Electricity Output
Net Output
Vehicle Cycle Ga soline Input
Vehicle Cycle Electric Input
Fuel Cycle Gasoline Input
Fuel Cycle Electric Input
Gross Ethanol Output
Transportation Mileage (10 3 mi ha -1 y -1 )
a) Ethanol
b) Bioelectricity
(Campbell, Lobell, & Field, Science, 2009)
25
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Advantages to expanding focus to include
electricity in addition to liquid fuels
Greater emphasis on jet and tanker fuels
Lignin rich feedstock
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Win-win solutions where environmental
mitigation results in more bioenergy supply?
 E.g. Sugarcane burning vs. second-generation
fuels
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SLCFs incorporated in mandated GHG
thresholds?
International leakage of air quality impacts?
Abandoned lands and other alternative land
resources?