Biofuels, Solar and Wind as Renewable Energy Systems_Benefits and Risks Episode 2 Part 1 pot

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10 Biomass Fuel Cycle Boundaries and Parameters 237 The second parameter type is the individual parameters (p k ’s and ⌬ k ’s discussed in Section 10.2.2.2) unique to a given module Sub-activity. In the BFCM treatment, Y crop and Y bfp variability relationships are examined separately from the p k values. 10.2.2.1 Biomass Yield Parameters For a given BFC: N crop to bfp = Y crop AY bfp Here N crop to bfp is the BFC net fuel production, Y crop is the agriculture stage biomass crop yield, A is the planted land area, and Y bfp is the biofuel production stage yield. Another BFC general yield and biofuel energy relationship is: E biofuel = N corn to bfp UE fuel e Here E biofuel is the BFC created biofuel energy and UE fuel e is the biofuel useable energy (see Section 10.3). Combining and rearranging these two equations: E biofuel /A = Y crop Y bfp UE biofuel (10.1) E biofuel /A is a measure of the BFC crop and biomass fuel production effi- ciency in creating the biofuel. This equation enables biofuel yield evaluation (see Section 10.4.1) at both the local/regional and national fuel cycle production lev- els. Clearly gains in crop and process yields mean higher biofuel energy per acre planted. 10.2.2.2 Template Parameters For each template Activity, there is an assigned k value. This k value is used to index the p k value assigned to that Activity and it’s associated Sub-activities. The p k value and it’s uncertainty ⌬ k are specific numerical values used in the analysis. Consider, for example, in Template 1 (Table 10.1) under the Facilities Phase there is the Seed Plant Sub-phase. It’s assigned Activity and associated Sub-activities index value is k = 5. Therefore it’s numerical values used in an analysis are assigned to the p 5 and ⌬ 5 parameter in the BFCM equations discussed here (see also Section 10.4.2 for specific illustration) The p k ’s are used to calculate the S module j value of interest: S module j = f j (p k ) and the ⌬ k ’s are used to quantify the uncertainty (⌬ j ) associated with that S module j (see Section 10.2.4). The f j (p k ) equations are typically simple summations for the BFC’s but can be any mathematical relationship. The detail for a given S module j is determined by the BFC scenario and associated module. Both the S module j value and its’ ⌬ j are used to quantifying and characterizing the BFC. 238 T. Gangwer The general relationship applicable to each module is: S BFC = m  j=1 S module j U j F j (10.2) Here S BFC is the total value (e.g., energy, mass, volume) for the given BFC mod- eled scenario made up of m modules; U j is the land area planted, Biorefinery pro- cessed biomass, or biofuel volume; and F j is the scenario specified decimal fraction factor used to evaluate a U j variation (F j = 1ifU j held constant). Sections 10.4.2 and 10.4.3 present the application of this equation to energy and environmental treatments respectively. BFC yields, p k ’s, and ⌬ k ’s values, which are annual numbers, are reported in vari- ous units in the literature. In order to sum the S module j ‘s, the data must be normalize to a common unit. In the current treatment the numerical values are normalized to Btu/Acre. The conversion factors used were: 948.452 Btu/MJ, 0.2520 Kcal/Btu, 3.7854 L/Gal, and 2.471 Acre/Ha. The Biorefinery p k values were normalized to Btu/Acre using each specific study crop and biofuel yields. The resultant S module 3 values are thus a function of these specific yields which introduces two sources of variability into the analysis. 10.2.3 BFC Boundaries A fundamental consideration is the establishment of the given BFC boundaries. As is evident from the results shown in Fig. 10.1, the choice of boundaries can dra- matically change results. It is important to clearly and concisely disposition what is included in and excluded from the BFC. The boundaries for a given BFC are established by using Templates 1, 2, and 3 (see Tables 10.1, 10.2, and 10.3 respectively) as the starting point. The three tem- plates cover a broader range of BFC aspects than typically addressed. Their level of Sub-activity breakout focuses on aspects needing explicate dispositioning. The Sub-activities encompass materials, components, and facilities starting from natural resources through fabrication and usage to disposal. The p k ’s quantify aspects such as raw material extraction (e.g., mining of coal and minerals, petroleum drilling), materials fabrication (e.g., steel, fuel, fertilizer, farm equipment), construction (e.g., facilities, roads), operation (e.g., farming, storage, processing, transporting), and waste management (e.g., discharges, emissions, equipment and facility replaced or decommissioned). The dispositioning (i.e., inclusion or exclusion) of a p k is a boundary decision. The BFC modules enable capturing the justification, including quantification of the impact, of Sub-activity exclusion. However, as evidenced in Fig. 10.1, Sub-activity exclusion can result in important differences between models. Inclusion has the ad- vantages of simplifying the description, facilitating cross model comparison and evaluation, and minimizing the potential for underestimating (which is inherent to BFC’s as a result of their cumulative parameter property). 10 Biomass Fuel Cycle Boundaries and Parameters 239 The energy definitions given in Section 10.3 establish the BFC energy boundaries and accounting of fuel use. Considerations of financial, subsidy, policy, economic, and national security based aspects of a fuel cycle may provide insight into fuel cycle boundaries but should not be used as a basis for disposition because of their introduction of bias. The end result is the BFC Stage Sub-activities and boundary demarcations are clearly delineated and justified. And the p k and ⌬ k values are presented in a standard format. 10.2.4 Statistical Tools Use of statistical tools in the BFCM is intended to facilitate error reduction. Sources of imprecision and uncertainty arise from non-random (determinate) and random (indeterminate) errors resulting from method, measurement, estimation, and/or model decisions. Non-random errors can be difficult to detect. Consistent appli- cation of the BFCM approach provides one tool of use in avoiding and detecting errors. The following statistical tools can be used to reduce random error, evaluate p k and ⌬ k significance, identify p k ’s and ⌬ k ’s whose refinement will improve S module j char- acterization, assessing boundary dispositions, and minimize introduction of bias. The present study assumes the following normal distribution relationships apply (Natrella, 1966; NIST, 2006; Skoog and West, 1963): f(p) = exp {−[(x −m) 2 /2 ␴ 2 ]/[␴(2⌸) 1/2 ]} m = n  i=1 (x i /n) ␴ = standard deviation =   n  i=1 (x i −m) 2  /(n −1)  1/2 v = variance = ␴ 2 Figure 10.1 is obtained by applying the above equations where p equals the indi- vidual NEV values and m is the NEV average value. Curve fitting data (e.g., linear least squares analysis) is readily accomplished using standard computer spreadsheet program functions. One can treat the square of the uncertainty (⌬ 2 i ) associated with each numerical value in a given equation as a variance equivalent and apply absolute and relative deviation addition methods (Skoog and West, 1963) to obtain ⌬ k ‘s and ⌬j‘s. As an example, for the general relationship: ⌬ j = f j (⌬ k ) 240 T. Gangwer the method first treats sums or differences (±)using ⌬ ±equation =  n  k=1 ⌬ k 2  1/2 then multiplications or divisions (x/) using ⌬ x/equation =  n  k=1 (⌬ k /p k ) 2  1/2 as one proceeds from the interior of the function outward. Here n is the number of uncertainty values associated with the numerical values in the f j (⌬ k ) equation. 10.3 BFC Fuel and Net Energy Balance Definitions The BFC energy measure of interest is the Net Energy Balance (NEB): NEB = Total BFC Energy Gain (EG) – Total BFC Energy Loss (EL) = TEG − TEL Concise definition of EG and EL facilitates BFCM bound- ary dispositioning, energy accounting, and consistency. 10.3.1 Fuel Energy Definitions When calculating the NEB, the energy gain (i.e., creation of fuel or productive use of BFC biomass or biofuel) and loss (i.e., consumption/expending of non-BFC fuel or energy) accounting needs to be well defined. The energy independence and environmental national goals lead to replacement of fossil fuels (both foreign and domestic) with domestic biomass fuels. BFC energy accounting needs to address all energy consumptions. The BFC energy definitions that follow directly from the above considerations are: EL = Energy Loss for given BFC = directly (e.g., burned at given BFC fa- cility) or indirectly (e.g., resource extraction/production/refinement, electric- ity generation, steam generation, transport) expended fossil (i.e., petroleum, coal)fuels, biomass/biofuel,electricity, orenergy(e.g., heat)vianuclear/solar/ water/wind power. EG = Energy Gain for given BFC = created biofuels productive combustion (e.g., ethanol fuel oxidant in gasoline, ethanol replacement of gasoline, biodiesel replacement of petroleum diesel) + biomass or BFC created co- products combustion supplying productive heat and/or power (e.g., silage, bagasse) + biomass, biofuels, or coproduct conversion to products (e.g., 10 Biomass Fuel Cycle Boundaries and Parameters 241 biomass digestion resulting in fertilizers, silage composting resulting in lowered field fertilization, conversion of biofuel to pesticides) that dis- place corresponding products derived from fossil (i.e., petroleum, coal) fuel. Note both EL and EG include biomass/biofuel used to supply energy to the given BFC. The inclusion in both is needed in order to have the actual total energy value tabulated for the TEL and TEG. In this way both the TEL and TEG values are comprehensive and unencumbered with BFC specific exceptions/treatments. The accounting of the gain resulting from consumed biomass/biofuel displacing fossil fuel is captured in the EG analysis (see Section 10.3.3). These definitions provide the basis for: excluding through definition the solar energy absorbed in growing the biomass and the caloric energy expended by BFC labor; retention of coproduct energy within the cycle unless some portion of the energy expended to create the coproduct is productively recovered by combustion of the coproduct; treating the use of solid, liquid, or gaseous biomass or biofuel within a given BFC as equivalent to an energy gain (i.e., those biomass fuel consumptions avoid consuming fossil fuels); and treating cogeneration as equivalent to an energy gain (i.e., it avoids consuming fossil fuels). The labor and coproduct aspects are discussed further in Section 10.5. 10.3.2 Fuel Useable Energy The combustion of a fuel can be simplistically viewed as resulting in energy gen- eration, water (as a gas) containing energy in the form of steam heat, combustion products, and particulates. For fossil, biomass, and biofuel fuels, the relevant energy value is the usable energy realized when a quantity of fuel is burned under normal use conditions: UE = Useable Energy = fuel High Heat Value (HHV) adjusted for normal use losses (L). HHV is also referred to as the gross heat content of a fuel. Combustion systems differ in their L value due to inefficiencies (e.g., heat leaks, energy transfer, discharge, friction) and operational variations. For internal combustion engines it is typically assumed the efficiency is the same for all liquid fuels and the main loss is via steam. This L adjusted HHV is commonly referred to as the Low Heat Value (LHV) for the fuel (also called the net heat con- tent) and is commonly used as the UE value. Use of the LHV provides a consistent, common base of comparison. Productive use of L, such as preheater use of boiler system exhaust, increases the UE value with respect to the LHV. For combustion of solid fuels (e.g., crop biomass such as bagasse), the above assumptions and conditions are not applicable. The L value is much more fuel com- position and system efficiency dependent. Capturing BFC energy credit for the use of biomass fuel in place of fossil fuel (e.g., co-generation, pre-heating a process stream) requires consideration of system application specifics. 242 T. Gangwer 10.3.3 Fuel Energy Templates and Analysis When performing the energy EL, EG, and NEB analyses, four templates are used. The Section 10.2.1 Templates 1, 2, and 3 are used to create the BFC specific EL Modules which are then used for the TEL tabulations. The Template 4 given in Table 10.4 is used to create the BFC specific EG Module for the TEG tabulation. In all energy Module tabulations, the applicable UE value should be used. Table 10.4 Template4EnergyGainStage(j= 4) Stage Activity External-to-Given BFC Combustion of BFC Created Fuels: Biofuel, Biomass Combustion of Biomass or coproducts for Heat and/or Power Fossil feedstock based products Displacement by Biomass, Biofuel, or coproduct Infrastructure Manufacture Operations Fuels: Biofuel, Biomass Facilities Operations Fuels: Biofuel, Biomass Agriculture Operations Fuels: Biofuel, Biomass Biofuel Production Biorefinery Plant Operations Fuels: Biofuel, Biomass Fuel Handling Facility Operation Fuels: Biofuel, Biomass Applying the equation 10.2 relationship to the Modules, where we hold U con- stant, define S module j = E module j , and calculate the EL’s and EG’s on a per unit area basis, gives the general BFCM equations: TEL BFC = q  j=1 E module j TEG BFC = 1  j=1 E module j Here E module j is the template derived assessment for module j of the EL or EG value and q and l are the number of module values that form the basis for the cited value. Section 10.4.2 presents the NEB analysis for several BFC’s. 10.4 BFC Models The following application of the BFCM to energy and environmental scenario mod- els uses representative as opposed to all inclusive literature data. The purpose is to illustrate the use of the methodology for a few BFC data sets. In the present treatment, the parameters of interest are specified using British thermal unit (Btu), Acre, Gallon (Gal), and Bushel (Bu) units. 10 Biomass Fuel Cycle Boundaries and Parameters 243 10.4.1 Analyzing Yield Aspects The two main BFC liquid biofuels products are ethanol (e) and biodiesel (d). Con- sider the created ethanol fuel energy per acre for the corn to ethanol BFC where the portion F of corn processed through the wet versus dry milling is varied. Based on equation 10.1 the energy-yield relationship is: E e /A(Btu/Acre) = Y C [Y D F +Y W (1 −F)]E biofuel e Here Y D is the Y bfp for corn to ethanol Dry mill processing, Y W is the Y bfp for corn to ethanol Wet mill processing, F is the fraction of ethanol corn Dry mill processed, and E biofuel e is the ethanol UE fuel value. Figure 10.2 shows the E e /A linear least square fit results for some corn and ethanol production yields. From a local/regional and national perspective, the potential gain from BFC improvement is an important consideration. The equation 10.1 E e /A yield relation- ship provides insight into such considerations. Large variations in corn yields oc- cur as the result of soil, weather, and crop management practices: 85–245 Bu/Acre (Dobermann and Shapiro, 2004). For biorefinery yields in the 2.6 Gal/Bu range, a region producing at 140 Bu/Acre will attain E e /A values 25% higher than a region E e / A as a Function of Mill Mix and Mill Yield 1.50E+07 2.00E+07 2.50E+07 3.00E+07 3.50E+07 4.00E+07 4.50E+07 5.00E+07 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 F (Corn to Ethanol Mill Yield Mix) E e / A (Btu/Acre) Y Mill = 2.0 Gal/Bu Y Mill = 3.0 Gal/Bu Y C = 200 (Bu/Acre) E e /A = 1.51E+07 x F + 3.03E+07 Y C = 100 (Bu/Acre) E e /A = 7.57E+06 x F + 1.51E+07 Y C = 150 (Bu/Acre) E e /A = 1.14E+07 x F + 2.27E+07 Y C = 140 (Bu/Acre) E e /A = 1.06E+07 x F + 2.12E+07 E biofuel e = 7.57E+4 Btu/Gal Fig. 10.2 BFC created ethanol fuel energy per acre as a function of crop yields and corn to ethanol mill processing yields 244 T. Gangwer producing 112 Bu/Acre. Alternatively, processing the 112Bu/Acre region corn at a 2.8 Gal/Bu biorefinery achieves 8% higher E e /A value over the 2.6 Gal/Bu facil- ity. A subset of this is Wet versus Dry mill utilization considerations illustrated in Figure 10.2. The BFCM facilitates such local/regional Y C and Y bfp coupled evalua- tions which may be of value to National energy considerations. For the soybean to biodiesel BFC the created biodiesel energy per acre is: E d /A(Btu/Acre) = Y S Y d E biofuel d Combining the corn and soybean crop rotation and fuel production BFC’s: E ed /A(Btu/Acre) = Y C CR [Y D F +Y W (1 −F)] E fuel e +Y S (1 −CR) Y d E fuel d Here E ed /A is the combined energy content of ethanol and biodiesel fuel produced and CR is the crop rotation cycle fraction for corn planting (e.g., alternating plant- ings: CR = 0.5; 2 out of every 3 plantings: CR = 0.67). Figure 10.3 shows some of the possible correlation plots. For current yield conditions, annual crop rotation gives an E ed /Aof1.73 ×10 +7 Btu/Acre while corn only (i.e., no rotation) gives 5.50 × 10 +7 Btu/Acre for the comparable 2 year period. Examination of the left (100% soybean) and right (100% corn) axes shows optimization of the corn to ethanol parameters holds the greater promise for improving biofuel production efficiency, despite E biofuel d being 1.55 times E biofuel e . However, this result does not address the NEB aspects (Section 10.4.2). Nor does it factor in the need for conser- vation measures to deal with such aspects as soil depletion, crop diseases, and crop pests. The CR needed to achieve an equal energy gain from each crop in the corn- soybean BFC is given by the relationship: CR = Y S Y d E fuel d /[Y C Y Mill E fuel e +Y S Y d E fuel d ] Here [Y D P+Y W (1−P)] is defined as the corn to ethanol effective processing yield Y Mill . To achieve parity under the ‘current yields’ (Fig. 10.3) requires a 5 plantings crop rotation sequence comprised of 1 corn planting for every 4 soybean plantings. The alternate year crop rotation sequence approaches parity for the low corn and high soybean yields. Again the analysis does not include NEB aspects. 10.4.2 BFC Energy Scenario Models and Analysis The structure of the energy relationships follows directly from the associated mod- ular configuration of the BFC scenario. Templates 1, 2, and 3 (Section 10.2.1) were used to construct the Modules 1 – 9 EL tabulations given in Tables 10.5–10.13. Template 4 (Section 10.3.3) was used to construct the EG Modules 100–102 given in Tables 10.14–10.16. Each Module lists the Sub-activity k assignment (see 10 Biomass Fuel Cycle Boundaries and Parameters 245 E ed /A as a Function of Corn-Soybean Crop Rotation Y S = 40.0, Y d = 1.50 E ed /A = 4.19E + 13 x CR + 3.63E + 13 Current corn & soybean: Y C = 140, Y e = 2.60, Y S = 40.0, Y d = 1.50 E ed /A = 1.06E + 14 x CR + 3.63E + 13 Current corn & high soybean: Y C = 140, Y e = 2.60 Y S = 50.0, Y d = 2.00 E ed /A = 8.18E + 13 x CR + 6.05E + 13 Current corn & low soybean: Y C = 140, Y e = 2.60, Y S = 30.0, Y d = 2.00 E ed /A = 1.24E + 14 x CR + 1.81E + 13 High corn & current soybean: Y C = 200, Y e = 3.00, Y S = 40.0, Y d = 1.50 E ed /A = 1.98E + 14 x CR + 3.63E+13 1.00E+06 6.00E+06 1.10E+07 1.60E+07 2.10E+07 2.60E+07 3.10E+07 3.60E+07 4.10E+07 4.60E+07 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 CR (Crop Rotation) E ed /A (Btu/yr) Low corn & current soybean: Y C = 100, Y e = 2.0 E biofuel e = 7.57E + 4 Btu/Gal E biofuel d = 1.17E + 5 Btu/Gal Fig. 10.3 BFC created ethanol-biodiesel fuel energy per acre as a function of yields and crop rotation Section 10.2.2.2) and the number of literature data points used to obtain p k , along with the available ⌬ k values. Based on Section 10.3.3, the NEB equation is: NEB BFC = TEG BFC −TEL BFC = 1  i=1 EG i − q  i=1 EL i The l and q values are established by the modeled scenario. Table 10.17 lists the BFC module E module j relationships which were used to obtain the Table 10.18 BFC scenarios. 246 T. Gangwer Table 10.5 Module 1 Infrastructure for Corn energy loss EL data (EBAMM, 2007) in Btu/Acre (j = 1) Phase Sub-phase Activity Sub-activity k ∗ n a ∗ p k ∗ ⌬ k ∗ Tractors, Combines, Trucks, Manufacture Equipment Fabricate Implements 1 3 1.36 ×10 +6 1.13 ×10 +6 Irrigation, Treatment (water, waste) Facilities Seed Plant Physical Plant Operations/ fuel 524.66 ×10 +5 3.89 ×10 +5 Fertilizer Plant Physical Plant Operations/ fuel 6233.69 ×10 +6 3.43 ×10 +5 Herbicide Plant Physical Plant Operations/ fuel 774.07 ×10 +5 2.63 ×10 +5 Insecticide Plant Physical Plant Operations/ fuel 871.09 ×10 +5 1.55 ×10 +5 Lime Facility Physical Plant Operations/ fuel 952.13 ×10 +5 1.80 ×10 +5 Biorefinery Physical Plant Construct 10 1 1.65 × 10 +5 nv Offsite Water Treatment Plant Treatment of: Water or Wastewater Operations/fuel 12 1 3.57 ×10 +5 nv Total EL IC & ⌬ ⌬ ⌬ IC :6.77 ×10 +6 1.29 ×10 +6 ∗ With respect to k, n, p k ,and⌬ k , see Section 10.2.2.2 for definitions and Section 10.2.4 for detailed illustration on usage in calculations. a values obtained by using only non-duplicated data from cited reference nv: no value The following illustrates the BFCM module notation and analysis. First consider the Seed Plant Sub-phase in Module 1 (j = 1) shown in Table 10.5. It’s k = 5 indexed Activity: ‘Physical Plant’ and associated Sub-activity: ‘Operations/fuel’ p 5 and ⌬ 5 values are based on two literature values. This is captured by the n = 2 designation in Module 1. In terms of the Section 10.2.2.2 equation: S module j = f j (p k ) we have for Module 1: S module j = E module 1 = f 1 (p k ) ≡ EL IC where the f 1 (p k )isasummationof8p k terms (t = 8): EL IC = f 1 (p k ) = 8  t=1 p k,t [...]... grown; (1 – CR) = fraction of full crop rotation schedule that soybean is grown Disposition Overall 10 0 1 2 3 1 2 3 10 1 4 5 6 1 02 7 8 9 1 9 18 2 9 18 2 1 7 17 2 2 7 12 1 8 70 27 14 70 27 14 8 70 27 18 8 70 27 18 10 0 10 1 1 2 3 4 5 6 1 1 9 18 2 7 17 2 8 8 70 27 14 70 27 18 b NEB Equation & Value ±⌬ NEBCe = EGCe − ELIC − ELC − ELCe = 2. 8 ± 3.8 × 10 +6 Btu/Acre NEBSd = EGSd − ELIS −ELS −ELSd = 1. 4 × 10 +6... and Parameters 25 5 Table 10 .19 Greenhouse gas emission (GGE) data in g CO2e /Gal (EBAMM, 20 07) Stage Infrastructure Agriculture Biofuel Production j k 1 10 2 3 3 1 3 2 Net Greenhouse Gas Emission: na GGEjk b ⌬ (GGEjk )b Number of quantified GGEjk values 2 14 13 1 48 7.55 × 10 +0 3.33 × 10 +3 7.84 × 10 +2 1. 12 × 10 +2 4 .23 × 10 +3 nv 6 .29 × 10 +2 1. 06 × 10 +2 nv 6.38 × 10 +2 1 out of 12 1 out of 1 2 out of 2. .. treatment k∗ n∗ pk ∗ 1 1 5 1 ⌬k ∗ +6 2. 27 × 10 nv 1 .23 × 10 +5 nv Total ELSd & ⌬Sd : 2. 39 × 10 +6 nv ∗ With respect to k, n, pk , and ⌬k , see Section 10 .2. 2 .2 for definitions and Section 10 .2. 4 for detailed illustration on usage in calculations nv: no value 25 0 T Gangwer Table 10 .11 Module 7 Infrastructure for Switch Grass energy loss EL data (EBAMM, 20 07) in Btu/Acre (j = 1) Phase Sub-phase Activity k∗ na∗.. .10 Biomass Fuel Cycle Boundaries and Parameters 24 7 Table 10 .6 Module 2 Corn Agriculture energy loss EL data (EBAMM, 20 07) in Btu/Acre (j = 2) ∗ Phase Sub-phase Activity Sub-activity k∗ na p∗ k Land Growing Transport to Farm Seeds Equipment Labor Fertilizer Lime Herbicide Insecticide 1 1 1 1 1 1 1 7 1 In Equipment value 1. 66 × 10 +5 9.54 × 10 +4 1. 11 × 10 +5 nv In Equipment value... ⌬∗ k 1 1 5.78 × 10 +5 nv 5 1 8.90 × 10 +5 nv Operations/fuel 6 3 4 .22 × 10 +5 nv Operations/fuel 7 1 2. 09 × 10 +5 nv Operations/fuel 9 1 2. 17 × 10 +6 nv Construct 10 3 3.93 × 10 +5 nv Total ELIS & ⌬IS : Phase 4.66 × 10 +6 nv Sub-activity Tractors, Combines, Trucks, Implements Irrigation, Treatment (water, waste) Operations/fuel With respect to k, n, pk , and ⌬k , see Section 10 .2. 2 .2 for definitions and Section... waste) Operations/fuel Operations/fuel Physical Plant Physical Plant Treatment of: Water or Wastewater Seed Plant Fertilizer Plant Herbicide Plant Biorefinery Offsite Water Treatment Plant ⌬∗ k 1 2 5.07 × 10 +5 5.44 × 10 +5 5 2 6 5 1. 89 × 10 +5 nv 1. 75 × 10 +6 1. 08 × 10 +6 Operations/fuel 7 2 2.67 × 10 +5 3.04 × 10 +5 Construct Operations/fuel 10 1 12 1 8.67 × 10 +5 nv 5. 72 × 10 +5 nv Total ELISG & ⌬ISG : 4 .15 ... Tilling 1 1 1 1 3 2. 20 × 10 +5 2. 60 × 10 +5 In Tilling value 33 3.03 × 10 +6 Field Fertilizer Line Herbicide Insecticide 1 1 1 1 Crop and Silage Processing Operations/fuel 2 Transport: 2 Storage, Biorefinery Facilities & Other Equipment Operations/fuel 3 Harvest General Full crop Items Cycle ⌬∗ k 9. 42 × 10 +5 In Tilling value 6 In Tilling value 1. 35 × 10 +6 1. 15 × 10 +6 Total ELC & ⌬C : In Tilling value 4.88 × 10 +6... 3. 025 × 10 +7 Btu/Acre TELCe = i =1 24 8 T Gangwer Table 10 .7 Module 3 Corn to ethanol Production EL data (EBAMM, 20 07) in Btu/Acre (j = 3) Phase Subphase Activity Biorefinery Plant Production Processing to 99.5% Ethanol K∗ Sub-activity ∗ pk ∗ na Operations/fuel 1 12 Transport of 1 1 chemicals to Plant Process water 1 1 treatment Total ELCe & ⌬Ce : ⌬k ∗ 1. 64 × 10 +7 1. 82 × 10 +6 2. 63 × 10 +6 nv 3.93 × 10 +5... Tilling value 1. 59 × 10 +6 4.83 × 10 +5 In Tilling value 3 .27 × 10 +6 4.83 × 10 +5 With respect to k, n, pk , and ⌬k , see Section 10 .2. 2 .2 for definitions and Section 10 .2. 4 for detailed illustration on usage in calculations a values obtained by using only non-duplicated data from cited reference nv: no value 10 Biomass Fuel Cycle Boundaries and Parameters 25 1 Table 10 .13 Module 9 Switch Grass to ethanol... 20 07b) 25 4 T Gangwer NEB Corn-Soybean Crop Rotation BFC 1. 00E+06 1 .20 E+06 1. 40E+06 NEB = 1. 61E + 06 x CR – 1. 41E + 06 NEB (Btu/Acre) 1. 60E+06 1. 80E+06 2. 00E+06 2. 20E+06 2. 40E+06 2. 60E+06 2. 80E+06 –3.00E+06 0 0 .1 Soybean Only 0 .2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Crop Rotation (CR) 1 Corn Only Fig 10 .4 Corn to Ethanol Plus Soybean to Biofuel BFC NEB Dependence on Crop Rotation (CR) Consider the potential . GGE jk values Infrastructure 1 10 2 7.55 10 +0 nv 1 out of 12 Agriculture 2 3 14 3.33 10 +3 6 .29 10 +2 1 out of 1 Biofuel Production 3 1 13 7.84 × 10 +2 1. 06 10 +2 2 out of 2 32 1 1. 12 10 +2 nv Net. Wet milling: E Ce = E DCe +E WCe 10 0 1 8 NEB Ce = EG Ce −EL IC − EL C − EL Ce = 2. 8 ±3.8 × 10 +6 Btu/Acre 19 70 21 827 3 21 4 19 70 21 827 3 21 4 Soybean to Diesel Soybean only 10 1 1 8 NEB Sd = EG Sd − EL IS −EL S −EL Sd = 1. 4 10 +6 Btu/Acre 4770 51 727 6 21 8 SwitchGrass to. value Equipment 1 7 1. 66 10 +5 9.54 10 +4 Labor 1 1 1. 11 10 +5 nv Fertilizer 1 In Equipment value Lime 1 Herbicide 1 Insecticide 1 Irrigation system & water Operations/fuel 1 3 2. 20 10 +5 2. 60 10 +5 Pre-planting

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