Securing Foreign Oil: A Case for Including Military Operations in the Climate Change Impact of Fuels

Military operations are major industrial activities that use massive amounts of fuel and materials that significantly contribute to climate change. In this article, we assert that military activity to protect international oil trade is a direct production component for importing foreign oil— as necessary for imports as are pipelines and supertankers—and therefore the greenhouse gas (GHG) emissions from that military activity are relevant to U.S. fuel policies related to climate change. Military security for protection of global maritime petroleum distribution is part of the acquisition process, but in addition, recent Middle Eastern wars may also be related to securing petroleum reserves. A component of U.S. motor fuel policy has been to encourage the development of biofuels as substitutes for petroleum, both to reduce dependence on foreign oil and to reduce GHG emissions. To qualify for this substitution under the U.S. Energy Independence and Security Act of 2007 (EISA), specific biofuel types must reduce GHG emissions by set amounts from 20 to 60 percent compared with gasoline. The EISA legislation demands evaluation of not only direct life cycle emissions from biofuels, but also all potentially significant indirect emissions. Yet the gasoline emissions against which this is compared consist only of direct life cycle emissions, which to this point have not included emissions due to the military component of transporting foreign oil to the United States. These military emissions are analyzed here to determine their contribution to the life cycle GHG emissions from gasoline production. This analysis builds on a recent estimate that emissions from military security raised the GHG intensity of U.S. gasoline derived from Middle Eastern imports by twofold compared with direct emissions

Indirect Land Use Emissions in the Life Cycle of Biofuels: Regulations vs. Science

Recent legislative mandates have been enacted at state and federal levels with the purpose of reducing life cycle greenhouse gas (GHG) emissions from transportation fuels. This legislation encourages the substitution of fossil fuels with “low-carbon” fuels. The burden is put on regulatory agencies to determine the GHG-intensity of various fuels, and those agencies naturally look to science for guidance. Even though much progress has been made in determining the direct life cycle emissions from the production of biofuels, the science underpinning the estimation of potentially significant emissions from indirect land use change (ILUC) is in its infancy. As legislation requires inclusion of ILUC emissions in the biofuel life cycle, regulators are in a quandary over accurate implementation. In this article, we review these circumstances and offer some suggestions for how to proceed with the science of indirect effects and regulation in the face of uncertain science. Besides investigating indirect deforestation and grassland conversion alone, a more comprehensive assessment of the total GHG emissions implications of substituting biofuels for petroleum needs to be completed before indirect effects can be accurately determined. This review finds that indirect emissions from livestock and military security are particularly important, and deserve further research

Securing Foreign Oil: A Case for Including Military Operations in the Climate Change Impact of Fuels

Military operations are major industrial activities that use massive amounts of fuel and materials that significantly contribute to climate change. In this article, we assert that military activity to protect international oil trade is a direct production component for importing foreign oil— as necessary for imports as are pipelines and supertankers—and therefore the greenhouse gas (GHG) emissions from that military activity are relevant to U.S. fuel policies related to climate change. Military security for protection of global maritime petroleum distribution is part of the acquisition process, but in addition, recent Middle Eastern wars may also be related to securing petroleum reserves. A component of U.S. motor fuel policy has been to encourage the development of biofuels as substitutes for petroleum, both to reduce dependence on foreign oil and to reduce GHG emissions. To qualify for this substitution under the U.S. Energy Independence and Security Act of 2007 (EISA), specific biofuel types must reduce GHG emissions by set amounts from 20 to 60 percent compared with gasoline. The EISA legislation demands evaluation of not only direct life cycle emissions from biofuels, but also all potentially significant indirect emissions. Yet the gasoline emissions against which this is compared consist only of direct life cycle emissions, which to this point have not included emissions due to the military component of transporting foreign oil to the United States. These military emissions are analyzed here to determine their contribution to the life cycle GHG emissions from gasoline production. This analysis builds on a recent estimate that emissions from military security raised the GHG intensity of U.S. gasoline derived from Middle Eastern imports by twofold compared with direct emissions

Opportunities for Nebraska in Future Carbon Markets: Final Technical Report for NCESR Project 3-#303

This study was funded to explore potential opportunities for Nebraska in future carbon markets, most explicitly those opportunities related to the possibility of replacing fossil fuels with biomass at Nebraska corn ethanol plants. The most direct and significant finding is that biomass-fired CHP (combined heat and power) technology is not economically viable for Nebraska corn ethanol plants under current conditions. We estimate in the study that corn stover price would have to be at least $50 per ton of dry matter for the requisite amounts to be delivered to any of the three ethanol plant locations considered (Adams, Norfolk and Wood River). At this price, adoption of CHP would reduce ethanol plant fuel expenditures from about$0.16 per gallon for fossil fuels to about $0.10 per gallon for corn stover, and in addition could add nearly$0.04 per gallon in receipts from sale of surplus electricity to the grid, for a net operating cost reduction of about $0.095 per gallon. However, retrofitting a plant for CHP would require large capital investments with an amortized cost of about$0.24 per gallon, substantially greater than the fuel savings. Potential carbon markets could add only marginal improvements to the prospects for CHP feasibility, adding revenues of about $0.02 per gallon from carbon offsets and perhaps another$0.014 from renewable energy credits. This would bring net operating cost savings to about $0.13 per gallon, still far from paying for the$0.24 per gallon capital cost. CHP technology could become feasible if the capital cost for retrofitting a plant were to fall by 50%, or if natural gas and electricity prices were to rise considerably - at least 60% relative to 2009 prices. Another consideration is the impact of BCAP, USDA\u27s Biomass Crop Assistance Program. This program offers producers a matching payment for whatever price they receive for biomass from an authorized biomass-using facility. The practical effect of this would be to cut in half the price that biomass facilities must pay for delivered biomass, except that the matching payments are limited to two years. Ethanol plants would not be able to invest the capital for retrofitting to biomass based on lower prices for biomass that are limited to only two years, so BCAP will have little impact on CHP feasibility. It is possible that CHP-based ethanol could have a higher market value because of a lower carbon footprint, in California or states that adopt similar policies. We have not made an estimate of this value, because current California regulations do not include soil carbon losses within the boundary of the LCA (life cycle analysis) for the carbon content of biofuels. Our estimates are that conversion to stover-fired CHP would reduce the GHG intensity of the ethanol by 13.3 gCO2e MJ-1. However, the reduction of Midwest corn ethanol\u27s footprint by that amount would provide a fuel with a GHG reduction of only 11% relative to gasoline, which would result in a minimal carbon premium in California even if their regulations were changed to recognize it. An important contribution of this project has been the estimation of supply curves for various amounts of corn stover or switchgrass to be delivered at one of the three delivery points in the study. Biomass in large quantities may be used for other purposes, such as for co-firing with coal in electrical generating plants, or as a feedstock for cellulosic ethanol. The relationship between delivered price and quantity is important information in the evaluation of any such project. One significant finding of the study is that corn stover price would need to be at least $50 per ton of dry matter to have small amounts of less than 100,000 tons per year delivered, or$55-$62 per ton to have a million tons per year delivered, depending on the location in Nebraska. A second significant finding is the lack of competitiveness of switchgrass as a source of biomass in the area of the study. Given current switchgrass technology, prices would have to be$70-$75 per ton of dry matter for delivery of 100,000 to one million tons per year. The project conducted several background studies to be able to address the above issues, results of which are summarized in the report. We reviewed the history and status of climate change initiatives in the U.S. and internationally, from which we were able to identify carbon credits as possible benefits in the future, and renewable energy credits and BCAP benefits available currently and the near future. We also reviewed and summarized the literature on ethanol\u27s carbon footprint attributable to Indirect Land Use Change (ILUC), and though we did not attempt any original research on this issue, a thesis study was in progress at the close of the project examining the potential effects of corn stover revenues on the expansion of cropland into pasture and hay lands in Nebraska. Finally, we examined the relationships between prices of energy sources in Nebraska (natural gas, electricity, and diesel) to aid in understanding how changing energy prices would affect financial feasibility of retrofitting to CHP

Opportunities for Nebraska in Future Carbon Markets: Final Technical Report for NCESR Project 3-#303

This study was funded to explore potential opportunities for Nebraska in future carbon markets, most explicitly those opportunities related to the possibility of replacing fossil fuels with biomass at Nebraska corn ethanol plants. The most direct and significant finding is that biomass-fired CHP (combined heat and power) technology is not economically viable for Nebraska corn ethanol plants under current conditions. We estimate in the study that corn stover price would have to be at least $50 per ton of dry matter for the requisite amounts to be delivered to any of the three ethanol plant locations considered (Adams, Norfolk and Wood River). At this price, adoption of CHP would reduce ethanol plant fuel expenditures from about$0.16 per gallon for fossil fuels to about $0.10 per gallon for corn stover, and in addition could add nearly$0.04 per gallon in receipts from sale of surplus electricity to the grid, for a net operating cost reduction of about $0.095 per gallon. However, retrofitting a plant for CHP would require large capital investments with an amortized cost of about$0.24 per gallon, substantially greater than the fuel savings. Potential carbon markets could add only marginal improvements to the prospects for CHP feasibility, adding revenues of about $0.02 per gallon from carbon offsets and perhaps another$0.014 from renewable energy credits. This would bring net operating cost savings to about $0.13 per gallon, still far from paying for the$0.24 per gallon capital cost. CHP technology could become feasible if the capital cost for retrofitting a plant were to fall by 50%, or if natural gas and electricity prices were to rise considerably - at least 60% relative to 2009 prices. Another consideration is the impact of BCAP, USDA\u27s Biomass Crop Assistance Program. This program offers producers a matching payment for whatever price they receive for biomass from an authorized biomass-using facility. The practical effect of this would be to cut in half the price that biomass facilities must pay for delivered biomass, except that the matching payments are limited to two years. Ethanol plants would not be able to invest the capital for retrofitting to biomass based on lower prices for biomass that are limited to only two years, so BCAP will have little impact on CHP feasibility. It is possible that CHP-based ethanol could have a higher market value because of a lower carbon footprint, in California or states that adopt similar policies. We have not made an estimate of this value, because current California regulations do not include soil carbon losses within the boundary of the LCA (life cycle analysis) for the carbon content of biofuels. Our estimates are that conversion to stover-fired CHP would reduce the GHG intensity of the ethanol by 13.3 gCO2e MJ-1. However, the reduction of Midwest corn ethanol\u27s footprint by that amount would provide a fuel with a GHG reduction of only 11% relative to gasoline, which would result in a minimal carbon premium in California even if their regulations were changed to recognize it. An important contribution of this project has been the estimation of supply curves for various amounts of corn stover or switchgrass to be delivered at one of the three delivery points in the study. Biomass in large quantities may be used for other purposes, such as for co-firing with coal in electrical generating plants, or as a feedstock for cellulosic ethanol. The relationship between delivered price and quantity is important information in the evaluation of any such project. One significant finding of the study is that corn stover price would need to be at least $50 per ton of dry matter to have small amounts of less than 100,000 tons per year delivered, or$55-$62 per ton to have a million tons per year delivered, depending on the location in Nebraska. A second significant finding is the lack of competitiveness of switchgrass as a source of biomass in the area of the study. Given current switchgrass technology, prices would have to be$70-$75 per ton of dry matter for delivery of 100,000 to one million tons per year. The project conducted several background studies to be able to address the above issues, results of which are summarized in the report. We reviewed the history and status of climate change initiatives in the U.S. and internationally, from which we were able to identify carbon credits as possible benefits in the future, and renewable energy credits and BCAP benefits available currently and the near future. We also reviewed and summarized the literature on ethanol\u27s carbon footprint attributable to Indirect Land Use Change (ILUC), and though we did not attempt any original research on this issue, a thesis study was in progress at the close of the project examining the potential effects of corn stover revenues on the expansion of cropland into pasture and hay lands in Nebraska. Finally, we examined the relationships between prices of energy sources in Nebraska (natural gas, electricity, and diesel) to aid in understanding how changing energy prices would affect financial feasibility of retrofitting to CHP

CELL-CENTERED LAGRANGIAN LAX-WENDROFF HLL HYBRID SCHEME ON UNSTRUCTURED MESHES

We have recently introduced a new cell-centered Lax-Wendroff HLL hybrid scheme for Lagrangian hydrodynamics [Fridrich et al. J. Comp. Phys. 326 (2016) 878-892] with results presented only on logical rectangular quadrilateral meshes. In this study we present an improved version on unstructured meshes, including uniform triangular and hexagonal meshes and non-uniform triangular and polygonal meshes. The performance of the scheme is verified on Noh and Sedov problems and its second-order convergence is verified on a smooth expansion test.Finally the choice of the scalar parameter controlling the amount of added artificial dissipation is studied

Potential Vorticity Evolution of a Protoplanetary Disk with An Embedded Protoplanet

We present two-dimensional inviscid hydrodynamic simulations of a protoplanetary disk with an embedded planet, emphasizing the evolution of potential vorticity (the ratio of vorticity to density) and its dependence on numerical resolutions. By analyzing the structure of spiral shocks made by the planet, we show that progressive changes of the potential vorticity caused by spiral shocks ultimately lead to the excitation of a secondary instability. We also demonstrate that very high numerical resolution is required to both follow the potential vorticity changes and identify the location where the secondary instability is first excited. Low-resolution results are shown to give the wrong location. We establish the robustness of a secondary instability and its impact on the torque onto the planet. After the saturation of the instability, the disk shows large-scale non-axisymmetry, causing the torque on the planet to oscillate with large amplitude. The impact of the oscillating torque on the protoplanet's migration remains to be investigated.Comment: 17 pages total with 9 figures (Fig.4,5,9 are in .jpg), accepted to Ap

Distillers Grains and Livestock are Important to Ethanol Energy and Greenhouse Gas Balance

A life cycle assessment of the impact of distillers grains plus solubles (DGS) on mitigation of energy and greenhouse gas (GHG) emissions comparing corn ethanol to gasoline demonstrates the importanceof feeding wet DGS (WDGS) to feedlot cattle to optimize the environmental benefit of ethanol production relative to gasoline. Ethanol produced in Nebraska has a superior environmentalimpact compared to ethanol produced in Iowa or Texas