Stanford UniversityGlobal Climate & Energy Project

Biomass Energy: the Climate Protective Domain

Christopher Fieldwww.global-ecology.org

GCEPCarnegie Institution for Science

Stanford university

July, 2008

2

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

7

Bioenergy:

A great green hope or impending disaster?

•

A climate-friendly liquid fuel•

Target of immense hype and speculation

•

Threat to climate, biodiversity, and rural lifestyles

8

How can biofuels

be lower carbon?

•

Photosynthesis–

Light + CO2

plant + O2

•

Plant combustion–

Plant + O2

energy + CO2

•

Net–

Light + CO2

energy + CO2

9

The hope

•

Net fossil fuel offset•

Big slice of the future energy system

•

Increased income source for rural areas•

Acceptable environmental implications

10

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

•

US DOE funds 3 biofuels

centers at $125 million each

•

Hot trend in venture capital

11

The threat

•

Decreased food security•

Decreased water security

•

Net warming•

Ocean and freshwater pollution

•

Loss of conservation areas•

Loss of biodiversity

•

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

12

GCEP: Using the wheat and the chaff

•

Re-engineering photosynthesis•

Re-engineering biofuels

processing

•

Re-engineering plants to facilitate biofuels production

•

Finding the climate-protective domain

13

Climate-protective biofuels

•

Grow more plants–

Without more environmental downsides

•

Get more energy per unit of plant biomass•

Figure out where it does and doesn’t make sense to produce biofuels

1414

•

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

15

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

16

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

1717 17

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

•

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

18

Genetic Engineering of Cellulose Accumulation Chris Somerville

•

Increase accumulation of cellulose and carbon uptake in biomass crops by genetic alteration of the regulation of cellulose synthesis

•

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.

•

Increase accumulation of cellulose and carbon uptake in biomass crops by genetic alteration of the regulation of cellulose synthesis

•

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

19

Biomass energy: the climate protective domain

Chris Field, Roz Naylor, Greg Asner, David Lobell

•

Constraints•

Global Carbon Cycle

•

Agriculture•

Biomass Energy

20

Constraints

Food Fuel

Fossil offsets

Other emissions

Energy

Nature

21USDA Amber Waves 2007

Biofuels and food

22

Setting the scale

•

Food for 1 person for one year–

~ 250 kg corn

•

= 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

24

Net energy balance ratio

(biomass energy out/fossil energy in)

•

Corn ethanol ~1.2•

Sugarcane ethanol ~ 8

•

Soy biodiesel ~ 2•

Palm biodiesel ~ 9

•

Cellulosic ~5(?)

Fargione et al. Science 2008

Carbon “debt”

from expanding agriculture

26

27

28

29

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?

30

Will yields increase dramatically?

•

Historical trends –

a century of success–

1-2%/y for major crops

•

Will this continue?–

Can it accelerate?

31

Ag yields –

a century of success increases of 1-2% y-1

Lobell and Field ERL 2007

32

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

33

•

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

33

34

Agriculture’s future

Moore’sLaw

35

36

Extracting climate sensitivity

•

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

38

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

40

Bioenergy: the climate protective domain

•

Increase growth•

Increase efficiency of conversion to useful products

•

Utilize sites where C loss from conversion is small in relation to bioenergy yield

•

Utilize sites that are not needed for something else

Field, Campbell, Lobell TREE 2008

Field et al TREE 2008

44

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

45

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

46

47

Bioenergy

•

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

•

Available land resource limited–

Quantity and quality

•

Big potential in absolute terms•

But a small slice of present or future demand

48

Future energy needs: Many times current

49

Biomass energy

•

Corn $275/ton

•

Coal Power River

$15/ton

Central Appalachia

$149/ton

•

Crude oil $1000/ton