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How Can Alternative Jet Fuels Be Integrated into the Airport Setting? 37 Federal and state government programs: The federal government and many states offer incentives for the development of alternative fuels. The Department of Commerce keeps a list of those programs that could apply to alternative jet fuel or avgas projects (DOC 2011). The Department of Energy maintains a full list of incentives for all sorts of alternative fuel pro- grams as well as a map of existing demonstrator programs (DOE 2011b). The final rules for implementing the August 2011 three-agency initiative should be consulted. These rules are expected to specify how co-investments in projects by other public- and private-sector entities will be evaluated, making these rules particularly important. Possible price supports for growers and price collars for buyers and sellers, similar to those available for food crops (USDA 2010a). Department of Defense (DOD) policies involving alternative fuel commitments such as the plan to have 50% of continental U.S. military jet fuel consumption sourced from synthetic fuels blends (Andrews 2009). Tax credits such as the one-dollar-per-gallon tax credit for biofuels (currently renewed on a year-by-year basis) (American Fuels 2010). Energy policy: How can the energy policy elements of an alternative jet fuel project be evaluated? "Worksheet 3: Energy Policy Considerations" in Section 5.2.3 can be used to evaluate energy policy elements and corresponding sources of support. After checking the appropriate boxes in the worksheet, the following evaluation guide is recommended for grading the different options: Green: All or most policies are applicable. (Most or all boxes checked are in the "Applicable" column.) Yellow: Some policies are applicable and most may be applicable. (Some boxes checked are in the "Applicable" column, most boxes checked are in "May Be Applicable" column, and some boxes checked are in "Not Applicable" column.) Red: No policies are applicable. (Most boxes checked are in "Not Applicable" column.) After completing the grading, fill in the appropriate circle in the "Green," "Yellow," or "Red" column in the "Energy policy" row of "Worksheet 6: Evaluation Summary" in Section 5.2.6. Note: This evaluation is intended to reflect the possible strength of support from a number of entities and their policies on alternative jet fuels for individual project options. A grading of red does not mean that a project is not viable. Such a grading would only indicate that the project does not appear to benefit from the potential support of the entities listed in the worksheet. This may put a given project at a disadvantage compared to other projects that may get a higher grade in energy policy considerations. 3.5.2 Environmental As discussed in Section 2.4, alternative jet fuels have two principal potential environmental benefits. First, the overall life-cycle GHG footprint may be lower than for conventional fuel. Sec- ond, particulate emissions such as PM2.5 may be lower. Reductions in NOx have been docu- mented for alternative ground fuels (relative to diesel fuel), but there is no current evidence to suggest that the same benefit extends to alternative jet fuels. Information on how to evaluate the GHG and particulate matter benefits of alternative jet fuel options is presented in the following. How should the life-cycle GHG footprint of alternative jet fuels be determined? As discussed in Sections 2.4 and E.1, the life-cycle GHG footprint of alternative jet fuels should be determined with a suitable LCA methodology. To date, there is no one methodology that is universally accepted; however, materials produced by the Department of Defense (Allen et al. 2009) and PARTNER (Stratton, Wong, and Hileman 2010) offer sufficient guidance and are

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38 Guidelines for Integrating Alternative Jet Fuel into the Airport Setting recommended for a first-order analysis. Consultation with outside experts is recommended for a more in-depth study. In terms of targets for desired life-cycle GHG footprints of alternative jet fuels, the airport should be aware of the needs of potential users and set reasonable expectations. The development of alternative jet fuel will be incremental. As technologies develop and feedstocks mature, it is expected that the life-cycle GHG footprint of these fuels will improve. Thus, supporting produc- tion of alternative jet fuels that achieve even only modest reductions in the near term is important to spur development of fuels achieving larger reductions in the future. What questions should be considered in this part of the evaluation? Questions that should be considered in this part of the evaluation are as follows: 1. What is the estimated life-cycle GHG footprint of the alternative jet fuels being considered in the option? 2. What is the overall net footprint of the blend of alternative jet fuel and conventional fuel, given that alternative jet fuels have only been certified as blends? 3. What is the range of uncertainty in the answers to (1) and (2)? These questions should be answered with the latest available official estimates of life-cycle GHG footprints. As mentioned previously, it is recommended that outside experts be engaged to conduct this analysis since there is still no one methodology that is universally accepted. A sample calculation is as follows: Alternative fuel: Coal and switchgrass to FT fuel, with CCS Estimated life-cycle GHG footprint: 53.056.9 g CO2e/MJ, relative to 87.5 g CO2e/MJ for con- ventional petroleum-based jet fuel (data from Table 4 in Section 5.1). (Where g CO2e is grams CO2 equivalent; MJ is megajoules.) Estimated mix of alternative and conventional fuels: 50/50 Resulting overall footprint of fuel mix, relative to 100% conventional case: relative footprint (low) = [(0.5 53.0) + (0.5 87.5)] / (1.0 87.5) = 70.25 / 87.5 = 0.80 relative footprint (high) = [(0.5 56.9) + (0.5 87.5)] / (1.0 87.5) = 72.20 / 87.5 = 0.83 Thus, the proposed alternative fuel at the proposed level of mixture with conventional jet fuel is estimated to reduce the overall life-cycle GHG footprint of the fuel being used by between 17% and 20%. How can the life-cycle GHG footprint of alternative jet fuels be evaluated? The net environmental evaluation of the relative life-cycle GHG effects may be done using the following rating: Green--Use this rating if the alternative jet fuel is likely to achieve life-cycle GHG reductions. Yellow--Use this rating if the alternative jet fuel may achieve life-cycle GHG reductions. Red--Use this rating if the alternative jet fuel is not likely to achieve life-cycle GHG reductions. After completing the grading, fill in the appropriate circle in the "Green," "Yellow," or "Red" column in the "Life-cycle GHG" row of "Worksheet 6: Evaluation Summary" in Section 5.2.6. How should the local air quality benefits of alternative jet fuels be determined? As with life-cycle GHG, outside experts should be consulted to perform a detailed calculation of PM2.5 benefits. A simple methodology is presented in the following to perform a first-order approximation estimate.