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GFP , LLC dba Calgren Renewable GREET Pathway for the Production of Ethanol from Corn and Fueled by NG and from Two Local Dairy Digesters

Date Submitted: September 20, 2018

Location of Ethanol Production Facility: 11704 Road 120 Pixley, California 93256

Period of Analysis:

Twenty four months of data is provided for each of the dairies, and for the ethanol plant. The ethanol plant data includes process invoices and audited reports covering the period July 2016 through June 2018. One of the two dairy digesters has been in operation for over three years; however it was down for repairs from June XX, 20XX to May XX, 20XX. Since the Compliance Offset Protocol for Livestock Projects covers calendar year periods, data is provided for 2015 and 2016, during which period the digester was in continuous operation. The second digester did not begin operation until August XX, 20XX. Historical data for the dairy feeding this digester covers the period September 2016 through August 2018.

Fuel Pathway Information: Feedstock Production Process LCFS Pathway Requested Technology Ethanol Corn Wet DGS, Biogas from Dairy Digesters

Primary Point of Contact: Sarah Gonzales 559-757-3850 ext 2112 [email protected]

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Contents:

Contents 1. Fuel Pathway Summary ...... 3 2. System Boundary ...... 4 3. Result Summary ...... 4 4. Feedstock Phase ...... 5 5. Fuel Phase ...... 6 6. Ethanol Transport and Distribution ...... 6 7. Pathway Inputs ...... 6 8. Life Cycle Results ...... 8 9. Supporting Documents ...... 11

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1. Fuel Pathway Summary

A Well-To-Tank (WTT) fuel cycle analysis of the GFP Ethanol, LLC dba Calgren (Calgren) corn-to- ethanol pathway using biogas from two local dairy digesters as fuel includes all steps from corn farming in the Midwest to ethanol transported to a fuel facility in California. It also includes all steps involved in capturing, transporting, processing and using methane that would otherwise have been released into the atmosphere as a (GHG). Tank-To-Wheel (TTW) analysis includes fuel combustion in a vehicle. Together, WTT and TTW analysis combine to provide a total Well-To-Wheel (WTW) analysis that determines the fuel cycle GHG emissions, also known as carbon intensity (CI), associated with Calgren’s production of fuel ethanol from corn using biogas from the specified dairy digesters as process fuel.

Subsequent fuel pathway applications will follow as each new digester comes on line. New fuel pathway applications will also be filed if substantial portions of biogas are diverted to other uses, such as for renewable (RCNG). All data files accompanying those filings will be updated as appropriate, as will the inputs to the CI calculations.

The first of Calgren’s dairy digesters (Digester #1) is located on site and has been in operation for over three years. However from June XX, 20XX to May XX, 20XX Digester #1 was down for repairs. When in operation Digester #1 is supplied with feedstock manure from XXX (Dairy #1), located about XXX away. Dairy #1 is connected to Calgren’s Pixley production facility via pipelines that are privately owned and maintained. Digester #1 is a concrete plug flow unit designed by DVO, a leader in mesophilic-type, anaerobic dairy digesters (i.e. anaerobic dairy digesters designed to operate at a constant temperature of about 100 degrees Fahrenheit). Biogas from Digester #1 is cleaned sufficiently to allow it to be used as fuel for Calgren’s ethanol process. Specifically, the biogas is used along with natural gas as fuel in the burners located in the exhaust duct of the gas turbine driving electrical generators. These duct burners are immediately upstream of the cogeneration unit’s Heat Recovery Steam Generators and thus allow for the production of supplement steam. The biogas need only be modestly compressed (to XX psi) and modestly cleaned (H2S removed but not CO2) for this use. The electricity consumed by Digester #1 includes manure pumping, compression to XX psi, fiber removal from the digestate, and return pumping of the liquid digestate to Dairy #1 for eventual use as . Electricity attributable to Digester #1 is also used to pump thermal fluid from the exhaust stack of one of the cogeneration units to maintain a constant temperature in Digester #1. This electricity is produced from the combustion of NG in on-site cogeneration turbines and is separately metered and logged. Electricity used by Digester #1 is considered as NG at the GREET 2.0 simple cycle heat rate.

The second dairy digester (Digester #2) is a covered lagoon-type anaerobic unit located at XXX (Dairy #2), about XXX from the biogas cleanup and ethanol facility. Manure flushed from the free-stalls at Dairy #2 enters the lagoon, principally by gravity, where it undergoes anaerobic digestion. A cover over the lagoon captures the resulting biogas, which is comprised of methane, and trace constituents such as sulfide. The biogas is transported via a private, low pressure gas pipeline to a centralized hub at the ethanol facility where it is cleaned up for use as a fuel. Digester #2 operates at ambient temperatures and, unlike Digester #1, there is very little liquid pumping involved. In comparison, the energy required to transport biogas in the low pressure pipeline is modest. Because it recently came on line, unlike for Digester #1 we do not yet have extensive electrical consumption data for Digester #2. However, the energy consumed by Digester #2 is clearly far less than the energy consumed by Digester #1. Thus, until actual energy consumption data is available for Digester #2, we will conservatively assume it is equivalent to Digester #1. We will also conservatively assume all electricity for Digester #2 is supplied by the grid.

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Avoided GHG emissions at the respective dairies in the form of methane are calculated using the Air Resource Board (ARB) Compliance Offset Protocol for Livestock Projects (Livestock Protocol). Pursuant to the Livestock Protocol, baseline methane emissions are calculated using historical cow counts and other dairy operating data. Because of the conservative assumptions underlying the Livestock Protocol, actual methane capture and collection typically exceeds the baseline. The avoided GHG emissions from Digester #1 under the Livestock Protocol have been verified by an independent auditor since 2015. In the course of his/her work, the verifier also confirms the amount of biogas produced. Thus actual, verified data will be used to show the volume of biogas from Digester #1. For Digester #2, 24 months of dairy data is reported herein and the most relevant 12 months is used to calculate the baseline emissions according to the Livestock Protocol. As noted above, actual methane production data will be reported in subsequent fuel pathway code applications. Until at least three months of actual data is available, Calgren will take a conservative approach and assume that biogas volumes from Digester #2 equal the baseline amount of biogas production as modeled for this facility in the Livestock Protocol.

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2. System Boundary

The system boundary for this ethanol fuel pathway code is as follows:

Dairy #1 Digester Digester Dairy #2 Manure #1 #2 Manure

Biogas + Biogas +

Avoided CH4 Avoided CH 4

Cogen Duct NG HRSGs Turbines Burners

SCE Steam Electricity

Airgas CO 2

Raw CO2

EtOH EtOH Use Calgren Ethanol Production Corn Transport as Fuel

WDGS Corn Oil

Credits

Corn /

Figure 1. System Boundary

Calgren’s ethanol production techniques are somewhat unique and inherently efficient. The plant is co-located with two gas-fired, simple-cycle electricity and steam cogeneration units, which add somewhat to that efficiency. As noted previously, there is also an on-site DVO-designed dairy manure digester capable of providing biogas as fuel for the cogeneration units, thus reducing the consumption of NG. The system boundary will be expanded in future applications to include all digesters, including the new ones. As detailed in Appln No. T1N-XXXX, the electricity produced from the gas-fired power plant is distributed between the ethanol plant, the on-site dairy digester, Airgas, and Southern California Edison (SCE).

3. Result Summary

The well-to-tank (WTT) results for ethanol produced at Calgren’s Pixley, CA facility from Midwest corn and utilizing biogas and RNG credits from Digester #1 and Digester #2 are XXX g CO2e/MJ for ethanol on an anhydrous basis.

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These results do not include vehicle methane or N2O emissions, denaturant, or land use conversion (LUC). The full life cycle WTW results for Calgren ethanol are XX.XX g CO2e/MJ.

The direct carbon intensity includes the WTT emissions presented in Table 1. Denaturant and indirect land use change (iLUC) are also shown.

Table 1. Total Carbon Intensity for Calgren Corn Ethanol (g CO22/MJ)

Pathway Feedstock Process RNG T&D Denaturant Indirect Total CI CI Credit LUC Calgren Dry Mill, Wet XX XX XX XX XX XX XX DGS, 2 Dairy Digesters, Balance NG

The net GHG offsets from the respective dairies were calculated using the Livestock Protocol. As noted above, actual biogas production is used for Digester #1. Conservatively, biogas production for Digester #2 is assumed to be equal to the baseline amount of biogas production as modeled for this facility in the Livestock Protocol. The results of the use of the Livestock Protocol are set forth in Table 2.

Table 2. Baseline and project methane emissions from each digester, all values expressed in metric tons (MT) of methane (CH4) per year

Digester Baseline Digester Venting Effluent Storage / Net GHG Biogas Leakage Ponds Treatment Offset Volume Digester #1 XX XX XX XX XX XX XX Digester #2 XX XX XX XX XX XX XX

Each dairy digester was further analyzed by porting the net GHG offsets and the biogas volume from the Livestock Protocol tool into a GREET 2.0 Tier 2 spreadsheet developed and approved by ARB(labeled, respectively, CA GREET 2.0 – RNG Dairy 1 and CA GREET 2.0 – RNG Dairy 2). The spreadsheets convert metric tons of methane into grams of carbon dioxide equivalent using GREET 2.0 parameters. They also adjust for energy consumed in transporting and cleaning up biogas to a usable form of (RNG), including an adjustment for methane not produced in the baseline case but converted to fuel in the project case. Please note that substantial compression is required to make RCNG, while there is relatively little compression involved in using biogas in our duct burners. The results of these calculations are set forth in Table 3. below. Table 3. Carbon intensity of RNG from each dairy digester

Digester Credit for GHG Credit for GHG Biogas RNG Credit for Total avoided avoided Prod., Upgrading diverted CO2 Credit (g expressed as g expressed as g Solids (g CO2e/MJ (g CO2e/MJ of CO2e/MJ CH4/MJ RNG fuel CO2e/MJ RNG fuel Handling (g RNG fuel) of RNG CO2e/MJ) fuel) Digester #1 XX XX XX XX XX XX Digester #2 XX XX XX XX XX XX

Copies of CA GREET 2.0 – RNG Dairy 2 and Dairy 2 are included as exhibits to this application.

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4. Feedstock Phase

Corn farming inputs are those assumed by ARB for the established corn-based ethanol fuel pathways under the LCFS. Corn transportation is by rail from the Midwest, an average of XXXX miles.

5. Fuel Phase

As set forth in more detail in Appln No. T1N-XXXX, a corn ethanol yield of X.XX gal/bu was used. A process flow diagram is provided as part of the attached RFS2 Engineering Report. No grid electricity has ever been used for ethanol processing, so grid electricity input was set at zero. Process energy inputs and outputs are as set forth in the attached energy consumption template, along with chemical and consumption. Both WDGS and corn oil are produced, but no DDGS. Using the historical average WDGS moisture content of XX.X%, the DGS co-product credit corresponds to X.XX dry lb/gal.

6. Ethanol Transport and Distribution

As set forth in additional detail in the previously filed application, there is no rail terminal involved, thus the corresponding distance in the GREET 2.0 calculator was set at zero. Ethanol produced at Calgren’s facility is hauled to the Kinder Morgan terminal in Fresno, a distance of XX miles.

7. Pathway Inputs

The GREET 2.0 input parameters for Calgren’s ethanol production are set forth below in Table 4. With the exception of biogas fuel credits discussed above, the inputs are average values based on monthly data from July 2016 through June 2018. The fossil-based natural gas is arrived at by subtracting the RNG flows discussed above from the historic aggregate.

Table 4. Key Input Parameters for Calgren Ethanol with the CA_GREET model.

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Fuel Yield XX gal/bu Energy Demand Btu/unit of fuel Thermal, DDGS Ethanol 0 Btu/gal (LHV) Thermal, WDGS Ethanol XX Btu/gal (LHV) Biogas XX Btu/gal (LHV) Electricity 0 kWh/gal DDGS 0.0 Bone Dry lb/gal WDGS XX Bone Dry lb/gal Corn Syrup 0.000 Bone Dry lb/gal Corn Oil XX Bone Dry lb/gal Total DGS XX Bone Dry lb/gal Alpha Amylase XX g/gal Gluco Amylase XX g/gal Cellulase 0.00 g/gal XX g/gal (H2SO4) XX g/gal Ammonia (NH3) XX g/gal NaOH 50% XX g/gal CaO 0.00 g/gal Urea XX g/gal

Feedstock Logistics

From collection center to rail/ or to EtOH plant HDD Truck Miles XX From rail/port to California Rail Miles XX Ethanol Logistics

From Bulk Railyard to Fuel Station HDD Truck Miles XX From railyard to CA railyard Rail Miles XX From railyard 80% to blending terminal HDD Truck Miles XX

8. Life Cycle Results

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The life cycle energy and GHG emission results for ethanol produced at Calgren’s plant with two dairy digesters on line are shown below. The calculations were performed using the CA_GREET 2.0 Tier 2 calculator. The complete data set for feedstock, co-product credits, ethanol production, transport and distribution as well as the total WTW emissions are presented in Table 5. The Tier 2 calculator was slightly modified to include the RNG credits as described earlier.

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Table 5. GREET Model Results for Calgren Ethanol Production facility

Corn Ethanol - Dry Mill

Co- Total Corn Different EtOH Different Total Final CI, Farming N O in soil product Feedstock EtOH T&D 2 Transport Process production Process Fuel (g/MJ) Credit (g/MMBtu)

XX XX XX XX XX XX XX XX XX XX VOC XX XX XX XX XX XX XX XX XX XX XX XX XX XX CO XX XX XX XX XX XX XX XX XX XX XX XX

CH4 XX XX XX XX XX XX XX XX XX XX XX XX

N2O XX XX XX XX XX XX XX XX XX XX XX XX

CO2 XX XX XX XX XX XX XX XX XX XX XX XX Convert to gCO2e/MMBtu XX XX XX XX XX XX XX XX XX XX XX XX g/MJ Record Feedstock CI, OK OK OK g/MJ XX Credit Allocation Based Upon Use as RCNG or as EtOH Combined Total All Digesters Process Fuel Fuel CI, g/MJ XX MT MJ RNG Wt. Avg CO2e/yr MJ RNG Credit Production CI Credit Tank-to- Available RNG CI Credit End Use Used (MT) (MJ/Year) per MJ Wheel, g/MJ XX XX XX XX XX XX XX XX XX Denaturant, g/MJ XX

Indirect Land Use, g/MJ XX

RNG Credit, g/MJ XX Individual Digester CIs

CI SCF/year MJ/year XX XX XX Dairy #1 XX XX XX Dairy #2

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9. Supporting Documents

1. Attestation letter (Confidential Information) 2. Energy Consumption (Confidential Information) 3. GREET 2.0 -T2 EtOH Calculator w Dairy 1 (Confidential Information) 4. GREET 2.0 - RNG Dairy 1 (Confidential Information) 5. Livestock Protocol Dairy 1 (each year for 2 years) (Confidential Information) 6. Production Report (Confidential Information) 7. Invoices and Receipts – EtOH Invoices (Confidential Information) 8. Invoices and Receipts – Corn Purchases (Confidential Information) 9. Invoices and Receipts – Chemical Invoices (Confidential Information) 10. Invoices and Receipts – Electricity Invoices (Confidential Information) 11. Invoices and Receipts – Corn Oil Invoices (Confidential Information) 12. Invoices and Receipts – Biogas Invoices (Confidential Information) 13. Other Documents – Chemical Purchases Spreadsheet (Confidential Information) 14. Other Documents – DGS Moisture Reports (Confidential Information) 15. Map showing Fuel Transport Mode to CA (Confidential Information) 16. GPS Coordinates 17. Permit and Operating License 18. Third Party Engineering Report (Confidential Information)

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