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Stanford UniversityGlobal Climate & Energy Project
Biomass Energy: the Climate Protective Domain
Christopher Fieldwww.global-ecology.org
GCEPCarnegie Institution for Science
Stanford university
July, 2008
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The Need for Technology
•
Concentrations of CO2
will rise above current values (380 ppm), even under the most optimistic scenarios.
•
Stabilization will require that emissions peak and then decline. Peak timing depends on the stabilized concentration.
•
Improvements in efficiency, introduction of renewables, nuclear power, …
all help.
•
New technology will be needed for the really deep reductions.
•
Concentrations of CO2
will rise above current values (380 ppm), even under the most optimistic scenarios.
•
Stabilization will require that emissions peak and then decline. Peak timing depends on the stabilized concentration.
•
Improvements in efficiency, introduction of renewables, nuclear power, …
all help.
•
New technology will be needed for the really deep reductions.
Wigley
et al Nature 1996
3
The Global Climate and Energy Project
Goals•
Fundamental, precommercial
research•
Novel technology options for energy conversion and utilization
•
Impact in the 10-50 year timeframe
Strategy•
Step-out research: revisit the fundamentals and explore new approaches
•
High risk / high reward
Budget •
$225M commitment
Participants•
Industrial sponsors•
Academic institutions -
Stanford and an increasing number of other universities worldwide
GoalsGoals•
Fundamental, precommercial
research•
Novel technology options for energy conversion and utilization
•
Impact in the 10-50 year timeframe
StrategyStrategy•
Step-out research: revisit the fundamentals and explore new approaches
•
High risk / high reward
Budget Budget •
$225M commitment
ParticipantsParticipants•
Industrial sponsors•
Academic institutions -
Stanford and an increasing number of other universities worldwide
4
GCEP Strategies
Energy OptionEnergy Option
ScientificChallenge
ScientificChallenge
Tech
nolo
gy P
rogr
ess
TimePresentTime
Step back to fundamentals
Step back to fundamentals Scientific
Advance to Enable
Development of a Game-
changing Technology in Reduced
Time
Scientific Advance to
Enable Development of a Game-
changing Technology in Reduced
Time
Step-out Idea
Step-out Idea
Pathway to Technical Breakthroughs
Existing Project Areas•
Advanced combustion •
Advanced coal•
Carbon capture and separation •
CO2 sequestration•
Hydrogen production, storage, utilization•
Advanced transportation•
Renewable energies (solar, biomass)•
Advanced materials (separation membranes, catalysts, …)
Areas Undergoing Assessment•
Nuclear technologies (fission and fusion)•
Electric energy distribution and infrastructure
Future Research Areas•
Geo-engineering
Research Portfolio
5
•
$111M funding allocated to GCEP
•
44 full-term research programs
•
11 exploratory research programs
•
69 investigators•
24 institutions •
Over 300 graduate students and post-docs
•
6 patent applications
•
$111M funding allocated to GCEP
•
44 full-term research programs
•
11 exploratory research programs
•
69 investigators•
24 institutions •
Over 300 graduate students and post-docs
•
6 patent applications
Current
Status
Funding Distribution
6
Participating
Institutions
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Bioenergy:
A great green hope or impending disaster?
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A climate-friendly liquid fuel•
Target of immense hype and speculation
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Threat to climate, biodiversity, and rural lifestyles
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How can biofuels
be lower carbon?
•
Photosynthesis–
Light + CO2
plant + O2
•
Plant combustion–
Plant + O2
energy + CO2
•
Net–
Light + CO2
energy + CO2
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The hope
•
Net fossil fuel offset•
Big slice of the future energy system
•
Increased income source for rural areas•
Acceptable environmental implications
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The hype
•
Senate energy bill calls for a 7-fold increase in ethanol production–
36 billion gallons/year by 2022
•
BP funds $500 million biofuels
research program
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US DOE funds 3 biofuels
centers at $125 million each
•
Hot trend in venture capital
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The threat
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Decreased food security•
Decreased water security
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Net warming•
Ocean and freshwater pollution
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Loss of conservation areas•
Loss of biodiversity
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Loss of rural jobs“The end of the ethanol boom is possibly in sight and may already be here,” Neil E. Harl, NY Times, 9/30/07
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GCEP: Using the wheat and the chaff
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Re-engineering photosynthesis•
Re-engineering biofuels
processing
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Re-engineering plants to facilitate biofuels production
•
Finding the climate-protective domain
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Climate-protective biofuels
•
Grow more plants–
Without more environmental downsides
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Get more energy per unit of plant biomass•
Figure out where it does and doesn’t make sense to produce biofuels
1414
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Engineer Synechocystis organism to demonstrate photobiological
production of hydrogen
•
Modify protein structure of hydrogenase
enzyme to exclude oxygen from active site while still allowing protons to enter and hydrogen to exit
•
Use a cell-free protein evolution approach to:Express and activate hydrogenase enzymeProduce an uncoupler protein to aid flow of protonsOptimize organism for resistance to light exposure and to infection
•
Test hydrogen production in photobioreactor
set-up.
•
Engineer Synechocystis organism to demonstrate photobiological
production of hydrogen
•
Modify protein structure of hydrogenase
enzyme to exclude oxygen from active site while still allowing protons to enter and hydrogen to exit
•
Use a cell-free protein evolution approach to:Express and activate hydrogenase enzymeProduce an uncoupler protein to aid flow of protonsOptimize organism for resistance to light exposure and to infection
•
Test hydrogen production in photobioreactor
set-up.
Direct Solar Biohydrogen Jim Swartz
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Monitoring and Accessing Cellular Photosynthesis for Bioelectricity
Fritz Prinz and Arthur Grossman
Anode
Cathode
e-2H2
O → O2
+ 4H+
+ 4e-
hυ
• Capture electricity directly from living biological cells by inserting nano-scale electrodes into their chloroplasts
• Light-driven charge separation generates high potential electrons in stroma, and O2 and H+ in lumen
• Energy is generated through a current that results in recombination of electrons from stromal side of the membrane with H+ and O2 on lumenal side of the membrane (at cathode) to generate H2 O
• Explore using unicellular alga Chlamydomonas reinhardtii
• Capture electricity directly from living biological cells by inserting nano-scale electrodes into their chloroplasts
• Light-driven charge separation generates high potential electrons in stroma, and O2 and H+ in lumen
• Energy is generated through a current that results in recombination of electrons from stromal side of the membrane with H+ and O2 on lumenal side of the membrane (at cathode) to generate H2 O
• Explore using unicellular alga Chlamydomonas reinhardtii
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Directed Evolution of Novel Yeast Species Gavin Sherlock, Frank Rosenzweig
•
Improve the efficiency and flexibility of biomass conversion through development of novel, adaptively evolved, hybrid yeast strains.
Saccharomyces cerevisiae is able to ferment the hexose sugars in cellulose to ethanolEvolve the organism to also include the ability to produce ethanol by the fermentation of pentose sugars, xylose and L-arabinose, present in hemicellulose
•
Allows use of all of the substrate found in cellulosic and hemicellulosic
feedstocks
•
Improve the efficiency and flexibility of biomass conversion through development of novel, adaptively evolved, hybrid yeast strains.
Saccharomyces cerevisiae is able to ferment the hexose sugars in cellulose to ethanolEvolve the organism to also include the ability to produce ethanol by the fermentation of pentose sugars, xylose and L-arabinose, present in hemicellulose
•
Allows use of all of the substrate found in cellulosic and hemicellulosic
feedstocks Process to create hybrid yeast species
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Microbial Synthesis of Biodiesel Chaitan
Khosla
Engineer E. coli as a microbial factory for production of fatty acids:
Increase carbon flux (acetyl-CoA) to fatty acid biosynthesis synthesis (malonyl-CoA) by expressing genes from two key control enzymesBiosynthesize fatty acid alternatives (e.g. aldehydes, esters and lactones), using existing fatty acid pathways and heterologous enzymes, and evaluate their quality and potential as biodiesel fuelsCo-express plant oleosin genes to accumulate higher concentrations of fatty acids
Engineer E. coli as a microbial factory for production of fatty acids:
Increase carbon flux (acetyl-CoA) to fatty acid biosynthesis synthesis (malonyl-CoA) by expressing genes from two key control enzymesBiosynthesize fatty acid alternatives (e.g. aldehydes, esters and lactones), using existing fatty acid pathways and heterologous enzymes, and evaluate their quality and potential as biodiesel fuelsCo-express plant oleosin genes to accumulate higher concentrations of fatty acids
•
Direct biodiesel production from biomass feedstock using engineered microorganisms could have both a potentially high yield and the high energy density of a hydrocarbon
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Direct biodiesel production from biomass feedstock using engineered microorganisms could have both a potentially high yield and the high energy density of a hydrocarbon
O
R S-ACP
Glucose
Protein-boundFatty Acids
FattyAlcohols
FattyAldehydes
Fatty AcidEsters
Alkanes
O
R OR'
O
R H
R OH
RH
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Genetic Engineering of Cellulose Accumulation Chris Somerville
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Increase accumulation of cellulose and carbon uptake in biomass crops by genetic alteration of the regulation of cellulose synthesis
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Transgenic plants will be produced in which the components of the cellulose synthase complex are produced in increased amounts and
at altered times during plant development.
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Increase accumulation of cellulose and carbon uptake in biomass crops by genetic alteration of the regulation of cellulose synthesis
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Transgenic plants will be produced in which the components of the cellulose synthase complex are produced in increased amounts and
at altered times during plant development.
Cell walls
Electron micrograph of a cell wall
Cellulose Synthase
Cellulose fibrils
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Biomass energy: the climate protective domain
Chris Field, Roz Naylor, Greg Asner, David Lobell
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Constraints•
Global Carbon Cycle
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Agriculture•
Biomass Energy
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Constraints
Food Fuel
Fossil offsets
Other emissions
Energy
Nature
21USDA Amber Waves 2007
Biofuels and food
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Setting the scale
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Food for 1 person for one year–
~ 250 kg corn
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= ethanol for one fill-up–
~ 80 l (20 gal)
•
At 25 mpg and 10,000 miles/y–
The corn required to fuel one car on corn ethanol
–
Would feed 20 people–
Would require 1 Ha of farmland
Hill et al PNAS 2006
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Net energy balance ratio
(biomass energy out/fossil energy in)
•
Corn ethanol ~1.2•
Sugarcane ethanol ~ 8
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Soy biodiesel ~ 2•
Palm biodiesel ~ 9
•
Cellulosic ~5(?)
Fargione et al. Science 2008
Carbon “debt”
from expanding agriculture
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Land Type
Area (Mha)
Mean NPP(ton C/ha/y)
Total NPP(Pg C/y)
Total Energy*(EJ/y)
Global Crop 1,445 4.6 6.7 119
Pasture 3,321 3.4 11.3 200
US Crop 173 5.7 1.0 18
Pasture 226 3.5 0.8 14
Global Primary Energy = 480 EJ/y* In ½
biomass (to allow for roots), assume 45% C
Energy in ag and pastures?
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Will yields increase dramatically?
•
Historical trends –
a century of success–
1-2%/y for major crops
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Will this continue?–
Can it accelerate?
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Ag yields –
a century of success increases of 1-2% y-1
Lobell and Field ERL 2007
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Global area, production, and yield changesfor six major world crops
Wheat rice maize barley soybean sorghum2002 Area (Mha) 214 148 139 55 79 422002 Production (Mt yr-1) 574 578 602 137 181 54Yield change, 1981-2002 (kg/ha) 846 1109 1178 473 632 -80
In energy units –
1.5 Pg Biomass ≈
30 EJ
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•
Ag in relation to natural NPP–
Ag/NPP --
Globally about 65%
•
Global average crop yields unlikely to exceed natural NPP for at least the next several decades
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Agriculture’s future
Moore’sLaw
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Extracting climate sensitivity
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First difference yield•
Define locally-weighted climate
•
Regress against–
Growing season tmax
, tmin
, precip–
Define growing season based on explained variance
•
Reconstruct trend with (observed) and without (climate corrected) climate
37Lobell and Field ERL 2007
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Global area, production, and yield changesfor six major world crops
Wheat rice maize barley soybean sorghum2002 Area (Mha) 214 148 139 55 79 422002 Production (Mt yr-1) 574 578 602 137 181 54Yield change, 1981-2002 (kg/ha) 846 1109 1178 473 632 -80Climate driven yield change, 1981-2002 (kg/ha) -60.1 -6.5 -89.5 -140.3 23.1 -20.0Climate driven production change, 1981-2002 (Mt yr-1) -12.9 -1.0 -12.4 -7.8 1.8 -0.8
39Lobell and Field ERL 2007
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Bioenergy: the climate protective domain
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Increase growth•
Increase efficiency of conversion to useful products
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Utilize sites where C loss from conversion is small in relation to bioenergy yield
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Utilize sites that are not needed for something else
Field, Campbell, Lobell TREE 2008
Field et al TREE 2008
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Land Type Area (Mha)
Mean NPP(ton C / ha / yr)
Total NPP(Pg C / yr)
Global Crop 1,445 4.6 6.7
Pasture 3,321 3.4 11.3
Abandoned 474-579 4.7 2.2-2.7
Potential from abandoned land
Campbell et al ES&T 2008
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Land Type Area (Mha)
Mean NPP(ton C / ha / yr)
Total NPP(Pg C / yr)
Global Crop 1,445 4.6 6.7
Pasture 3,321 3.4 11.3
Abandoned 474-579 4.7 2.2-2.7
In Forest 72 6.5 0.5
In Urban 18 5.0 0.1
In Other 385-472 4.3 1.6-2.1
From available abandoned land
1.6 –
2.1 Pg C x 2 g Plant/g C x 0.5 g top/g plant x 20 EJ/Pg = 32 -
41 EJ= 7-8% of current global energy system
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Bioenergy
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Climate impact depends on pre-existing ecosystem
•
Indirect as well as direct paths to carbon loss•
Natural NPP reasonable proxy for potential yield under ag management
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Available land resource limited–
Quantity and quality
•
Big potential in absolute terms•
But a small slice of present or future demand
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Future energy needs: Many times current
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Biomass energy
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Corn $275/ton
•
Coal Power River
$15/ton
Central Appalachia
$149/ton
•
Crude oil $1000/ton