; Graham
Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out

Graham

VIEWS: 67 PAGES: 34

  • pg 1
									Reflections on the DOE/USDA report on
the technical feasibility of a billion-ton
     annual supply of biofeedstocks


              Robin L. Graham
       Oak Ridge National Laboratory

         Workshop on Critical Issues in Climate Change
                        Biotechnologies:
        Land, Production, Transformation and Economics
                      Snowmass, Colorado
                        August 2, 2006
http://www1.eere.energy.gov/biomass/pdfs/final_billionton_vision_report2.pdf
     WHAT WAS THE PURPOSE OF THE STUDY?

• To determine whether the land resources of the U.S. are
  capable of producing a sustainable supply of biomass sufficient
  to displace 30% of the country’s present petroleum consumption
  – approximately equivalent to one billion dry tons.

• Goal was set by a joint advisory committee to the DOE and
  USDA as a vision for making a major contribution to U.S. energy
  needs by 2030
   – 5% of the nation’s power
   – 20% of the nation’s transportation fuels
   – 25% of the nation’s chemicals & materials from biobased
     products
         WHAT WAS THE Motivation OF THE STUDY?

•   In 2004, estimates of current and future biomass availability in the US
    were a confusing (a mess?)
     –    Existing vs potential?
     –    Physically available vs economically available?
     –    Wet wt vs dry wt; mass vs energy content
     –    Lots of resource type specific studies with differing underlying assumptions.
          ( e.g. differing resource estimates double counting the land base)
     –    Regional vs national studies
     –    Confusion between stocks and annual supply - especially for forest-derived
          resources
     –    Often assumptions not given
     –    Environmental and/or operational constraints to collection often not
          accounted for

         National level
         -Ugarte et al 2004 – energy crops w/ price & competition
         -Graham et al 1997- energy crop yield, acreage, cost
         -Graham 1994 – energy crop land base & yield
         -Gallager et al 2003 – residues w/price & competition
         -Haq 2002- all resources w/price
       WHAT WAS THE Motivation OF THE STUDY?

• In 2004, because of the confusion concerning
  resource availability, it wasn’t clear whether or not
  bioenergy could play a significant role in the US
  energy. Nor was it clear what types of resources
  were most worthy of pursuit from the perspective of
  potential quantity.
   – Lots of “pet” resources
   – Need to target R&D on nationally significant resources

• Need for a document which
   –   Addressed ALL resources
   –   Clearly stated assumptions
   –   Was acceptable to USDA
   –   Was written for a wide audience
              RESOURCE ANALYSIS APPROACH

• Did not consider resource costs or policy changes required
  for land use, agriculture, and fuels & vehicles
   – Viewed our study as the first step.
   – Wanted to be viewed as neutral, not pushing a viewpoint.
   – RBAEF study ongoing and we wanted to be complimentary

• Took a conservative tactic to answering the question –
  assumed business-as-usual in both the Ag and forest sector
   – Felt we needed to answer the question from a conservative
     viewpoint
   – Felt the knowledge base was adequate to answer the question we
     posed
   – Wanted the numbers to be transparent
       Overview of RESOURCE ANALYSIS APPROACH


• Forest resource estimates based on analysis of
  existing resources, uses, and trends in the demand
  for forest products
   – Timberlands and other forestlands (public and private)
   – Provides multiple-use benefits (e.g., wildlife habitat,
     recreation, and ecological and environmental services)
   – Managed less intensively, more inertia to rapid change


• Agricultural resource estimates based on scenarios
  extrapolated from current food/feed trends and R&D
   – Active cropland managed intensively on year-to-year basis
   – Idle cropland and pasture for perennial crops (grasses and
     woody crops)
            THE BIOMASS FEEDSTOCK RESOURCE BASE

• About one-half of the land in the contiguous U.S.
   – Forestland resources: 504 million acres of timberland, 91 million
     acres of other forestland
   – Agricultural resources: 342 million acres cropland, 39 million
     acres idle cropland, 68 million acres cropland pasture

• Forest resources                  • Agricultural resources
   – Logging residues                   –   Crop residues
   – Forest thinnings (fuel             –   Grains to biofuels
     treatments)                        –   Perennial grasses
   – Fuelwood                           –   Perennial woody crops
   – Primary wood processing mill       –   Animal manures
     residues                           –   Food/feed processing residues
   – Secondary wood processing          –   MSW and landfill gases
     mill residues
   – Pulping liquors
   – Urban wood residues
         THE BIOMASS FEEDSTOCK RESOURCE BASE
                                          Target
                    1+ Billion Tons of Biomass Resources Available for
                                 Bioenergy and Bioproducts
                        (Excludes conventional Food/Feed/Fiber)



                                       Biomass from               Other Secondary and
Biomass from           Currently        Agricultural              Tertiary Biomass from
Forest Lands           Collected
                                          Lands                   Ag. and Forest Lands
                       and Used


               Wood and Residues                                                   MSW and
               to Pulp & Paper and               Grain Crops                      Urban Wood
                Forest Product Mills                                                 Waste

                                                                                     Animal
                                                  Oil Crops
               Fuel Wood                                                            Manures

                                                                                      Food
                                                                                   Processing
                Logging and                      Agricultural                       Wastes
               Other Removal                      Residues
                 Residues


              Fuel                                Perennial
           Treatments                             Grasses
                                                                   Energy crops
                                                   Woody
                                                   Crops
CORN STOVER - LARGEST RESIDUE RESOURCE
          Amount is dependent on crop yield, collection
     equipment, tillage practices, and environmental restrictions
   SWITCHGRASS PRODUCED IN 10 YEAR
ROTATIONS WITH ANNUAL HARVEST, USING
 CONVENTIONAL AGRICULTURAL EQUIPMENT
 POPLARS GROWN ON CROPLAND AT 8-12FT
SPACINGS, 6-10 YR ROTATIONS, HARVESTED
       WITH FORESTRY EQUIPMENT




 Early 2nd yr poplar growth
WILLOW PRODUCED ON CROPLAND AT 1-3 FT
 SPACINGS, HARVESTED IN 3 YEARS WITH
        SPECIALIZED EQUIPMENT




                       Willow at harvest age
Fuel treatment thinning operations
                              Forest resources
•   Logging residues
     –   From conventional harvest – tops, branches NOT needles/leaves
     –   Forest management ( rough & rotten wood) and land clearing for logging roads etc

•   Fuel treatments – forest thinning to reduce susceptibility to catastrophic wild
    fire

•   Fuelwood – e.g. for wood stoves

•   Wood residues from forest products
     –   Primary residues -fine (e.g. sawdust) ,coarse ( e.g. slabs), bark
     –   Secondary residues ( fine & coarse)

•   Pulping liquor

•   Urban wood waste
     –   Discarded wood waste ( pallets, packaging materials, wood scraps)
     –   Yard trimmings
     –   Construction & demolition
           RESIDUES FROM LOGGING,
         SILVICULTURAL OPERATIONS &
          CLEARING OF TIMBERLANDS
• Timber Product Output database
• 70 million dry tons generated
  annually
• Collected concurrently with
  operations
• 50% to 65% of biomass is
  recoverable (public vs private
  lands)
• All recovered material (~ 41
  million dry tons/year) for
  biomass uses
• Estimated to increase to ~ 64
  million dry tons/year
    RESIDUES FROM FUEL TREATMENT
             OPERATIONS
•   Timberlands
     – Fuel Treatment Evaluator used to
       identify biomass requiring removal
     – Recovery of 85% of the identified
       biomass
     – Accessibility – 60% for public lands
       and 80% for private lands
     – Biomass fraction – 30% (70%
       conventional forest products)
     – Collection cycle – 30 years

•   Other forestlands
     – Forest Inventory Analysis database
       used to identify biomass (50%
       removal)
     – Recovery of 85% of the identified
       biomass
     – Accessibility – 60% for public lands
       and 80% for private lands
     – Biomass fraction – 90%
     – Collection cycle – 30 years
FOREST RESOURCE SUMMARY ~ 368 M ton/yr in 2030
Logging and other removal residue
Fuel treatment thinnings - timberlands
Fuel treatment thinnings – other forestland
               AGRICULTURAL RESOURCES
• Took a scenario approach because
   – Unlike forests, cropland is intensively managed and on a short
     time frame so over the next 30-50 years there are lots more
     “options”
   – Needed to include the possibility of energy crops and currently
     there are none so you can’t really extrapolate
• Did ground the scenarios utilizing USDA research data and
  expert opinion
   – USDA-NASS: Agricultural Statistics 2003 (2001 crop data)
   – USDA-OCE: Baseline Projections to 2012 & 2013
   – USDA-ARS: National Agronomy Manual
   – USDA-ARS: R&D on forage soybeans yield and residue
   – USDA-NRCS: Soil Conservation Index version 25
   – USDA-ERS: Confined animal and manure data
   – Corn & wheat residue analyses (Graham et al)
   – Corn planting density effects research (U. of Nebraska & Pioneer
     Hi-Bred)
   – DOE - Roadmap for Agricultural Biomass Feedstock Supply
   – FAO and UN population and crop yield projections
   – Literature - yield potential and crop residue management
       Agricultural biomass resources

•   Other residues – MSW & animal fats & corn fiber not used for animal feed
•   Manures - from confined feedlots in excess of what can be applied on farm
•   Grain to fuel – sugars, starch and oils
•   CRP biomass – harvest 1 ton/acre, no harvest on CRP for wildlife
•   Other crop residues – rice, cotton lint
•   Soybean residues – development of new varieties with much higher residue/grain
    ratio ( e.g. much lower harvest index)
•   Small grain residues other than wheat – barley, oats
•   Wheat straw
•   Corn stover
•   Perennial energy crops – switchgrass, poplar, willow (ylds 5 or 8 dry tons/acre)
        AGRICULTURAL RESOURCES considered by scenario

                Current   Mod yld     High yld    Mod yld       High yld
                          No energy   No energy   Energy crop   Energy crop
   Other           Yes       Yes         Yes         Yes           Yes
  residues
  Manures          Yes       Yes         Yes         Yes           Yes
Grain to fuel      Yes       Yes         Yes         Yes           Yes
CRP biomass                  Yes         Yes         Yes           Yes
Other crop         Yes       Yes         Yes         Yes           Yes
 residues
  Soybean                                            Yes           Yes
  residues
Small grain        Yes       Yes         Yes         Yes           Yes
 residues
Wheat straw        Yes       Yes         Yes         Yes           Yes
Corn stover        Yes       Yes         Yes         Yes           Yes
  Perennial                                          Yes           Yes
energy crops
                AGRICULTURAL RESOURCE ANALYSIS
•   Approach (“what if”) based on available information & expert opinion on
    potentials (e.g., crop yields, equipment efficiency, etc.)
•   Crop yields (annual and perennial crops)
     – 15% to 50% for annual crops
     – 5 to 8 dry tons/acre/year for perennial crops
•   Residue to grain ratios
     – Vary by crop; only soybean ratios change in scenarios
•   Harvest/collection efficiency
     – 40%, 60%, 75%
•   Tillage practices (no-till)
     – Current tillage with changes up to 100% no-till
•   Allocation of cropland acres
     – Perennial crops accommodated with reductions in active cropland, idle
         cropland, and cropland pasture
•   Used current trends, research directions and previous analysis results such as:
     – 30 yr average corn yield increase at 1.7 bu/ac
     – Research to develop soybeans with higher forage content (higher residue to
         grain ratio)
     – Research to develop more efficient and one-pass harvesting equipment
     – Increasing levels of no-till management
     – POLYSYS analysis indicating potential acreage available to energy crops
         under various market conditions.
•   Consultation with USDA scientists
            Ground rules – No perennial energy crops

•   Without energy crops –
    – Acreage of conventional crops fixed at USDA 2014
      projections
    – Corn and soybeans could go to fuel only after food, feed and
      export met
       • Food = 2014 baseline or 137% of current ( pop increase in 50yrs)
       • Feed = 2014 baseline or 137% of current ( pop increase in
         50yrs)
       • Export = 2014 baseline or higher
    – Tillage shifts to no-till to allow more residues removal
       • 200 M acres to all acres
    – Residue
       • collection efficiency increases 60% or 75%
       • Enough left to prevent unacceptable erosion
    – Crop yields increase
       • Corn & wheat – 25 to 50% increase
       • Rest – 15-30% increase
    – Manure – only from confined animal feed operations
              Ground rules – With perennial energy crops

•   With energy crops –
    – Acreage of conventional crops fixed at USDA 2014 projections except under
      high scenario when
        •   Wheat acreage loses 5 M (52.3 to 47.3)
        •   Soybeans lose 8 M (71.4 to 63.4)
        •   Other hay loses 5 M (34.2 to 29.2)
        •   Remaining acreage comes from cropland used for pasture, idle, and CRP used for
            grasses
    – Corn and soybeans could go to fuel only after food, feed and export met
        • Food = 2014 baseline or 37% higher than current ( pop increase in 50yrs - FAO)
        • Feed = 2014 baseline or 37% higher than current ( pop increase in 50yrs)
        • Export = 2014 baseline or higher
    – Tillage shifts to no-till to allow more residues removal
        • 200 M acres to all acres
    – Residue collection
        • efficiency increases 60% or 75%
        • Enough left to prevent unacceptable erosion
    – Crop yields increase
        • Corn & wheat – 25 to 50% increase ( 2020 & 2043)
        • Rest – 15-30% increase
    – Energy crop yields – 5 or 8 dry tons/acre/yr but 10% loss in harvesting
          CURRENT AVAILABILITY OF BIOMASS FROM
                        CROPLAND

• Total current
  availability of
  biomass is ~
  190 million dry
  tons/year
• Slightly more
  than one-fifth
  is currently
  used
• Corn stover is
  largest source
  of agriculture-
  derived
  biomass
    CROPLAND BIOMASS POTENTIAL WITH ENERGY CROPS
•   Potential from all cropland biomass resources approaches 1 billion dry
    tons/year
•   Primary sources alone are 420 – 800 million dry tons
•   Perennial crops  average harvested yield 4.7 – 7.4 dry tons/ac; 40 - 60
    million acres
          WHAT IS THE CROPLAND POTENTIAL?
•   Total resource  560 to 930 million dry tons/year
     –   Yield increase of 25 - 50% for corn and other small grains, 15 - 30% for other crops
     –   Change in tillage practices
     –   Residue collection equipment
     –   Residues from soybeans
     –   The allocation of active cropland, idle cropland, and pasture to perennial crops
      so..ARE THERE potentially
       SUFFICIENT BIOMASS
     RESOURCES TO REPLACE A
    SIGNIFICANT FRACTION OF
    THE NATION’S PETROLEUM
     REQUIREMENTS by 2030?



•   Yes, land resources could
    provide a sustainable supply
    and still meet food, feed,
    and export demands

•   Estimates are reasonable
    given trends and time for
    biorefinery scale-
    up/deployment
                          SUMMARY

• Primary land
  resources (i.e., crop
  residues, perennial
  energy crops, and
  forest residues) are
  sufficient to support
  30% replacement of
  gasoline use by 2030

• Use of cropland and
  forestland biomass
  resources could
  support biorefineries
  in all 50 States         Current capacity is a small fraction of potential
                          (map shows biochemical only – no manure, MSW)
                              Issues

• Policies needed to effect change – agriculture, land use,
                Conclusion
  and fuels & vehicles
                       conclusion
• Coordinated Technology change and RD&D needed
   – Yields & residue/grain ratios
   – Tissue quality
   – Reduction of nitrogen fertilizer without loss of yield
         • Water quality
         • Energy
         • Genetic solutions/Agronomic solutions ( e.g. rotations)
   –   Harvesting
       Conclusion & on farm preprocessing
   –   Storage of residues and grasses
   –   Forest harvest technology
                       Issues

• Environmental uncertainties ( positives and
  negatives) Conclusion
   – Impacts of residue removal on soil carbon & wildlife
     and nutrientsconclusion
   – Impacts of energy crops on soil - enhanced
     sequestration
   – Water quality & quantity w/energy crops (quality is a
     generally positive; quantity?)
   – Wildlife impacts as a result of land use & management
     change – forests and croplands
     Unintended
   – Conclusion geneflow from genetically modified
     organisms to native populations
• Some tools for evaluating these issues – EPIC,
  Century, SCI, RUSLE
• Uncertain ownership of these issues – site
  specificity of response. Difficult to generalize.

								
To top
;