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The food vs. fuel debate has heated up since the 2008 global food crisis when major crop prices dramatically increased. Heavily subsidized biofuel production was blamed for diverting food crops from food production and diverting resources from food and feed production, triggering a food crisis globally and leading to increases in the world food insecure population. Few studies have quantified the effects of biofuel policies on world food prices and world food insecurity. This study added the Brazil and China's biofuel sectors to an existing global trade CGE model, and applies the measurement of food insecurity as developed by FAO. Alternative scenarios were food insecurity. Results are examined with focus on (1) effects on domestic biofuel productions, (2) change in food commodity productions and trade, (3) change in land use and land rents, and (4) change in regional undernourished populations. Results indicated that biofuel expansion is not cost competitive to traditional fossil fuel. Without any policy incentives, huge expansion of biofuel production is not likely under current technology. The conventional biofuel mandates in U.S., Brazil and China lead to increases in world food insecurity, while the advanced biofuel mandate in U.S. has the opposite effect. Subsidies to biofuels production help to lessen the increase in world food insecurity that is caused by increases in conventional biofuel production. Additionally, the effects from U.S. biofuel policies are smaller but more widespread than the effects from Brazil or China's biofuel policies. Overall, the long term effects of biofuel production expansion on world food insecurity are much smaller than expected.

Thermotoga petrophila is a hyperthermophilic anaerobic bacterium that grows optimally at 80?? C. It can utilize plant biomass to produce biofuels, including ethanol and hydrogen, which are alternative and renewable sources of energy. Xylan, microcrystalline avicel PH105, switchgrass, corn husks and wheat straw were used as growth substrates to determine T. petrophila???s capability to use different types of plant biomass for the production of ethanol and hydrogen. The metabolism of cellulosic substrates was analyzed by integrating proteomics analysis, gene identification, cellulase and xylanase activities, growth, metabolic products and cell adhesion. T. petrophila showed best growth on xylan, followed by corn husks, switchgrass, avicel PH105 and wheat straw. The optimal pH for higher biofuel yield was within the range of 8.0 to 8.5. The metabolic end products were H2, CO2, acetate, lactate, formate and succinate when T. petrophila grew on all the tested cellulosic materials. The highest yield of hydrogen (9.6 mM) and the highest yield of ethanol (0.95 mM) were both detected when T. petrophila was grown on xylan. No growth was observed on xylose, which was not expected because T. petrophila grew very well on xylan, a ??-1, 4-xylopryranose polymer from which xylose can be produced upon hydrolysis. The possible reason for this phenomenon may be that T. petrophila has no specific sugar transporters for xylose, although it contains all the genes encoding xylose metabolizing enzymes. The majority of exoglucanases and endoglucanases presented in T. petrophila were extracellular enzymes. The highest specific activities of exoglucanase (1361.3 mU/mg) and endoglucanase (1032.1 mU/mg) in T. petrophila were found in the supernatants of the growth culture with xylan as the sole substrate, indicating that xylan, not cellulose, is the best inducer to increase the expression of extracellular cellulases. Compared to the huge discrepancy of extracellular cellulases activities among different substrates (from 0 to 1361.3 mU/mg), intracellular cellulase (endoglucanase) activity was relatively steady (around 150 mU/mg). Xylanase activity was also detected in both the supernatant and the cell free extract; thus T. petrophila contains both extracellular and intracellular xylanase. The highest xylanase activity was detected in the cell free extract when T. petrophila was grown on cellobiose and xylan (3732.4 mU/mg and 3152.8 mU/mg, respectively), indicating that the majority of xylanase is an intracellular enzyme, and xylan and cellobiose are the best inducers to increase the expression of xylanase. Adhesion of T. petrophila cells to xylan, with many filaments connecting all the cells, was observed using scanning electron microscope and fluorescent staining microscope, whereas there was no attachment between cells and cellulose. This difference may explain why T. petrophila grew much better on xylan than on cellulose because cell adhesion increases enzyme concentration near the substrate to improve the efficiency of cellulosic material utilization. Furthermore, proteomics analysis was used to quantify all the expressed proteins in different growth media with various substrates. The proteomics data revealed that the most important enzymes for cellulose and hemicellulose utilization were ATP binding cassette (ABC) transporters, S-layer proteins and membrane binding proteins, which were up-regulated when T. petrophila was grown on cellulosic materials. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) also indicated the up-regulated proteins from the media with cellulosic substrates were probably ABC transporters and S-layer proteins based on the size of proteins. Based on the gene identification, end product determination and proteomics analysis, the tentative cellulosic material metabolic pathways in T. petrophila were completely profiled. Overall, our results suggest that the ability of T. petrophila to convert cellulosic materials into hydrogen and ethanol exceeds T. maritima, which is a model strain for studying hyperthermophiles. T. petrophila has great potential in applications of producing highly thermostable cellulases and biofuels from cellulosic materials. However, the mechanism of cell adhesion between T. petrophila and xylan and the regulation of the entire cellulosic materials metabolic pathway need further investigation.

This study develops the water requirement factors for different thermo-chemical and biochemical biomass conversion pathways for production of biofuels and biopower. Twelve biomass conversion pathways based on six biomass feedstocks are assessed. For all these pathways integrated water and energy requirement factors are developed. The biomass feedstocks considered for bioethanol production are corn, wheat, corn stover, wheat straw, and switchgrass. The biomass feedstock considered for biodiesel production is canola seed. Three biomass feedstocks are considered for biopower generation using direct combustion of biomass and bio-oil produced from the feedstocks through fast pyrolysis. These three feedstocks are corn stover, wheat straw and switchgrass. The water requirement is also evaluated for biofuels production based on wheat, wheat straw and canola seed in Alberta. Agriculture residues based ethanol production pathways are water and energy efficient, consuming only 0.3 liters of water per MJ of net energy value (NEV), whereas biopower pathways consume about 1.2 1.5 liters of water per MJ of NEV due to their lower energy efficiency. The pathway for producing ethanol from switchgrass is the most energy efficient, but consumes 117 liters of water per MJ of NEV. Producing biopower through the direct combustion of switchgrass and from combustion of switchgrass based bio-oil consumes 278 and 344 liters of water per MJ of NEV, respectively. Wheat and corn based ethanol production pathways consume 653 and 409 liters of water per MJ of NEV, respectively. Canola seed based biodiesel production pathway consumes 176 liters of water per MJ of NEV. Water demand in Alberta due to biofuels production will be 12.7% higher than the projected demand in 2025, but it can be met using existing resources. / Engineering Management

Laminar flame speed of a novel liquid bio-fuel has been determined experimentally using a closed spherical combustion vessel of 29 L equipped with two pairs of fused silica windows for optical access at atmospheric pressure and elevated temperature conditions. Schlieren technique was used to visualize and record the temporal evolution of the outwardly spherical flame front, and an in-house developed Matlab code was employed to process the flame front images and calculate its area by applying several image processing techniques. The test conditions consisted of varying the fuel-air mixture equivalence ratio at atmospheric standard pressure and different initial temperatures. Validation of the present method was achieved by measuring and comparing the flame speed of methane/air and n-heptane/air mixture with their published counterparts. Experimental results revealed comparable laminar flame speed of the novel liquid biofuel (1, 3- dimethoxyoctane) to heavy liquid hydrocarbons such as n-heptane and isooctane, especially at stoichiometric and fuel rich conditions. Additionally, the flammability limits of this novel fuel showed similarities with those of gaseous hydrocarbons fuels (e.g. methane, ethane) but higher than those of liquid hydrocarbons (e.g. diesel, gasoline). / February 2016

Biofuel cells (BFCs) use either enzymes or bacteria to catalyse a fuel to generate power. Their advantages over conventional fuels is that they do not use precious metals and the high selectivity of biocatalysts mean that no separation membranes are required between the electrodes. However, the application of BFCs is limited by their low power output and poor enzyme lifetimes. This thesis addresses these limitations by investigating aligned carbon nanotubes (aCNTs) as potential electrode materials. These aCNT electrodes offer high surface areas to increase enzyme coverage and hence power output and their surface topology can stabilise the enzymes to ensure maximum lifetime and current density.A novel BFC half cell was developed using aCNTs and the fungal enzyme, Trametes versicolor laccase which catalyses the four-electron reduction of oxygen to water. Laccase was shown to communicate directly with the nanotubes enabling the oxidant reduction reaction to be monitored without the need for mediators. Initial investigations compared aCNTs with other commonly reported carbon electrodes and found that the current densities were ~30-fold higher on the aCNTs than at pyrolytic graphite edge electrodes. The high surface area of these electrodes contributed to greater electroactive coverage of enzyme and minimal loss of enzyme upon deposition. Cathodic currents increased linearly with geometric electrode area; however they did not scale with actual electrode surface area and the current density was limited to the order of μA cm-2 due to O2-transport limitations. It was also discovered that the porous contribution of these aCNT electrodes could lead to misleading interpretations on nanotube electrochemistry. This effect was observed when increments in electrode area resulted in apparently significantly faster kinetics. This improvement in catalytic behaviour was proposed to be due to a transition from mass diffusion limited to thin layer cell behaviour exhibited by porous materials. Thermal pretreatment of the aCNT electrodes in oxidative and reductive atmospheres were found to improve their performance. These treatments worked by changing the nanotube surface chemistry and purifying the nanotubes, as evidenced by various physical characterisation methods. Furthermore, laccase activity was enhanced significantly after electrodes had been treated under both atmospheres, where it was believed that the removal of contaminant material and higher defect densities increased electrochemical performance.Finally, mass transport limitations were addressed by developing micro-patterned aCNT electrodes which possessed channels in the arrays, allowing better oxygen diffusion. Fundamental studies showed higher current densities per surface area and thus represent a promising electrode for future BFC research.

Traditional terrestrial crops are currently being utilized as a feedstock for biofuels but resource requirements and low yields limit the sustainability and scalability. Comparatively, next generation feedstocks, such as microalgae, have inherent advantages such as higher solar energy efficiencies, larger lipid fractions, utilization of waste carbon dioxide, and cultivation on poor quality land. The assessment of microalgae-based biofuel production systems through lifecycle, technoeconomic, and scalability assessments has been forced to extrapolate laboratory-scale data due to the immaturity of the technology. This type of scaling leads to large uncertainty in the current near-term productivity potential and ultimately the results from modeling work that rely on this type of modeling. This study integrated a large-scale validated outdoor microalgae growth model that utilizes 21 species and reactor-specific inputs that accurately account for biological effects such as nutrient uptake, respiration, and temperature with hourly historical meteorological data from around the world to determine the current global productivity potential. A global map of the microalgae lipid and biomass productivity has been generated based on the results of annual simulations at 4,388 global locations spread over the seven continents. Maximum annual average yields between 24-27 m3·ha-1·yr-1 are found in Australia, Brazil, Colombia, Egypt, Ethiopia, India, Kenya, and Saudi Arabia with the monthly variability (minimum and maximum) yields of these locations ranging between 14 and 33 m3·ha-1·yr-1. A scalability assessment that leverages geographic information systems data to evaluate geographically realized microalgae productivity, energy consumption, and land availability has been performed highlighting the promising potential of microalgae-based biofuels compared to traditional terrestrial feedstocks. Results show many regions can meet their energy requirements through microalgae production without land resource restriction. Discussion focuses on sensitivity of monthly variability in lipid production compared to annual average yields, biomass productivity potential, effects of temperature on lipid production, and a comparison of results to previous published modeling assumptions.

This study examines the feasibility of producing sweet sorghum as an ethanol feedstock in Mississippi. An enterprise budgeting system is used along with estimates of transportation costs to estimate farmers’ breakeven costs for producing and delivering sweet sorghum biomass. This breakeven cost for the farmer, along with breakeven costs for the producer based on wholesale ethanol price, production costs, and transportation and marketing costs for the refined ethanol, is used to estimate the amounts that farmers and ethanol producers would be willing to accept (WTA) and willing to pay (WTP), respectively, for sweet sorghum biomass. These WTA and WTP estimates are analyzed by varying key factors in the biomass and ethanol production processes. Deterministic and stochastic models are used to estimate profits for sweet sorghum and competing crops in two representative counties in Mississippi, with sweet sorghum consistently yielding negative per-acre profits in both counties.

The act of decision making involves a choice amongst tradeoffs. In agriculture this is no different. This dissertation is composed of four papers that examine the tradeoffs being made across different agricultural decision making processes. The first two papers examine the tradeoffs made at the individual producer level while the last two papers examine tradeoffs made at the national policy level. The first paper investigates farmer attitudes towards how a hypothetical set of production practices referred to as "]conservation agriculture" will affect yield, labor use, erosion, and cost in two communities of Bolivar province, Ecuador. By evaluating the tradeoffs producers are willing to make when choosing to adopt such practices, changes in producer welfare associated with adoption may be identified. These measures can assist in identifying constraints to adoption and aid in extension and policy outreach development. The second paper aims to gain a better understanding of the dynamic relationship between farmers and food buyers. This issue is examined from the perspective of small-scale specialty crop producers who are currently or are considering marketing their products into wholesale food markets. With a focus on farms in Virginia and North Carolina, this study seeks to identify key contract characteristics and buyer attributes which are valued by small-scale specialty crop producers; quantify tradeoffs small-scale specialty crop producers are willing to make between buyer attributes and contract characteristics when establishing a new contractual relationship; and determine the factors influencing these tradeoffs. The third and fourth papers examine the demands that U.S. biofuel production has placed on domestic nutrient fertilizer production. A key argument in favor of domestic biofuel production is that it is a renewable path towards energy independence. However the inputs used in the production of biofuel feedstock, primarily fertilizer nutrients, are anything but renewable. These two papers add to the discussion surrounding biofuel policies by asking an important question that has not received the attention it deserves: "What about the non-renewable inputs (e.g., nutrient fertilizers) that go into producing the inputs (e.g., corn) used for biofuel production?" / Ph. D.

Master of Agribusiness / Department of Agricultural Economics / Jason Bergtold / Markets for alternative fuels are emerging and are of great interest to both public and private companies, as well as government agencies looking to differentiate fuel sources to achieve improved and sustainable operational efficiencies. This creates a growing need for innovation and an increased supply of biofuel feedstocks for bioenergy options such as bio-jet fuel. This thesis aims to assess the logistical feasibility of producing oilseed bio feedstocks and the practicality of building new crush facilities specifically for bio-jet fuel production in Kansas. A logistical optimization model is built by applying data to estimate the potential Kansas supply of rapeseed as a possible feedstock option; transportation and facility costs associated with building; and proposed crushing facility sites, by considering the estimated demand for bio-jet fuel within Kansas. The developed optimization model determined that even average yields per acre and modest adoption rates by farmers willing to incorporate rapeseed into their crop rotations could provide enough feedstock to supply one or two crushing facilities, depending on a variety of additional factors, including bio-jet fuel demand in Kansas. Sensitivity analysis was performed on key model factors and determined that the most influential factor on both size and number of proposed crushing facilities was the market demand for bio-jet fuel. Ultimately, further research is required to better understand the actual market demand for bio-jet fuel within Kansas and how competition or supply supplementation of other bio feedstocks can affect the size or number of proposed crushing facilities. There are currently six oilseed crushing facilities operating in Kansas; although all are dedicated to soybean or sunflower seed. Further studies may find these sites as viable alternative options to building new crushing facilities for a separate type of feedstock.