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Highlights • Deliver kinetic modeling of producing ethanol using Saccharomyces diastaticus LORRE316 in a two-tank continuous fermentation system. • Model giving information of the interaction of different sugar sources in sugar fermentation by using Saccharomyces diastaticus. • Developed three different models to describe the mechanism of ethanol production process. • Found the best mechanism to descript the ethanol fermentation using yeast Saccharomyces diastaticus LORRE316 in two-tank system. • The model give a good result and prove to be able to predict the conversion of bioethanol from the production process. Abstract Experimental data of ethanol fermentation in a two-tank system with cell recycling using sucrose as a substrate were investigated to establish a kinetic model that described the reaction. Flocculent yeast Saccharomyces diastaticus LORRE-316 was used as the fermenting yeast, and the fermentation medium comprised 80 g/L sucrose, 10 g/L yeast extract, 10 g/L peptone, 2 g/L potassium phosphate monobasic (KH 2 PO 4), and 0.5 g/L magnesium sulfate heptahydrate (MgSO 4 ·7H 2 O). Three models, the Monod model, the modified Monod model, and the extended-modified Monod model, were used to describe fermentation, and the extended-modified Monod model described the reaction more accurately than the other two models. The model took substrate limitations plus substrate and ethanol inhibitive effects into consideration, and was modified to include assumptions that included terms for substrates (sucrose, glucose and fructose) and product (ethanol). In addition, the ethanol concentration had a significant effect on cell growth. The results of Lineweaver–Burk plots showed that the maximum specific growth rate (μ MAX) and the Monod constant (K S) were 0.72/h and 26.77 g/L, respectively. The models were suitable for describing the experimental data. Graphical abstracts There were limited numbers of mathematical models for fermentation of sugar to ethanol by using Saccharomyces diastaticus LORRE-316 in previous works. Also, there were still significant discrepancy between the experimental results and their mathematic modeling. There is also no mathematical model express the fermentation reaction of sugar to ethanol by using Saccharomyces diastaticus LORRE-316 in continuous reactor. Therefore, the mathematical for continuous reactor is firstly derived here. Also, in this work, with mechanism derived, the gaps between the experimental data and model are closed. Therefore, the mechanism derived in this work is more rectified. The kinetic parameters also derived in this work. In this model, the priority of sugar utilization was considered. We found that glucose is more prioritize than fructose and sucrose. The inhibition factor of fructose utilization by glucose was represented as the concentration of glucose (1–G/G 0). Experimental data and results of the modified model of ethanol production (Solid line: Model) Figure shows the concentration profiles of the substrates and product in ethanol fermentation generated. At the initial stage, the concentration of glucose and fructose continuously decreased with time. No evident decrease in the concentration of sucrose was reported during this time, indicating that the utilization of glucose and fructose was competitive for sucrose utilization. Hence, the cells used glucose and fructose before sucrose. As the concentration of glucose and fructose reached almost zero, the concentration of sucrose decreased rapidly with time, which confirmed the effect of glucose and fructose concentration on sucrose utilization. With time, the concentration of ethanol increased with the increase in the utilization of the substrates (sucrose, glucose, and fructose) by cells. The concentration of ethanol increased with time following complete consumption of glucose and continued to increase with a rapid decrease in sucrose concentration. Image, graphical abstract [ABSTRACT FROM AUTHOR]

About 85% of petroleum oil need of India is being met through imports. Indian economy is growing steadily resulting in rapid increase of vehicular population and demand for transportation fuels. Indian Government has already mandated blending of ethanol in gasoline by 10% to reduce the oil import. Bureau of Indian Standards is finalizing the specification of 20% ethanol blended gasoline for use as vehicular fuel. In this context, this review presents the current and future scenario of Indian transportation, petroleum oil and bio-fuel sectors including global progress on utilization of ethanol as an alternative transportation fuel in spark ignition vehicles. The data from various standard reference sources were compiled, analyzed and is presented. The review indicates that the gasoline demand would be around 44 billion liters by the year 2020 and India has a potential to produce ethanol to the tune of 30 billion liters per annum in addition to existing capacity. Apart from augmenting production of first generation ethanol, the second generation ligno-cellulosic ethanol and thermo-chemical conversion of carbon-rich agricultural/petroleum residues are seen as alternative options. The potential of such alternative feed stocks and ethanol conversion technologies need to be exploited to increase ethanol availability for blending. The review indicates that ethanol is most suitable fuel for spark ignition engines due to its higher octane number. Ethanol blending reduces sulphur, aromatics, olefin and benzene content in gasoline and can reduce vehicular emissions such as hydrocarbon, carbon monoxide and particulate matter. [ABSTRACT FROM AUTHOR]

Different long-term mitigation scenarios indicate carbon capture and storage associated with biomass (BECCS) might play a significant role in climate-change mitigation efforts, especially when it comes to long-term temperature stabilization. The ethanol fermentation process is considered as an early opportunity for BECCS deployment due to its low capture costs. Being a major ethanol producer, Brazil stands in a privileged position for the development of this technological option. However, previous scientific studies indicate several challenges for the deployment of a CO 2 transportation network in the country, mostly as a result of the associated seasonality of the sugarcane industry and consequent idleness observed in the carbon transportation infrastructure. To address those issues, this study developed and applied a methodology to design an optimum carbon network considering an alternative concept: the incorporation of new CO 2 emission sources aiming at guaranteeing adequate operational flows throughout the year, minimizing idleness and reducing transportation costs. Findings indicate that the incorporation of new CO 2 emission sources reduces transportation costs. The inclusion of CO 2 from both the cogeneration process and fossil sources results in an average levelized cost of transportation of 26 US$/tCO 2 (54% lower than transportation costs in the baseline case). However, this reduction in transportation costs does not compensate for the increase in capture costs, resulting in higher levelized abatement costs for the whole system. Indeed, cases including cogeneration have reached a levelized abatement cost of approximately 125 US$/tCO 2 (84% higher than in the baseline case). Nevertheless, by reducing transportation costs the strategy adopted in this study could facilitate the development of a carbon transportation network. Additionally, the integration of fossil-derived CO 2 has proved beneficial to the system, allowing improvements in flow regularity and reducing idleness problems related to the seasonality of biogenic sources. [ABSTRACT FROM AUTHOR]

Abundant, low prices and a highly reduced nature make glycerol to be an ideal feedstock for the production of reduced biochemicals and biofuels. Escherichia coli has been paid much attention as the platform of microbial cell factories due to its high growth rate (giving higher metabolite production rate) and the capability of utilizing a wide range of carbon sources. However, one of the drawbacks of using E. coli as a platform is its mixed metabolite formation under anaerobic conditions. In the present study, it was shown that ethanol could be exclusively produced from glycerol by the wild type E. coli , while d -lactic acid could be exclusively produced from glucose by pflA.cra mutant, where the glucose uptake rate could be increased by this mutant as compared to the wild type strain. It was also shown that the growth rate is significantly reduced in pflA.cra mutant for the case of using glycerol as a carbon source due to redox imbalance. The metabolic regulation mechanisms behind the fermentation characteristic were clarified to some extent. [ABSTRACT FROM AUTHOR]

Industrial ethanol production usually requires the costly use of commercial cellulase. Herein, we describe the direct use of cellulase produced by Trichoderma reesei RUT-C30 with sugarcane bagasse (SCB) as a substrate for the production of ethanol. The pretreated SCB supplemented with wheat bran (weight ratio of 4:1) was used for T. reesei cellulase production by solid-state fermentation. The cellulase activity titers of 5.5 ± 0.7 FPU/gdm was achieved. The activity increased to 15.0 ± 0.9 FPU/gdm when lactose was used as an inducer. The cellulase contained SCB (CSCB) was used directly as the raw material for ethanol production by Kluyveromyces marxianus at 40 °C, yielding 14.1 ± 1.8% (w/w) of ethanol. Supplementing 5 FPU/gdm of commercial cellulase (Cellic® CTec 2) to CSCB improved the ethanol yield to 30.3 ± 0.4% (w/w). Supplementing Cellic® CTec 2 provided large amount of β-glucosidase activity to CSCB, which hydrolyzes cellobiose to glucose, thereby preventing the inhibition of cellobiose to exoglucanase and endoglucanase. This study demonstrate the feasibility of integrating direct utilization of CSCB without further processing, conversion of CSCB to fermentable sugars, and fermentation of yeast to ethanol in a single reactor. This may be the most efficient way to convert biomass to valuable ethanol. • Production of cellulase by solid-state fermentation of Trichoderma reesei RUT-C30 using bagasse as the main substrate. • Addition of lactose to bagasse can increase the activity of cellulase by 1.7 times. • The fermented bagasse containing cellulase is used directly for ethanol production. • Addition of commercial cellulase (Cellic® CTec2) increases alcohol yield in fermented bagasse. [ABSTRACT FROM AUTHOR]

Sustainable development requires energy source stability and environmental maintenance. Over-exploitation and the intensive use of nonrenewable fossil fuels thus eventually hamper the development of human society. Bioenergy is one solution to this problem. This study formulates a price endogenous, partial equilibrium mathematical model to simulate the economic and environmental effects of bioenergy development in Jiangxi province, China. The result indicates that the farmers' revenue primarily originates from energy sales, government subsidies and emission reduction. An inappropriate subsidy amount will result in inefficient resource allocation; in addition, the marginal benefit from bioenergy production is fairly small. The result also shows that the joint production of bio-electricity and ethanol could be a better choice if climate change mitigation is considered. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bioprocesses are often highly nonlinear due to process variability and complexity of biological systems. In this study, a series of batch experimental study was conducted on ethanol production using combined cassava and rejected mango fruits as a fermentation feedstock. The effects of pH and aeration rate were studied in the experiments. An advanced EMK model was developed to mathematically represent the simultaneous effects of pH and aeration rate on microbial kinetics for a highly nonlinear fermentation. The advantage of this proposed model is that it requires only small number of experimental runs to obtain a high-order order prediction response with an improved accuracy. The results showed that the model can fit the experimental data well within the given ranges of pH and aeration rate used in the study. [ABSTRACT FROM AUTHOR]

Ethanol was produced from oil palm frond juice (OPFJ) by using Saccharomyces cerevisiae yeast cells. Experiments were operated in a batch mode by varying the oil palm age between 3-4, 4-7, 7-10, 10-20 and 20-25 years. Experimental results showed that OPFJ at 3-4 years gave the highest concentrations of glucose and ethanol as 31.26 and 11.50 g/l. Ethanol yield was 0.39 g-ethanol/g-glucose, which estimated as 76.47% of the theoretical yield (0.51 g-ethanol/g-glucose). Additionally, the Monod and modified Gompertz equations were used to describe the kinetics of substrate utilizationand product formation. The values of the kinetic parameters in Monod and modified Gompertz equations of OPFJ extracted from oil palm aged 3-4 years were evaluated: maximum specific growth rate ( μ max ) was 0.29 g/g-VSS.hr, saturation concentration ( K s ) 47.05 g/l, maximum ethanol concentration ( P m ) 11.50 g/l, maximum ethanol production rate ( r p,m ) 0.24 g./l.hr and lag phase 0.12 hr. Both models fitted well to the experimental data, which had the high regression coefficient values (R 2 >0.95). [ABSTRACT FROM AUTHOR]

Ethanol production from oil palm frond (OPF) by simultaneous saccharification and Saccharomyces cerevisiae TISTR5048 fermentation was investigated. Solid fraction of OPF (20% TS) was pretreated by 2% H 2 SO 4 , 2% NaOH and 2% NaOH in H 2 O 2 presoaking at room temperature for 24 hours. Pretreated OPF by presoaking in 2% H 2 SO 4 , 2% NaOH and 2% NaOH in H 2 O 2 contained 37%, 42% and 49% of cellulose, respectively. Pretreated OPF was simultaneous saccharification by cellulase enzyme (Cellic CTec2, Novozymes) and sequentially fermentation. Sugar concentration in OPF cellulose hydrolysis of 2% H 2 SO 4 , 2% NaOH and 2% NaOH in H 2 O 2 presoaking was 45.72, 55.73 and 56.94 g/l, respectively. Ethanol concentration of 2% H 2 SO 4 , 2% NaOH and 2% NaOH in H 2 O 2 presoaking was 14.5, 15.0 and 17.2 g/L, respectively. 2% NaOH in H 2 O 2 presoaking was the best pretreatment with 82.11% of total solids recovery and containing 49.9% of cellulose with enzyme digestion ability of 37.6%. [ABSTRACT FROM AUTHOR]

There is a carbon sequestration benefit to the ethanol manufacturing process if the CO 2 that is created in the fermentation process in an ethanol plant is geologically stored by an enhanced oil recovery (EOR) project. In order to recover one barrel of oil using CO 2 -EOR, an equal or greater amount of CO 2 must be sequestered in order to recover the oil (∼1.0–2.5 tonnes of CO 2 are stored for each tonne of CO 2 emissions resulting from combustion of the recovered oil). The oil produced from a CO 2 -EOR sequestration project is therefore either carbon neutral or carbon negative if the CO 2 is sourced from the fermentation emissions from an ethanol plant. The 40.3 million metric tonnes of CO 2 fermentation emissions vented during the production of 53.4 million liters of ethanol per year in the U.S. could result in production of 40–100 million barrels of carbon negative oil annually. A carbon value chain (CVC) based on carbon credits could incentivize the construction of a CCS infrastructure in the United States that begins with the capture of corn ethanol CO 2 fermentation emissions. Utilization of biofuel fermentation emissions worldwide in bio-CO 2 -EOR sequestration projects would help achieve global CO 2 emission reduction goals. [ABSTRACT FROM AUTHOR]

The ethanol production by recombinant Escherichia coli introducing of pyruvate decarboxylase (pdc) and alcohol dehydrogenase (adhB) from Zymomonas mobilis was investigated under aerobic conditions. In aerobic culture ( K L a = 1.5 min -1 ), the cells expressing pdc and adhB produced 0.4 g l -1 ethanol when cultured for 18 h. This value was improved in BW25113 Δpta /pHfdh/pTadhB-pdc following 4 g l -1 formate feeding at 0.8 g l -1 ethanol. In higher oxygenation level ( K L a = 6.1 min -1 ), the production of ethanol was further enhanced at 1.79 g l -1 ± 0.37 g l -1 after 24 h cultivation. Formate was found not detectable at the end of culture, indicating complete degradation this organic acid to regenerate NADH from NAD + . The culture strategy was effective to inactivate lactate dehydrogenase, which is major competitor for ethanol production in utilizing NADH. [ABSTRACT FROM AUTHOR]

A two step, included process producing ethanol from oil palm fronts (OPF) by two-stage simultaneous saccharification and Saccharomyces cerevisiae fermentation followed by anaerobic digestion of its effluent to produce methane was investigated. OPF was soaked in dilute sulfuric acid, hydrogen peroxide and water consequently pretreated by microwave for preparing of cellulose and followed by simultaneous saccharification and fermentation. The result indicated OPF soaking in water gave a maximal ethanol yield was 0.32 g-ethanol/g-glucose which was 62.75% of the ethanol theoretical yield (0.51g-ethanol/g-glucose). The effluent from the ethanol production process was used to produce methane with the yield of 514 ml CH4/g VS added. Therefore, soaking in water and microwave co-pretreatment could helpful due to its low toxicity and low corrosion compare to sulfuric acid and hydrogen peroxide which improves the efficiency of enzymatic hydrolysis. The maximum energy output of the process (745 kWh/ ton of OPF) was about 72% of the energy contributed by cellulose fraction, contained in the oil palm frond. [ABSTRACT FROM AUTHOR]

The article focuses on the investigation of steam explosion pretreatment of the pruned branches of pear trees for production of bioethanol through saccharification and fermentation of cellulase. Topics discussed include analysis of sugars derivative of cellulase by high performance liquid chromatography, chemical composition of pruned pear branches and production of ethanol from hydrolyzate of the pruned branches by the yeast Kluyveromyces marxianus.

Highlights: [•] First combination of FPS1 knockout and overexpression of GPD2 and GLN1 to study their effect on ethanol production from xylose. [•] We found the same genetic modification with different original strains can produce different results. [•] GLN1 overexpression played key function on increasing the xylose metabolism rate. [•] Genetic engineering strain of F106X produce 18.2% more ethanol than control strain. [ABSTRACT FROM AUTHOR]

Abstract: In the coming years, a range of technological solutions aimed at reducing CO2 emissions should be developed. The objective of this paper is to study the technical feasibility of CO2 recycling into ethanol using solid oxide electrolysis cells (SOEC) technology, simulate the whole process using Aspen Plus™ software and make an economic assessment and a carbon footprint. The results of the economic analysis demonstrated that the ethanol production plant can deliver ethanol at a cost of $1.1/kg, assuming an internal rate of return on investment of 8%. Main challenges for this process are improvement of ethanol synthesis reaction catalysts and the SOEC performance. [Copyright &y& Elsevier]

Abstract: This study aims to assess water footprint of ethanol production from molasses in Kanchanaburi and Suphanburi Provinces of Thailand, based on the water footprint concept methodology. The water footprint of ethanol from molasses can be calculated into three parts: sugar cane, molasses, and ethanol production. The green, blue, and grey water footprints of ethanol production from molasses in the Kanchanaburi Province are 849.7, 209.6, and 45.0 (m3/ton), respectively, whereas those of ethanol in the Suphanburi Province are 708.3, 102.9, and 64.8 (m3/ton), respectively. Study results depend on several factors such as climate, soil, and planting date. These are related and effective to the size of water footprint. Especially, if schedule of planting and harvest date are different, which causes the volume of rainfall to be different; these affect the size of water footprints. A limitation of calculation of grey water footprint from crop process has been based on a consideration rate of nitrogen only. Both provinces in the study area have their respective amount of the grey water footprint of molasses, and ethanol production is zero. The wastewater in molasses and ethanol production have a very high temperature and BOD, whereas the grey water footprint in this study is zero because the wastewater may be stored in pond, or it may be reused in area of factory and does not have a direct discharge into the water system. However, there is a risk for soil and ground water pollution. [Copyright &y& Elsevier]

Lignocellulosic biomass can be used to produce ethanol. The bioconversion process of waste cellulosic materials to ethanol involves two steps: hydrolysis of cellulose to produce reducing sugars, and the fermentation of sugars to ethanol. The response surface methodology (RSM) based on the 2³ factorial Central Composite Design (CCD) was applied to optimize the biotechnological conditions of the enzymatic saccharification of the substrate and ethanol production from a mixture of three waste cellulosic materials, i.e. office paper, newspaper and cardboard in ration of 1:1:1 (w/w). The control sample yielded 4.3 kg ethanol from 100 kg cellulosic waste materials and subsequent to the statistical optimization, the efficiency of the bioprocess was increased almost 2.65-fold, obtaining 11.04 kg ethanol from 100 kg cellulosic waste materials. [ABSTRACT FROM AUTHOR]

Abstract: Biomass energy and carbon capture and storage (BECCS) can lead to a net removal of atmospheric CO2. This paper investigates environmental and economic performances of CCS retrofit applied to two mid-sized refineries producing ethanol from sugar beets. Located in the Region Centre France, each refinery has two major CO2 sources: fermentation and cogeneration units. “carbon and energy footprint” (CEF) and “discounted cash flow” (DCF) analyses show that such a project could be a good opportunity for CCS early deployment. CCS retrofit on fermentation only with natural gas fired cogeneration improves CEF of ethanol production and consumption by 60% without increasing much the non renewable energy consumption. CCS retrofit on fermentation and natural gas fired cogeneration is even more appealing by decreasing of 115% CO2 emissions, while increasing non renewable energy consumption by 40%. DCF shows that significant project rates of return can be achieved for such small sources if both a stringent carbon policy and direct subsidies corresponding to 25% of necessary investment are assumed. We also underlined that transport and storage cost dilution can be realistically achieved by clustering emissions from various plants located in the same area. On a single plant basis, increasing ethanol production can also produce strong economies of scale. [Copyright &y& Elsevier]

The article presents a study on the production of fuel ethanol from xylo-oligosaccharides in xylose-fermenting Saccharomyces cerevisiae. It mentions that Saccharomyces cerevisiae strains are important in ethanol production, as it contain significant amounts of sugar. It notes that bioethanol production from xylo-oligosaccharides holds the possibility for the production of such fuel from lignocellulosic hydrolysate.

Abstract: Yeasts have a long tradition of application in biotechnology and a more recent history of use as research models for biochemistry, metabolism, genetics and cell biology. Without doubt, Saccharomyces cerevisiae has been the dominant representative in all these aspects. There is tremendous diversity among yeasts, however, and the application of modern microbiological and molecular approaches has resulted in renewed focus on the biology and industrial potential of other yeasts. The dairy yeast Kluyveromyces marxianus is of particular interest in this regard because of traits that render it especially suitable for industrial application. These include the fastest growth rate of any eukaryotic microbe, thermotolerance, the capacity to assimilate a wide range of sugars, secretion of lytic enzymes, and the production of ethanol by fermentation. Despite the importance of these traits, and significant exploitation by the biotechnology sector, fundamental research with K. marxianus is just emerging from the shadow of its sister species, Kluyveromyces lactis. The availability of new molecular tools and resources for K. marxianus, its interesting metabolic and cellular traits, and the potential to become the leading yeast for many biotechnological processes, argue strongly for increased research into this particular species. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Thermodynamics is the property of International Centre for Applied Thermodynamics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents a study on the development of a conversion after reduction of viscosity (CARV) process in the production of bioethanol. The study developed the CARV process using simultaneous saccharification and fermentation (SSF). It notes that a mixture of sugar beet and potato mash is a good source for ethanol using the CARV process.

Bacteria and wild yeasts contamination is usually observed during fuel ethanol fermentation. Moreover, it is known that sucrose (the main carbohydrate in sugarcane juice) is breakdown into glucose and fructose by the yeast enzyme invertase, but hydrolysis is much faster than hexoses metabolism, resulting in monosaccharides accumulation which exerts osmotic stress on yeast and growth of Lactobacillus contaminants. Nonetheless, the knowledge about the effect of invertase enzyme on these contaminants is still scarce, especially because the wort composition can differ from exclusive sugarcane juice to a mixture of juice and molasses. Invertase activity and viability of five strains of Saccharomyces cerevisiae (PE-2, BG-1, CAT-1, FLE and IZ-1904) were quantified and correlated with bacterial contamination in fermentations with biomass recycling. Invertase activity was verified to be, in ascending order: CAT-1

• Sequential pretreatments allowed the generation of value-added products from GCF. • Bioactive compounds recovered from adsorption showed high antioxidant activities. • Lignin and arabinoxylan were recovered from alkaline black liquor. • The ethanol production increased by 79.6% using detoxified hydrothermal liquor. • Delignified GCF showed high adsorption capacity of MB dye (≈200 mg/g). The fractionation of agroindustrial and forest residues is a premise of the biorefinery concept. Thus, the present study focuses on pretreatments (hydrothermal and alkaline) and detoxification processes in order to transform green coconut fiber (GCF) into cellulose-rich material, dye biosorbent, bioactive phenolic compounds, lignin and arabinoxylan. The adsorption onto Amberlite XAD-7HP resin allowed the best recovery of phenolic compounds from hydrothermal pretreatment liquor, which presented potent antioxidant activities such as inhibition of hydroxyl and superoxide radicals of 77.05% and 76.88%, respectively. Acid precipitation was effective to recover 41.23% of the initial lignin content from alkaline pretreatment liquor. The detoxified hydrothermal pretreatment liquor was used as an additional source of glucose, increasing the final concentration of ethanol by 79.6% in simultaneous saccharification and fermentation of delignified GCF. Using delignified GCF as biosorbent, made it possible to obtain a static adsorption capacity of 200 mg of methylene blue dye per gram of biosorbent and good recyclability in dynamic experiments. Therefore, the proposed methodology guarantees a practical way of manufacturing value-added products from lignocellulosic materials. [ABSTRACT FROM AUTHOR]

Considering the production goals for cellulosic and advanced biofuels in the Energy Independence and Security Act of 2007 (EISA), this study compares production costs and returns on invested capital for two current and three proposed ethanol technologies. Two methods use corn grain as the feedstock, and three use cellulosic feedstocks of corn stover, switchgrass and wood chips. Baseline levels are established so sensitivity analyses of rates of return on invested capital can be performed as market and performance variables vary. Monte Carlo techniques are used to determine distributions of rates of return for each technology capable of producing ethanol. [ABSTRACT FROM AUTHOR]

US ethanol production should exceed 12 billion gallons by 2010, and EISA 2007 mandates 36 billion gallons by 2022, diverting one-third of corn to ethanol and 13% of soybean production to biodiesel. Increased demand will ricochet through other agricultural sectors and alter production patterns and land use in the Corn Belt. This paper discusses effects of biofuel expansion on land and water resources. While US ethanol production will have large effects on international land use, there will likely be conversion of grassland to row crops, increased use of nitrogen fertiliser and pesticides, and increases in soil erosion in the Midwest. [ABSTRACT FROM AUTHOR]