Abstract  This study conducted the updated simulations to depict a life cycle analysis (LCA) of the biodiesel production from soybeans and other feedstocks in the U.S. It addressed in details the interaction between LCA and induced land use change (ILUC) for biodiesel. Relative to the conventional petroleum diesel, soy biodiesel could achieve 76% reduction in GHG emissions without considering ILUC, or 66-72% reduction in overall GHG emissions when various ILUC cases were considered. Soy biodiesel's fossil fuel consumption rate was also 80% lower than its petroleum counterpart. Furthermore, this study examined the cause and the implication of each key parameter affecting biodiesel LCA results using a sensitivity analysis, which identified the hot spots for fossil fuel consumption and GHG emissions of biodiesel so that future efforts can be made accordingly. Finally, biodiesel produced from other feedstocks (canola oil and tallow) were also investigated to contrast with soy biodiesel and petroleum diesel.

Abstract  Seeds for the historic drought of 2012 were sown during the back-to-back La Niña episodes of 2010–11 and 2011–12. La Niña, a name given to anomalous cooling of the equatorial waters of the central and eastern Pacific Ocean, often correlates with drought development and expansion across the southern United States. Indeed, drought began to develop across the southern tier of the U.S. during the winter of 2010–11, and quickly intensified during the 2011 growing season. Effects of the 2011 drought were particularly severe in the south-central U.S.

Abstract  Fuel ethanol consumption has grown significantly in the past several years, and it will continue to grow with the establishment of a renewable fuel standard (RFS) in the Energy Policy Act of 2005 (P.L. 109-58) and the expansion of that RFS in the Energy Independence and Security Act of 2007 (P.L. 110-140). This standard requires U.S. transportation fuels to contain a minimum amount of renewable fuel, including ethanol. Most of the U.S. market is supplied by domestic refiners producing ethanol from American corn. However, imports play a small but growing role in the U.S. market. One reason for the relatively small role is a 2.5% ad valorem tariff and (more significantly) a 54-cent-per-gallon added duty on imported ethanol. These duties offset an economic incentive of 51 cents per gallon for the use of ethanol in gasoline. However, to promote development and stability in the Caribbean region and Central America, the Caribbean Basin Initiative (CBI) allows the imports of most products, including ethanol, duty-free. While many of these products are produced in CBI countries, ethanol entering the United States under the CBI is generally produced elsewhere and reprocessed in CBI countries for export to the United States. The U.S.- Central America Free Trade Agreement (CAFTA) would maintain this duty-free treatment and set specific allocations for imports from Costa Rica and El Salvador. Duty-free treatment of CBI ethanol has raised concerns, especially as the market for ethanol has the potential for dramatic expansion under P.L. 109-58 and P.L. 110-140.

Abstract  Ethanol production from cellulosic material is considered one of the most promising options for future biofuel production contributing to both the energy diversification and decarbonization of the transport sector, especially where electricity is not a viable option (e.g., aviation). Compared to conventional (or first generation) ethanol production from food and feed crops (mainly sugar and starch based crops), cellulosic (or second generation) ethanol provides better performance in terms of greenhouse gas (GHG) emissions savings and low risk of direct and indirect land-use change. However, despite the policy support (in terms of targets) and significant R&D funding in the last decade (both in EU and outside the EU), cellulosic ethanol production appears to be still limited. The paper provides a comprehensive overview of the status of cellulosic ethanol production in EU and outside EU, reviewing available literature and highlighting technical and non-technical barriers that still limit its production at commercial scale. The review shows that the cellulosic ethanol sector appears to be still stagnating, characterized by technical difficulties as well as high production costs. Competitiveness issues, against standard starch based ethanol, are evident considering many commercial scale cellulosic ethanol plants appear to be currently in idle or on-hold states.

Abstract  Transportation is the largest source of greenhouse gas emissions in the United States, with petroleum accounting for 90 percent of transportation fuels. Policymakers encounter a range of questions as they consider low-carbon fuel standards to reduce emissions, including total emissions released from production to use of a fuel or the potential consequences of a policy. Life-cycle assessment is an essential tool for addressing these questions. This report provides researchers and practitioners with a toolkit for applying life-cycle assessment to estimate greenhouse gas emissions, including identification of the best approach to use for a stated policy goal, how to reduce uncertainty and variability through verification and certification, and the core assumptions that can be applied to various fuel types. Policymakers should still use a tailored approach for each fuel type, given that petroleum-based ground, air, and marine transportation fuels necessitate different considerations than alternative fuels including biofuels, hydrogen, and electricity. Ultimately, life-cycle assessments should clearly document what assumptions and methods are used to ensure transparency.

Abstract  This report provides projections for the agricultural sector to 2029. Projections cover agricultural commodities, agricultural trade, and aggregate indicators of the sector, such as farm income. The projections are based on specific assumptions about macroeconomic conditions, policy, weather, and international developments, with no domestic or external shocks to global agricultural markets. The Agriculture Improvement Act of 2018 is assumed to remain in effect through the projection period. The projections are one representative scenario for the agricultural sector for the next decade and reflect a composite of model results and judgment-based analyses. The projections in this report were prepared during July 2019 through January 2020, with the commodity projections based off the conditions as of the October 2019 WASDE. While agricultural crop prices are tending to trend upwards only slowly in nominal terms, U.S. trade disputes with China that existed at the time of these projections were formulated have dampened expectations, particularly for soybeans. These projections assume the trade disputes to continue the duration of the projection period. Planted acreage drops slightly overall compared to recent years, primarily due to expected lower soybean plantings, while corn and wheat plantings are expected to remain mostly unmoved. Acreage enrolled in the Conservation Reserve Program (CRP) is also expected to rise, lowering total acres to the eight main crops. Energy costs are expected to increase, with crude oil import prices reaching $91 per barrel at the end of the projection. Low feed costs and continued strong global demand provide economic incentives for expansion in the livestock sector. Long-run developments for global agriculture reflect steady world economic growth and continued global demand for biofuel feedstocks, factors which combine to support longer run increases in disappearance, trade, and, to a lesser extent, prices of agricultural products. Although a relatively strong but slowly weakening U.S. dollar is expected to dampen growth in U.S. agricultural exports, the United States remains competitive in global agricultural markets, in part due to efficiency gains. Net farm income is expected to increase $1.4 billion in 2020 to $93.9 billion and remaining between $88.8 and $98.6 billion for the remainder of the decade, trending upward during the latter half

Abstract  Expanding the domestic bioeconomy can help diversify the use of national resources and reduce emissions. Evaluating the sustainability of a growing bioeconomy, however, is inherently complex since it spans several sectors and supply chains. It requires a comprehensive, integrated analysis framework to assess the developments across the traditional sustainability dimensions. Further, the assessment of bioeconomy developments requires a robust baseline of historic data and trends. In this paper, we analyze the evolution of the biofuel portion of the US bioeconomy, focusing on two fuels that had an exponential growth in the last two decades: corn ethanol and soybean biodiesel. For this purpose, we created a novel time series of harmonized environmentally-extended input-output (EEIO) tables based on a publicly available model from the US Environmental Protection Agency and expanded its disaggregation to reflect the main supply chains of the biofuels sectors. The EEIO time series provides the historical evolution of these biofuels relative to the rest of the economy as well as on an energy-unit basis. We find that, except for energy use, the broader US economy declined in both resource intensity and most environmental impacts when normalized per one million dollars of gross domestic product. Deviating from this trend are freshwater ecotoxicity and human toxicity, mainly attributable to the expansion of commodity crops and the increase of domestic oil and gas extraction respectively. We also find that the biofuel industry's total socioeconomic, resource use and environmental impacts grew with their production increases over time. However, the industry's maturation and scale-up, combined with higher feedstock yields, contributed to a reduction of most impacts on an energy-unit basis over time.

Abstract  Carbon intensities are calculated under the LCFS on a full life cycle basis. This means that the carbon intensity value assigned to each fuel reflects the GHG emissions associated with that fuel’s production, transport, storage, and use. Traditionally, only these steps, termed direct effects, have been included in the life cycle assessment of transportation fuels. In addition to these direct effects, some fuel production processes generate GHGs indirectly, via intermediate market mechanisms. Stakeholders participating in the LCFS process have suggested that most or all transportation fuels generate varying levels of indirect GHG emissions. To date, however, ARB staff has only identified one indirect effect that has a measurable impact on GHG emissions: land use change effects. A land use change effect is initially triggered when an increase in the demand for a crop-based biofuel begins to drive up prices for the necessary feedstock crop. This price increase causes farmers to devote a larger proportion of their cultivated acreage to that feedstock crop. Supplies of the displaced food and feed commodities subsequently decline, leading to higher prices for those commodities. Some of the options for many farmers to take advantage of these higher commodity prices are to take measures to increase yields, switch to growing crops with higher returns, and to bring non-agricultural lands into production. When new land is converted, such conversions release the carbon sequestered in soils and vegetation. The resulting carbon emissions constitute the “indirect” land use change (iLUC) impact of increased biofuel production. Based on research and published work, most of the land use change impacts result from the diversion of food crops to producing biofuels. During the regulatory process (i.e., workshops and meetings with stakeholders) leading up to the 2009 LCFS Board Hearing, the magnitude of this impact was discussed and also questioned by renewable fuel advocates. Land use change is driven by multiple factors, some of them not related to the production of biofuels. Because the tools for estimating land use change were few and relatively new when the regulation was originally adopted in 2009, biofuel producers argued that land use change impacts should be excluded from carbon intensity values, pending the development of better estimation techniques. Based on its work with land use change academics and researchers, however, ARB staff concluded that the land use impacts of crop-based biofuels were significant, and must be included in LCFS fuel carbon intensities. To exclude them would assume that there is zero impact resulting from the production of biofuels and would allow fuels with carbon intensities that are similar to gasoline and diesel fuel to function as low-carbon fuels under the LCFS. This would delay the development of truly low-carbon fuels, and by not accounting for the GHG emissions from land use change, would jeopardize the achievement of a ten percent reduction in fuel carbon intensity by 2020. Details of ARB’s estimated land use change impacts of biofuel crop production for the 2009 regulation is provided in the ISOR from 20091. Since 2009, there have been numerous peer-reviewed publications, dissertations, and other scientific literature, that have focused on various aspects of indirect land use changes related to biofuels. Staff has reviewed published articles, contracted with academics, and consulted with experts, all of which have led to significant improvements to the GHG modeling methodologies and analysis completed in 2009. Complete details of the updates and results from the current analysis are presented in this section.

Abstract  The National Energy Technology Laboratory produced a well-to-wheels (WTW) life cycle greenhouse gas analysis of petroleum-based fuels consumed in the U.S. in 2005, known as the NETL 2005 Petroleum Baseline. This study uses a set of engineering-based, open-source models combined with publicly available data to calculate baseline results for 2014. An increase between the 2005 baseline and the 2014 results presented here (e.g., 92.4 vs 96.2 g CO2e/MJ gasoline, + 4.1%) are due to changes both in modeling platform and in the U.S. petroleum sector. An updated result for 2005 was calculated to minimize the effect of the change in modeling platform, and emissions for gasoline in 2014 were about 2% lower than in 2005 (98.1 vs 96.2 g CO2e/MJ gasoline). The same methods were utilized to forecast emissions from fuels out to 2040, indicating maximum changes from the 2014 gasoline result between +2.1% and -1.4%. The changing baseline values lead to potential compliance challenges with frameworks such as the Energy Independence and Security Act (EISA) Section 526, which states that Federal agencies should not purchase alternative fuels unless their life cycle GHG emissions are less than those of conventionally produced, petroleum-derived fuels.

Abstract  BACKGROUND: The GTAP model has been used to estimate biofuel policy induced land use changes and consequent GHG emissions for more than a decade. This paper reviews the history of the model and database modifications and improvements that have occurred over that period. In particular, the paper covers in greater detail the move from the 2004 to the 2011 database, and the inclusion of cropland intensification in the modeling structure.

RESULTS: The results show that all the changes in the global economy and agricultural sectors cause biofuels induced land use changes and associated emissions can be quite different using the 2011 database versus 2004. The results also demonstrate the importance of including land intensification in the analysis. The previous versions of GTAP and other similar models assumed that changes in harvested area equal changes in cropland area. However, FAO data demonstrate that it is not correct for several important world regions. The model now includes land intensification, and the resulting land use changes and emission values are lower as would be expected.

CONCLUSIONS: Dedicated energy crops are not similar to the first generation feedstocks in the sense that they do not generate the level of market-mediated responses which we have seen in the first-generation feedstocks. The major market-mediated responses are reduced consumption, crop switching, changes in trade, changes in intensification, and forest or pasture conversion. These largely do not apply to dedicated energy corps. The land use emissions for cellulosic feedstocks depend on what we assume in the emissions factor model regarding soil carbon gained or lost in converting land to these feedstocks. We examined this important point for producing bio-gasoline from miscanthus. Much of the literature suggests miscanthus actually sequesters carbon, if grown on the existing active cropland or degraded land. We provide some illustrative estimates for possible assumptions. Finally, it is important to note the importance of the new results for the regulatory process. The current California Air Resources Board carbon scores for corn ethanol and soy biodiesel are 19.8 and 29.1, respectively (done with a model version that includes irrigation). The new model and database carbon scores are 12 and 18, respectively, for corn ethanol and soy biodiesel. Thus, the current estimates values are substantially less than the values currently being used for regulatory purposes.

Abstract  Few of the numerous published studies of the emissions from biofuels-induced "indirect" land use change (ILUC) attempt to propagate and quantify uncertainty, and those that have done so have restricted their analysis to a portion of the modeling systems used. In this study, we pair a global, computable general equilibrium model with a model of greenhouse gas emissions from land-use change to quantify the parametric uncertainty in the paired modeling system's estimates of greenhouse gas emissions from ILUC induced by expanded production of three biofuels. We find that for the three fuel systems examined--US corn ethanol, Brazilian sugar cane ethanol, and US soybean biodiesel--95% of the results occurred within ±20 g CO2e MJ(-1) of the mean (coefficient of variation of 20-45%), with economic model parameters related to crop yield and the productivity of newly converted cropland (from forestry and pasture) contributing most of the variance in estimated ILUC emissions intensity. Although the experiments performed here allow us to characterize parametric uncertainty, changes to the model structure have the potential to shift the mean by tens of grams of CO2e per megajoule and further broaden distributions for ILUC emission intensities.

Abstract  We estimate emissions from indirect land-use change associated with U.S. corn ethanol production by using the updated Center for Agricultural and Rural Development/Food and Agricultural Policy Research Institute global agricultural outlook model, which incorporates sub-national land-use modeling in Brazil and endogenous crop yield-price relationships. Emissions estimates range between 9.7-23.9g CO2 per mega Joule (MJ(-)(1)), which is consistent with other estimates. We compare the results of the current model to the 2008 model version. Using the data from the 2016 model in the 2008 model results in emissions that range from 23.2-32.2g CO2 MJ(-)(1). The addition of detailed modelling in Brazil, for example, double-cropping, reduced estimates considerably and highlights the importance of continuous improvements in global agricultural models.

Abstract  Estimates of biofuel carbon intensity are uncertain and depend on modeled land use change (LUC) emissions. While analysts have focused on economic and agronomic assumptions affecting the quantity of land converted, researchers have paid less attention to how models classify land into broad categories and designate some categories as ineligible for LUC. To explore the effect of these land representation attributes, we use three versions of a global human and Earth systems model, GCAM, and compute the "carbon intensity of land-use change" (CI-LUC) from increased U.S. corn ethanol production. We consider uncertainty in model parameters along with the choice of land representation and find the latter is one of the most influential parameters on estimated CI-LUC. A version of the model that protects 90% of non-commercial land reduced estimated CI-LUC by an average of 32% across Monte Carlo trials compared to our baseline model. Another version that mimics the GTAP-BIO-ADV land representation, which protects all non-commercial land, reduced CI-LUC by an average of 19%. The results of this experiment demonstrate that land representation in biofuel LUC models is an important determinant of CI-LUC.