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H
Background Information on the Economic and Environmental
Assessment of Biomass Supply
The tables in this appendix present the background information and assumptions
that were used in the panel’s economic assessments and greenhouse-gas emission
analyses. They include comparisons of published and updated costs of harvest and
maintenance (Table H-1), nutrient replacement (Table H-2), transportation for delivery
(Table H-3), storage (Table H-4), and establishment and seeding (Table H-5) for different
cellulosic feedstocks. The published yield values from which current and future
projections were computed (Table H-6), and carbon-budget inputs for feedstock
production (Table H-7) and bioprocessing (Table H-8) are also included.
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TABLE H-1 Estimated Costs of Harvest and Maintenance for Cellulosic Feedstocks
Type of Type of Cost Cost per Ton Cost per Ton Reference
Feedstock (cited $) (2007 $)
Corn stover Baling, stacking, 26 45 Hess et al. (2007)
grinding
Corn stover Collection 31-36 66-77 McAloon et al. (2000)
Corn stover Collection 35-46 64-84 McAloon et al. (2000)
Corn stover Collection 17.70 17.70 R. Perlack, Oak Ridge
National Laboratory,
presentation to the
committee on November
19, 2007
Corn stover Up to storage 20-21 36-39 Sokhansanj and Turhollow
(2002)
Corn stover 28 36 Suzuki (2006)
Corn stover Baling, staging 26 47 Aden et al. (2002)
Corn stover Harvest 14 14 Edwards (2007)
Switchgrass Collection 12-22 16-28 Kumar and Sokhansanj
(2007)
Switchgrass Harvest 32 32 Duffy (2007)
Switchgrass Harvest 35 58 Khanna et al. (2008)
Switchgrass Harvest, 123.5/acre 210/acre Khanna and Dhungana
maintenance, (2007)
establishment
Switchgrass Harvest 15 26 Perrin et al. (2008)
Miscanthus Harvest 33 54 Khanna et al. (2008)
Miscanthus Harvest, 301/acre 512/acre Khanna and Dhungana
maintenance, (2007)
establishment
Nonspecific 10-30 15-45 Mapemba et al. (2007)
Nonspecific 23 38 Mapemba et al. (2008)
Harvest and maintenance costs were updated by using USDA NASS agricultural fuel, machinery,
labor prices from 1999-2007 (NASS, 2007a,b)
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TABLE H-2 Estimated Costs of Nutrient and Replacement for Cellulosic
Feedstocks
Type of Type of Cost Cost per Ton Cost per Ton Reference
Feedstock (cited $) (2007 $)
Corn stover 10.2 14.1 Hoskinson et al.
(2007)
Corn stover 4.6 8.4 Khanna and
Dhungana (2007)
Corn stover 7 14.4 Aden et al. (2002)
Corn stover 4.2 4.2 Petrolia (2008)
Corn stover 10 21 Perlack and Turhollow
(2003)
Corn stover Whole-plant 9.7 13.3 Karlen and Birrell
harvest (Unpublished)
Corn stover Cob, top 50% 9.5 13.1 Karlen and Birrell
harvest (Unpublished)
Corn stover Bottom 50% 10.1 13.9 Karlen and Birrell
harvest (Unpublished)
Switchgrass 6.7 12.1 Perrin et al. (2008)
Switchgrass 10.8 19.77 Khanna et al. (2008)
Miscanthus 2.5 4.6 Khanna et al. (2008)
Nutrient and replacement costs were updated by using USDA NASS agricultural-fertilizer prices from
1999-2007 (NASS, 2007a,b).
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TABLE H-3 Estimated Distance and Cost of Transportation for Delivery of
Cellulosic Feedstocks
Distance
Distance (miles) Type Reference
46-134 Round-trip Mapemba et al. (2007)
22-62 One-way Perlack and Turhollow
(2003)
22-61 One-way Perlack and Turhollow
(2002)
50 Round-trip Khanna et al. (2008)
50 Max one-way English et al. (2006)
50 One-way Vadas et al. (2008)
Transportation Cost1
Type of Type of Cost Cost Cited ($) Cost (2007 $) Reference
Feedstock
Corn stover Per ton 8.85 12.5 English et al. (2006)
Corn stover Per ton 10.25 27 Hess et al. (2007)
DVC2
Corn stover 0.15 0.35 Kaylen et al. (2000)
Corn stover Max DVC for 0.28 0.66 Kaylen et al. (2000)
positive NPV
Corn stover Per ton 10.8 10.8 Perlack (2007)
Presentation
Corn stover Per ton 13 31 Aden et al. (2002)
Corn stover Per ton 4.2-10.5 11-27.7 Perlack and
Turhollow (2002)
Corn stover DVC 0.08-0.29 0.17-0.63 Kumar et al. (2005)
DFC3 4.5 9.8
DFC range 0-6 0-13.3
Corn stover DVC 0.18 0.32 Searcy et al. (2007)
DFC 4 7.3
Corn stover DVC 0.16 0.38 Kumar et al. (2003)
DFC 3.6 8.6
Corn stover DVC Petrolia (2008)
0-25 miles 0.13-0.23 0.13-0.23
25-100 miles 0.10-0.19 0.10-0.19
>100 miles 0.09-0.16 0.09-0.16
DFC square bales 1.70 1.70
DFC round bales 3.10 3.10
Corn stover Per ton 10.9 13.8 Vadas et al. (2008)
Switchgrass Per ton 14.75 14.75 Duffy (2007)
1
Transportation costs were updated by using USDA NASS Agricultural-fuel prices from 1999-2007 (NASS,
2007a,b).
2
DVC, distance variable cost, per ton per mile.
3
DFC, distance fixed cost per ton.
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Switchgrass Per ton 19.2-23 27-32.4 Kumar and
Sokhansanj (2007)
Switchgrass Per ton 13 28 Perrin et al. (2008)
Switchgrass Per ton 10.9 13.8 Vadas et al. (2008)
Switchgrass or Per ton for 50 7.9 17.1 Khanna et al. (2008)
Miscanthus miles
Nonspecific Per ton 7.4-19.3 13.7-35.6 Mapemba et al.
(2007)
Nonspecific Per ton 14.5 31.5 Mapemba et al.
(2008)
Woody biomass Per ton 11-22 Summit Ridge
Investments (2007)
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TABLE H-4 Estimated Storage Costs for Cellulosic Feedstocks.
Type of Type of Cost Cost per Ton Cost per Ton Reference
Feedstock (cited $) (2007 $)
Corn stover 4.44 5.64 Hess et al. (2007)
Corn stover Round bales 6.82 6.82 Petrolia (2008)
Square bales 12.93 12.93
Switchgrass 16.67 16.67 Duffy (2007)
Switchgrass 4.14 5.18 Khanna et al. (2008)
Miscanthus 4.40 5.50 Khanna et al. (2008)
Nonspecific 2 2.18 Mapemba et al.
(2008)
Storage costs were updated by using USDA NASS agricultural-building material prices from 1999-2007
(NASS, 2007a,b).
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TABLE H-5 Estimated Costs of Establishment and Seeding for Cellulosic
Feedstocks
Type of Type of Cost Land Cost per Cost per Reference
Feedstock Rent Acre (cited Acre (2007
Included $) $)
Switchgrass Yes 200 200 Duffy (2007)
Switchgrass No 25.76 46 Perrin et al. (2008)
Yes 85.46 153
PV4 per ton
Switchgrass No 7.21/ton 12.6/ton Khanna et al.
10-year PV per 142.3 249 (2008)
acre
Amortized
4% over 10 17.3 30.25
years
8% over 10 20.7 36.25
years
Switchgrass Yes 72.5-110 88.5-134 Vadas et al. (2008)
Miscanthus PV per ton No 2.29/ton 4/ton Khanna et al.
20-year PV per 261 457 (2008)
acre
Amortized
4% over 20 19 33.2
years
8% over 20 26.20 45.87
years
Miscanthus Total No 1206-2413 Lewandowski
Amortized (2003)
4% over 20 88-175 176-350
years
8% over 20 121-242 242-484
years
Establishment and seeding costs were updated by using USDA NASS agricultural fuel and seed
prices from 1999-2007(NASS, 2007a,b).
4
PV denotes present value
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TABLE H-5 Estimated Opportunity Costs for Cellulosic Feedstocks (Net Returns
Forgone by Producer from Not Using Cropland to Produce Next Best Crop or
Product)
Opportunity Cost5
Type of Type of Cost Cost per Acre Cost per Acre Reference
Feedstock (cited $) (2007 $)
Corn stover Feed value 59.5/ton 59.5/ton Edwards (2007)
2.4 tons/acre 142.8 142.8
Corn stover Lost profits 22-58 22-58 Khanna and
Dhungana (2007)
Switchgrass Lost profits 78-231 78-231 Khanna and
Dhungana (2007)
Switchgrass or Lost profits 78 76 Khanna et al. (2008)
Miscanthus
Miscanthus Lost profits 78-231 78-231 Khanna and
Dhungana (2007)
Lost CRP6
Nonspecific 35 36 Mapemba et al.
payments if (2008)
harvest every
year
Nonspecific Lost CRP if 10.1 10.4 Mapemba et al.
harvest once (2008)
every 3 years
Nonspecific Non-CRP land 10/ton 10.3/ton Mapemba et al.
crops (2008)
Nonspecific 78 76 Khanna et al. (2008)
Woody biomass Alternative use 0-25 Summit Ridge
Investments (2007)
5
Opportunity costs were updated by using USDA NASS agricultural-land rent prices from 1999-2007
(NASS, 2007a,b).
6
CRP stands for Conservation Reserve Program.
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TABLE H-6 Yield Values and Ranges for Different Bioenergy Feedstocks
Reported in Literature
Yield
Biomass Type Assumptions Estimated Yield Reference
(tons/acre)
Corn stover Soil tolerance 2.02 Khanna and Dhungana (2007)
Corn stover 2.4 Edwards (2007)
Corn stover 2000-2005 mean 2.31-3 Vadas et al. (2008)
yields for
Wisconsin
Switchgrass Iowa, Illinois field 2.58 Khanna and Dhungana (2007)
trials
Switchgrass 4 Duffy (2007)
Switchgrass Farm-scale 2.23 (5-year average) Perrin et al. (2008)
(northern South (Range, 1.7-2.7)
Dakota to 3.12 (10-year
southern average)
Nebraska) (Range, 2.6-3.5)
Switchgrass 3.8 Khanna et al. (2008)
19.74 (10-year PV)
Switchgrass Nitrogen level 4-5.8 Vadas et al. (2008)
Switchgrass Research blocks 7.14 (average) Lewandowski et al. (2003)
9.8 (best)
Switchgrass 3.6-8.9 (previous) Shinners et al. (2006)
Plot trials 2.3-4 (own)
Switchgrass Plot trials 6.33 Fike et al. (2006)
4.64-8.5
Switchgrass Field trials Berdahl et al. (2005)
Mean 1.12-4.1
Strains:
Dacotah 1.11-4.22
ND3743 0.91-3.92
Summer 1.18-4.38
Sunburst 1.43-5.57
Trailblazer 1.15-4.88
Shawnee 1.06-4.5
OK NU-2 0.89-4.18
Cave-in-Rock 0.97-4.27
Switchgrass Plot trials Vogel et al. (2002)
Iowa 5.2-5.6
Nebraska 4.7-5
Switchgrass Peer-reviewed 4.46 Heaton et al. (2004a)
articles
Switchgrass Farm trials
Strains:
Alamo (1 cut) 5.4-8.5
Kanlow (1 cut) 5.2-6.9
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Cave-in-rock 6-8.3
(2 cut)
Switchgrass U.S. average 4.2 McLaughlin et al. (2002)
Grasses County-scale in 3.4-4.1 Banowetz et al. (2008)
Pacific Northwest (perennial ryegrass)
4.13-6.2
(tall fescue)
2.2-3.36
(creeping red fescue)
Miscanthus Simulated 8.9 Khanna and Dhungana (2007)
Miscanthus 14.5 average Khanna et al. (2008)
12-17 range
114.58 (20-year PV)
Miscanthus Field experiment 5.71 (14-year) Christian et al. (2008)
3.43-11.73 (3-year)
Miscanthus 4.5-13.4 Lewandowski et al. (2003)
Miscanthus Projection 13.36 (mean) Heaton et al. (2004b)
10.93-17.81
Miscanthus Peer-reviewed 9.8 Heaton et al. (2004a)
articles
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Table H-7 Carbon Inputs to Biomass Production (adapted from Farrell et al.
2006)
Agricultural Phase
Corn Ethanol Cellulosic
(Switchgrass)
Nitrogen-fertilizer emissions 1,638 547
(kg CO2 eq/ha)
Phosphorus (kg CO2 eq/ha) 102 3.4
Potassium (kg CO2 eq /ha) 70 2.4
Lime (kg CO2 eq /ha) 228 -
Herbicide (kg CO2 eq /ha) 69 10.4
Insecticide (kg CO2 eq /ha) 5.4 -
Seed (kg CO2 eq /ha) - -
Transport emissions (kg CO2 39 3
eq /ha)
Gasoline (kg CO2 eq /ha) 114 -
Diesel (kg CO2 eq /ha) 248 341
Natural gas (kg CO2 eq /ha) 46 -
Liquefied petroleum gas (kg 61 -
CO2 eq /ha)
Electricity (kg CO2 eq /ha) 56 42
Energy used in irrigation (kg 4 -
CO2 eq /ha)
Labor transportation (kg CO2 - -
eq /ha)
Farm machinery (kg CO2 eq 21 21
/ha)
CO2 from land-use change - -
(kg/ha)
Total from agricultural 2,703 971
production (kg CO2 eq /ha)
Conversion per acre
(0.405 ha/acre, 2.24 lb/kg) 2,452 lb CO2 eq /ac 881 lb CO2 eq /ac
Conversion per ton
(assume 4 tons/acre) - 220 lb CO2 eq /ton
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Table H-8 Carbon Inputs to Biomass Refining, Including Transportation of
Biomass (adapted from Farrell et al. 2006)
Biorefinery Stage
Corn Ethanol Cellulosic
(Today)
Transport of feedstock to 49 51
biorefinery (g CO2 eq /L)
Primary energy (g CO2 eq - -
/L)
Diesel (g CO2 eq /L) - 5
Coal (g CO2 eq /L) 885 -
Natural gas (g CO2 eq /L) 365 -
Electricity (g CO2 eq /L) - -
Biomass (g CO2 eq /L) - -
Capital (plant, equipment) 8.8 29
(g CO2 eq /L)
Process water (g CO2 eq /L) 25 19
Effluent restoration (BOD at 20 20
PWTPs7) (g CO2 eq /L)
Transportation of - -
chemicals to plant (g
CO2e/L)
Total biorefinery phase (g 1,353 124
CO2e/L)
Coproduct credits (g 525 106
CO2e/L)
Total biorefinery phase 828 g CO2 eq /L 18 g CO2 eq /L
accounting for coproduct
(g CO2 eq /L)
Conversions:
Initial value 828 g CO2 eq /L 18 g CO2 eq /L
[0.4/0.4]/0.38 L/kg ~331.2 g CO2 eq /kg ~6.84 g CO2 eq /kg
~2,896,675 g CO2 eq ~91,998 g CO2 eq /ha
[8746/8389]/13450 kg/ha
/ha ~37,259 g CO2 eq /ac
[26]
~1,173,153 g CO2 eq ~37.3 kg CO2 eq /ac
0.405 ha/acre
/ac
0.001 kg/g
~1,173 kg CO2e/ac
TOTAL 4,307 lb CO2 eq /ac 964 lb CO2 eq /ac
(agriculture phase +
biorefinery)
Conversion per ton:
assume 4 tons/acre - 241 lb CO2 eq /ton
7
BOD at PWTPs stands for biochemical oxygen demand of effluent at waste-water treatment plants
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