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42 C h a p t e r 5 This chapter presents the toolkit developed in conjunction with this guidebook. The toolkit consists of two components: an alternative fuels inventory tracking spreadsheet and a GHG calculator for alternative fuels. 5.1 Inventory Tracking Spreadsheet The first part of the toolkit is an alternative fuels inventory tracking spreadsheet (available on the TRB website). It represents one example of how alternative fuel deliveries may be recorded at an airport fuel facility. It covers the physical delivery of fuel only and can be used to support additional sustainability accounting methods. This design assumes that the alternative fuel is dropped in together with conventional fuel in the receiving tanks (mass-balance, book-and- claim, and hybrid tracking methods). When the alternative fuel is kept physically segregated from the main fuel supply, a separate copy of the spreadsheet can be used and the conventional fuel totals set to zero. A screenshot of the inventory tracking spreadsheet with an illustrative example is shown in Figure 12. The spreadsheet can be used alone or in conjunction with the Spec 123 spreadsheet available from A4A that is widely used by fuel farm operators to track inventory. If using the spreadsheet with Spec 123, copy the total fuel receipts from âtank, receipt, ip tempsâ tab and paste special as values. This total includes all fuel deliveries, conventional and alternative. If any bonded fuel was received, the Spec 123 sheet subtracts the bonded portion from the total automatically. If not using with Spec 123, enter fuel receipts manually. Enter any bonded fuel received (if applicable) and subtract bonded fuel from total receipts. Enter the alternative jet fuel receipts from each provider, including gross and net gallons and blend percentage. Total alternative fuel received and neat gallons equivalent are calculated. Detailed instructions and more information on the tool can be found in the âInstructions and Descriptionâ tab. 5.2 GHG Calculator The second part of the toolkit (available on the TRB website) involves a GHG calculator and rep- resents one example of how sustainability metrics may be tracked. It is intended for use by airport management, but it also may be of use to any other stakeholders in the supply chain. The calculator allows the calculation of information related to the life-cycle greenhouse gas of the airport fuel sup- ply over a given time period. The GHG tool takes information elements from the fuel farm operator and the fuel producer and calculates numbers useful to airport management. From the fuel farm Alternative Fuels Tracking and Greenhouse Gas Tracking Toolkit
alternative Fuels tracking and Greenhouse Gas tracking toolkit 43 operator, the user would receive information on the amount of which alternative fuel was delivered to the fuel farm, the proportion of alternative fuel in each delivery (since most ASTM-approved alternative fuels to date are blends of conventional petroleum fuel and a neat alternative compo- nent), and the producer of each type of alternative fuel delivered. GHG reduction percentages of each fuel compared to conventional Jet A can be found by contacting the fuel producer or the airline buying the fuel. The calculator is not dependent on the CoC method employed for the transfer of sustainability information. The tool is built using constants found from information in the Green- house Gases, Regulated Emissions, and Energy Use in Transportation (GREET) LCA database soft- ware developed by Argonne National Labs, the FAA, and the Energy Information Administration. For any given time period under calculation, the GHG calculator can give the user: â¢ The proportion of alternative jet fuel in the airportâs jet fuel supply as a percentage. â¢ The average GHG emissions intensity of the airportâs jet fuel supply per gallon, labeled as âblended well to wake gCO2/gallonâ in the calculator. This number will be lower the greater the proportion of alternative fuel that is delivered to the airport. â¢ The expected GHG emissions from using the airportâs jet fuel supply (assuming FAA averages for CO2/gallon combusted). â¢ The baseline GHG emissions from using a 100% conventional jet fuel supply. â¢ The reduction in GHG emissions from using the airportâs jet fuel supply versus using a 100% conventional jet fuel. These numbers might be useful to an airport wishing to keep track of its Scope 3 GHG emis- sions related to aircraft fuel. The tool could also be used for scenario planning and estimating amounts of alternative fuel necessary to meet an airportâs GHG reduction goals. The tool presents Figure 12. Alternative fuels tracking spreadsheet.
44 tracking alternative Jet Fuel an option for calculating sustainability metrics that could be included in airport planning and reporting. Airports might use a similar approach to track reductions in criteria pollutants that result from alternative fuel usage once that information becomes more readily available. In order to function, the GHG calculator requires the user to input the blended normal vol- ume of fuel in gallons, the alternative proportion of the fuel delivery as a percentage, and the GHG reduction of the neat alternative fuel compared to conventional fuel for each producer supplying fuel to the airport. An illustrative example is shown in Figure 13. For record-keeping consistency, the user should also select the fuel specification for each kind of fuel being supplied to the airport and the time period under calculation. Consistent and uniform records of fuel deliveries for the time period under calculation are important for the accuracy and usefulness of the GHG calculator. The GHG calculator works in gallons of fuel, grams of CO2 emissions per gallon, and tonnes of CO2 per fuel producer. All estimates of grams of CO2 per megajoule of fuel must be converted to grams of CO2 per gallon before being inputted into the GHG calculator. The calculator assumes that the CO2 emissions due to the combustion stage of the jet fuel life cycle (product to wake) are equivalent for both conventional fuel and alternative fuel. This assumption is made because all ASTM-approved alternative jet fuels (ASTM D7566) are chemi- cally similar enough to be considered drop-in fuels (i.e., interchangeable with conventional fuel; ASTM D1655) in engines and fueling equipment. This assumption may be changed by altering Figure 13. GHG calculator inputs.
alternative Fuels tracking and Greenhouse Gas tracking toolkit 45 Figure 14. GHG calculator outputs. the âJet Fuel Constantsâ tab in the GHG calculator tool Excel file. A screenshot with sample output is shown in Figure 14. It is important to note that for aircraft, CO2 emissions are equivalent to CO2e emissions because CO2 is the only relevant greenhouse gas combustion product according to the FAA Order 1050.1F Desk Reference. The GHG emissions calculator Excel spreadsheet has six tabs: Instructions and Description, Calculator Tool, Example Entries, Jet Fuel Constants, List, and Weights. Detailed instructions and more information on the tool can be found in the âInstructions and Descriptionâ tab.