BIOFUELS, INDIRECT LAND USE CHANGE,

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BIOFUELS, INDIRECT LAND USE CHANGE, LIFE CYCLE
ANALYSIS DO WE NOW KNOW ENOUGH TO KNOW THAT WE
DONT KNOW?

• Bruce E. Dale
• University Distinguished Professor of Chemical
  Engineering
• Michigan State University
• Presented at
• Low Carbon Fuels Webinar
• July 25, 2008

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My Assumptions/Points of Departure

• Inexpensive plant raw materials will catalyze the
  growth of new and existing biofuel industries
  this is absolutely going to happen
• We have a unique opportunity to design these
  industries for better environmental performance
• One important tool life cycle analysis (LCA)
• LCA has significant value if used properly, but
  it is a limited tool
• LCA exists to make comparisonsLCA should not be
  done in the ideal or the abstract

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Life Cycle Assessment Framework
Goal and Scope Definition
Interpretation Stakeholder Participation
Direct applications - Product development -
Marketing and improvement - Strategic planning -
Public policy formation - Other
Inventory Analysis
No stakeholder involvement in either Science
paper
Impact Assessment
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EISA 2007 renewable fuels must meet
certain lifecycle greenhouse gas emission
reductions
It aint a life cycle analysis just
because someone says it is. An LCA study must
meet certain standards
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Some Life Cycle Analysis Standards In Plain
English

• Use the most recent/most accurate data possible
• If models are used to generate data, have the
  models been sufficiently tested verified?
• Select the reference system/functional unit what
  exactly are we comparing?
• Make it easy for others to check your data and
  methods transparency (difficult for complex
  models)
• Set clear system boundaries (physical
  temporal)must be equal or comparable for
  reference system and/or reference product of
  interest
• Multi-product systems must allocate environmental
  costs among all products
• Perform sensitivity analysis how much do results
  vary if assumptions or data change?

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The Policy Related Tasks Are

• Use life cycle analysis to
• Determine the greenhouse gas impacts of...
• Direct land use changesand
• Indirect land use changes (ILUC)
• Do the two ILUC studies (February 2008 Science
  papers) meet commonly accepted LCA standards and
  thereby satisfy the policy requirements or do
  they not meet these standards?

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Lets Examine the Recent Papers in Science using
these Criteria

• Use the most recent/most accurate data possible
• If models are used to generate data, have the
  models been sufficiently tested verified?
• Select the reference system/functional unit what
  exactly are we comparing?
• Make it easy for others to check your data and
  methods transparency (difficult for complex
  models)
• Set clear system boundaries (physical
  temporal)must be equal or comparable for
  reference system and/or reference product of
  interest
• Multi-product systems must allocate environmental
  costs among all products
• Perform sensitivity analysis how much do results
  vary if assumptions or data change?

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Use the most recent most accurate data
possible

• Land clearing from the 1990snot checked by
  either modeling or more recent data
• Ignores literature on causes of land use change
• Four linked submodelsno empirical data at all
• Ethanol demand to corn price
• Corn price to corn or soybean supply
• Corn or soybean supply to land use change
• Land use change to greenhouse gas consequences
• Land management post land use change not
  considered-apparently only plow tillage used
• Sensitivity analyses were generally incomplete or
  lacking (Monte Carlo simulation is the standard)
• No confirmation of model predictions by 1)
  empirical data, 2) other models, or 3) back
  testing.
• An unverified, untested model is simply a guess.

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Select the reference system or functional unit
what exactly are we comparing?

• Ethanol vs. Gasoline?
• Corn ethanol vs. cellulosic ethanol vs. tar sands
  oil to gasoline?
• Gasoline produced how, when and from what? (oil
  shale, tar sands, heavy crude???)
• Backwards looking or forward looking (temporal
  boundaries)?
• Corn for ethanol vs. corn for animal feed?
• Allocation would help resolve feed vs. fuel uses
  of landthis was apparently not done in either
  analysis

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Set clear system boundaries (physical
temporal)must be comparable for reference
product of interest

1. Ethanol temporal future (forward looking)
2. Ethanol physical entire world land (indirect
   effects on GHG considered)
3. Petroleum fuels (or other alternatives) temporal
   past (GREET model)
4. Petroleum fuels physical restricted (indirect
   effects on GHG not considered)

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Multi-product systems must allocate environmental
costs among all products

• System is land use in the entire world
• Land produces
• Animal feed (roughly 10x direct human food use)
• Human food
• Biofuels
• Pulp, paper, lumberand lots more
• Searchinger, et al, paper apparently allocated
  the entire incremental land use change cost of
  biofuel production to the biofuel
• Ignores the fact that the replaced agricultural
  production went to provide animal feed
• Without allocation, these analyses advantage
  animal feed from land vs. biofuels production.
• Could have/should have dealt with this allocation
  issue in the sensitivity analysis

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Perform sensitivity analysis how much do results
vary if assumptions or data change?

• Productive use of existing forest make furniture
  or flooring from the tropical hardwoods or were
  the trees just burned?
• Decreased land clearing rates and/or different
  ecosystems converted. What if most land converted
  is pasture?
• Historical rates of corn yield increase in the
  U.S. abroad
• Carbon debt compared with Athabasca oil
  sands/Colorado oil shale/Venezuelan heavy crude
  GHG in 2015 vs. GREET in 1999
• Increasing efficiency of future ethanol plants
• Uncertainties in global equilibrium modelstest
  through Monte Carlo simulation? Tested with
  data? Other models?
• Allocation of environmental burdens among feed
  and fuel uses of corn(livestock are responsible
  for 18 of worldwide GHG emissions)
• How is land managed after conversion?
• These other factors were not adequately
  addressed during sensitivity analysis

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Do the 2008 Science Papers Meet LCA Criteria?

• Data quality. Use the most recent/most accurate
  data possible? No. Models may be valid but that
  was not proven. Literature on causes of land use
  change ignored?
• Select the reference system/functional unit what
  exactly are we comparing? Marginal.
• Make it easy for others to check your data and
  methods transparency Acceptable

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Do the 2008 Science Papers Meet LCA Criteria?

• Set clear system boundariesmust be equal or
  comparable for reference system and/or reference
  product of interest No. Temporal boundaries
  physical boundaries are not comparable for
  ethanol gasoline
• Multi-product systems must allocate environmental
  costs among all products No. No apparent or
  stated allocation of these costs among animal
  feed and biofuels
• Perform sensitivity analysis how much do results
  vary if assumptions or data change? No.
  Sensitivity analysis lacked appropriate range of
  variables, especially for allocation
• No apparent stakeholder involvement

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So What is My Bottom Line?

• GHG effects of direct land use change for
  biofuels (supply chain oriented) can and have
  been studied by LCA. Robust conclusions by LCA
  standards (/- 30)
• GHG effects of indirect land use change (market
  oriented) have not yet been successfully studied
  by LCA. Science papers are not (and probably were
  not intended to be) LCA studies.
• Existing ILUC papers do not meet the standards
  for life cycle studies. It is simply incorrect
  to use them as such.
• The system is so complex that it may never be
  possible to apply recognized LCA standards to
  ILUC (but that shouldnt stop us from trying)

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Land Management Post Land Use Change Some
Insights

• Ethanol demand to corn price
• Corn price to corn or soybean supply
• Corn or soybean supply to land use change
• Land use change to greenhouse gas consequences
• Land management post land use change
• Land doesnt cease to be managed once the land
  use change is executed.
• What are the GHG consequences of post land change
  management options?

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Land Management Post Land Use Change Tillage
Practices Cover Crops
Scenario Description
A Convert grassland to cornfield dedicated to ethanol production
B Divert cornfield to ethanol production, Convert grassland to cornfield dedicated to animal feed production
C Convert corn-soybean rotation to cornfield dedicated to ethanol production Convert grassland to corn-soybean rotation
D Convert forest to cornfield dedicated to ethanol production
E Divert cornfield to ethanol production, Convert forest to cornfield dedicated to animal feed production
F Convert corn-soybean rotation to cornfield dedicated to ethanol production Convert forest to corn-soybean rotation
Data for DAYCENT from 8 U. S. corn producing
counties, different climates, etc.
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Current tillage
Plowing tillage
No tillage
Cover crop
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A Path Forward for LCA and ILUC?

• GTAP deals only with land for which rents are
  established cropland, pasture commercial
  forest (not Amazon rainforest). Abandoned and
  CRP lands are not in the model
• Expand GTAP (or related models) to include
  abandoned land (1 billion acres world wide) CRP
  lands here
• Pasture (grassland) conversions do not seem to
  incur much carbon debt they may in fact get
  quickly to carbon credit
• Focus carbon debt analysis on forests (
  savannah?)
• Use common tool (DAYCENT?) to model forest
  conversion and post conversion management
  (standing biomass?)
• Three forest issues are 1) commercial forest, 2)
  non-commercial forests reduced reforestation
  rates
• If U.S. commercial forests, we can track
  discourage conversion using specific policy
  instruments-not ILUC blunt force trauma
• Carbon sequestration lost by reduced
  reforestation occurs over time can be estimated
  if reliable reforestation rates are known
• For non commercial forests, an academic land use
  literature exists but apparently has not been
  used in analysis to date agricultural expansion
  is only one of several driving factors.
  Allocation?

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One Tree (Study) Doth Not a Forest (Conclusion)
Make

• In science, one or two studies are never enough
  to establish the facts. SF papers began an
  important conversation
• Some key results of further (other) studies thus
  far
• Forests matter in carbon debt, grasslands may
  give carbon credit
• Forest conversions driven by combined forces
  agricultural expansion timber utilization
  road access explain 96 of observed cases but any
  single factor explains less than 20
• Land management post land change really affects
  GHG results
• One billion acres of unused/abandoned land
  worldwide, not considered in SF (nor were CRP
  lands)
• Models relatively untested do not validate each
  other well.
• Searchinger predicts land conversion in Latin
  America, China, U.S., etc
• Purdue (GTAP) predicts most conversion in U.S.
  (2/3 commercial forest)
• GTAP predicts ethanol expansion to date should
  have caused conversion of 2 million acres of
  forest. Did that happen?
• Duke (FASOMGHG) predicts mostly CRP pasture
  conversion in U.S.
• If FASOM is more correct, then ILUC may produce a
  carbon credit
• I believe we now know enough to know that we
  dont know the sign (positive or negative) of
  ILUC, let alone its magnitude.

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Questions ??