Science.gov

Sample records for future biofuel production

  1. Future prospects of microalgal biofuel production systems.

    PubMed

    Stephens, Evan; Ross, Ian L; Mussgnug, Jan H; Wagner, Liam D; Borowitzka, Michael A; Posten, Clemens; Kruse, Olaf; Hankamer, Ben

    2010-10-01

    Climate change mitigation, economic growth and stability, and the ongoing depletion of oil reserves are all major drivers for the development of economically rational, renewable energy technology platforms. Microalgae have re-emerged as a popular feedstock for the production of biofuels and other more valuable products. Even though integrated microalgal production systems have some clear advantages and present a promising alternative to highly controversial first generation biofuel systems, the associated hype has often exceeded the boundaries of reality. With a growing number of recent analyses demonstrating that despite the hype, these systems are conceptually sound and potentially sustainable given the available inputs, we review the research areas that are key to attaining economic reality and the future development of the industry. PMID:20655798

  2. Present and potential future oilseed production systems for biofuels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    U.S. agriculture is now depended on to produce renewable energy in addition to food, feed, and fuel, which if not properly managed could threaten long-term sustainability of our agricultural lands. Biofuels produced from oilseed crops, primarily biodiesel, will be an important addition to the renewa...

  3. Projecting future grassland productivity to assess the sustainability of potential biofuel feedstock areas in the Greater Platte River Basin

    USGS Publications Warehouse

    Gu, Yingxin; Wylie, Bruce K.; Boyte, Stephen; Phyual, Khem

    2014-01-01

    This study projects future (e.g., 2050 and 2099) grassland productivities in the Greater Platte River Basin (GPRB) using ecosystem performance (EP, a surrogate for measuring ecosystem productivity) models and future climate projections. The EP models developed from a previous study were based on the satellite vegetation index, site geophysical and biophysical features, and weather and climate drivers. The future climate data used in this study were derived from the National Center for Atmospheric Research Community Climate System Model 3.0 ‘SRES A1B’ (a ‘middle’ emissions path). The main objective of this study is to assess the future sustainability of the potential biofuel feedstock areas identified in a previous study. Results show that the potential biofuel feedstock areas (the more mesic eastern part of the GPRB) will remain productive (i.e., aboveground grassland biomass productivity >2750 kg ha−1 year−1) with a slight increasing trend in the future. The spatially averaged EPs for these areas are 3519, 3432, 3557, 3605, 3752, and 3583 kg ha−1 year−1 for current site potential (2000–2008 average), 2020, 2030, 2040, 2050, and 2099, respectively. Therefore, the identified potential biofuel feedstock areas will likely continue to be sustainable for future biofuel development. On the other hand, grasslands identified as having no biofuel potential in the drier western part of the GPRB would be expected to stay unproductive in the future (spatially averaged EPs are 1822, 1691, 1896, 2306, 1994, and 2169 kg ha−1 year−1 for site potential, 2020, 2030, 2040, 2050, and 2099). These areas should continue to be unsuitable for biofuel feedstock development in the future. These future grassland productivity estimation maps can help land managers to understand and adapt to the expected changes in future EP in the GPRB and to assess the future sustainability and feasibility of potential biofuel feedstock areas.

  4. Advanced biofuel production in microbes.

    PubMed

    Peralta-Yahya, Pamela P; Keasling, Jay D

    2010-02-01

    The cost-effective production of biofuels from renewable materials will begin to address energy security and climate change concerns. Ethanol, naturally produced by microorganisms, is currently the major biofuel in the transportation sector. However, its low energy content and incompatibility with existing fuel distribution and storage infrastructure limits its economic use in the future. Advanced biofuels, such as long chain alcohols and isoprenoid- and fatty acid-based biofuels, have physical properties that more closely resemble petroleum-derived fuels, and as such are an attractive alternative for the future supplementation or replacement of petroleum-derived fuels. Here, we review recent developments in the engineering of metabolic pathways for the production of known and potential advanced biofuels by microorganisms. We concentrate on the metabolic engineering of genetically tractable organisms such as Escherichia coli and Saccharomyces cerevisiae for the production of these advanced biofuels. PMID:20084640

  5. Fuelling the future: microbial engineering for the production of sustainable biofuels.

    PubMed

    Liao, James C; Mi, Luo; Pontrelli, Sammy; Luo, Shanshan

    2016-05-01

    Global climate change linked to the accumulation of greenhouse gases has caused concerns regarding the use of fossil fuels as the major energy source. To mitigate climate change while keeping energy supply sustainable, one solution is to rely on the ability of microorganisms to use renewable resources for biofuel synthesis. In this Review, we discuss how microorganisms can be explored for the production of next-generation biofuels, based on the ability of bacteria and fungi to use lignocellulose; through direct CO2 conversion by microalgae; using lithoautotrophs driven by solar electricity; or through the capacity of microorganisms to use methane generated from landfill. Furthermore, we discuss how to direct these substrates to the biosynthetic pathways of various fuel compounds and how to optimize biofuel production by engineering fuel pathways and central metabolism. PMID:27026253

  6. Cyanobacterial biofuel production.

    PubMed

    Machado, Iara M P; Atsumi, Shota

    2012-11-30

    The development of new technologies for production of alternative fuel became necessary to circumvent finite petroleum resources, associate rising costs, and environmental concerns due to rising fossil fuel CO? emissions. Several alternatives have been proposed to develop a sustainable industrial society and reduce greenhouse emissions. The idea of biological conversion of CO? to fuel and chemicals is receiving increased attention. In particular, the direct conversion of CO? with solar energy to biofuel by photosynthetic microorganisms such as microalgae and cyanobacteria has several advantages compared to traditional biofuel production from plant biomass. Photosynthetic microorganisms have higher growth rates compared with plants, and the production systems can be based on non-arable land. The advancement of synthetic biology and genetic manipulation has permitted engineering of cyanobacteria to produce non-natural chemicals typically not produced by these organisms in nature. This review addresses recent publications that utilize different approaches involving engineering cyanobacteria for production of high value chemicals including biofuels. PMID:22446641

  7. Economics of Current and Future Biofuels

    SciTech Connect

    Tao, L.; Aden, A.

    2009-06-01

    This work presents detailed comparative analysis on the production economics of both current and future biofuels, including ethanol, biodiesel, and butanol. Our objectives include demonstrating the impact of key parameters on the overall process economics (e.g., plant capacity, raw material pricing, and yield) and comparing how next-generation technologies and fuels will differ from today's technologies. The commercialized processes and corresponding economics presented here include corn-based ethanol, sugarcane-based ethanol, and soy-based biodiesel. While actual full-scale economic data are available for these processes, they have also been modeled using detailed process simulation. For future biofuel technologies, detailed techno-economic data exist for cellulosic ethanol from both biochemical and thermochemical conversion. In addition, similar techno-economic models have been created for n-butanol production based on publicly available literature data. Key technical and economic challenges facing all of these biofuels are discussed.

  8. Synthetic Biology Guides Biofuel Production

    PubMed Central

    Connor, Michael R.; Atsumi, Shota

    2010-01-01

    The advancement of microbial processes for the production of renewable liquid fuels has increased with concerns about the current fuel economy. The development of advanced biofuels in particular has risen to address some of the shortcomings of ethanol. These advanced fuels have chemical properties similar to petroleum-based liquid fuels, thus removing the need for engine modification or infrastructure redesign. While the productivity and titers of each of these processes remains to be improved, progress in synthetic biology has provided tools to guide the engineering of these processes through present and future challenges. PMID:20827393

  9. Metabolomics of Clostridial Biofuel Production

    SciTech Connect

    Rabinowitz, Joshua D; Aristilde, Ludmilla; Amador-Noguez, Daniel

    2015-09-08

    Members of the genus Clostridium collectively have the ideal set of the metabolic capabilities for fermentative biofuel production: cellulose degradation, hydrogen production, and solvent excretion. No single organism, however, can effectively convert cellulose into biofuels. Here we developed, using metabolomics and isotope tracers, basic science knowledge of Clostridial metabolism of utility for future efforts to engineer such an organism. In glucose fermentation carried out by the biofuel producer Clostridium acetobutylicum, we observed a remarkably ordered series of metabolite concentration changes as the fermentation progressed from acidogenesis to solventogenesis. In general, high-energy compounds decreased while low-energy species increased during solventogenesis. These changes in metabolite concentrations were accompanied by large changes in intracellular metabolic fluxes, with pyruvate directed towards acetyl-CoA and solvents instead of oxaloacetate and amino acids. Thus, the solventogenic transition involves global remodeling of metabolism to redirect resources from biomass production into solvent production. In contrast to C. acetobutylicum, which is an avid fermenter, C. cellulolyticum metabolizes glucose only slowly. We find that glycolytic intermediate concentrations are radically different from fast fermenting organisms. Associated thermodynamic and isotope tracer analysis revealed that the full glycolytic pathway in C. cellulolyticum is reversible. This arises from changes in cofactor utilization for phosphofructokinase and an alternative pathway from phosphoenolpyruvate to pyruvate. The net effect is to increase the high-energy phosphate bond yield of glycolysis by 150% (from 2 to 5) at the expense of lower net flux. Thus, C. cellulolyticum prioritizes glycolytic energy efficiency over speed. Degradation of cellulose results in other sugars in addition to glucose. Simultaneous feeding of stable isotope-labeled glucose and unlabeled pentose sugars (xylose or arabinose) to C. acetobutylicum revealed that, as expected, glucose was preferred, with the pentose sugar selectively assimilated into the pentose phosphate pathway (PPP). Simultaneous feeding of xylose and arabinose revealed an unexpected hierarchy among these pentose sugars, with arabinose utilized preferentially over xylose. Pentose catabolism occurred via the phosphoketolase pathway (PKP), an alternative route of pentose catabolism that directly converts xylulose-5-phosphate into acetyl-phosphate and glyceraldehyde-3-phosphate. Taken collectively, these findings reveal two hierarchies in Clostridial pentose metabolism: xylose is subordinate to arabinose, and the PPP is used less than the PKP. Thus, in addition to massively expanding the available data on Clostridial metabolism, we identified three key regulatory points suitable for targeting in future bioengineering efforts: phosphofructokinase for enhancing fermentation, the pyruvate-oxaloacetate node for controlling solventogenesis, and the phosphoketolase reaction for driving pentose catabolism.

  10. Environmental impacts of biofuel production and use

    EPA Science Inventory

    The 2007 Energy Independence and Security Act (EISA) required a significant increase in the production and use of renewable fuels. Given the current state of technology and infrastructure, nearly all of the projected volume of biofuel consumption over the foreseeable future is ex...

  11. Future of Liquid Biofuels for APEC Economies

    SciTech Connect

    Milbrandt, A.; Overend, R. P.

    2008-05-01

    This project was initiated by APEC Energy Working Group (EWG) to maximize the energy sector's contribution to the region's economic and social well-being through activities in five areas of strategic importance including liquid biofuels production and development.

  12. WATER IMPLICATIONS OF BIOFUELS PRODUCTION

    EPA Science Inventory

    Presentation requested by the National Academy of Science (NAS) for a Colloquium on Water Quality Implications of Biofuels Production, to be held at the NAS in Washington, D.C. on July 12, 2007. This presentation will address the influence of ethanol on hydrocarbon plumes and th...

  13. Growing duckweed for biofuel production: a review.

    PubMed

    Cui, W; Cheng, J J

    2015-01-01

    Duckweed can be utilised to produce ethanol, butanol and biogas, which are promising alternative energy sources to minimise dependence on limited crude oil and natural gas. The advantages of this aquatic plant include high rate of nutrient (nitrogen and phosphorus) uptake, high biomass yield and great potential as an alternative feedstock for the production of fuel ethanol, butanol and biogas. The objective of this article is to review the published research on growing duckweed for the production of the biofuels, especially starch enrichment in duckweed plants. There are mainly two processes affecting the accumulation of starch in duckweed biomass: photosynthesis for starch generation and metabolism-related starch consumption. The cost of stimulating photosynthesis is relatively high based on current technologies. Considerable research efforts have been made to inhibit starch degradation. Future research need in this area includes duckweed selection, optimisation of duckweed biomass production, enhancement of starch accumulation in duckweeds and use of duckweeds for production of various biofuels. PMID:24985498

  14. Thermoacidophilic proteins for biofuel production.

    PubMed

    Hess, Matthias

    2008-09-01

    Growing concerns about global climate change and energy dependence have led to an increased effort to reduce carbon emissions. A considerable reduction could be achieved by using biofuels from lignocellulosic biomass instead of fossil fuels. One major bottleneck of biofuel production from lignocellulose is the availability of efficient and inexpensive biocatalysts (i.e. alcohol dehydrogenases, cellulases and esterases) that are active and stable at high temperatures and low pH values. Although heterologous gene expression is used effectively to obtain recombinant proteins derived from mesophiles, the production of thermoacidophilic proteins is often unsuccessful. Some of the reasons for this failure and potential solutions for an increased production of novel extremophilic biocatalysts are discussed here. PMID:18691890

  15. Toward nitrogen neutral biofuel production.

    PubMed

    Huo, Yi-Xin; Wernick, David G; Liao, James C

    2012-06-01

    Environmental concerns and an increasing global energy demand have spurred scientific research and political action to deliver large-scale production of liquid biofuels. Current biofuel processes and developing approaches have focused on closing the carbon cycle by biological fixation of atmospheric carbon dioxide and conversion of biomass to fuels. To date, these processes have relied on fertilizer produced by the energy-intensive Haber-Bosch process, and have not addressed the global nitrogen cycle and its environmental implications. Recent developments to convert protein to fuel and ammonia may begin to address these problems. In this scheme, recycling ammonia to either plant or algal feedstocks reduces the demand for synthetic fertilizer supplementation. Further development of this technology will realize its advantages of high carbon fixation rates, inexpensive and simple feedstock processing, in addition to reduced fertilizer requirements. PMID:22054644

  16. Towards sustainable production of biofuels from microalgae.

    PubMed

    Patil, Vishwanath; Tran, Khanh-Quang; Giselrød, Hans Ragnar

    2008-06-01

    Renewable and carbon neutral biofuels are necessary for environmental and economic sustainability. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Microalgal biofuels are a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. This paper aims to analyze and promote integration approaches for sustainable microalgal biofuel production to meet the energy and environmental needs of the society. The emphasis is on hydrothermal liquefaction technology for direct conversion of algal biomass to liquid fuel. PMID:19325798

  17. Towards Sustainable Production of Biofuels from Microalgae

    PubMed Central

    Patil, Vishwanath; Tran, Khanh-Quang; Giselrød, Hans Ragnar

    2008-01-01

    Renewable and carbon neutral biofuels are necessary for environmental and economic sustainability. The viability of the first generation biofuels production is however questionable because of the conflict with food supply. Microalgal biofuels are a viable alternative. The oil productivity of many microalgae exceeds the best producing oil crops. This paper aims to analyze and promote integration approaches for sustainable microalgal biofuel production to meet the energy and environmental needs of the society. The emphasis is on hydrothermal liquefaction technology for direct conversion of algal biomass to liquid fuel. PMID:19325798

  18. Multiphase Flow Modeling of Biofuel Production Processes

    SciTech Connect

    D. Gaston; D. P. Guillen; J. Tester

    2011-06-01

    As part of the Idaho National Laboratory's (INL's) Secure Energy Initiative, the INL is performing research in areas that are vital to ensuring clean, secure energy supplies for the future. The INL Hybrid Energy Systems Testing (HYTEST) Laboratory is being established to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. HYTEST involves producing liquid fuels in a Hybrid Energy System (HES) by integrating carbon-based (i.e., bio-mass, oil-shale, etc.) with non-carbon based energy sources (i.e., wind energy, hydro, geothermal, nuclear, etc.). Advances in process development, control and modeling are the unifying vision for HES. This paper describes new modeling tools and methodologies to simulate advanced energy processes. Needs are emerging that require advanced computational modeling of multiphase reacting systems in the energy arena, driven by the 2007 Energy Independence and Security Act, which requires production of 36 billion gal/yr of biofuels by 2022, with 21 billion gal of this as advanced biofuels. Advanced biofuels derived from microalgal biomass have the potential to help achieve the 21 billion gal mandate, as well as reduce greenhouse gas emissions. Production of biofuels from microalgae is receiving considerable interest due to their potentially high oil yields (around 600 gal/acre). Microalgae have a high lipid content (up to 50%) and grow 10 to 100 times faster than terrestrial plants. The use of environmentally friendly alternatives to solvents and reagents commonly employed in reaction and phase separation processes is being explored. This is accomplished through the use of hydrothermal technologies, which are chemical and physical transformations in high-temperature (200-600 C), high-pressure (5-40 MPa) liquid or supercritical water. Figure 1 shows a simplified diagram of the production of biofuels from algae. Hydrothermal processing has significant advantages over other biomass processing methods with respect to separations. These 'green' alternatives employ a hybrid medium that, when operated supercritically, offers the prospect of tunable physicochemical properties. Solubility can be rapidly altered and phases partitioned selectively to precipitate or dissolve certain components by altering temperature or pressure in the near-critical region. The ability to tune the solvation properties of water in the highly compressible near-critical region facilitates partitioning of products or by-products into separate phases to separate and purify products. Since most challenges related to lipid extraction are associated with the industrial scale-up of integrated extraction systems, the new modeling capability offers the prospect of addressing previously untenable scaling issues.

  19. Coupling of Algal Biofuel Production with Wastewater

    PubMed Central

    Panwar, Amit; Bisht, Tara Singh; Tamta, Sushma

    2014-01-01

    Microalgae have gained enormous consideration from scientific community worldwide emerging as a viable feedstock for a renewable energy source virtually being carbon neutral, high lipid content, and comparatively more advantageous to other sources of biofuels. Although microalgae are seen as a valuable source in majority part of the world for production of biofuels and bioproducts, still they are unable to accomplish sustainable large-scale algal biofuel production. Wastewater has organic and inorganic supplements required for algal growth. The coupling of microalgae with wastewater is an effective way of waste remediation and a cost-effective microalgal biofuel production. In this review article, we will primarily discuss the possibilities and current scenario regarding coupling of microalgal cultivation with biofuel production emphasizing recent progress in this area. PMID:24982930

  20. Systems-Level Synthetic Biology for Advanced Biofuel Production

    SciTech Connect

    Ruffing, Anne; Jensen, Travis J.; Strickland, Lucas Marshall; Meserole, Stephen; Tallant, David

    2015-03-01

    Cyanobacteria have been shown to be capable of producing a variety of advanced biofuels; however, product yields remain well below those necessary for large scale production. New genetic tools and high throughput metabolic engineering techniques are needed to optimize cyanobacterial metabolisms for enhanced biofuel production. Towards this goal, this project advances the development of a multiple promoter replacement technique for systems-level optimization of gene expression in a model cyanobacterial host: Synechococcus sp. PCC 7002. To realize this multiple-target approach, key capabilities were developed, including a high throughput detection method for advanced biofuels, enhanced transformation efficiency, and genetic tools for Synechococcus sp. PCC 7002. Moreover, several additional obstacles were identified for realization of this multiple promoter replacement technique. The techniques and tools developed in this project will help to enable future efforts in the advancement of cyanobacterial biofuels.

  1. Modifying plants for biofuel and biomaterial production.

    PubMed

    Furtado, Agnelo; Lupoi, Jason S; Hoang, Nam V; Healey, Adam; Singh, Seema; Simmons, Blake A; Henry, Robert J

    2014-12-01

    The productivity of plants as biofuel or biomaterial crops is established by both the yield of plant biomass per unit area of land and the efficiency of conversion of the biomass to biofuel. Higher yielding biofuel crops with increased conversion efficiencies allow production on a smaller land footprint minimizing competition with agriculture for food production and biodiversity conservation. Plants have traditionally been domesticated for food, fibre and feed applications. However, utilization for biofuels may require the breeding of novel phenotypes, or new species entirely. Genomics approaches support genetic selection strategies to deliver significant genetic improvement of plants as sources of biomass for biofuel manufacture. Genetic modification of plants provides a further range of options for improving the composition of biomass and for plant modifications to assist the fabrication of biofuels. The relative carbohydrate and lignin content influences the deconstruction of plant cell walls to biofuels. Key options for facilitating the deconstruction leading to higher monomeric sugar release from plants include increasing cellulose content, reducing cellulose crystallinity, and/or altering the amount or composition of noncellulosic polysaccharides or lignin. Modification of chemical linkages within and between these biomass components may improve the ease of deconstruction. Expression of enzymes in the plant may provide a cost-effective option for biochemical conversion to biofuel. PMID:25431201

  2. The California Biomass Crop Adoption Model estimates biofuel feedstock crop production across diverse agro-ecological zones within the state, under different future climates

    NASA Astrophysics Data System (ADS)

    Kaffka, S.; Jenner, M.; Bucaram, S.; George, N.

    2012-12-01

    Both regulators and businesses need realistic estimates for the potential production of biomass feedstocks for biofuels and bioproducts. This includes the need to understand how climate change will affect mid-tem and longer-term crop performance and relative advantage. The California Biomass Crop Adoption Model is a partial mathematical programming optimization model that estimates the profit level needed for new crop adoption, and the crop(s) displaced when a biomass feedstock crop is added to the state's diverse set of cropping systems, in diverse regions of the state. Both yield and crop price, as elements of profit, can be varied. Crop adoption is tested against current farmer preferences derived from analysis of 10 years crop production data for all crops produced in California, collected by the California Department of Pesticide Regulation. Analysis of this extensive data set resulted in 45 distinctive, representative farming systems distributed across the state's diverse agro-ecological regions. Estimated yields and water use are derived from field trials combined with crop simulation, reported elsewhere. Crop simulation is carried out under different weather and climate assumptions. Besides crop adoption and displacement, crop resource use is also accounted, derived from partial budgets used for each crop's cost of production. Systematically increasing biofuel crop price identified areas of the state where different types of crops were most likely to be adopted. Oilseed crops like canola that can be used for biodiesel production had the greatest potential to be grown in the Sacramento Valley and other northern regions, while sugar beets (for ethanol) had the greatest potential in the northern San Joaquin Valley region, and sweet sorghum in the southern San Joaquin Valley. Up to approximately 10% of existing annual cropland in California was available for new crop adoption. New crops are adopted if the entire cropping system becomes more profitable. In particular, canola production resulted in less overall water use but increased farm profits. Most crop substitutions were resource neutral. If future climate is drier, more winter annual crops like canola are likely to be adopted. Crop displacement is also important for determining market-mediated effects of biomass crop production. Correctly estimating crop displacement at the local scale greatly improves upon estimates for indirect land use change derived from the macro-scale PE and CGE models currently used by US EPA and the California Air Resources Board.

  3. Plant sciences and biofuels production

    SciTech Connect

    Ranney, J.W.; Cushman, J.H.

    1987-04-01

    Integrating the production of lignocellulosic energy crops with conversion into efficient biofuel pathways requires the identification and prioritization of plant qualities that affect the conversion processes. When desirable or undesirable characteristics have been identified, potential crop species must be evaluated to determine how much genetic improvement is possible while maintaining a thriving fast-growing plant. Lignin, as an example, can be important in both thermochemical and biochemical conversion systems. Lignin's chemical composition is complex and varies among species. Lignin is energetically expensive for plants to produce, and it plays an important role in plant viability. To improve biomass feedstocks, lignin may be desired in increased or decreased amounts depending on the fuel pathway involved. Changes in chemical composition may also be desirable. The lignin component of biomass feedstocks can be significantly affected, both in amount and in chemical composition, by species selection. Changing lignin content or chemical composition of a species is possible but will be more difficult, more expensive, and may affect plant growth and survival. Other biomass components are similar. Such considerations will strongly affect the choice and efficiency of breeding and bioengineering strategies. The selection of traits for improvement in energy crops is an important decision which must be made by plant scientists and investigators developing conversion technologies working as a team. 5 figs.

  4. Constructed wetlands as biofuel production systems

    NASA Astrophysics Data System (ADS)

    Liu, Dong; Wu, Xu; Chang, Jie; Gu, Baojing; Min, Yong; Ge, Ying; Shi, Yan; Xue, Hui; Peng, Changhui; Wu, Jianguo

    2012-03-01

    Clean biofuel production is an effective way to mitigate global climate change and energy crisis. Progress has been made in reducing greenhouse-gas (GHG) emissions and nitrogen fertilizer consumption through biofuel production. Here we advocate an alternative approach that efficiently produces cellulosic biofuel and greatly reduces GHG emissions using waste nitrogen through wastewater treatment with constructed wetlands in China. Our combined experimental and literature data demonstrate that the net life-cycle energy output of constructed wetlands is higher than that of corn, soybean, switchgrass, low-input high-diversity grassland and algae systems. Energy output from existing constructed wetlands is ~237% of the input for biofuel production and can be enhanced through optimizing the nitrogen supply, hydrologic flow patterns and plant species selection. Assuming that all waste nitrogen in China could be used by constructed wetlands, biofuel production can account for 6.7% of national gasoline consumption. We also find that constructed wetlands have a greater GHG reduction than the existing biofuel production systems in a full life-cycle analysis. This alternative approach is worth pursuing because of its great potential for straightforward operation, its economic competitiveness and many ecological benefits.

  5. Impacts of Climate Change on Biofuels Production

    SciTech Connect

    Melillo, Jerry M.

    2014-04-30

    The overall goal of this research project was to improve and use our biogeochemistry model, TEM, to simulate the effects of climate change and other environmental changes on the production of biofuel feedstocks. We used the improved version of TEM that is coupled with the economic model, EPPA, a part of MIT’s Earth System Model, to explore how alternative uses of land, including land for biofuels production, can help society meet proposed climate targets. During the course of this project, we have made refinements to TEM that include development of a more mechanistic plant module, with improved ecohydrology and consideration of plant-water relations, and a more detailed treatment of soil nitrogen dynamics, especially processes that add or remove nitrogen from ecosystems. We have documented our changes to TEM and used the model to explore the effects on production in land ecosystems, including changes in biofuels production.

  6. A resilience perspective on biofuel production.

    PubMed

    Mu, Dongyan; Seager, Thomas P; Rao, P Suresh C; Park, Jeryang; Zhao, Fu

    2011-07-01

    The recent investment boom and collapse of the corn ethanol industry calls into question the long-term sustainability of traditional approaches to biofuel technologies. Compared with petroleum-based transportation fuels, biofuel production systems are more closely connected to complex and variable natural systems. Especially as biofeedstock production itself becomes more independent of fossil fuel-based supports, stochasticity will become an increasingly important, inherent feature of biofuel feedstock production systems. Accordingly, a fundamental change in design philosophy is necessary to ensure the long-term viability of the biofuels industry. To respond effectively to unexpected disruptions, the new approach will require systems to be designed for resilience (indicated by diversity, efficiency, cohesion, and adaptability) rather than more narrowly defined measures of efficiency. This paper addresses important concepts in the design of coupled engineering-ecological systems (resistance, resilience, adaptability, and transformability) and examines biofuel conversion technologies from a resilience perspective. Conversion technologies that can accommodate multiple feedstocks and final products are suggested to enhance the diversity and flexibility of the entire industry. PMID:21309075

  7. Exploring green catalysts for production of biofuels and value added chemicals for renewable and sustainable energy future

    NASA Astrophysics Data System (ADS)

    Budhi, Sridhar

    Porous silica have attracted significant attention in the past few decades due to their unique textural properties. They were extensively investigated for applications in catalysis, separation, environmental remediation and drug delivery. We have investigated the porous metal incorporated silica in the synthetic as well as catalytic perspectives. The synthesis of metal incorporated mesoporous silica via co-condensation such as SBA-15, KIT-5 are still challenging as it involves acidic synthetic route. Synthesis in high acidity conditions affects the incorporation of metal in silica due to high dissolution of metal precursors and breaking of metal oxygen and silica bond. The research presented here demonstrates an efficient way to incorporate metals by addition of diammonium hydrogen phosphate along with metal precursor during the synthesis. The incorporation efficiency has increased 2-3 times with this approach. Catalytic studies were performed to support our hypothesis. Such synthesized molybdenum incorporated mesoporous silica were investigated as catalyst for fast pyrolysis. When molydenum incorporated in silica was used as catalyst for fast pyrolysis of pine, it selectively produced furans (furan, methylfuran and dimethylfuran). Furans are considered value-added chemicals and can be used as a blendstock for diesel/jet grade fuel. The catalyst was very stable to harsh pyrolysis conditions and had a longer life before deactivation when compared with traditional zeolites. Further, this catalyst did not produce aromatic hydrocarbons in significant yields unlike zeolites. The origin of the furans was determined to be biopolymer cellulose and the selectivity for furans are attributed to low catalyst acidity. The effect of silica to alumina ratio (SAR) of beta-zeolite was investigated ranging to elucidate the relationship between the of number of acid sites on product speciation and catalyst deactivation on catalysts supplied by Johnson Matthey. The catalyst with low SAR (more acid sites) produced predominantly aromatic hydrocarbons and olefins with no detectable oxygen containing species. In contrary, the catalyst with high SAR (fewer acid sites) produced a suite of oxygenated products such as furans, phenols and cresols. The coke deposited on each catalyst and the yield of aromatic hydrocarbons were in direct proportion to the number of acid sites. When catalysts were active, the biomass selectivity towards hydrocarbons and amount of coke were constant regardless of SAR.

  8. Omics in Chlamydomonas for Biofuel Production.

    PubMed

    Aucoin, Hanna R; Gardner, Joseph; Boyle, Nanette R

    2016-01-01

    In response to demands for sustainable domestic fuel sources, research into biofuels has become increasingly important. Many challenges face biofuels in their effort to replace petroleum fuels, but rational strain engineering of algae and photosynthetic organisms offers a great deal of promise. For decades, mutations and stress responses in photosynthetic microbiota were seen to result in production of exciting high-energy fuel molecules, giving hope but minor capability for design. However, '-omics' techniques for visualizing entire cell processing has clarified biosynthesis and regulatory networks. Investigation into the promising production behaviors of the model organism C. reinhardtii and its mutants with these powerful techniques has improved predictability and understanding of the diverse, complex interactions within photosynthetic organisms. This new equipment has created an exciting new frontier for high-throughput, predictable engineering of photosynthetically produced carbon-neutral biofuels. PMID:27023246

  9. A literature review of the market effects of federal biofuel policy and recommendations for future policy

    NASA Astrophysics Data System (ADS)

    Ayers, Alex Elgin

    The United States has had a federal biofuels policy since the 1970s. The purpose of this policy was to help the development of a biofuel industry during a time of high fuel prices in order to provide a domestic alternative to expensive foreign oil. Later the policy was changed to help lower the environmental impact caused by conventional fuels. Since that time the industry has grown and currently produces around 15 billion gallons of biofuels every year. The current federal biofuel policy is largely based on one program, the Renewable Fuel Standard (RFS), which mandates the production and blending of several different classes of biofuels and provides a form of subsidy to the biofuel industry. This paper examines the market effects of the federal biofuel policy and provides recommendations for improving the policy to counteract any negative effects. Federal biofuel policy has many far-reaching market effects. Some are easily calculable through expenditures and lost revenues, while others are harder to quantify because their full effects are not yet known. By evaluating these market effects, this paper will provide ample evidence that the federal biofuels policy needs to change, and will show what effects these changes could induce. The biofuels industry largely owes its existence to government policies, however as the research shows the industry can now stand on its own. This paper will examine what will happen if the federal policy is eliminated and what the future of the biofuels industry could hold. Based on these examinations, it is unlikely that the industry needs further government support and policies should be adjusted in light of this.

  10. Health impact assessment of liquid biofuel production.

    PubMed

    Fink, Rok; Medved, Sašo

    2013-01-01

    Bioethanol and biodiesel as potential substitutes for fossil fuels in the transportation sector have been analyzed for environmental suitability. However, there could be impacts on human health during the production, therefore adverse health effects have to be analyzed. The aim of this study is to analyze to what health risk factors humans are exposed to in the production of biofuels and what the size of the health effects is. A health impact assessment expressed as disability adjusted life years (DALYs) was conducted in SimaPro 7.1 software. The results show a statistically significant lower carcinogenic impact of biofuels (p < 0.05) than fossil fuels. Meanwhile, the impact of organic respirable compounds is smaller for fossil fuels (p < 0.05) than for biofuels. Analysis of inorganic compounds like PM₁₀,₂.₅, SO₂ or NO(x) shows some advantages of sugar beet bioethanol and soybean biodiesel production (p < 0.05), although production of sugarcane bioethanol shows larger impacts of respirable inorganic compounds than for fossil fuels (p < 0.001). Although liquid biofuels are made of renewable energy sources, this does not necessary mean that they do not represent any health hazards. PMID:22774773

  11. Closed photo-bioreactors as tools for biofuel production.

    PubMed

    Lehr, Florian; Posten, Clemens

    2009-06-01

    Production of biofuels from microalgae is a promising sustainable option for the future. Unfortunately, until now production of algae biomass is too expensive owing to costly plant designs or high demand of auxiliary energy. These problems are addressed in recent developments. Basic ideas that are followed in different novel pilot plants are efficient mixing, high light dilution via large external surfaces or internal light conducting structures and gas transport via membranes. Other attempts are directed towards cheaper constructions. These endeavours have brought microalgal biofuel production closer to economic viability as has been shown in some pilot plants. But until now, these plants operate only on a small area and a limited time frame, making economic assessment difficult. The next years will show, whether these promises can be kept on a pure commercial basis for a whole process chain from algae cultivation to oil extraction during a whole year and on a real hectare. PMID:19501503

  12. Plant biotechnology for lignocellulosic biofuel production.

    PubMed

    Li, Quanzi; Song, Jian; Peng, Shaobing; Wang, Jack P; Qu, Guan-Zheng; Sederoff, Ronald R; Chiang, Vincent L

    2014-12-01

    Lignocelluloses from plant cell walls are attractive resources for sustainable biofuel production. However, conversion of lignocellulose to biofuel is more expensive than other current technologies, due to the costs of chemical pretreatment and enzyme hydrolysis for cell wall deconstruction. Recalcitrance of cell walls to deconstruction has been reduced in many plant species by modifying plant cell walls through biotechnology. These results have been achieved by reducing lignin content and altering its composition and structure. Reduction of recalcitrance has also been achieved by manipulating hemicellulose biosynthesis and by overexpression of bacterial enzymes in plants to disrupt linkages in the lignin-carbohydrate complexes. These modified plants often have improved saccharification yield and higher ethanol production. Cell wall-degrading (CWD) enzymes from bacteria and fungi have been expressed at high levels in plants to increase the efficiency of saccharification compared with exogenous addition of cellulolytic enzymes. In planta expression of heat-stable CWD enzymes from bacterial thermophiles has made autohydrolysis possible. Transgenic plants can be engineered to reduce recalcitrance without any yield penalty, indicating that successful cell wall modification can be achieved without impacting cell wall integrity or plant development. A more complete understanding of cell wall formation and structure should greatly improve lignocellulosic feedstocks and reduce the cost of biofuel production. PMID:25330253

  13. Cyanobacteria as a Platform for Biofuel Production

    PubMed Central

    Nozzi, Nicole E.; Oliver, John W. K.; Atsumi, Shota

    2013-01-01

    Cyanobacteria have great potential as a platform for biofuel production because of their fast growth, ability to fix carbon dioxide gas, and their genetic tractability. Furthermore they do not require fermentable sugars or arable land for growth and so competition with cropland would be greatly reduced. In this perspective we discuss the challenges and areas for improvement most pertinent for advancing cyanobacterial fuel production, including: improving genetic parts, carbon fixation, metabolic flux, nutrient requirements on a large scale, and photosynthetic efficiency using natural light. PMID:25022311

  14. Biofuels Fuels Technology Pathway Options for Advanced Drop-in Biofuels Production

    SciTech Connect

    Kevin L Kenney

    2011-09-01

    Advanced drop-in hydrocarbon biofuels require biofuel alternatives for refinery products other than gasoline. Candidate biofuels must have performance characteristics equivalent to conventional petroleum-based fuels. The technology pathways for biofuel alternatives also must be plausible, sustainable (e.g., positive energy balance, environmentally benign, etc.), and demonstrate a reasonable pathway to economic viability and end-user affordability. Viable biofuels technology pathways must address feedstock production and environmental issues through to the fuel or chemical end products. Potential end products include compatible replacement fuel products (e.g., gasoline, diesel, and JP8 and JP5 jet fuel) and other petroleum products or chemicals typically produced from a barrel of crude. Considering the complexity and technology diversity of a complete biofuels supply chain, no single entity or technology provider is capable of addressing in depth all aspects of any given pathway; however, all the necessary expert entities exist. As such, we propose the assembly of a team capable of conducting an in-depth technology pathway options analysis (including sustainability indicators and complete LCA) to identify and define the domestic biofuel pathways for a Green Fleet. This team is not only capable of conducting in-depth analyses on technology pathways, but collectively they are able to trouble shoot and/or engineer solutions that would give industrial technology providers the highest potential for success. Such a team would provide the greatest possible down-side protection for high-risk advanced drop-in biofuels procurement(s).

  15. The potential of sustainable algal biofuel production using wastewater resources.

    PubMed

    Pittman, Jon K; Dean, Andrew P; Osundeko, Olumayowa

    2011-01-01

    The potential of microalgae as a source of renewable energy has received considerable interest, but if microalgal biofuel production is to be economically viable and sustainable, further optimization of mass culture conditions are needed. Wastewaters derived from municipal, agricultural and industrial activities potentially provide cost-effective and sustainable means of algal growth for biofuels. In addition, there is also potential for combining wastewater treatment by algae, such as nutrient removal, with biofuel production. Here we will review the current research on this topic and discuss the potential benefits and limitations of using wastewaters as resources for cost-effective microalgal biofuel production. PMID:20594826

  16. Limitation of Biofuel Production in Europe from the Forest Market

    NASA Astrophysics Data System (ADS)

    Leduc, Sylvain; Wetterlund, Elisabeth; Dotzauer, Erik; Kindermann, Georg

    2013-04-01

    The European Union has set a 10% target for the share of biofuel in the transportation sector to be met by 2020. To reach this target, second generation biofuel is expected to replace 3 to 5% of the transport fossil fuel consumption. But the competition on the feedstock is an issue and makes the planning for the second generation biofuel plant a challenge. Moreover, no commercial second generation biofuel production plant is under operation, but if reaching commercial status, this type of production plants are expected to become very large. In order to minimize the tranportation costs and to takle the competetion for the feedstock against the existing woody based industries, the geographical location of biofuel production plants becomes an issue. This study investigates the potential of second generation biofuel economically feasible in Europe by 2020 in regards with the competition for the feedsstock with the existing woody biomass based industries (CHP, pulp and paper mills, sawmills...). To assess the biofuel potential in Europe, a techno-economic, geographically explicit model, BeWhere, is used. It determines the optimal locations of bio-energy production plants by minimizing the costs and CO2 emissions of the entire supply chain. The existing woody based industries have to first meet their wood demand, and if the amount of wood that remains is suficiant, new bio-energy production plants if any can be set up. Preliminary results show that CHP plants are preferably chosen over biofuel production plants. Strong biofuel policy support is needed in order to consequently increase the biofuel production in Europe. The carbon tax influences the emission reduction to a higher degree than the biofuel support. And the potential of second generation biofuel would at most reach 3% of the European transport fuel if the wood demand does not increase from 2010.

  17. Metabolic Engineering for Advanced Biofuels Production from Escherichia coli

    PubMed Central

    Atsumi, Shota; Liao, James C.

    2008-01-01

    Summary Global energy and environmental problems have stimulated increasing efforts towards synthesizing liquid biofuels as transportation energy. Compared to the traditional biofuel, ethanol, advanced biofuels should offer advantages such as higher energy density, lower hygroscopicity, lower vapor pressure, and compatibility with existing transportation infrastructure. However, these fuels are not synthesized economically using native organisms. Metabolic engineering offers an alternative approach in which synthetic pathways are engineered into user friendly hosts for the production of these fuel molecules. These hosts could be readily manipulated to improve the production efficiency. This review summarizes recent progress in the engineering of Escherichia coli to produce advanced biofuels. PMID:18761088

  18. Genetically Engineered Materials for Biofuels Production

    NASA Astrophysics Data System (ADS)

    Raab, Michael

    2012-02-01

    Agrivida, Inc., is an agricultural biotechnology company developing industrial crop feedstocks for the fuel and chemical industries. Agrivida's crops have improved processing traits that enable efficient, low cost conversion of the crops' cellulosic components into fermentable sugars. Currently, pretreatment and enzymatic conversion of the major cell wall components, cellulose and hemicellulose, into fermentable sugars is the most expensive processing step that prevents widespread adoption of biomass in biofuels processes. To lower production costs we are consolidating pretreatment and enzyme production within the crop. In this strategy, transgenic plants express engineered cell wall degrading enzymes in an inactive form, which can be reactivated after harvest. We have engineered protein elements that disrupt enzyme activity during normal plant growth. Upon exposure to specific processing conditions, the engineered enzymes are converted into their active forms. This mechanism significantly lowers pretreatment costs and enzyme loadings (>75% reduction) below those currently available to the industry.

  19. Environmental indicators for sustainable production of algal biofuels

    DOE PAGESBeta

    Efroymson, Rebecca A.; Dale, Virginia H.

    2014-10-01

    For analyzing sustainability of algal biofuels, we identify 16 environmental indicators that fall into six categories: soil quality, water quality and quantity, air quality, greenhouse gas emissions, biodiversity, and productivity. Indicators are selected to be practical, widely applicable, predictable in response, anticipatory of future changes, independent of scale, and responsive to management. Major differences between algae and terrestrial plant feedstocks, as well as their supply chains for biofuel, are highlighted, for they influence the choice of appropriate sustainability indicators. Algae strain selection characteristics do not generally affect which indicators are selected. The use of water instead of soil as themore » growth medium for algae determines the higher priority of water- over soil-related indicators. The proposed set of environmental indicators provides an initial checklist for measures of biofuel sustainability but may need to be modified for particular contexts depending on data availability, goals of the stakeholders, and financial constraints. Ultimately, use of these indicators entails defining sustainability goals and targets in relation to stakeholder values in a particular context and can lead to improved management practices.« less

  20. Environmental indicators for sustainable production of algal biofuels

    SciTech Connect

    Efroymson, Rebecca A.; Dale, Virginia H.

    2014-10-01

    For analyzing sustainability of algal biofuels, we identify 16 environmental indicators that fall into six categories: soil quality, water quality and quantity, air quality, greenhouse gas emissions, biodiversity, and productivity. Indicators are selected to be practical, widely applicable, predictable in response, anticipatory of future changes, independent of scale, and responsive to management. Major differences between algae and terrestrial plant feedstocks, as well as their supply chains for biofuel, are highlighted, for they influence the choice of appropriate sustainability indicators. Algae strain selection characteristics do not generally affect which indicators are selected. The use of water instead of soil as the growth medium for algae determines the higher priority of water- over soil-related indicators. The proposed set of environmental indicators provides an initial checklist for measures of biofuel sustainability but may need to be modified for particular contexts depending on data availability, goals of the stakeholders, and financial constraints. Ultimately, use of these indicators entails defining sustainability goals and targets in relation to stakeholder values in a particular context and can lead to improved management practices.

  1. Environmental indicators for sustainable production of algal biofuels

    SciTech Connect

    Efroymson, Rebecca Ann; Dale, Virginia H

    2014-01-01

    For analyzing sustainability of algal biofuels, we identify 16 environmental indicators that fall into six categories: soil quality, water quality and quantity, air quality, greenhouse gas emissions, biodiversity, and productivity. Indicators are selected to be practical, widely applicable, predictable in response, anticipatory of future changes, independent of scale, and responsive to management. Major differences between algae and terrestrial plant feedstocks, as well as their supply chains for biofuel, are highlighted, for they influence the choice of appropriate sustainability indicators. Algae strain selection characteristics do not generally affect which indicators are selected. The use of water instead of soil as the growth medium for algae determines the higher priority of water- over soil-related indicators. The proposed set of environmental indicators provides an initial checklist for measures of biofuel sustainability but may need to be modified for particular contexts depending on data availability, goals of the stakeholders, and financial constraints. Use of these indicators entails defining sustainability goals and targets in relation to stakeholder values in a particular context and can lead to improved management practices.

  2. Water resources under future scenarios of climate change and biofuel development: A case study for Yakima River basin

    NASA Astrophysics Data System (ADS)

    Demissie, Y. K.

    2013-12-01

    In recent years, biofuel has become an important renewable energy source with a potential to help mitigate climate change. However, agriculture productivity and its potential use for sustainable production of biofuel are strongly dependent on climate and water conditions that may change in response to future changes in climate and/or socio-economic conditions. For instant in 2012, the US has experienced the most severe drought that results in a 12% decrease in corn production - the main feedstock used for biofuel in US - indicating the vulnerability of biofuel development and policies to change in climate and associated extreme weather conditions. To understand this interrelationship and the combined effects of increased biofuel production and climate change on regional and local water resources, we have applied a SWAT watershed model which integrates future scenarios of climate change and biofuel development and simulates the associated impacts on watershed hydrology, water quality, soil erosion, and agriculture productivity. The study is applied to the Yakima River basin (YRB), which has higher biomass resources in Washington State and represents a region where forestry and agriculture intersect with considerable water shortage as well as spatial variations in annual precipitation. Unlike earlier studies, which commonly define biofuel and climate change scenarios independently, in this study the decision on alternative biofuel feedstock mixes and associated change in land use and management take into account the anticipated climate change. The resulted spatial and temporal distributions of water budget, nutrient loads, and sediment erosion is analyzed to evaluate the effectiveness of biofuel policies under constraints of climate change and water resources in the region.

  3. An Overview of Algae Biofuel Production and Potential Environmental Impact

    EPA Science Inventory

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas)...

  4. Optimizing root system architecture in biofuel crops for sustainable energy production and soil carbon sequestration

    PubMed Central

    To, Jennifer PC; Zhu, Jinming; Benfey, Philip N

    2010-01-01

    Root system architecture (RSA) describes the dynamic spatial configuration of different types and ages of roots in a plant, which allows adaptation to different environments. Modifications in RSA enhance agronomic traits in crops and have been implicated in soil organic carbon content. Together, these fundamental properties of RSA contribute to the net carbon balance and overall sustainability of biofuels. In this article, we will review recent data supporting carbon sequestration by biofuel crops, highlight current progress in studying RSA, and discuss future opportunities for optimizing RSA for biofuel production and soil carbon sequestration. PMID:21173868

  5. Next-generation biomass feedstocks for biofuel production

    PubMed Central

    Simmons, Blake A; Loque, Dominique; Blanch, Harvey W

    2008-01-01

    The development of second-generation biofuels - those that do not rely on grain crops as inputs - will require a diverse set of feedstocks that can be grown sustainably and processed cost-effectively. Here we review the outlook and challenges for meeting hoped-for production targets for such biofuels in the United States. PMID:19133109

  6. Microbiology of synthesis gas fermentation for biofuel production.

    PubMed

    Henstra, Anne M; Sipma, Jan; Rinzema, Arjen; Stams, Alfons J M

    2007-06-01

    A significant portion of biomass sources like straw and wood is poorly degradable and cannot be converted to biofuels by microorganisms. The gasification of this waste material to produce synthesis gas (or syngas) could offer a solution to this problem, as microorganisms that convert CO and H2) (the essential components of syngas) to multicarbon compounds are available. These are predominantly mesophilic microorganisms that produce short-chain fatty acids and alcohols from CO and H2. Additionally, hydrogen can be produced by carboxydotrophic hydrogenogenic bacteria that convert CO and H2O to H2 and CO2. The production of ethanol through syngas fermentation is already available as a commercial process. The use of thermophilic microorganisms for these processes could offer some advantages; however, to date, few thermophiles are known that grow well on syngas and produce organic compounds. The identification of new isolates that would broaden the product range of syngas fermentations is desirable. Metabolic engineering could be employed to broaden the variety of available products, although genetic tools for such engineering are currently unavailable. Nevertheless, syngas fermenting microorganisms possess advantageous characteristics for biofuel production and hold potential for future engineering efforts. PMID:17399976

  7. An overview of algae biofuel production and potential environmental impact.

    PubMed

    Menetrez, Marc Y

    2012-07-01

    Algae are among the most potentially significant sources of sustainable biofuels in the future of renewable energy. A feedstock with virtually unlimited applicability, algae can metabolize various waste streams (e.g., municipal wastewater, carbon dioxide from industrial flue gas) and produce products with a wide variety of compositions and uses. These products include lipids, which can be processed into biodiesel; carbohydrates, which can be processed into ethanol; and proteins, which can be used for human and animal consumption. Algae are commonly genetically engineered to allow for advantageous process modification or optimization. However, issues remain regarding human exposure to algae-derived toxins, allergens, and carcinogens from both existing and genetically modified organisms (GMOs), as well as the overall environmental impact of GMOs. A literature review was performed to highlight issues related to the growth and use of algal products for generating biofuels. Human exposure and environmental impact issues are identified and discussed, as well as current research and development activities of academic, commercial, and governmental groups. It is hoped that the ideas contained in this paper will increase environmental awareness of issues surrounding the production of algae and will help the algae industry develop to its full potential. PMID:22681590

  8. Risks to global biodiversity from fossil-fuel production exceed those from biofuel production

    SciTech Connect

    Dale, Virginia H; Parish, Esther S; Kline, Keith L

    2015-01-01

    Potential global biodiversity impacts from near-term gasoline production are compared to biofuel, a renewable liquid transportation fuel expected to substitute for gasoline in the near term (i.e., from now until c. 2030). Petroleum exploration activities are projected to extend across more than 5.8 billion ha of land and ocean worldwide (of which 3.1 billion is on land), much of which is in remote, fragile terrestrial ecosystems or off-shore oil fields that would remain relatively undisturbed if not for interest in fossil fuel production. Future biomass production for biofuels is projected to fall within 2.0 billion ha of land, most of which is located in areas already impacted by human activities. A comparison of likely fuel-source areas to the geospatial distribution of species reveals that both energy sources overlap with areas with high species richness and large numbers of threatened species. At the global scale, future petroleum production areas intersect more than double the area and higher total number of threatened species than future biofuel production. Energy options should be developed to optimize provisioning of ecosystem services while minimizing negative effects, which requires information about potential impacts on critical resources. Energy conservation and identifying and effectively protecting habitats with high-conservation value are critical first steps toward protecting biodiversity under any fuel production scenario.

  9. Risks to global biodiversity from fossil-fuel production exceed those from biofuel production

    DOE PAGESBeta

    Dale, Virginia H; Parish, Esther S; Kline, Keith L

    2015-01-01

    Potential global biodiversity impacts from near-term gasoline production are compared to biofuel, a renewable liquid transportation fuel expected to substitute for gasoline in the near term (i.e., from now until c. 2030). Petroleum exploration activities are projected to extend across more than 5.8 billion ha of land and ocean worldwide (of which 3.1 billion is on land), much of which is in remote, fragile terrestrial ecosystems or off-shore oil fields that would remain relatively undisturbed if not for interest in fossil fuel production. Future biomass production for biofuels is projected to fall within 2.0 billion ha of land, most ofmore » which is located in areas already impacted by human activities. A comparison of likely fuel-source areas to the geospatial distribution of species reveals that both energy sources overlap with areas with high species richness and large numbers of threatened species. At the global scale, future petroleum production areas intersect more than double the area and higher total number of threatened species than future biofuel production. Energy options should be developed to optimize provisioning of ecosystem services while minimizing negative effects, which requires information about potential impacts on critical resources. Energy conservation and identifying and effectively protecting habitats with high-conservation value are critical first steps toward protecting biodiversity under any fuel production scenario.« less

  10. Downstream Processing of Synechocystis for Biofuel Production

    NASA Astrophysics Data System (ADS)

    Sheng, Jie

    Lipids and free fatty acids (FFA) from cyanobacterium Synechocystis can be used for biofuel (e.g. biodiesel or renewable diesel) production. In order to utilize and scale up this technique, downstream processes including culturing and harvest, cell disruption, and extraction were studied. Several solvents/solvent systems were screened for lipid extraction from Synechocystis. Chloroform + methanol-based Folch and Bligh & Dyer methods were proved to be "gold standard" for small-scale analysis due to their highest lipid recoveries that were confirmed by their penetration of the cell membranes, higher polarity, and stronger interaction with hydrogen bonds. Less toxic solvents, such as methanol and MTBE, or direct transesterification of biomass (without preextraction step) gave only slightly lower lipid-extraction yields and can be considered for large-scale application. Sustained exposure to high and low temperature extremes severely lowered the biomass and lipid productivity. Temperature stress also triggered changes of lipid quality such as the degree of unsaturation; thus, it affected the productivities and quality of Synechocystis-derived biofuel. Pulsed electric field (PEF) was evaluated for cell disruption prior to lipid extraction. A treatment intensity > 35 kWh/m3 caused significant damage to the plasma membrane, cell wall, and thylakoid membrane, and it even led to complete disruption of some cells into fragments. Treatment by PEF enhanced the potential for the low-toxicity solvent isopropanol to access lipid molecules during subsequent solvent extraction, leading to lower usage of isopropanol for the same extraction efficiency. Other cell-disruption methods also were tested. Distinct disruption effects to the cell envelope, plasma membrane, and thylakoid membranes were observed that were related to extraction efficiency. Microwave and ultrasound had significant enhancement of lipid extraction. Autoclaving, ultrasound, and French press caused significant release of lipid into the medium, which may increase solvent usage and make medium recycling difficult. Production of excreted FFA by mutant Synechocystis has the potential of reducing the complexity of downstream processing. Major problems, such as FFA precipitation and biodegradation by scavengers, account for FFA loss in operation. Even a low concentration of FFA scavengers could consume FFA at a high rate that outpaced FFA production rate. Potential strategies to overcome FFA loss include high pH, adsorptive resin, and sterilization techniques.

  11. Sustainable production of grain crops for biofuels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Grain crops of the Gramineae are grown for their edible, starchy seeds. Their grain is used directly for human food, livestock feed, and as raw material for many industries, including biofuels. Using grain crops for non-food uses affects the amount of food available to the world. Grain-based biofuel...

  12. Integrated microbial processes for biofuels and high value-added products: the way to improve the cost effectiveness of biofuel production.

    PubMed

    da Silva, Teresa Lopes; Gouveia, Lusa; Reis, Alberto

    2014-02-01

    The production of microbial biofuels is currently under investigation, as they are alternative sources to fossil fuels, which are diminishing and their use has a negative impact on the environment. However, so far, biofuels derived from microbes are not economically competitive. One way to overcome this bottleneck is the use of microorganisms to transform substrates into biofuels and high value-added products, and simultaneously taking advantage of the various microbial biomass components to produce other products of interest, as an integrated process. In this way, it is possible to maximize the economic value of the whole process, with the desired reduction of the waste streams produced. It is expected that this integrated system makes the biofuel production economically sustainable and competitive in the near future. This review describes the investigation on integrated microbial processes (based on bacteria, yeast, and microalgal cultivations) that have been experimentally developed, highlighting the importance of this approach as a way to optimize microbial biofuel production process. PMID:24337249

  13. Selection and optimization of microbial hosts for biofuels production.

    PubMed

    Fischer, Curt R; Klein-Marcuschamer, Daniel; Stephanopoulos, Gregory

    2008-11-01

    Currently, the predominant microbially produced biofuel is starch- or sugar-derived ethanol. However, ethanol is not an ideal fuel molecule, and lignocellulosic feedstocks are considerably more abundant than both starch and sugar. Thus, many improvements in both the feedstock and the fuel have been proposed. In this paper, we examine the prospects for bioproduction of four second-generation biofuels (n-butanol, 2-butanol, terpenoids, or higher lipids) from four feedstocks (sugars and starches, lignocellulosics, syngas, and atmospheric carbon dioxide). The principal obstacle to commercial production of these fuels is that microbial catalysts of robust yields, productivities, and titers have yet to be developed. Suitable microbial hosts for biofuel production must tolerate process stresses such as end-product toxicity and tolerance to fermentation inhibitors in order to achieve high yields and titers. We tested seven fast-growing host organisms for tolerance to production stresses, and discuss several metabolic engineering strategies for the improvement of biofuels production. PMID:18655844

  14. Feasibilities of consolidated bioprocessing microbes: from pretreatment to biofuel production.

    PubMed

    Parisutham, Vinuselvi; Kim, Tae Hyun; Lee, Sung Kuk

    2014-06-01

    Lignocelluloses are rich sugar treasures, which can be converted to useful commodities such as biofuel with the help of efficient combination of enzymes and microbes. Although several bioprocessing approaches have been proposed, biofuel production from lignocelluloses is limited because of economically infeasible technologies for pretreatment, saccharification and fermentation. Use of consolidated bioprocessing (CBP) microbes is the most promising method for the cost-effective production of biofuels. However, lignocelluloses are obtained from highly diverse environment and hence are heterogeneous in nature. Therefore, it is necessary to develop and integrate tailor-designed pretreatment processes and efficient microbes that can thrive on many different kinds of biomass. In this review, the progress towards the construction of consolidated bioprocessing microbes, which can efficiently convert heterogeneous lignocellulosic biomass to bioenergy, has been discussed; in addition, the potential and constraints of current bioprocessing technologies for cellulosic biofuel production have been discussed. PMID:24745899

  15. World Biofuels Production Potential Understanding the Challenges to Meeting the U.S. Renewable Fuel Standard

    SciTech Connect

    Sastri, B.; Lee, A.

    2008-09-15

    This study by the U.S. Department of Energy (DOE) estimates the worldwide potential to produce biofuels including biofuels for export. It was undertaken to improve our understanding of the potential for imported biofuels to satisfy the requirements of Title II of the 2007 Energy Independence and Security Act (EISA) in the coming decades. Many other countries biofuels production and policies are expanding as rapidly as ours. Therefore, we modeled a detailed and up-to-date representation of the amount of biofuel feedstocks that are being and can be grown, current and future biofuels production capacity, and other factors relevant to the economic competitiveness of worldwide biofuels production, use, and trade. The Oak Ridge National Laboratory (ORNL) identified and prepared feedstock data for countries that were likely to be significant exporters of biofuels to the U.S. The National Renewable Energy Laboratory (NREL) calculated conversion costs by conducting material flow analyses and technology assessments on biofuels technologies. Brookhaven National Laboratory (BNL) integrated the country specific feedstock estimates and conversion costs into the global Energy Technology Perspectives (ETP) MARKAL (MARKet ALlocation) model. The model uses least-cost optimization to project the future state of the global energy system in five year increments. World biofuels production was assessed over the 2010 to 2030 timeframe using scenarios covering a range U.S. policies (tax credits, tariffs, and regulations), as well as oil prices, feedstock availability, and a global CO{sub 2} price. All scenarios include the full implementation of existing U.S. and selected other countries biofuels policies (Table 4). For the U.S., the most important policy is the EISA Title II Renewable Fuel Standard (RFS). It progressively increases the required volumes of renewable fuel used in motor vehicles (Appendix B). The RFS requires 36 billion (B) gallons (gal) per year of renewable fuels by 2022. Within the mandate, amounts of advanced biofuels, including biomass-based diesel and cellulosic biofuels, are required beginning in 2009. Imported renewable fuels are also eligible for the RFS. Another key U.S. policy is the $1.01 per gal tax credit for producers of cellulosic biofuels enacted as part of the 2008 Farm Bill. This credit, along with the DOE's research, development and demonstration (RD&D) programs, are assumed to enable the rapid expansion of U.S. and global cellulosic biofuels production needed for the U.S. to approach the 2022 RFS goal. While the Environmental Protection Agency (EPA) has yet to issue RFS rules to determine which fuels would meet the greenhouse gas (GHG) reduction and land use restrictions specified in EISA, we assume that cellulosic ethanol, biomass-to-liquid fuels (BTL), sugar-derived ethanol, and fatty acid methyl ester biodiesel would all meet the EISA advanced biofuel requirements. We also assume that enough U.S. corn ethanol would meet EISA's biofuel requirements or otherwise be grandfathered under EISA to reach 15 B gal per year.

  16. Enzymatic deconstruction of xylan for biofuel production

    PubMed Central

    DODD, DYLAN; CANN, ISAAC K. O.

    2010-01-01

    The combustion of fossil-derived fuels has a significant impact on atmospheric carbon dioxide (CO2) levels and correspondingly is an important contributor to anthropogenic global climate change. Plants have evolved photosynthetic mechanisms in which solar energy is used to fix CO2 into carbohydrates. Thus, combustion of biofuels, derived from plant biomass, can be considered a potentially carbon neutral process. One of the major limitations for efficient conversion of plant biomass to biofuels is the recalcitrant nature of the plant cell wall, which is composed mostly of lignocellulosic materials (lignin, cellulose, and hemicellulose). The heteropolymer xylan represents the most abundant hemicellulosic polysaccharide and is composed primarily of xylose, arabinose, and glucuronic acid. Microbes have evolved a plethora of enzymatic strategies for hydrolyzing xylan into its constituent sugars for subsequent fermentation to biofuels. Therefore, microorganisms are considered an important source of biocatalysts in the emerging biofuel industry. To produce an optimized enzymatic cocktail for xylan deconstruction, it will be valuable to gain insight at the molecular level of the chemical linkages and the mechanisms by which these enzymes recognize their substrates and catalyze their reactions. Recent advances in genomics, proteomics, and structural biology have revolutionized our understanding of the microbial xylanolytic enzymes. This review focuses on current understanding of the molecular basis for substrate specificity and catalysis by enzymes involved in xylan deconstruction. PMID:20431716

  17. Microalgae as sustainable renewable energy feedstock for biofuel production.

    PubMed

    Medipally, Srikanth Reddy; Yusoff, Fatimah Md; Banerjee, Sanjoy; Shariff, M

    2015-01-01

    The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties. PMID:25874216

  18. Microalgae as Sustainable Renewable Energy Feedstock for Biofuel Production

    PubMed Central

    Yusoff, Fatimah Md.; Shariff, M.

    2015-01-01

    The world energy crisis and increased greenhouse gas emissions have driven the search for alternative and environmentally friendly renewable energy sources. According to life cycle analysis, microalgae biofuel is identified as one of the major renewable energy sources for sustainable development, with potential to replace the fossil-based fuels. Microalgae biofuel was devoid of the major drawbacks associated with oil crops and lignocelluloses-based biofuels. Algae-based biofuels are technically and economically viable and cost competitive, require no additional lands, require minimal water use, and mitigate atmospheric CO2. However, commercial production of microalgae biodiesel is still not feasible due to the low biomass concentration and costly downstream processes. The viability of microalgae biodiesel production can be achieved by designing advanced photobioreactors, developing low cost technologies for biomass harvesting, drying, and oil extraction. Commercial production can also be accomplished by improving the genetic engineering strategies to control environmental stress conditions and by engineering metabolic pathways for high lipid production. In addition, new emerging technologies such as algal-bacterial interactions for enhancement of microalgae growth and lipid production are also explored. This review focuses mainly on the problems encountered in the commercial production of microalgae biofuels and the possible techniques to overcome these difficulties. PMID:25874216

  19. Future testing opportunities to ensure sustainability of the biofuels industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For the Soil and Plant Analysis Community, development and expansion of biofuels will create many opportunities to provide a wide variety of analytical services. Our objective is to explore potential areas where those services could be marketed to support sustainable development of biofuels. One of ...

  20. Impact of Various Biofuel Feedstock Production Scenarios on Water Quality in the Upper Mississippi River Basin

    NASA Astrophysics Data System (ADS)

    Wu, M.; Demissie, Y.; Yan, E.

    2010-12-01

    The impact of increased biofuel feedstock production on regional water quality was examined. This study focused on the Upper Mississippi River Basin, from which a majority of U.S. biofuel is currently produced. The production of biofuel from both conventional feedstock and cellulosic feedstock will potentially increase in the near future. Historically, this water basin generates the largest nitrogen loading to the waterway in the United States and is often cited as a main contributor to the anoxic zone in the Gulf of Mexico. To obtain a quantitative and spatial estimate of nutrient burdens at the river basin, a SWAT (Soil and Water Assessment Tool) model application was developed. The model was equipped with an updated nutrient cycle feature and modified model parameters to represent current crop and perennial grass yield as a result of advancements in breeding and biotechnology. Various biofuel feedstock production scenarios were developed to assess the potential environmental implications of increased biofuel production through corn, agriculture residue, and perennial cellulosic feedstock (such as Switchgrass). Major factors were analyzed, including land use changes, feedstock types, fertilizer inputs, soil property, and yield. This tool can be used to identify specific regional factors affecting water quality and examine options to meet the requirement for environmental sustainability, thereby mitigating undesirable environmental consequences while strengthening energy security.

  1. Biofuel production from microalgae as feedstock: current status and potential.

    PubMed

    Han, Song-Fang; Jin, Wen-Biao; Tu, Ren-Jie; Wu, Wei-Min

    2015-06-01

    Algal biofuel has become an attractive alternative of petroleum-based fuels in the past decade. Microalgae have been proposed as a feedstock to produce biodiesel, since they are capable of mitigating CO2 emission and accumulating lipids with high productivity. This article is an overview of the updated status of biofuels, especially biodiesel production from microalgae including fundamental research, culture selection and engineering process development; it summarizes research on mathematical and life cycle modeling on algae growth and biomass production; and it updates global efforts of research and development and commercialization attempts. The major challenges are also discussed. PMID:24641484

  2. The potential of C4 grasses for cellulosic biofuel production

    PubMed Central

    van der Weijde, Tim; Alvim Kamei, Claire L.; Torres, Andres F.; Vermerris, Wilfred; Dolstra, Oene; Visser, Richard G. F.; Trindade, Luisa M.

    2013-01-01

    With the advent of biorefinery technologies enabling plant biomass to be processed into biofuel, many researchers set out to study and improve candidate biomass crops. Many of these candidates are C4 grasses, characterized by a high productivity and resource use efficiency. In this review the potential of five C4 grasses as lignocellulosic feedstock for biofuel production is discussed. These include three important field crops—maize, sugarcane and sorghum—and two undomesticated perennial energy grasses—miscanthus and switchgrass. Although all these grasses are high yielding, they produce different products. While miscanthus and switchgrass are exploited exclusively for lignocellulosic biomass, maize, sorghum, and sugarcane are dual-purpose crops. It is unlikely that all the prerequisites for the sustainable and economic production of biomass for a global cellulosic biofuel industry will be fulfilled by a single crop. High and stable yields of lignocellulose are required in diverse environments worldwide, to sustain a year-round production of biofuel. A high resource use efficiency is indispensable to allow cultivation with minimal inputs of nutrients and water and the exploitation of marginal soils for biomass production. Finally, the lignocellulose composition of the feedstock should be optimized to allow its efficient conversion into biofuel and other by-products. Breeding for these objectives should encompass diverse crops, to meet the demands of local biorefineries and provide adaptability to different environments. Collectively, these C4 grasses are likely to play a central role in the supply of lignocellulose for the cellulosic ethanol industry. Moreover, as these species are evolutionary closely related, advances in each of these crops will expedite improvements in the other crops. This review aims to provide an overview of their potential, prospects and research needs as lignocellulose feedstocks for the commercial production of biofuel. PMID:23653628

  3. Genes related to xylose fermentation and methods of using same for enhanced biofuel production

    DOEpatents

    Wohlbach, Dana J.; Gasch, Audrey P.

    2014-08-05

    The present invention provides isolated gene sequences involved in xylose fermentation and related recombinant yeast which are useful in methods of enhanced biofuel production, particularly ethanol production. Methods of bioengineering recombinant yeast useful for biofuel production are also provided.

  4. Genes related to xylose fermentation and methods of using same for enhanced biofuel production

    SciTech Connect

    Wohlbach, Dana J.; Gasch, Audrey P.

    2015-09-29

    The present invention provides isolated gene sequences involved in xylose fermentation and related recombinant yeast which are useful in methods of enhanced biofuel production, particularly ethanol production. Methods of bioengineering recombinant yeast useful for biofuel production are also provided.

  5. Bioeconomic Sustainability of Cellulosic Biofuel Production on Marginal Lands

    ERIC Educational Resources Information Center

    Gutierrez, Andrew Paul; Ponti, Luigi

    2009-01-01

    The use of marginal land (ML) for lignocellulosic biofuel production is examined for system stability, resilience, and eco-social sustainability. A North American prairie grass system and its industrialization for maximum biomass production using biotechnology and agro-technical inputs is the focus of the analysis. Demographic models of ML biomass…

  6. Utilization of biofuel production residuals for food applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent increase in biofuel production creates a sizable stockpile of its co-product – non-fermentable grain kernel components such as proteins, fibers, and lipids, in the form of Distiller’s Dried Grain with Solubles (DDGS) that has found limited uses in animal feeds. The market demand for DDGS in ...

  7. Managing water resources for biomass production in a biofuel economy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One goal of our national security policy is to become more energy independent using biofuels. The expanded production of agricultural crops for bioenergy production has introduced new challenges for management of water. Water availability has been widely presumed in the discussion of bioenergy crop ...

  8. Bioeconomic Sustainability of Cellulosic Biofuel Production on Marginal Lands

    ERIC Educational Resources Information Center

    Gutierrez, Andrew Paul; Ponti, Luigi

    2009-01-01

    The use of marginal land (ML) for lignocellulosic biofuel production is examined for system stability, resilience, and eco-social sustainability. A North American prairie grass system and its industrialization for maximum biomass production using biotechnology and agro-technical inputs is the focus of the analysis. Demographic models of ML biomass

  9. Soil Quality as an Indicator of Sustainable Biofuel Feedstock Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sustainable production of cellulosic feedstocks for second-generation biofuels must not degrade soil, water, or air resources. Critical functions such as (i) sustaining biological productivity, (ii) regulating and portioning soil water, (iii) storing and cycling nutrients, and (iv) filtering and buf...

  10. Trade-offs between agricultural production and biodiversity for biofuel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Growing energy demands and concerns for climate change have pushed forward the time line for biofuel production. However, the effect of large-scale biofuel production in the U.S. on the agricultural industry, primarily responsible for food production and livestock feed, and biodiversity levels of ma...

  11. Sustainability of biofuels and renewable chemicals production from biomass.

    PubMed

    Kircher, Manfred

    2015-12-01

    In the sectors of biofuel and renewable chemicals the big feedstock demand asks, first, to expand the spectrum of carbon sources beyond primary biomass, second, to establish circular processing chains and, third, to prioritize product sectors exclusively depending on carbon: chemicals and heavy-duty fuels. Large-volume production lines will reduce greenhouse gas (GHG) emission significantly but also low-volume chemicals are indispensable in building 'low-carbon' industries. The foreseeable feedstock change initiates innovation, securing societal wealth in the industrialized world and creating employment in regions producing biomass. When raising the investments in rerouting to sustainable biofuel and chemicals today competitiveness with fossil-based fuel and chemicals is a strong issue. Many countries adopted comprehensive bioeconomy strategies to tackle this challenge. These public actions are mostly biased to biofuel but should give well-balanced attention to renewable chemicals as well. PMID:26256682

  12. Metabolic Engineering of Microalgal Based Biofuel Production: Prospects and Challenges

    PubMed Central

    Banerjee, Chiranjib; Dubey, Kashyap K.; Shukla, Pratyoosh

    2016-01-01

    The current scenario in renewable energy is focused on development of alternate and sustainable energy sources, amongst which microalgae stands as one of the promising feedstock for biofuel production. It is well known that microalgae generate much larger amounts of biofuels in a shorter time than other sources based on plant seeds. However, the greatest challenge in a transition to algae-based biofuel production is the various other complications involved in microalgal cultivation, its harvesting, concentration, drying and lipid extraction. Several green microalgae accumulate lipids, especially triacylglycerols (TAGs), which are main precursors in the production of lipid. The various aspects on metabolic pathway analysis of an oleaginous microalgae i.e., Chlamydomonas reinhardtii have elucidated some novel metabolically important genes and this enhances the lipid production in this microalgae. Adding to it, various other aspects in metabolic engineering using OptFlux and effectual bioprocess design also gives an interactive snapshot of enhancing lipid production which ultimately improvises the oil yield. This article reviews the current status of microalgal based technologies for biofuel production, bioreactor process design, flux analysis and it also provides various strategies to increase lipids accumulation via metabolic engineering. PMID:27065986

  13. Metabolic Engineering of Microalgal Based Biofuel Production: Prospects and Challenges.

    PubMed

    Banerjee, Chiranjib; Dubey, Kashyap K; Shukla, Pratyoosh

    2016-01-01

    The current scenario in renewable energy is focused on development of alternate and sustainable energy sources, amongst which microalgae stands as one of the promising feedstock for biofuel production. It is well known that microalgae generate much larger amounts of biofuels in a shorter time than other sources based on plant seeds. However, the greatest challenge in a transition to algae-based biofuel production is the various other complications involved in microalgal cultivation, its harvesting, concentration, drying and lipid extraction. Several green microalgae accumulate lipids, especially triacylglycerols (TAGs), which are main precursors in the production of lipid. The various aspects on metabolic pathway analysis of an oleaginous microalgae i.e., Chlamydomonas reinhardtii have elucidated some novel metabolically important genes and this enhances the lipid production in this microalgae. Adding to it, various other aspects in metabolic engineering using OptFlux and effectual bioprocess design also gives an interactive snapshot of enhancing lipid production which ultimately improvises the oil yield. This article reviews the current status of microalgal based technologies for biofuel production, bioreactor process design, flux analysis and it also provides various strategies to increase lipids accumulation via metabolic engineering. PMID:27065986

  14. Limits to biofuels

    NASA Astrophysics Data System (ADS)

    Johansson, S.

    2013-06-01

    Biofuel production is dependent upon agriculture and forestry systems, and the expectations of future biofuel potential are high. A study of the global food production and biofuel production from edible crops implies that biofuel produced from edible parts of crops lead to a global deficit of food. This is rather well known, which is why there is a strong urge to develop biofuel systems that make use of residues or products from forest to eliminate competition with food production. However, biofuel from agro-residues still depend upon the crop production system, and there are many parameters to deal with in order to investigate the sustainability of biofuel production. There is a theoretical limit to how much biofuel can be achieved globally from agro-residues and this amounts to approximately one third of todays' use of fossil fuels in the transport sector. In reality this theoretical potential may be eliminated by the energy use in the biomass-conversion technologies and production systems, depending on what type of assessment method is used. By surveying existing studies on biofuel conversion the theoretical limit of biofuels from 2010 years' agricultural production was found to be either non-existent due to energy consumption in the conversion process, or up to 2-6000TWh (biogas from residues and waste and ethanol from woody biomass) in the more optimistic cases.

  15. Optimizing biofuel feedstock production based on impacts on regional water resources and quality

    NASA Astrophysics Data System (ADS)

    Demissie, Y. K.; Yan, E.; Wu, M.

    2012-12-01

    The impact of water pollution on surface water has been of increasing concern as more land and agricultural residues are used for biofuel feedstock production. This study presents the potential impacts of different feedstock production scenarios on regional water resources and quality and further optimize the production using stream discharge and water quality as additional constrains. An integrated watershed hydrology model and optimization algorithm was developed to simulate stream water quality and optimize the change in land use and residue management on the Ohio River Basin, which currently contributes the majority of the flow volume and pollutions of nutrient and sediment to the Mississippi River and Gulf of Mexico. Various plausible future biofuel feedstock production scenarios, including the projection by the DOE Billion Ton Study, were considered to assess the potential impacts on the region and local streams discharges, evapotranspiration, soil moisture content, sediment erosion, nitrogen and phosphorus loadings. Depending on the associated land use and management changes for biofuel, the resulted impacts on the region water resources and stream qualities are found to be mixed with considerable spatial and temporal variations, thus providing an opportunity to further optimize the biomass production by taking into account its potential implication on the basin water resources and quality. An evolution-based optimization technique was applied to optimize the feedstock production by considering their associated impacts on water. The results confirm the capacity to meet both the biofuel and water resources and quality demands.

  16. Biofuels production on abandoned and marginal agriculture lands in the Midwestern United States

    NASA Astrophysics Data System (ADS)

    Campbell, J. E.; Lobell, D. B.; Field, C. B.

    2008-12-01

    The location of biofuels agriculture land is a critical parameter for predicting biomass feedstock yields, land use emissions, and optimal plant varieties. Using abandoned and marginal agriculture lands to grow feedstocks for second-generation biofuels could provide a sustainable alternative to conventional biofuels production. These marginal areas are in a state of flux in the Midwestern U.S. where a 2007 surge in biofuels has contributed to competing land use demands including conventional biofuels crops, food agriculture, and conservation. Here we apply land use and agriculture data to consider the extent and productivity of abandoned and marginal lands in the Midwestern U.S. for production of second-generation biofuels.

  17. Spatially Explicit Life Cycle Assessment of Biofuel Feedstock Production

    EPA Science Inventory

    Biofuels derived from renewable resources have gained increased research and development priority due to increasing energy demand and national security concerns. In the US, the Energy Independence and Security Act (EISA) of 2007 mandated the annual production of 56.8 billion L of...

  18. Will Sulfur Limit Bio-fuel Corn Production?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The short- and long-term effects of striving for higher grain yields and removing crop residues for bio-fuels production on soil-nutrient cycling, physical properties and biological activity must be understood. To provide more quantitative guidelines, soil management studies focusing on tillage, fer...

  19. Production of Liquid Biofuels from Biomass: Emerging Technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This is an overview of the emerging technologies that have been developed recently or are in the process of development for ethanol (biofuel) production from agricultural residues. In this direction numerous advances have been made. Problems associated with inhibitor generation and detoxification,...

  20. Switchgrass: a productive, profitable, and sustainable biofuel feedstock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass is a model biofuel feedstock for the USA. Progress has been made in all areas of switchgrass for bioenergy and a complete field-validated biomass production system has been developed. However, switchgrass for bioenergy has not been adopted on a large scale. This is a classic chicken-and-...

  1. Addressing the challenges for sustainable production of algal biofuels: II. Harvesting and conversion to biofuels.

    PubMed

    Abdelaziz, Ahmed E M; Leite, Gustavo B; Hallenbeck, Patrick C

    2013-01-01

    In order to ensure the sustainability of algal biofuel production, a number of issues need to be addressed. Previously, we reviewed some of the questions in this area involving algal species and the important challenges of nutrient supply and how these might be met. Here, we take up issues involving harvesting and the conversion ofbiomass to biofuels. Advances in both these areas are required if these third-generation fuels are to have a sufficiently high net energy ratio and a sustainable footprint. A variety of harvesting technologies are under investigation and recent studies in this area are presented and discussed. A number of different energy uses are available for algal biomass, each with their own advantages as well as challenges in terms of efficiencies and yields. Recent advances in these areas are presented and some of the especially promising conversion processes are highlighted. PMID:24350436

  2. Hydrocracking of used cooking oil for biofuels production.

    PubMed

    Bezergianni, Stella; Kalogianni, Aggeliki

    2009-09-01

    Hydrocracking of used cooking oil is studied as a potential process for biofuels production. In this work several parameters are considered for evaluating the effectiveness of this technology, including hydrocracking temperature, liquid hourly space velocity (LHSV) and days on stream (DOS). Conversion and total biofuels production is favored by increasing temperature and decreasing LHSV. However moderate reaction temperatures and LHSVs are more attractive for diesel production, whereas higher temperatures and smaller LHSVs are more suitable for gasoline production. Furthermore heteroatom (S, N and O) removal increases as hydrocracking temperature increases, with de-oxygenation being particularly favorable. Saturation, however, is not favored with temperature indicating the necessity of a pre-treatment step prior to hydrocracking to enable saturation of the double bonds and heteroatom removal. Finally the impact of extended operation (catalyst life) on product yields and qualities indicates that all reactions are affected yet at different rates. PMID:19369071

  3. Watershed scale environmental sustainability analysis of biofuel production in changing land use and climate scenarios

    NASA Astrophysics Data System (ADS)

    RAJ, C.; Chaubey, I.; Cherkauer, K. A.; Brouder, S. M.; Volenec, J. J.

    2013-12-01

    One of the grand challenges in meeting the US biofuel goal is producing large quantities of cellulosic biofeedstock materials for the production of biofuels in an environmentally sustainable and economically viable manner. The possible land use and land management practice changes induce concerns over the environmental impacts of these bioenergy crop production scenarios both in terms of water availability and water quality, and these impacts may be exacerbated by climate variability and change. This study aims to evaluate environmental sustainability of various plausible land and crop management scenarios for biofuel production under changing climate scenarios for a Midwest US watershed. The study considers twelve environmental sustainability indicators related hydrology and water quality with thirteen plausible biofuels scenarios in the watershed under nine climate change scenarios. The land use change scenarios for evaluation includes, (1) bioenergy crops in highly erodible soils (3) bioenergy crops in low row crop productive fields (marginal lands); (3) bioenergy crops in pasture and range land use areas and (4) combinations of these scenarios. Future climate data bias corrected and downscaled to daily values from the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset were used in this study. The distributed hydrological model SWAT (Soil and Water Assessment Tool) was used to simulate bioenergy crops growth, hydrology and water quality. The watershed scale sustainability analysis was done in Wildcat Creek basin, which is located in North-Central Indiana, USA.

  4. Synthetic Feedback Loop Model for Increasing Microbial Biofuel Production Using a Biosensor

    PubMed Central

    Harrison, Mary E.; Dunlop, Mary J.

    2012-01-01

    Current biofuel production methods use engineered bacteria to break down cellulose and convert it to biofuel. A major challenge in microbial fuel production is that increasing biofuel yields can be limited by the toxicity of the biofuel to the organism that is producing it. Previous research has demonstrated that efflux pumps are effective at increasing tolerance to various biofuels. However, when overexpressed, efflux pumps burden cells, which hinders growth and slows biofuel production. Therefore, the toxicity of the biofuel must be balanced with the toxicity of pump overexpression. We have developed a mathematical model for cell growth and biofuel production that implements a synthetic feedback loop using a biosensor to control efflux pump expression. In this way, the production rate will be maximal when the concentration of biofuel is low because the cell does not expend energy expressing efflux pumps when they are not needed. Additionally, the microbe is able to adapt to toxic conditions by triggering the expression of efflux pumps, which allow it to continue biofuel production. Sensitivity analysis indicates that the feedback sensor model is insensitive to many system parameters, but a few key parameters can influence growth and production. In comparison to systems that express efflux pumps at a constant level, the feedback sensor increases overall biofuel production by delaying pump expression until it is needed. This result is more pronounced when model parameters are variable because the system can use feedback to adjust to the actual rate of biofuel production. PMID:23112794

  5. Tappable Pine Trees: Commercial Production of Terpene Biofuels in Pine

    SciTech Connect

    2012-01-01

    PETRO Project: The University of Florida is working to increase the amount of turpentine in harvested pine from 4% to 20% of its dry weight. While enhanced feedstocks for biofuels have generally focused on fuel production from leafy plants and grasses, the University of Florida is experimenting with enhancing fuel production in a species of pine that is currently used in the paper pulping industry. Pine trees naturally produce around 3-5% terpene content in the wood—terpenes are the energy-dense fuel molecules that are the predominant components of turpentine. The team aims to increase the terpene storage potential and production capacity while improving the terpene composition to a point at which the trees could be tapped while alive, like sugar maples. Growth and production from these trees will take years, but this pioneering technology could have significant impact in making available an economical and domestic source of aviation and diesel biofuels.

  6. Future Testing Opportunities to Ensure Sustainability of the Biofuels Industry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Energy Independence and Security Act (EISA) of 2007 increased the intensity of biofuel research and development throughout the U.S. For the Soil and Plant Analysis Community, this will undoubtedly create new opportunities to provide analytical services that will help ensure mandates such as the ...

  7. Microalgae as a raw material for biofuels production.

    PubMed

    Gouveia, Luisa; Oliveira, Ana Cristina

    2009-02-01

    Biofuels demand is unquestionable in order to reduce gaseous emissions (fossil CO(2), nitrogen and sulfur oxides) and their purported greenhouse, climatic changes and global warming effects, to face the frequent oil supply crises, as a way to help non-fossil fuel producer countries to reduce energy dependence, contributing to security of supply, promoting environmental sustainability and meeting the EU target of at least of 10% biofuels in the transport sector by 2020. Biodiesel is usually produced from oleaginous crops, such as rapeseed, soybean, sunflower and palm. However, the use of microalgae can be a suitable alternative feedstock for next generation biofuels because certain species contain high amounts of oil, which could be extracted, processed and refined into transportation fuels, using currently available technology; they have fast growth rate, permit the use of non-arable land and non-potable water, use far less water and do not displace food crops cultures; their production is not seasonal and they can be harvested daily. The screening of microalgae (Chlorella vulgaris, Spirulina maxima, Nannochloropsis sp., Neochloris oleabundans, Scenedesmus obliquus and Dunaliella tertiolecta) was done in order to choose the best one(s), in terms of quantity and quality as oil source for biofuel production. Neochloris oleabundans (fresh water microalga) and Nannochloropsis sp. (marine microalga) proved to be suitable as raw materials for biofuel production, due to their high oil content (29.0 and 28.7%, respectively). Both microalgae, when grown under nitrogen shortage, show a great increase (approximately 50%) in oil quantity. If the purpose is to produce biodiesel only from one species, Scenedesmus obliquus presents the most adequate fatty acid profile, namely in terms of linolenic and other polyunsaturated fatty acids. However, the microalgae Neochloris oleabundans, Nannochloropsis sp. and Dunaliella tertiolecta can also be used if associated with other microalgal oils and/or vegetable oils. PMID:18982369

  8. Turning Bacteria into Biofuel: Development of an Integrated Microbial Electrocatalytic (MEC) System for Liquid Biofuel Production from CO2

    SciTech Connect

    2010-08-01

    Electrofuels Project: LBNL is improving the natural ability of a common soil bacteria called Ralstonia eutropha to use hydrogen and carbon dioxide for biofuel production. First, LBNL is genetically modifying the bacteria to produce biofuel at higher concentrations. Then, LBNL is using renewable electricity obtained from solar, wind, or wave power to produce high amounts of hydrogen in the presence of the bacteria—increasing the organism’s access to its energy source and improving the efficiency of the biofuel-creation process. Finally, LBNL is tethering electrocatalysts to the bacteria’s surface which will further accelerate the rate at which the organism creates biofuel. LBNL is also developing a chemical method to transform the biofuel that the bacteria produce into ready-to-use jet fuel.

  9. The role of synthetic biology in the design of microbial cell factories for biofuel production.

    PubMed

    Colin, Vernica Leticia; Rodrguez, Anala; Cristbal, Hctor Antonio

    2011-01-01

    Insecurity in the supply of fossil fuels, volatile fuel prices, and major concerns regarding climate change have sparked renewed interest in the production of fuels from renewable resources. Because of this, the use of biodiesel has grown dramatically during the last few years and is expected to increase even further in the future. Biodiesel production through the use of microbial systems has marked a turning point in the field of biofuels since it is emerging as an attractive alternative to conventional technology. Recent progress in synthetic biology has accelerated the ability to analyze, construct, and/or redesign microbial metabolic pathways with unprecedented precision, in order to permit biofuel production that is amenable to industrial applications. The review presented here focuses specifically on the role of synthetic biology in the design of microbial cell factories for efficient production of biodiesel. PMID:22028591

  10. The Role of Synthetic Biology in the Design of Microbial Cell Factories for Biofuel Production

    PubMed Central

    Colin, Vernica Leticia; Rodrguez, Anala; Cristbal, Hctor Antonio

    2011-01-01

    Insecurity in the supply of fossil fuels, volatile fuel prices, and major concerns regarding climate change have sparked renewed interest in the production of fuels from renewable resources. Because of this, the use of biodiesel has grown dramatically during the last few years and is expected to increase even further in the future. Biodiesel production through the use of microbial systems has marked a turning point in the field of biofuels since it is emerging as an attractive alternative to conventional technology. Recent progress in synthetic biology has accelerated the ability to analyze, construct, and/or redesign microbial metabolic pathways with unprecedented precision, in order to permit biofuel production that is amenable to industrial applications. The review presented here focuses specifically on the role of synthetic biology in the design of microbial cell factories for efficient production of biodiesel. PMID:22028591

  11. Projecting future grassland performance in the Greater Platte River Basin to assess sustainability for potential biofuel feedstock areas

    NASA Astrophysics Data System (ADS)

    Gu, Y.; Wylie, B. K.; Phuyal, K.

    2012-12-01

    In previous studies, we used vegetation condition information from archival records of satellite data (i.e., 10-year time series of Normalized Difference Vegetation Index (NDVI) data), site geophysical and biophysical features (e.g., elevation, slope and aspect, and soils), and weather and climate drivers to build ecosystem performance (EP) models to dynamically monitor EP (DMEP) in the Greater Platte River Basin (GPRB). Ecosystem performance is a surrogate approach for measuring ecosystem productivity. We estimated ecosystem site potentials (i.e., long-term ecosystem productivities), weather-based expected EP (EEP), and rangeland conditions based on these EP models. Validation of the EP results using ground observations (e.g., percentage of bare soil, LANDFIRE maps, stocking rate, and crop yield data) demonstrated the reliability of these EP models. We used this DMEP method to identify grasslands that are potentially suitable for cellulosic biofuel feedstock (e.g., switchgrass) development in the GPRB. The objectives of this study are to (1) project the future grassland EP; (2) assess the changes and trends of the future EP; and (3) examine the future sustainability of the identified biofuel feedstock areas in the GPRB. We used the EP models and future climate projections to estimate future (e.g., 2050 and 2099) climate-based projections of grassland performance in the GPRB. The future climate data were derived from the National Center for Atmospheric Research (NCAR) Community Climate System Model 3.0 (CCSM3) "SRES A1B" (a "middle" emissions path) obtained from the "Bias Corrected and Downscaled WCRP CMIP3 Climate Projections" archive (http://gdo-dcp.ucllnl.org/downscaled_cmip3_projections). Results show that, under climate scenario A1B, the potential biofuel feedstock areas in the more mesic Eastern part of the GPRB will remain productive in the future (the spatially averaged EPs for these areas are 3335 kg ha-1 year-1, 3355 kg ha-1 year-1, and 3341 kg ha-1 year-1 for the site potential, the 2050 EEP, and the 2099 EEP, respectively). Therefore, the identified potential biofuel feedstock areas will continue to be sustainable for future biofuel development. On the other hand, the identified non-biofuel grasslands in the drier Western part of the GPRB would be expected to stay unproductive, with a slight decline in the EP trend in the future (spatially averaged EPs are 1983 kg ha-1 year-1, 1977 kg ha-1 year-1, and 1964 kg ha-1 year-1 for the site potential, the 2050 EEP, and the 2099 EEP, respectively). Thus, these areas will continue to be unsuitable for biofuel feedstock development in the future. The resulting future grassland EEP maps can be used as a reference by land managers to assess the future sustainability and feasibility of the potential biofuel feedstock areas.

  12. Metabolic engineering for isoprenoid-based biofuel production.

    PubMed

    Gupta, P; Phulara, S C

    2015-09-01

    Sustainable economic and industrial growth is the need of the hour and it requires renewable energy resources having better performance and compatibility with existing fuel infrastructure from biological routes. Isoprenoids (C ≥ 5) can be a potential alternative due to their diverse nature and physiochemical properties similar to that of petroleum based fuels. In the past decade, extensive research has been done to utilize metabolic engineering strategies in micro-organisms primarily, (i) to overcome the limitations associated with their natural and non-natural production and (ii) to develop commercially competent microbial strain for isoprenoid-based biofuel production. This review briefly describes the engineered isoprenoid biosynthetic pathways in well-characterized microbial systems for the production of several isoprenoid-based biofuels and fuel precursors. PMID:26095690

  13. Methods and materials for deconstruction of biomass for biofuels production

    SciTech Connect

    Schoeniger, Joseph S; Hadi, Masood Zia

    2015-05-05

    The present invention relates to nucleic acids, peptides, vectors, cells, and plants useful in the production of biofuels. In certain embodiments, the invention relates to nucleic acid sequences and peptides from extremophile organisms, such as SSO1949 and Ce1A, that are useful for hydrolyzing plant cell wall materials. In further embodiments, the invention relates to modified versions of such sequences that have been optimized for production in one or both of monocot and dicot plants. In other embodiments, the invention provides for targeting peptide production or activity to a certain location within the cell or organism, such as the apoplast. In further embodiments, the invention relates to transformed cells or plants. In additional embodiments, the invention relates to methods of producing biofuel utilizing such nucleic acids, peptides, targeting sequences, vectors, cells, and/or plants.

  14. Molecular Breeding of Advanced Microorganisms for Biofuel Production

    PubMed Central

    Sakuragi, Hiroshi; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2011-01-01

    Large amounts of fossil fuels are consumed every day in spite of increasing environmental problems. To preserve the environment and construct a sustainable society, the use of biofuels derived from different kinds of biomass is being practiced worldwide. Although bioethanol has been largely produced, it commonly requires food crops such as corn and sugar cane as substrates. To develop a sustainable energy supply, cellulosic biomass should be used for bioethanol production instead of grain biomass. For this purpose, cell surface engineering technology is a very promising method. In biobutanol and biodiesel production, engineered host fermentation has attracted much attention; however, this method has many limitations such as low productivity and low solvent tolerance of microorganisms. Despite these problems, biofuels such as bioethanol, biobutanol, and biodiesel are potential energy sources that can help establish a sustainable society. PMID:21318120

  15. Molecular breeding of advanced microorganisms for biofuel production.

    PubMed

    Sakuragi, Hiroshi; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2011-01-01

    Large amounts of fossil fuels are consumed every day in spite of increasing environmental problems. To preserve the environment and construct a sustainable society, the use of biofuels derived from different kinds of biomass is being practiced worldwide. Although bioethanol has been largely produced, it commonly requires food crops such as corn and sugar cane as substrates. To develop a sustainable energy supply, cellulosic biomass should be used for bioethanol production instead of grain biomass. For this purpose, cell surface engineering technology is a very promising method. In biobutanol and biodiesel production, engineered host fermentation has attracted much attention; however, this method has many limitations such as low productivity and low solvent tolerance of microorganisms. Despite these problems, biofuels such as bioethanol, biobutanol, and biodiesel are potential energy sources that can help establish a sustainable society. PMID:21318120

  16. Production of biofuels from synthesis gas using microbial catalysts.

    PubMed

    Tirado-Acevedo, Oscar; Chinn, Mari S; Grunden, Amy M

    2010-01-01

    World energy consumption is expected to increase 44% in the next 20 years. Today, the main sources of energy are oil, coal, and natural gas, all fossil fuels. These fuels are unsustainable and contribute to environmental pollution. Biofuels are a promising source of sustainable energy. Feedstocks for biofuels used today such as grain starch are expensive and compete with food markets. Lignocellulosic biomass is abundant and readily available from a variety of sources, for example, energy crops and agricultural/industrial waste. Conversion of these materials to biofuels by microorganisms through direct hydrolysis and fermentation can be challenging. Alternatively, biomass can be converted to synthesis gas through gasification and transformed to fuels using chemical catalysts. Chemical conversion of synthesis gas components can be expensive and highly susceptible to catalyst poisoning, limiting biofuel yields. However, there are microorganisms that can convert the CO, H(2), and CO(2) in synthesis gas to fuels such as ethanol, butanol, and hydrogen. Biomass gasification-biosynthesis processing systems have shown promise as some companies have already been exploiting capable organisms for commercial purposes. The discovery of novel organisms capable of higher product yield, as well as metabolic engineering of existing microbial catalysts, makes this technology a viable option for reducing our dependency on fossil fuels. PMID:20359454

  17. Genetic Engineering of Algae for Enhanced Biofuel Production

    PubMed Central

    Radakovits, Randor; Jinkerson, Robert E.; Darzins, Al; Posewitz, Matthew C.

    2010-01-01

    There are currently intensive global research efforts aimed at increasing and modifying the accumulation of lipids, alcohols, hydrocarbons, polysaccharides, and other energy storage compounds in photosynthetic organisms, yeast, and bacteria through genetic engineering. Many improvements have been realized, including increased lipid and carbohydrate production, improved H2 yields, and the diversion of central metabolic intermediates into fungible biofuels. Photosynthetic microorganisms are attracting considerable interest within these efforts due to their relatively high photosynthetic conversion efficiencies, diverse metabolic capabilities, superior growth rates, and ability to store or secrete energy-rich hydrocarbons. Relative to cyanobacteria, eukaryotic microalgae possess several unique metabolic attributes of relevance to biofuel production, including the accumulation of significant quantities of triacylglycerol; the synthesis of storage starch (amylopectin and amylose), which is similar to that found in higher plants; and the ability to efficiently couple photosynthetic electron transport to H2 production. Although the application of genetic engineering to improve energy production phenotypes in eukaryotic microalgae is in its infancy, significant advances in the development of genetic manipulation tools have recently been achieved with microalgal model systems and are being used to manipulate central carbon metabolism in these organisms. It is likely that many of these advances can be extended to industrially relevant organisms. This review is focused on potential avenues of genetic engineering that may be undertaken in order to improve microalgae as a biofuel platform for the production of biohydrogen, starch-derived alcohols, diesel fuel surrogates, and/or alkanes. PMID:20139239

  18. Cultivation and Characterization of Cynara Cardunculus for Solid Biofuels Production in the Mediterranean Region

    PubMed Central

    Grammelis, Panagiotis; Malliopoulou, Anastasia; Basinas, Panagiotis; Danalatos, Nicholas G.

    2008-01-01

    Technical specifications of solid biofuels are continuously improved towards the development and promotion of their market. Efforts in the Greek market are limited, mainly due to the climate particularity of the region, which hinders the growth of suitable biofuels. Taking also into account the increased oil prices and the high inputs required to grow most annual crops in Greece, cardoon (Cynara cardunculus L.) is now considered the most important and promising sources for solid biofuel production in Greece in the immediate future. The reason is that cardoon is a perennial crop of Mediterranean origin, well adapted to the xerothermic conditions of southern Europe, which can be utilized particularly for solid biofuel production. This is due to its minimum production cost, as this perennial weed may perform high biomass productivity on most soils with modest or without any inputs of irrigation and agrochemicals. Within this framework, the present research work is focused on the planning and analysis of different land use scenarios involving this specific energy crop and the combustion behaviour characterization for the solid products. Such land use scenarios are based on quantitative estimates of the crop'sproduction potential under specific soil-climatic conditions as well as the inputs required for its realization in comparison to existing conventional crops. Concerning its decomposition behaviour, devolatilisation and char combustion tests were performed in a non-isothermal thermogravimetric analyser (TA Q600). A kinetic analysis was applied and accrued results were compared with data already available for other lignocellulosic materials. The thermogravimetric analysis showed that the decomposition process of cardoon follows the degradation of other lignocellulosic fuels, meeting high burnout rates. This research work concludes that Cynara cardunculus, under certain circumstances, can be used as a solid biofuel of acceptable quality. PMID:19325802

  19. Sequencing of Multiple Clostridial Genomes Related to Biomass Conversion and Biofuel Production

    SciTech Connect

    Hemme, Christopher; Mouttaki, Housna; Lee, Yong-Jin; Goodwin, Lynne A.; Lucas, Susan; Copeland, A; Lapidus, Alla L.; Glavina Del Rio, Tijana; Tice, Hope; Saunders, Elizabeth H; Detter, J. Chris; Han, Cliff; Pitluck, Sam; Land, Miriam L; Hauser, Loren John; Kyrpides, Nikos C; Mikhailova, Natalia; He, Zhili; Wu, Liyou; Van Nostrand, Joy; Henrissat, Bernard; HE, Qiang; Lawson, Paul A.; Tanner, Ralph S.; Lynd, Lee R; Wiegel, Juergen; Fields, Dr. Matthew Wayne; Arkin, Adam; Schadt, Christopher Warren; Stevenson, Bradley S.; McInerney, Michael J.; Yang, Yunfeng; Dong, Hailiang; Xing, Defeng; Ren, Nanqi; Wang, Aijie; Ding, Shi-You; Himmel, Michael E; Taghavi, Safiyh; Rubin, Edward M.; Zhou, Jizhong

    2010-01-01

    Modern methods to develop microbe-based biomass conversion processes require a system-level understanding of the microbes involved. Clostridium species have long been recognized as ideal candidates for processes involving biomass conversion and production of various biofuels and other industrial products. To expand the knowledge base for clostridial species relevant to current biofuel production efforts, we have sequenced the genomes of 20 species spanning multiple genera. The majority of species sequenced fall within the class III cellulosome-encoding Clostridium and the class V saccharolytic Thermoanaerobacteraceae. Species were chosen based on representation in the experimental literature as model organisms, ability to degrade cellulosic biomass either by free enzymes or by cellulosomes, ability to rapidly ferment hexose and pentose sugars to ethanol, and ability to ferment synthesis gas to ethanol. The sequenced strains significantly increase the number of noncommensal/nonpathogenic clostridial species and provide a key foundation for future studies of biomass conversion, cellulosome composition, and clostridial systems biology.

  20. Fatty acid alkyl esters: perspectives for production of alternative biofuels.

    PubMed

    Röttig, Annika; Wenning, Leonie; Bröker, Daniel; Steinbüchel, Alexander

    2010-02-01

    The global economy heads for a severe energy crisis: whereas the energy demand is going to rise, easily accessible sources of crude oil are expected to be depleted in only 10-20 years. Since a serious decline of oil supply and an associated collapse of the economy might be reality very soon, alternative energies and also biofuels that replace fossil fuels must be established. In addition, these alternatives should not further impair the environment and climate. About 90% of the biofuel market is currently captured by bioethanol and biodiesel. Biodiesel is composed of fatty acid alkyl esters (FAAE) and can be synthesized by chemical, enzymatic, or in vivo catalysis mainly from renewable resources. Biodiesel is already established as it is compatible with the existing fuel infrastructure, non-toxic, and has superior combustion characteristics than fossil diesel; and in 2008, the global production was 12.2 million tons. The biotechnological production of FAAE from low cost and abundant feedstocks like biomass will enable an appreciable substitution of petroleum diesel. To overcome high costs for immobilized enzymes, the in vivo synthesis of FAAE using bacteria represents a promising approach. This article points to the potential of different FAAE as alternative biofuels, e.g., by comparing their fuel properties. In addition to conventional production processes, this review presents natural and genetically engineered biological systems capable of in vivo FAAE synthesis. PMID:20033403

  1. BIOFUEL AND BIOENERGY PRODUCTION FROM SUGAR BEETS

    EPA Science Inventory

    A design spreadsheet model for sizing and analyzing the integrated ethanol and biogas production system, a prototype of the ethanol and biogas production system in the laboratory that has been tested and documented with performance data, and a design and operating manual for t...

  2. Feeding biofuels co-products to pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Distillers dried grains with solubles (DDGS) and other co-products from the fuel ethanol industry may be included in diets fed to pigs in all phases of production. The concentration of digestible energy (DE) and metabolizable energy (ME) in DDGS and corn germ is similar to corn, but high protein dis...

  3. Increasing Feedstock Production for Biofuels: Economic Drivers, Environmental Implications, and the Role of Research

    SciTech Connect

    none,

    2009-10-27

    The Biomass Research and Development Board (Board) commissioned an economic analysis of feedstocks to produce biofuels. The Board seeks to inform investments in research and development needed to expand biofuel production. This analysis focuses on feedstocks; other interagency teams have projects underway for other parts of the biofuel sector (e.g., logistics). The analysis encompasses feedstocks for both conventional and advanced biofuels from agriculture and forestry sources.

  4. Microalgal Triacylglycerols as Feedstocks for Biofuel Production: Perspectives and Advances

    SciTech Connect

    Hu, Q.; Sommerfeld, M.; Jarvis, E.; Ghirardi, M.; Posewitz, M; Seibert, M.; Darzins, A.

    2008-01-01

    Microalgae represent an exceptionally diverse but highly specialized group of micro-organisms adapted to various ecological habitats. Many microalgae have the ability to produce substantial amounts (e.g. 20-50% dry cell weight) of triacylglycerols (TAG) as a storage lipid under photo-oxidative stress or other adverse environmental conditions. Fatty acids, the building blocks for TAGs and all other cellular lipids, are synthesized in the chloroplast using a single set of enzymes, of which acetyl CoA carboxylase (ACCase) is key in regulating fatty acid synthesis rates. However, the expression of genes involved in fatty acid synthesis is poorly understood in microalgae. Synthesis and sequestration of TAG into cytosolic lipid bodies appear to be a protective mechanism by which algal cells cope with stress conditions, but little is known about regulation of TAG formation at the molecular and cellular level. While the concept of using microalgae as an alternative and renewable source of lipid-rich biomass feedstock for biofuels has been explored over the past few decades, a scalable, commercially viable system has yet to emerge. Today, the production of algal oil is primarily confined to high-value specialty oils with nutritional value, rather than commodity oils for biofuel. This review provides a brief summary of the current knowledge on oleaginous algae and their fatty acid and TAG biosynthesis, algal model systems and genomic approaches to a better understanding of TAG production, and a historical perspective and path forward for microalgae-based biofuel research and commercialization.

  5. Alternatives to Trichoderma reesei in biofuel production.

    PubMed

    Gusakov, Alexander V

    2011-09-01

    Mutant strains of Trichoderma reesei are considered indisputable champions in cellulase production among biomass-degrading fungi. So, it is not surprising that most R&D projects on bioethanol production from lignocellulosics have been based on using T. reesei cellulases. The present review focuses on whether any serious alternatives to T. reesei enzymes in cellulose hydrolysis exist. Although not widely accepted, more and more data have been accumulated that demonstrate that fungi belonging to the genera Penicillium, Acremonium and Chrysosporium might represent such alternatives because they are competitive to T. reesei on some important parameters, such as protein production level, cellulase hydrolytic performance per unit of activity or milligram of protein. PMID:21612834

  6. Integrated Biorefineries with Engineered Microbes and High-value Co-products for Profitable Biofuels Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Corn-based fuel ethanol production processes provide several advantages which could be synergistically applied to overcome limitations of biofuel processes based on lignocellulose. These include resources such as equipment, manpower, nutrients, water, and heat. The fact that several demonstration-...

  7. Switchgrass (Panicum virgatum) for biofuel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass (Panicum virgatum) is a native warm-season grass that is a leading biomass crop in the US. More than 70-years of experience with switchgrass as a hay and forage crop suggests switchgrass will be productive and sustainable on rain-fed marginal land east of the 100th Meridian. Long-term p...

  8. National Microalgae Biofuel Production Potential and Resource Demand

    SciTech Connect

    Wigmosta, Mark S.; Coleman, Andre M.; Skaggs, Richard; Huesemann, Michael H.; Lane, Leonard J.

    2011-04-14

    Microalgae continue to receive global attention as a potential sustainable "energy crop" for biofuel production. An important step to realizing the potential of algae is quantifying the demands commercial-scale algal biofuel production will place on water and land resources. We present a high-resolution national resource and oil production assessment that brings to bear fundamental research questions of where open pond microalgae production can occur, how much land and water resource is required, and how much energy is produced. Our study suggests under current technology microalgae have the potential to generate 220 billion liters/year of oil, equivalent to 48% of current U.S. petroleum imports for transportation fuels. However, this level of production would require 5.5% of the land area in the conterminous U.S., and nearly three times the volume of water currently used for irrigated agriculture, averaging 1,421 L water per L of oil. Optimizing the selection of locations for microalgae production based on water use efficiency can greatly reduce total water demand. For example, focusing on locations along the Gulf Coast, Southeastern Seaboard, and areas adjacent to the Great Lakes, shows a 75% reduction in water demand to 350 L per L of oil produced with a 67% reduction in land use. These optimized locations have the potential to generate an oil volume equivalent to 17% of imports for transportation fuels, equal to the Energy Independence and Security Act year 2022 "advanced biofuels" production target, and utilizing some 25% of the current irrigation consumptive water demand for the U. S. These results suggest that, with proper planning, adequate land and water are available to meet a significant portion of the U.S. renewable fuel goals.

  9. National microalgae biofuel production potential and resource demand

    NASA Astrophysics Data System (ADS)

    Wigmosta, Mark S.; Coleman, André M.; Skaggs, Richard J.; Huesemann, Michael H.; Lane, Leonard J.

    2011-03-01

    Microalgae are receiving increased global attention as a potential sustainable "energy crop" for biofuel production. An important step to realizing the potential of algae is quantifying the demands commercial-scale algal biofuel production will place on water and land resources. We present a high-resolution spatiotemporal assessment that brings to bear fundamental questions of where production can occur, how many land and water resources are required, and how much energy is produced. Our study suggests that under current technology, microalgae have the potential to generate 220 × 109 L yr-1 of oil, equivalent to 48% of current U.S. petroleum imports for transportation. However, this level of production requires 5.5% of the land area in the conterminous United States and nearly three times the water currently used for irrigated agriculture, averaging 1421 L water per liter of oil. Optimizing the locations for microalgae production on the basis of water use efficiency can greatly reduce total water demand. For example, focusing on locations along the Gulf Coast, southeastern seaboard, and Great Lakes shows a 75% reduction in consumptive freshwater use to 350 L per liter of oil produced with a 67% reduction in land use. These optimized locations have the potential to generate an oil volume equivalent to 17% of imports for transportation fuels, equal to the Energy Independence and Security Act year 2022 "advanced biofuels" production target and utilizing some 25% of the current irrigation demand. With proper planning, adequate land and water are available to meet a significant portion of the U.S. renewable fuel goals.

  10. PETRO: Higher Productivity Crops for Biofuels

    SciTech Connect

    2012-01-01

    PETRO Project: The 10 projects that comprise ARPA-E’s PETRO Project, short for “Plants Engineered to Replace Oil,” aim to develop non-food crops that directly produce transportation fuel. These crops can help supply the transportation sector with agriculturally derived fuels that are cost-competitive with petroleum and do not affect U.S. food supply. PETRO aims to redirect the processes for energy and carbon dioxide (CO2) capture in plants toward fuel production. This would create dedicated energy crops that serve as a domestic alternative to petroleum-based fuels and deliver more energy per acre with less processing prior to the pump.

  11. Biofuel production system with operation flexibility: Evaluation of economic and environmental performance under external disturbance

    NASA Astrophysics Data System (ADS)

    Kou, Nannan

    Biomass derived liquid hydrocarbon fuel (biofuel) has been accepted as an effective way to mitigate the reliance on petroleum and reduce the greenhouse gas emissions. An increasing demand for second generation biofuels, produced from ligno-cellulosic feedstock and compatible with current infrastructure and vehicle technologies, addresses two major challenges faced by the current US transportation sector: energy security and global warming. However, biofuel production is subject to internal disturbances (feedstock supply and commodity market) and external factors (energy market). The biofuel industry has also heavily relied on government subsidy during the early development stages. In this dissertation, I investigate how to improve the economic and environmental performance of biorefineries (and biofuel plant), as well as enhance its survivability under the external disturbances. Three types of disturbance are considered: (1) energy market fluctuation, (2) subsidy policy uncertainty, and (3) extreme weather conditions. All three factors are basically volatile, dynamic, and even unpredictable, which makes them difficult to model and have been largely ignored to date. Instead, biofuel industry and biofuel research are intensively focused on improving feedstock conversion efficiency and capital cost efficiency while assuming these advancements alone will successfully generate higher profit and thus foster the biofuel industry. The collapse of the largest corn ethanol biofuel company, Verasun Energy, in 2008 calls into question this efficiency-driven approach. A detailed analysis has revealed that although the corn ethanol plants operated by Verasun adopted the more efficient (i.e. higher ethanol yield per bushel of corn and lower capital cost) dry-mill technology, they could not maintain a fair profit margin under fluctuating market condition which made ethanol production unprofitable. This is because dry-mill plant converts a single type of biomass feedstock (corn grain) into a single primary product (ethanol). The traditional lower efficient (i.e. lower ethanol yield per bushel of corn and higher capital cost) wet-mill plant has a more diverse and adjustable product portfolio i.e. corn syrup, starch, and ethanol. The fact that only the dry-mill corn ethanol plants have bankrupted while the wet-mill corn ethanol plants have survived the late 2000s economy recession suggests that the higher conversion efficiency achieved by the dry-mill production mode has jeopardized operational flexibility, a design operational feature I agree that is indispensable for the biofuel plant's long term profit and viability. Based on the analysis of corn ethanol production, operational flexibility has been proposed as a key strategy for the next generation biofuel plants to improve its lifetime economic performance, as well as to enhance its survivability under external disturbances. This strategy requires the biofuel plant to adopt a flexible feedstock management, making it possible to utilize alternative types of biomass feedstock when the primary feedstock supply is disturbed. Biofuel plants also need to produce a wider range of final products that could meet the preference variation that either comes from the energy market or from the subsidy policy. Aspen Plus model based numerical simulations have been carried out for a thermochemical ethanol plant and a Fischer Tropsch plant (both are assumed to be located in southwest Indiana) to test this strategy under the external disturbances of extreme weather impact, different energy price projections and various subsidy policy combinations. For the thermochemical ethanol plant, effects of extreme weather conditions are mainly evaluated. It has been shown that this strategy could effectively increase the net present value of the biofuel plant and significantly decrease the GHG emission comparing with the traditional single-feedstock strategy, when the extreme weather conditions are considered. It has also been demonstrated that this strategy could significantly decrease the possibility for the biofuel plant to bankrupt. For the Fischer Tropsch diesel plant, all the three external disturbances have been examined. It has been learned that operational flexibility through full capacity power co-generation, flexible feedstock management and hydrogen production by natural gas autothermal reforming could maximize the net present value under the influence of the external disturbances. Thus it is suggested that the future biofuel plant should adopt operational flexibility to increase the lifetime economic performance and to enhance the survivability under the influence of external disturbance.

  12. Measured and modelled carbon and water fluxes in hybrid willows grown for biofuel production

    NASA Astrophysics Data System (ADS)

    Wertin, T. M.; LeBauer, D.; Volk, T.; Long, S.; Leakey, A. D.

    2014-12-01

    Biofuels have the potential to meet future energy needs. Worldwide, up to 75% of biofuels produced are derived from woody sources. Coppiced hybrid willow is among the most promising woody biofuel sources due to its ability to rapidly regenerate after cutting, high biomass yields, low nutrient requirements and ability to be grown on marginal land, abandoned land and land easily erodible under annual cultivation. However, models used to assess the potential viability and sustainability of commercial biomass production by willow in the northeastern, northern and northwestern USA remain unsophisticated and lack key parameterization data. Most significantly, models do not explicitly represent the coppiced growth form. This study tests the ability of a canopy model to predict carbon and water fluxes in two highly productive, but structurally distinct hybrid willows (Salix miyabeana and Salix purpurea) grown in central NY. S. miyaneana has only a few, large diameter stems per stool prior to harvest, while S. purpurea maintains numerous, small diameter stems until harvest. Canopy structure also varies substantially within a growing season. For example, in S. miyabeana stem number decreased by 40% while total basal area increased by 50% within year 2 of the third coppice cycle. Model predictions of water use are compared with stand transpiration measured by sap flow. Model predictions of biomass production are compared to destructive harvest data. Sensitivity of predicted fluxes to variation between genotypes in key physiological parameters is also tested.

  13. A model for improving microbial biofuel production using a synthetic feedback loop

    SciTech Connect

    Dunlop, Mary; Keasling, Jay; Mukhopadhyay, Aindrila

    2011-07-14

    Cells use feedback to implement a diverse range of regulatory functions. Building synthetic feedback control systems may yield insight into the roles that feedback can play in regulation since it can be introduced independently of native regulation, and alternative control architectures can be compared. We propose a model for microbial biofuel production where a synthetic control system is used to increase cell viability and biofuel yields. Although microbes can be engineered to produce biofuels, the fuels are often toxic to cell growth, creating a negative feedback loop that limits biofuel production. These toxic effects may be mitigated by expressing efflux pumps that export biofuel from the cell. We developed a model for cell growth and biofuel production and used it to compare several genetic control strategies for their ability to improve biofuel yields. We show that controlling efflux pump expression directly with a biofuel-responsive promoter is a straight forward way of improving biofuel production. In addition, a feed forward loop controller is shown to be versatile at dealing with uncertainty in biofuel production rates.

  14. An integrative modeling framework to evaluate the productivity and sustainability of biofuel crop production systems

    SciTech Connect

    Zhang, X; Izaurralde, R. C.; Manowitz, D.; West, T. O.; Thomson, A. M.; Post, Wilfred M; Bandaru, Vara Prasad; Nichols, Jeff; Williams, J.

    2010-10-01

    The potential expansion of biofuel production raises food, energy, and environmental challenges that require careful assessment of the impact of biofuel production on greenhouse gas (GHG) emissions, soil erosion, nutrient loading, and water quality. In this study, we describe a spatially explicit integrative modeling framework (SEIMF) to understand and quantify the environmental impacts of different biomass cropping systems. This SEIMF consists of three major components: (1) a geographic information system (GIS)-based data analysis system to define spatial modeling units with resolution of 56 m to address spatial variability, (2) the biophysical and biogeochemical model Environmental Policy Integrated Climate (EPIC) applied in a spatially-explicit way to predict biomass yield, GHG emissions, and other environmental impacts of different biofuel crops production systems, and (3) an evolutionary multiobjective optimization algorithm for exploring the trade-offs between biofuel energy production and unintended ecosystem-service responses. Simple examples illustrate the major functions of the SEIMF when applied to a nine-county Regional Intensive Modeling Area (RIMA) in SW Michigan to (1) simulate biofuel crop production, (2) compare impacts of management practices and local ecosystem settings, and (3) optimize the spatial configuration of different biofuel production systems by balancing energy production and other ecosystem-service variables. Potential applications of the SEIMF to support life cycle analysis and provide information on biodiversity evaluation and marginal-land identification are also discussed. The SEIMF developed in this study is expected to provide a useful tool for scientists and decision makers to understand sustainability issues associated with the production of biofuels at local, regional, and national scales.

  15. An Integrative Modeling Framework to Evaluate the Productivity and Sustainability of Biofuel Crop Production Systems

    SciTech Connect

    Zhang, Xuesong; Izaurralde, Roberto C.; Manowitz, David H.; West, T. O.; Post, W. M.; Thomson, Allison M.; Bandaru, V. P.; Nichols, J.; Williams, J.R.

    2010-09-08

    The potential expansion of biofuel production raises food, energy, and environmental challenges that require careful assessment of the impact of biofuel production on greenhouse gas (GHG) emissions, soil erosion, nutrient loading, and water quality. In this study, we describe a spatially-explicit integrative modeling framework (SEIMF) to understand and quantify the environmental impacts of different biomass cropping systems. This SEIMF consists of three major components: 1) a geographic information system (GIS)-based data analysis system to define spatial modeling units with resolution of 56 m to address spatial variability, 2) the biophysical and biogeochemical model EPIC (Environmental Policy Integrated Climate) applied in a spatially-explicit way to predict biomass yield, GHG emissions, and other environmental impacts of different biofuel crops production systems, and 3) an evolutionary multi-objective optimization algorithm for exploring the trade-offs between biofuel energy production and unintended ecosystem-service responses. Simple examples illustrate the major functions of the SEIMF when applied to a 9-county Regional Intensive Modeling Area (RIMA) in SW Michigan to 1) simulate biofuel crop production, 2) compare impacts of management practices and local ecosystem settings, and 3) optimize the spatial configuration of different biofuel production systems by balancing energy production and other ecosystem-service variables. Potential applications of the SEIMF to support life cycle analysis and provide information on biodiversity evaluation and marginal-land identification are also discussed. The SEIMF developed in this study is expected to provide a useful tool for scientists and decision makers to understand sustainability issues associated with the production of biofuels at local, regional, and national scales.

  16. Soil carbon sequestration or biofuel production: new land-use opportunities for mitigating climate over abandoned Soviet farmlands.

    PubMed

    Vuichard, Nicolas; Ciais, Philippe; Wolf, Adam

    2009-11-15

    Although the CO(2) mitigation potential of biofuels has been studied by extrapolation of small-scale studies, few estimates exist of the net regional-scale carbon balance implications of biofuel cultivations programs, either growing conventional biofuel crops or applying new advanced technologies. Here we used a spatially distributed process-driven model over the 20 Mha of recently abandoned agricultural lands of the Former Soviet Union to quantify the GHG mitigation by biofuel production from Low Input/High Diversity (LIHD) grass-legume prairies and to compare this GHG mitigation with the one of soil C sequestration as it currently occurs. LIHD has recently received a lot of attention as an emerging opportunity to produce biofuels over marginal lands leading to a good energy efficiency with minimal adverse consequences on food security and ecosystem services. We found that, depending on the time horizon over which one seeks to maximize the GHG benefit, the optimal time for implementing biofuel production shifts from "never" (short-term horizon) to "as soon as possible" (longer-term horizon). These results highlight the importance of reaching agreement a priori on the target time interval during which biofuels are expected to play a role within the global energy system, to avoid deploying biofuel technology over a time interval for which it has a detrimental impact on the GHG mitigation objective. The window of opportunity for growing LIHD also stresses the need to reduce uncertainties in soil C inputs, turnover, and soil organic matter stability under current and future climate and management practices. PMID:20028070

  17. The impact of extreme drought on the biofuel feedstock production

    NASA Astrophysics Data System (ADS)

    hussain, M.; Zeri, M.; Bernacchi, C.

    2013-12-01

    Miscanthus (Miscanthus x giganteus) and Switchgrass (Panicum virgatum) have been identified as the primary targets for second-generation cellulosic biofuel crops. Prairie managed for biomass is also considered as one of the alternative to conventional biofuel and promised to provide ecosystem services, including carbon sequestration. These perennial grasses possess a number of traits that make them desirable biofuel crops and can be cultivated on marginal lands or interspersed with maize and soybean in the Corn Belt region. The U.S. Corn Belt region is the world's most productive and expansive maize-growing region, approximately 20% of the world's harvested corn hectares are found in 12 Corn Belt states. The introduction of a second generation cellulosic biofuels for biomass production in a landscape dominated by a grain crop (maize) has potential implications on the carbon and water cycles of the region. This issue is further intensified by the uncertainty in the response of the vegetation to the climate change induced drought periods, as was seen during the extreme droughts of 2011 and 2012 in the Midwest. The 2011 and 2012 growing seasons were considered driest since the 1932 dust bowl period; temperatures exceeded 3.0 °C above the 50- year mean and precipitation deficit reached 50 %. The major objective of this study was to evaluate the drought responses (2011 and 2012) of corn and perennial species at large scale, and to determine the seasonability of carbon and water fluxes in the response of controlling factors. We measured net CO2 ecosystem exchange (NEE) and water fluxes of maize-maize-soybean, and perennial species such as miscanthus, switchgrass and mixture of prairie grasses, using eddy covariance in the University of Illinois energy farm at Urbana, IL. The data presented here were for 5 years (2008- 2012). In the first two years, higher NEE in maize led to large CO2 sequestration. NEE however, decreased in dry years, particularly in 2012. On the other hand, miscanthus, switchgrass, and to a lesser extent, prairie showed higher NEE and gross primary production (GPP) - a partitioned NEE component - than maize during 2012. Although miscanthus uses more water relative to maize (consumed 30 % more water), Net Ecosystem Carbon Balance (NECB) results show that it provides the greatest net benefits of sequestering atmospheric CO2 during drought. Our findings highlight the important role of perennial species in sustaining productivity and sequestering CO2 during drought, as compared to maize. We conclude that changing land use from row crops to perennial species will result in more sequestered carbon, even with drought stress, and will be more resilient to prolonged dry periods.

  18. A new diet for yeast to improve biofuel production

    PubMed Central

    Galazka, Jonathan M

    2011-01-01

    In 2010, our group announced the discovery of two cellodextrin transporter families from the cellulolytic fungus Neurospora crassa. Furthermore, we demonstrated the utility of these transporters in the production of lignocellulosic biofuels. This discovery was made possible by a decision to systematically study cell wall degradation by N. crassa. The identified transport pathway has opened up a new way of thinking about microbial fermentation of hexoses as well as pentoses derived from plant cell walls. Integrating this pathway with the endogenous metabolism and signaling networks of S. cerevisiae is now a major goal of our group. PMID:21637011

  19. Recent trends in nanomaterials immobilised enzymes for biofuel production.

    PubMed

    Verma, Madan L; Puri, Munish; Barrow, Colin J

    2016-02-01

    Application of nanomaterials as novel supporting materials for enzyme immobilisation has generated incredible interest in the biotechnology community. These robust nanostructured forms, such as nanoparticles, nanofibres, nanotubes, nanoporous, nanosheets, and nanocomposites, possess a high surface area to volume ratios that can cause a high enzyme loading and facilitate reaction kinetics, thus improving biocatalytic efficiency for industrial applications. In this article, we discuss research opportunities of nanoscale materials in enzyme biotechnology and highlight recent developments in biofuel production using advanced material supports for enzyme immobilisation and stabilisation. Synthesis and functionalisation of nanomaterial forms using different methods are highlighted. Various simple and effective strategies designed to result in a stable, as well as functional protein-nanomaterial conjugates are also discussed. Analytical techniques confirming enzyme loading on nanomaterials and assessing post-immobilisation changes are discussed. The current status of versatile nanomaterial support for biofuel production employing cellulases and lipases is described in details. This report concludes with a discussion on the likely outcome that nanomaterials will become an integral part of sustainable bioenergy production. PMID:25017196

  20. Fields of dreams: Agriculture, economy and nature in Midwest United States biofuel production

    NASA Astrophysics Data System (ADS)

    Gillon, Sean Thomas

    This work explores the social and ecological dimensions of recent biofuel production increases in the United States (US), focusing on the case of Iowa. Biofuels are proposed to mitigate the greenhouse gas emissions that cause climate change, improve US energy security, and support rural economies. Little research has examined how increased US Midwestern biofuels production will change social and ecological outcomes at farm and regional levels or interact with broader governance processes at the nexus of agriculture, energy and environment. These broad questions guide my research: (1) How does biofuel production reconfigure agricultural practice and landscapes in Iowa? (2) What are the costs, benefits and risks of increased biofuels production as seen by farmers and rural residents, and how do these factors influence farmer decisions about agriculture and conservation practice? (3) How and with what effects are biofuels initiatives constituted as a form of environmental governance through scientific knowledge and practice and political economic dynamics? To address these questions, this research integrates both qualitative and quantitative methods, drawing on a political ecological approach complemented by agroecological analysis and theoretical insights from geographical analyses of nature-society relations. Quantitative analysis focuses on changing land use patterns in agriculture and conservation practice in Iowa. Qualitative methods include extensive interviews, participant observation, and policy and document analyses. Fieldwork focused on Northeastern Iowa to understand regional changes in agricultural and conservation practice, the renegotiated position of farmers in agriculture and biofuel production, and biofuel industry development. I find that biofuel production presents significant social and ecological challenges for rural places of production. Longstanding, unequal political economic relations in industrialized agriculture limit rural economic benefits. I describe how biofuel governance focuses on scientific practices that legitimize biofuel production for their capacity to marginally reduce greenhouse gas emissions, despite biofuels' agroecological consequences outside this regulatory purview. These consequences include pressure on conservation and agrienvironmental practice, which could be better supported through existing, highly effective, place-based, democratic institutions dedicated to stewarding the resources upon which agricultural livelihoods depend.

  1. Biofuel production improvement with genome-scale models: The role of cell composition.

    PubMed

    Senger, Ryan S

    2010-07-01

    Genome-scale models have developed into a vital tool for rational metabolic engineering. These models balance cofactors and energetic requirements and determine biosynthetic precursor availability in response to environmental and genetic perturbations. In particular, allocation of additional reducing power is an important strategy for engineering potential biofuel production from microbes. Many potential biofuel solvents induce biomolecular changes on the host organism that are not yet captured by genome-scale models. Here, methods of construction for several biomass constituting equations are reviewed along with potential changes to cellular composition with potential biofuels exposure. The biomass constituting equations of potential host organisms with existing genome-scale models are compared side-by-side to explore their evolution over the years and to explore differences that arise when these equations are compiled by different research groups. Genome-scale model simulation results attempt to address and provide guidance for further research into: (i) whether inconsistencies in the biomass constituting equations are relevant to predictions of solvent production, (ii) what level of detail is necessary to accurately describe cellular composition, and (iii) future developments that may enable more accurate characterizations of biomolecular composition. PMID:20540108

  2. New biofuel alternatives: integrating waste management and single cell oil production.

    PubMed

    Martínez, Elia Judith; Raghavan, Vijaya; González-Andrés, Fernando; Gómez, Xiomar

    2015-01-01

    Concerns about greenhouse gas emissions have increased research efforts into alternatives in bio-based processes. With regard to transport fuel, bioethanol and biodiesel are still the main biofuels used. It is expected that future production of these biofuels will be based on processes using either non-food competing biomasses, or characterised by low CO₂ emissions. Many microorganisms, such as microalgae, yeast, bacteria and fungi, have the ability to accumulate oils under special culture conditions. Microbial oils might become one of the potential feed-stocks for biodiesel production in the near future. The use of these oils is currently under extensive research in order to reduce production costs associated with the fermentation process, which is a crucial factor to increase economic feasibility. An important way to reduce processing costs is the use of wastes as carbon sources. The aim of the present review is to describe the main aspects related to the use of different oleaginous microorganisms for lipid production and their performance when using bio-wastes. The possibilities for combining hydrogen (H₂) and lipid production are also explored in an attempt for improving the economic feasibility of the process. PMID:25918941

  3. New Biofuel Alternatives: Integrating Waste Management and Single Cell Oil Production

    PubMed Central

    Martínez, Elia Judith; Raghavan, Vijaya; González-Andrés, Fernando; Gómez, Xiomar

    2015-01-01

    Concerns about greenhouse gas emissions have increased research efforts into alternatives in bio-based processes. With regard to transport fuel, bioethanol and biodiesel are still the main biofuels used. It is expected that future production of these biofuels will be based on processes using either non-food competing biomasses, or characterised by low CO2 emissions. Many microorganisms, such as microalgae, yeast, bacteria and fungi, have the ability to accumulate oils under special culture conditions. Microbial oils might become one of the potential feed-stocks for biodiesel production in the near future. The use of these oils is currently under extensive research in order to reduce production costs associated with the fermentation process, which is a crucial factor to increase economic feasibility. An important way to reduce processing costs is the use of wastes as carbon sources. The aim of the present review is to describe the main aspects related to the use of different oleaginous microorganisms for lipid production and their performance when using bio-wastes. The possibilities for combining hydrogen (H2) and lipid production are also explored in an attempt for improving the economic feasibility of the process. PMID:25918941

  4. Biofuel Production Initiative at Claflin University Final Report

    SciTech Connect

    Chowdhury, Kamal

    2011-07-20

    For US transportation fuel independence or reduced dependence on foreign oil, the Federal Government has mandated that the country produce 36 billion gallons (bg) of renewable transportation fuel per year for its transportation fuel supply by 2022. This can be achieved only if development of efficient technology for second generation biofuel from ligno-cellulosic sources is feasible. To be successful in this area, development of a widely available, renewable, cost-effective ligno-cellulosic biomass feedstock that can be easily and efficiently converted biochemically by bacteria or other fast-growing organisms is required. Moreover, if the biofuel type is butanol, then the existing infrastructure to deliver fuel to the customer can be used without additional costs and retrofits. The Claflin Biofuel Initiative project is focused on helping the US meet the above-mentioned targets. With support from this grant, Claflin University (CU) scientists have created over 50 new strains of microorganisms that are producing butanol from complex carbohydrates and cellulosic compounds. Laboratory analysis shows that a number of these strains are producing higher percentages of butanol than other methods currently in use. All of these recombinant bacterial strains are producing relatively high concentrations of acetone and numerous other byproducts as well. Therefore, we are carrying out intense mutations in the selected strains to reduce undesirable byproducts and increase the desired butanol production to further maximize the yield of butanol. We are testing the proof of concept of producing pre-industrial large scale biobutanol production by utilizing modifications of currently commercially available fermentation technology and instrumentation. We have already developed an initial process flow diagram (PFD) and selected a site for a biobutanol pilot scale facility in Orangeburg, SC. With the recent success in engineering new strains of various biofuel producing bacteria at CU, it will soon be possible to provide other technical information for the development of process flow diagrams (PFD’s) and piping and instrumentation diagrams (P&ID’s). This information can be used for the equipment layout and general arrangement drawings for the proposed process and eventual plant. An efficient bio-butanol pilot plant to convert ligno-cellulosic biomass feedstock from bagasse and wood chips will create significant number of green jobs for the Orangeburg, SC community that will be environmentally-friendly and generate much-needed income for farmers in the area.

  5. Biofuels Feedstock Development Program: 1995 activities and future directions

    SciTech Connect

    Ferrell, J.E.; Wright, L.L.; Tuskan, G.A.

    1995-12-31

    The Department of Energy`s (DOE`s) Biofuels Feedstock Development Program (BFDP) has led the nation in developing short-rotation woody crops (SRWC) and herbaceous energy crops (HEC) as feedstocks for renewable energy. Since 1978, approximately $60 million has been invested in research projects involving more than 100 federal, university, and private research institutions. The research has been highly leveraged with cost-sharing from USDA Forest Service, private industry, and state agencies. The performance of 154 woody species and 35 herbaceous species has been examined in field trials across the U.S. Results of this effort include the prescription of silvi-cultural systems for hybrid poplars and hybrid willows and agricultural systems for switchgrass. Selected clones of woody species are producing dry weight yields in research plots on agricultural land that are 3 to 7 times greater than those obtained from mixed species stands on forest land, and at least 2 times the yields of southern plantation pines. Selected switchgrass varieties are producing dry weight yields 2 to 7 times greater than average forage grass yields on pasture and crop land. Crop development research is continuing efforts to translate this potential to commercial enterprises over a more geographically diverse acreage. Environmental research on biomass crops is aimed at developing sustainable systems that will contribute to the biodiversity of agricultural landscapes. Systems integration and analysis aim to understand all factors affecting price and potential supplies of biomass crops at regional and national scales. Scale-up studies, feasibility analysis and demonstrations are establishing actual costs and facilitating the commercialization of integrated biomass systems. Information management and dissemination activities are facilitating the communication of results among a community of researchers, policy-makers, and potential users and producers of energy crops. 15 refs.

  6. Future Diet Scenarios and Their Effect on Regional and Global Biofuel Potential

    NASA Astrophysics Data System (ADS)

    Gregg, J.; hvid, A.

    2012-04-01

    Food production has been one of the most significant ways in which humans have changed the surface of the Earth. It is projected that further intensification of agriculture will be necessary to meet a growing population and the increased demand for calories from animal products. This would require substantially more land and resources devoted to animal production. However, globally, the proportion of per capita caloric intake from animal to total caloric intake has remained relatively constant for the last 50 years at slightly above 15%. Nevertheless, there are large discrepancies across regions and through time. For example, northern European countries derive over 30% of calories from animal products, while India is under 10%; between 1961 and 2007, China's per capita consumption of animal calories has increased by over a factor of ten, while in the US, animal calorie consumption has remained constant. In general, per capita consumption of animal products is lower in developing countries than in developed countries, and it is commonly assumed that future animal product consumption will increase as developing countries become wealthier. On the other hand, wealthier countries are remaining constant or even decreasing their proportional consumption of animal calories, and this could be a different way that future diets may evolve. We create different future scenarios for calorie demand from vegetal products, beef, sheep and goat, pork, poultry, and dairy based on historical national trends and estimated income elasticities for these various food products. The extreme scenarios are one in which the world evolves to a highly vegetal calorie diet and, on the other extreme, one in which the world evolves to diets with high meat consumption. Intermediate scenarios include projections of current trends and one in which the world moves to a healthy balanced diet given current recommendations. Using DTU-GCAM, and global integrated assessment model with an included land use module, we explore the effect of these different global and regional diet scenarios on land use and biofuel potential up to the year 2095. The model economically optimizes food production for 14 different regions of the world based on their current and historical land use and land cover, using free market and free trade assumptions.

  7. Biofuel Database

    National Institute of Standards and Technology Data Gateway

    Biofuel Database (Web, free access)   This database brings together structural, biological, and thermodynamic data for enzymes that are either in current use or are being considered for use in the production of biofuels.

  8. Biofuels and Their Co-Products as Livestock Feed: Global Economic and Environmental Implications.

    PubMed

    Popp, József; Harangi-Rákos, Mónika; Gabnai, Zoltán; Balogh, Péter; Antal, Gabriella; Bai, Attila

    2016-01-01

    This review studies biofuel expansion in terms of competition between conventional and advanced biofuels based on bioenergy potential. Production of advanced biofuels is generally more expensive than current biofuels because products are not yet cost competitive. What is overlooked in the discussion about biofuel is the contribution the industry makes to the global animal feed supply and land use for cultivation of feedstocks. The global ethanol industry produces 44 million metric tonnes of high-quality feed, however, the co-products of biodiesel production have a moderate impact on the feed market contributing to just 8-9 million tonnes of protein meal output a year. By economically displacing traditional feed ingredients co-products from biofuel production are an important and valuable component of the biofuels sector and the global feed market. The return of co-products to the feed market has agricultural land use (and GHG emissions) implications as well. The use of co-products generated from grains and oilseeds can reduce net land use by 11% to 40%. The proportion of global cropland used for biofuels is currently some 2% (30-35 million hectares). By adding co-products substituted for grains and oilseeds the land required for cultivation of feedstocks declines to 1.5% of the global crop area. PMID:26938514

  9. Extremophiles in biofuel synthesis.

    PubMed

    Barnard, Desire; Casanueva, Ana; Tuffin, Marla; Cowan, Donald

    2010-01-01

    The current global energy situation has demonstrated an urgent need for the development of alternative fuel sources to the continually diminishing fossil fuel reserves. Much research to address this issue focuses on the development of financially viable technologies for the production of biofuels. The current market for biofuels, defined as fuel products obtained from organic substrates, is dominated by bioethanol, biodiesel, biobutanol and biogas, relying on the use of substrates such as sugars, starch and oil crops, agricultural and animal wastes, and lignocellulosic biomass. This conversion from biomass to biofuel through microbial catalysis has gained much momentum as biotechnology has evolved to its current status. Extremophiles are a robust group of organisms producing stable enzymes, which are often capable of tolerating changes in environmental conditions such as pH and temperature. The potential application of such organisms and their enzymes in biotechnology is enormous, and a particular application is in biofuel production. In this review an overview of the different biofuels is given, covering those already produced commercially as well as those under development. The past and present trends in biofuel production are discussed, and future prospects for the industry are highlighted. The focus is on the current and future application of extremophilic organisms and enzymes in technologies to develop and improve the biotechnological production of biofuels. PMID:20662378

  10. Greenhouse gas mitigation on marginal land: a quantitative review of the relative benefits of forest recovery versus biofuel production.

    PubMed

    Evans, Samuel G; Ramage, Benjamin S; DiRocco, Tara L; Potts, Matthew D

    2015-02-17

    Decisions concerning future land-use/land cover change stand at the forefront of ongoing debates on how to best mitigate climate change. In this study, we compare the greenhouse gas (GHG) mitigation value over a 30-year time frame for a range of forest recovery and biofuel production scenarios on abandoned agricultural land. Carbon sequestration in recovering forests is estimated based on a statistical analysis of tropical and temperate studies on marginal land. GHGs offset by biofuel production are analyzed for five different production pathways. We find that forest recovery is superior to low-yielding biofuel production scenarios such as oil palm and corn. Biofuel production scenarios with high yields, such as sugarcane or high-yielding energy grasses, can be comparable or superior to natural forest succession and to reforestation in some cases. This result stands in contrast to previous research suggesting that restoring degraded ecosystems to their native state is generally superior to agricultural production in terms of GHG mitigation. Further work is needed on carbon stock changes in forests, soil carbon dynamics, and bioenergy crop production on degraded/abandoned agricultural land. This finding also emphasizes the need to consider the full range of social, economic, and ecological consequences of land-use policies. PMID:25582654

  11. Landscape considerations of perennial biofuel feedstock production in conservation buffers of the Georgia Coastal Plain, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With global increases in the production of cellulosic biomass for fuel, or “biofuel,” concerns over potential negative effects of using land for biofuel production have promoted attention to concepts of agricultural landscape design that sustainably balance tradeoffs between food, fuel, fiber, and c...

  12. Sustainable multipurpose biorefineries for third-generation biofuels and value-added co-products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Modern biorefinery facilities conduct many types of processes, including those producing advanced biofuels, commodity chemicals, biodiesel, and value-added co-products such as sweeteners and bioinsecticides, with many more co-products, chemicals and biofuels on the horizon. Most of these processes ...

  13. Effect of shifting crop production for biofuel demand on soil and water quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of shifting cropping systems to dominantly corn for biofuels, in particular ethanol production, could have serious implications on soil and water quality. Proper land management for biofuels production in agriculture is critical to achieve because of maintaining the sustainability of lan...

  14. Life cycle and landscape impacts of biofuel production

    NASA Astrophysics Data System (ADS)

    Hill, J.

    2012-12-01

    Achieving the biofuel volumes mandated in the Renewable Fuels Standard of the United States Energy Independence and Security Act of 2007 will require large amounts of biomass such as crop residues and dedicated bioenergy crops. Growing sufficient amounts of these feedstocks would greatly transform the agricultural landscape of the United States, and depending on where and how they are grown, may have vastly different implications for the sustainability of the biofuels industry. This presentation describes ongoing research into how biomass can best be produced on the landscape so as to benefit rural economies and provide ecosystem services such as greenhouse gas mitigation and improved air quality. The focus is on newly developed methods for integrating spatial and temporal information into life cycle assessment so as to both allow for more detailed impact assessment and to provide insight into how to improve efficiency along bioenergy production supply chains. Results will benefit stakeholders both by offering recommendations for guiding sustainable growth of the emerging bioeconomy and by advancing understanding of the inherent tradeoffs among alternate scenarios.

  15. A Hydrologic Model to Quantify Large Scale Biofuel Production Impact on Upper Mississippi River Basin Water Quality

    NASA Astrophysics Data System (ADS)

    Demissie, Y. K.; Yan, E.; Wu, M.

    2010-12-01

    The projected increase in domestic ethanol production in the U.S. is expected to reduce greenhouse gas emissions, promote rural community development, and strengthen the nations energy security. However, its potential effect on water resources at both regional and local scales is still uncertain. Especially, changes in a large scale land use and management to produce high yield energy crops raised serious concern on its unintended potential impact on water quality and availability. This work presents a watershed modeling effort to establish a baseline condition for the Upper Mississippi River Basin, based on which impacts of conventional and cellulosic biofuel feedstock production on the region water resources will be evaluated. The watershed model was adequately calibrated and validated using eighteen years of observed water quality and stream discharge data. The models ability to estimate spatially and temporally varying crop growth and biomass production, which is essential to develop future biofuel productions scenarios, was evaluated based on the observed corn and soybean yields. The result validates the model ability to effectively simulate biomass productions from different bioenergy feedstock. A sensitivity analysis was further conducted to evaluate the calibrated model response to change in soil, crop properties, and fertilizer application rates associated with the expected increase in biofuel production. The results demonstrate non-linear, spatially-varying relationship among nitrate application rate, crop yield and nutrient loads, as well as soil and crop properties that are affected by increases in biofuel feedstock.

  16. Fatty acid synthesis in Escherichia coli and its applications towards the production of fatty acid based biofuels

    PubMed Central

    2014-01-01

    The idea of renewable and regenerative resources has inspired research for more than a hundred years. Ideally, the only spent energy will replenish itself, like plant material, sunlight, thermal energy or wind. Biodiesel or ethanol are examples, since their production relies mainly on plant material. However, it has become apparent that crop derived biofuels will not be sufficient to satisfy future energy demands. Thus, especially in the last decade a lot of research has focused on the production of next generation biofuels. A major subject of these investigations has been the microbial fatty acid biosynthesis with the aim to produce fatty acids or derivatives for substitution of diesel. As an industrially important organism and with the best studied microbial fatty acid biosynthesis, Escherichia coli has been chosen as producer in many of these studies and several reviews have been published in the fields of E. coli fatty acid biosynthesis or biofuels. However, most reviews discuss only one of these topics in detail, despite the fact, that a profound understanding of the involved enzymes and their regulation is necessary for efficient genetic engineering of the entire pathway. The first part of this review aims at summarizing the knowledge about fatty acid biosynthesis of E. coli and its regulation, and it provides the connection towards the production of fatty acids and related biofuels. The second part gives an overview about the achievements by genetic engineering of the fatty acid biosynthesis towards the production of next generation biofuels. Finally, the actual importance and potential of fatty acid-based biofuels will be discussed. PMID:24405789

  17. Fatty acid synthesis in Escherichia coli and its applications towards the production of fatty acid based biofuels.

    PubMed

    Janßen, Helge Jans; Steinbüchel, Alexander

    2014-01-01

    The idea of renewable and regenerative resources has inspired research for more than a hundred years. Ideally, the only spent energy will replenish itself, like plant material, sunlight, thermal energy or wind. Biodiesel or ethanol are examples, since their production relies mainly on plant material. However, it has become apparent that crop derived biofuels will not be sufficient to satisfy future energy demands. Thus, especially in the last decade a lot of research has focused on the production of next generation biofuels. A major subject of these investigations has been the microbial fatty acid biosynthesis with the aim to produce fatty acids or derivatives for substitution of diesel. As an industrially important organism and with the best studied microbial fatty acid biosynthesis, Escherichia coli has been chosen as producer in many of these studies and several reviews have been published in the fields of E. coli fatty acid biosynthesis or biofuels. However, most reviews discuss only one of these topics in detail, despite the fact, that a profound understanding of the involved enzymes and their regulation is necessary for efficient genetic engineering of the entire pathway. The first part of this review aims at summarizing the knowledge about fatty acid biosynthesis of E. coli and its regulation, and it provides the connection towards the production of fatty acids and related biofuels. The second part gives an overview about the achievements by genetic engineering of the fatty acid biosynthesis towards the production of next generation biofuels. Finally, the actual importance and potential of fatty acid-based biofuels will be discussed. PMID:24405789

  18. Synthetic biology for microbial production of lipid-based biofuels.

    PubMed

    d'Espaux, Leo; Mendez-Perez, Daniel; Li, Rachel; Keasling, Jay D

    2015-12-01

    The risks of maintaining current CO2 emission trends have led to interest in producing biofuels using engineered microbes. Microbial biofuels reduce emissions because CO2 produced by fuel combustion is offset by CO2 captured by growing biomass, which is later used as feedstock for biofuel fermentation. Hydrocarbons found in petroleum fuels share striking similarity with biological lipids. Here we review synthetic metabolic pathways based on fatty acid and isoprenoid metabolism to produce alkanes and other molecules suitable as biofuels. We further discuss engineering strategies to optimize engineered biosynthetic routes, as well as the potential of synthetic biology for sustainable manufacturing. PMID:26479184

  19. Optimization of light use efficiency for biofuel production in algae.

    PubMed

    Simionato, Diana; Basso, Stefania; Giacometti, Giorgio M; Morosinotto, Tomas

    2013-12-01

    A major challenge for next decades is development of competitive renewable energy sources, highly needed to compensate fossil fuels reserves and reduce greenhouse gas emissions. Among different possibilities, which are currently under investigation, there is the exploitation of unicellular algae for production of biofuels and biodiesel in particular. Some algae species have the ability of accumulating large amount of lipids within their cells which can be exploited as feedstock for the production of biodiesel. Strong research efforts are however still needed to fulfill this potential and optimize cultivation systems and biomass harvesting. Light provides the energy supporting algae growth and available radiation must be exploited with the highest possible efficiency to optimize productivity and make microalgae large scale cultivation energetically and economically sustainable. Investigation of the molecular bases influencing light use efficiency is thus seminal for the success of this biotechnology. In this work factors influencing light use efficiency in algal biomass production are reviewed, focusing on how algae genetic engineering and control of light environment within photobioreactors can improve the productivity of large scale cultivation systems. PMID:23876487

  20. A Dynamic Simulation of the Indirect Land Use Implications of Recent Biofuel Production and Use in the United States.

    SciTech Connect

    Oladosu, Gbadebo A; Kline, Keith L

    2013-01-01

    The global indirect land use change (ILUC) implications of biofuel use in the United States of America (USA) from 2001 to 2010 are evaluated with a dynamic general equilibrium model. The effects of biofuels production on agricultural land area vary by year; from a net expansion of 0.17 ha per 1000 gallons produced (2002) to a net contraction of 0.13 ha per 1000 gallons (2018) in Case 1 of our simulation. In accordance with the general narrative about the implications of biofuel policy, agricultural land area increased in many regions of the world. However, oil-export dependent economies experienced agricultural land contraction because of reductions in their revenues. Reducing crude oil imports is a major goal of biofuel policy, but the land use change implications have received little attention in the literature. Simulations evaluating the effects of doubling supply elasticities for land and fossil resources show that these parameters can significantly influence the land use change estimates. Therefore, research that provides empirically-based and spatially-detailed agricultural land-supply curves and capability to project future fossil energy prices is critical for improving estimates of the effects of biofuel policy on land use.

  1. Cyanobacterial chassis engineering for enhancing production of biofuels and chemicals.

    PubMed

    Gao, Xinyan; Sun, Tao; Pei, Guangsheng; Chen, Lei; Zhang, Weiwen

    2016-04-01

    To reduce dependence on fossil fuels and curb greenhouse effect, cyanobacteria have emerged as an important chassis candidate for producing biofuels and chemicals due to their capability to directly utilize sunlight and CO2 as the sole energy and carbon sources, respectively. Recent progresses in developing and applying various synthetic biology tools have led to the successful constructions of novel pathways of several dozen green fuels and chemicals utilizing cyanobacterial chassis. Meanwhile, it is increasingly recognized that in order to enhance productivity of the synthetic cyanobacterial systems, optimizing and engineering more robust and high-efficient cyanobacterial chassis should not be omitted. In recent years, numerous research studies have been conducted to enhance production of green fuels and chemicals through cyanobacterial chassis modifications involving photosynthesis, CO2 uptake and fixation, products exporting, tolerance, and cellular regulation. In this article, we critically reviewed recent progresses and universal strategies in cyanobacterial chassis engineering to make it more robust and effective for bio-chemicals production. PMID:26883347

  2. Use of tamarisk as a potential feedstock for biofuel production.

    SciTech Connect

    Sun, Amy Cha-Tien; Norman, Kirsten

    2011-01-01

    This study assesses the energy and water use of saltcedar (or tamarisk) as biomass for biofuel production in a hypothetical sub-region in New Mexico. The baseline scenario consists of a rural stretch of the Middle Rio Grande River with 25% coverage of mature saltcedar that is removed and converted to biofuels. A manufacturing system life cycle consisting of harvesting, transportation, pyrolysis, and purification is constructed for calculating energy and water balances. On a dry short ton woody biomass basis, the total energy input is approximately 8.21 mmBTU/st. There is potential for 18.82 mmBTU/st of energy output from the baseline system. Of the extractable energy, approximately 61.1% consists of bio-oil, 20.3% bio-char, and 18.6% biogas. Water consumptive use by removal of tamarisk will not impact the existing rate of evapotranspiration. However, approximately 195 gal of water is needed per short ton of woody biomass for the conversion of biomass to biocrude, three-quarters of which is cooling water that can be recovered and recycled. The impact of salt presence is briefly assessed. Not accounted for in the baseline are high concentrations of Calcium, Sodium, and Sulfur ions in saltcedar woody biomass that can potentially shift the relative quantities of bio-char and bio-oil. This can be alleviated by a pre-wash step prior to the conversion step. More study is needed to account for the impact of salt presence on the overall energy and water balance.

  3. Integrated Biorefineries with Engineered Microbes and High-value Co-products for Profitable Biofuels Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    First-generation (ie., corn-based) fuel ethanol production processes provide several advantages which could be synergistically applied to overcome limitations of second-generation biofuel processes from lignocellulose. These include resources such as equipment, manpower, nutrients, water, and heat....

  4. Production of bermudagrass for bio-fuels: effect of two genotypes on pyrolysis product yield

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bermudagrass is the perennial grass used as forage for livestock and harvested as hay on 10 to 15 million acres in Southern United States. It has potential as an energy crop for the production of biofuels through the lignocellulosic conversion program. Coastal was released in 1943 and was the pri...

  5. Methods of dealing with co-products of biofuels in life-cycle analysis and consequent results within the U.S. context.

    SciTech Connect

    Wang, M.; Huo, H.; Arora, S.

    2011-01-01

    Products other than biofuels are produced in biofuel plants. For example, corn ethanol plants produce distillers grains and solubles. Soybean crushing plants produce soy meal and soy oil, which is used for biodiesel production. Electricity is generated in sugarcane ethanol plants both for internal consumption and export to the electric grid. Future cellulosic ethanol plants could be designed to co-produce electricity with ethanol. It is important to take co-products into account in the life-cycle analysis of biofuels and several methods are available to do so. Although the International Standard Organization's ISO 14040 advocates the system boundary expansion method (also known as the 'displacement method' or the 'substitution method') for life-cycle analyses, application of the method has been limited because of the difficulty in identifying and quantifying potential products to be displaced by biofuel co-products. As a result, some LCA studies and policy-making processes have considered alternative methods. In this paper, we examine the available methods to deal with biofuel co-products, explore the strengths and weaknesses of each method, and present biofuel LCA results with different co-product methods within the U.S. context.

  6. USING GIS TO DETERMINE PLANTABLE AREA FOR PRAIRIE SWITCHGRASS BIOFUEL PRODUCTION IN KENTUCKY RIGHTS-OF-WAY

    EPA Science Inventory

    (1) The United States dependence on foreign fuel and other non-renewable resources has implications across disciplines including international relationships, the environment, and economics. Biofuels have been proposed as an alternative; however, land for biofuel product...

  7. USING GIS TO DETERMINE PLANTABLE AREA FOR PRAIRIE SWITCHGRASS BIOFUEL PRODUCTION IN KENTUCKY RIGHTS-OF-WAY

    EPA Science Inventory

    (1) The United States’ dependence on foreign fuel and other non-renewable resources has implications across disciplines including international relationships, the environment, and economics. Biofuels have been proposed as an alternative; however, land for biofuel product...

  8. From flavors and pharmaceuticals to advanced biofuels: production of isoprenoids in Saccharomyces cerevisiae.

    PubMed

    Tippmann, Stefan; Chen, Yun; Siewers, Verena; Nielsen, Jens

    2013-12-01

    Isoprenoids denote the largest group of chemicals in the plant kingdom and are employed for a wide range of applications in the food and pharmaceutical industry. In recent years, isoprenoids have additionally been recognized as suitable replacements for petroleum-derived fuels and could thus promote the transition towards a more sustainable society. To realize the biofuel potential of isoprenoids, a very efficient production system is required. While complex chemical structures as well as the low abundance in nature demonstrate the shortcomings of chemical synthesis and plant extraction, isoprenoids can be produced by genetically engineered microorganisms from renewable carbon sources. In this article, we summarize the development of isoprenoid applications from flavors and pharmaceuticals to advanced biofuels and review the strategies to design microbial cell factories, focusing on Saccharomyces cerevisiae for the production of these compounds. While the high complexity of biosynthetic pathways and the toxicity of certain isoprenoids still denote challenges that need to be addressed, metabolic engineering has enabled large-scale production of several terpenoids and thus, the utilization of these compounds is likely to expand in the future. PMID:24227704

  9. "Trojan Horse" strategy for deconstruction of biomass for biofuels production.

    SciTech Connect

    Sinclair, Michael B.; Hadi, Masood Z.; Timlin, Jerilyn Ann; Thomson, James; Whalen, Maureen; Thilmony, Roger; Tran-Gyamfi, Mary; Simmons, Blake Alexander; Sapra, Rajat

    2008-08-01

    Production of renewable biofuels to displace fossil fuels currently consumed in the transportation sector is a pressing multi-agency national priority. Currently, nearly all fuel ethanol is produced from corn-derived starch. Dedicated 'energy crops' and agricultural waste are preferred long-term solutions for renewable, cheap, and globally available biofuels as they avoid some of the market pressures and secondary greenhouse gas emission challenges currently facing corn ethanol. These sources of lignocellulosic biomass are converted to fermentable sugars using a variety of chemical and thermochemical pretreatments, which disrupt cellulose and lignin cross-links, allowing exogenously added recombinant microbial enzymes to more efficiently hydrolyze the cellulose for 'deconstruction' into glucose. This process is plagued with inefficiencies, primarily due to the recalcitrance of cellulosic biomass, mass transfer issues during deconstruction, and low activity of recombinant deconstruction enzymes. Costs are also high due to the requirement for enzymes and reagents, and energy-intensive and cumbersome pretreatment steps. One potential solution to these problems is found in synthetic biology; they propose to engineer plants that self-produce a suite of cellulase enzymes targeted to the apoplast for cleaving the linkages between lignin and cellulosic fibers; the genes encoding the degradation enzymes, also known as cellulases, are obtained from extremophilic organisms that grow at high temperatures (60-100 C) and acidic pH levels (<5). These enzymes will remain inactive during the life cycle of the plant but become active during hydrothermal pretreatment i.e., elevated temperatures. Deconstruction can be integrated into a one-step process, thereby increasing efficiency (cellulose-cellulase mass-transfer rates) and reducing costs. The proposed disruptive technologies address biomass deconstruction processes by developing transgenic plants encoding a suite of enzymes used in cellulosic deconstruction. The unique aspects of this technology are the rationally engineered, highly productive extremophilic enzymes, targeted to specific cellular locations (apoplast) and their dormancy during normal plant proliferation, which become Trojan horses during pretreatment conditions. They have been leveraging established Sandia's enzyme-engineering and imaging capabilities. Their technical approach not only targets the recalcitrance and mass-transfer problem during biomass degradation but also eliminates the costs associated with industrial-scale production of microbial enzymes added during processing.

  10. Biofuels from Microalgae: Review of Products, Processes and Potential, with Special Focus on Dunaliella sp.

    SciTech Connect

    Huesemann, Michael H.; Benemann, John R.

    2009-12-31

    There is currently great interest in using microalgae for the production of biofuels, mainly due to the fact that microalgae can produce biofuels at a much higher productivity than conventional plants and that they can be cultivated using water, in particular seawater, and land not competing for resources with conventional agriculture. However, at present such microalgae-based technologies are not yet developed and the economics of such processes are uncertain. We review power generation by direct combustion, production of hydrogen and other fuel gases and liquids by gasification and pyrolysis, methane generation by anaerobic digestion, ethanol fermentations, and hydrogen production by dark and light-driven metabolism. We in particular discuss the production of lipids, vegetable oils and hydrocarbons, which could be converted to biodiesel. Direct combustion for power generation has two major disadvantages in that the high N-content of algal biomass causes unacceptably high NOx emissions and losses of nitrogen fertilizer. Thus, the use of sun-dried microalgal biomass would not be cost-competitive with other solid fuels such as coal and wood. Thermochemical conversion processes such as gasification and pyrolysis have been successfully demonstrated in the laboratory but will be difficult to scale up commercially and suffers from similar, though sometimes not as stringent, limitations as combustion. Anaerobic digestion of microalgal cells yields only about 0.3 L methane per g volatile solids destroyed, about half of the maximum achievable, but yields can be increased by adding carbon rich substrates to circumvent ammonia toxicity caused by the N-rich algal biomass. Anaerobic digestion would be best suited for the treatment of algal biomass waste after value-added products have been separated. Algae can also be grown to accumulate starches or similar fermentable products, and ethanol or similar (e.g., butanol) fermentations could be applied to such biomass, but research is required on increasing solvent yields. Dark fermentation of algal biomass can also produce hydrogen, but, as for other fermentations, only at low yields. Hydrogen can also be generated by algae in the light, however, this process has not yet been demonstrated in any way that could be scaled up and, in any event, Dunaliella, is not known to produce hydrogen. In response to nutrient deficiency (nitrogen or silicon), some microalgae accumulate neutral lipids which, after physical extraction, could be converted, via transesterification with methanol, to biodiesel. Nitrogen-limitation does not appear to increase either cellular lipid content or lipid productivity in Dunaliella. Results from life cycle energy analyses indicate that cultivation of microalgal biomass in open raceway ponds has a positive energy output ratio (EOR), approaching up to 10 (i.e., the caloric energy output from the algae is 10 times greater than the fossil energy inputs), but EOR are less than 1 for biomass grown in engineered photobioreactors. Thus, from both an energetic as well as economic perspective, only open ponds systems can be considered. Significant long-term R&D will be required to make microalgal biofuels processes economically competitive. Specifically, future research should focus on (a) the improvement of biomass productivities (i.e., maximizing solar conversion efficiencies), (b) the selection and isolation of algal strains that can be mass cultured and maintained stably for long periods, (c) the production of algal biomass with a high content of lipids, carbohydrates, and co-products, at high productivity, (d) the low cost harvesting of the biomass, and (e) the extraction and conversion processes to actually derive the biofuels. For Dunaliella specifically, the highest potential is in the co-production of biofuels with high-value animal feeds based on their carotenoid content.

  11. Biofuel production: an odyssey from metabolic engineering to fermentation scale-up

    PubMed Central

    Hollinshead, Whitney; He, Lian; Tang, Yinjie J.

    2014-01-01

    Metabolic engineering has developed microbial cell factories that can convert renewable carbon sources into biofuels. Current molecular biology tools can efficiently alter enzyme levels to redirect carbon fluxes toward biofuel production, but low product yield and titer in large bioreactors prevent the fulfillment of cheap biofuels. There are three major roadblocks preventing economical biofuel production. First, carbon fluxes from the substrate dissipate into a complex metabolic network. Besides the desired product, microbial hosts direct carbon flux to synthesize biomass, overflow metabolites, and heterologous enzymes. Second, microbial hosts need to oxidize a large portion of the substrate to generate both ATP and NAD(P)H to power biofuel synthesis. High cell maintenance, triggered by the metabolic burdens from genetic modifications, can significantly affect the ATP supply. Thereby, fermentation of advanced biofuels (such as biodiesel and hydrocarbons) often requires aerobic respiration to resolve the ATP shortage. Third, mass transfer limitations in large bioreactors create heterogeneous growth conditions and micro-environmental fluctuations (such as suboptimal O2 level and pH) that induce metabolic stresses and genetic instability. To overcome these limitations, fermentation engineering should merge with systems metabolic engineering. Modern fermentation engineers need to adopt new metabolic flux analysis tools that integrate kinetics, hydrodynamics, and 13C-proteomics, to reveal the dynamic physiologies of the microbial host under large bioreactor conditions. Based on metabolic analyses, fermentation engineers may employ rational pathway modifications, synthetic biology circuits, and bioreactor control algorithms to optimize large-scale biofuel production. PMID:25071754

  12. Biofuel production: an odyssey from metabolic engineering to fermentation scale-up.

    PubMed

    Hollinshead, Whitney; He, Lian; Tang, Yinjie J

    2014-01-01

    Metabolic engineering has developed microbial cell factories that can convert renewable carbon sources into biofuels. Current molecular biology tools can efficiently alter enzyme levels to redirect carbon fluxes toward biofuel production, but low product yield and titer in large bioreactors prevent the fulfillment of cheap biofuels. There are three major roadblocks preventing economical biofuel production. First, carbon fluxes from the substrate dissipate into a complex metabolic network. Besides the desired product, microbial hosts direct carbon flux to synthesize biomass, overflow metabolites, and heterologous enzymes. Second, microbial hosts need to oxidize a large portion of the substrate to generate both ATP and NAD(P)H to power biofuel synthesis. High cell maintenance, triggered by the metabolic burdens from genetic modifications, can significantly affect the ATP supply. Thereby, fermentation of advanced biofuels (such as biodiesel and hydrocarbons) often requires aerobic respiration to resolve the ATP shortage. Third, mass transfer limitations in large bioreactors create heterogeneous growth conditions and micro-environmental fluctuations (such as suboptimal O2 level and pH) that induce metabolic stresses and genetic instability. To overcome these limitations, fermentation engineering should merge with systems metabolic engineering. Modern fermentation engineers need to adopt new metabolic flux analysis tools that integrate kinetics, hydrodynamics, and (13)C-proteomics, to reveal the dynamic physiologies of the microbial host under large bioreactor conditions. Based on metabolic analyses, fermentation engineers may employ rational pathway modifications, synthetic biology circuits, and bioreactor control algorithms to optimize large-scale biofuel production. PMID:25071754

  13. Trade-offs of water use for hydropower generation and biofuel production in the Zambezi basin in Mozambique

    NASA Astrophysics Data System (ADS)

    Stanzel, Philipp; Kling, Harald; Nicholson, Kit

    2014-05-01

    Hydropower is the most important energy source in Mozambique, as in many other southern African countries. In the Zambezi basin, it is one of the major economic resources, and substantial hydropower development is envisaged for the next decades. In Mozambique, the extension of the large Cahora Bassa hydropower plant and the construction of several new facilities downstream are planned. Irrigated agriculture currently plays a minor role, but has a large potential due to available land and water resources. Irrigation development, especially for the production of biofuels, is an important government policy goal in Mozambique. This contribution assesses interrelations and trade-offs between these two development options with high dependence on water availability. Potential water demand for large-scale irrigated agriculture is estimated for a mix of possible biofuel crops in three scenarios with different irrigated area sizes. Impacts on river discharge and hydropower production in the Lower Zambezi and its tributaries under two projected future climates are simulated with a hydrological model and a reservoir operation and hydropower model. Trade-offs of increasing biofuel production with decreasing hydropower generation due to diminished discharge in the Zambezi River are investigated based on potential energy production, from hydropower and biofuels, and resulting gross revenues and net benefits. Results show that the impact of irrigation withdrawal on hydropower production is rather low due to the generally high water availability in the Zambezi River. In simulations with substantial irrigated areas, hydropower generation decreases by -2% as compared to a scenario with only small irrigated areas. The economic analyses suggest that the use of water for cultivation of biofuel crops in the Zambezi basin can generate higher economic benefits than the use of water for hydroelectric power production. If world oil prices stay at more than about 80 USD/barrel, then the production of biofuels for oil import substitution will yield strong benefits except for the least efficient producers. Producing biofuels for export is more challenging and requires highly efficient production. Generally, investment in irrigated agriculture is expected to have more impact on local economy and therefore poverty reduction than investment in hydropower development.

  14. Slab waveguide photobioreactors for microalgae based biofuel production.

    PubMed

    Jung, Erica Eunjung; Kalontarov, Michael; Doud, Devin F R; Ooms, Matthew D; Angenent, Largus T; Sinton, David; Erickson, David

    2012-10-01

    Microalgae are a promising feedstock for sustainable biofuel production. At present, however, there are a number of challenges that limit the economic viability of the process. Two of the major challenges are the non-uniform distribution of light in photobioreactors and the inefficiencies associated with traditional biomass processing. To address the latter limitation, a number of studies have demonstrated organisms that directly secrete fuels without requiring organism harvesting. In this paper, we demonstrate a novel optofluidic photobioreactor that can help address the light distribution challenge while being compatible with these chemical secreting organisms. Our approach is based on light delivery to surface bound photosynthetic organisms through the evanescent field of an optically excited slab waveguide. In addition to characterizing organism growth-rates in the system, we also show here, for the first time, that the photon usage efficiency of evanescent field illumination is comparable to the direct illumination used in traditional photobioreactors. We also show that the stackable nature of the slab waveguide approach could yield a 12-fold improvement in the volumetric productivity. PMID:22824859

  15. Development of biological platform for the autotrophic production of biofuels

    NASA Astrophysics Data System (ADS)

    Khan, Nymul

    The research described herein is aimed at developing an advanced biofuel platform that has the potential to surpass the natural rate of solar energy capture and CO2 fixation. The underlying concept is to use the electricity from a renewable source, such as wind or solar, to capture CO 2 via a biological agent, such as a microbe, into liquid fuels that can be used for the transportation sector. In addition to being renewable, the higher rate of energy capture by photovoltaic cells than natural photosynthesis is expected to facilitate higher rate of liquid fuel production than traditional biofuel processes. The envisioned platform is part of ARPA-E's (Advanced Research Projects Agency - Energy) Electrofuels initiative which aims at supplementing the country's petroleum based fuel production with renewable liquid fuels that can integrate easily with the existing refining and distribution infrastructure (http://arpae. energy.gov/ProgramsProjects/Electrofuels.aspx). The Electrofuels initiative aimed to develop liquid biofuels that avoid the issues encountered in the current generation of biofuels: (1) the reliance of biomass-derived technologies on the inefficient process of photosynthesis, (2) the relatively energy- and resource-intensive nature of agronomic processes, and (3) the occupation of large areas of arable land for feedstock production. The process proceeds by the capture of solar energy into electrical energy via photovoltaic cells, using the generated electricity to split water into molecular hydrogen (H2) and oxygen (O2), and feeding these gases, along with carbon dioxide (CO2) emitted from point sources such as a biomass or coal-fired power plant, to a microbial bioprocessing platform. The proposed microbial bioprocessing platform leverages a chemolithoautotrophic microorganism (Rhodobacter capsulatus or Ralstonia eutropha) naturally able to utilize these gases as growth substrates, and genetically modified to produce a triterpene hydrocarbon fuel molecule (C30+ botryococcenes) native to the alga Botryococcus braunii . In addition to the genetic modification and bioreactor performance studies of these organisms for the production of botryococcene or squalene, the research examined the potential economic feasibility of the proposed platform through the use of bioreactor, microbial energetic models and experimentally measured growth yield and maintenance coefficients. In order to carry out an economic analysis, a process model was created in Aspen with the bioreactor at the center. This is presented in Chapter 2. The model looked at the effects of growth yield and maintenance coefficients of R. capsulatus and R. eutropha, reactor residence time, gas-liquid mass-transfer coefficients, gas composition and specific fuel productivity on the volumetric productivity and fuel yield on H2. It was found that the organism with the lowest maintenance coefficient performed better under very low growth rates evaluated in the model (based on residence time through the reactor) performed the best. The optimum parameter values were then used to determine the capital and operating costs for a 5000 bbl-fuel/day plant and the final fuel cost based on the Levelized Cost of Electricity (LCOE). It was found that under the assumptions used in this analysis and crude oil prices, the LCOE required for economic feasibility must be less than 2¢/kWh. While not feasible under current market prices and costs, this work identifies key variables impacting process cost and discusses potential alternative paths toward economic feasibility. This was the best case scenario of the two organisms evaluated, and an optimally suited organism with high growth yield and low maintenance coefficient should obviously improve the economics. This economic constraint will improve with the rise of fossil fuel prices, which should occur if the environmentally detrimental effects of their use are factored into the price, through higher taxation, for example. A review of the current status of metabolic engineering of chemolithoautotrophs is carried out in order to identify the challenges and likely routes to overcome them. This is presented in Chapter 3 of this dissertation. The initial metabolic engineering and bioreactor studies was carried out using a number of gene-constructs on R. capsulatus and R. eutropha. The gene-constructs consisted of Plac promoter followed by the triterpene synthase genes (SS or BS) and other upstream genes. A comparison of the production of triterpenes were done in the different growth modes that R. capsulatus was capable of growing---aerobic heterotrophic, anaerobic photoheterotrophic and aerobic chemoautotrophic. Autotrophic productivity could likely be improved much further by increasing the available mass-transfer of the reactor. These efforts are presented in Chapter 4 of this dissertation. (Abstract shortened by UMI.).

  16. Metabolic engineering of microorganisms for biofuels production: from bugs to synthetic biology to fuels

    SciTech Connect

    Kuk Lee, Sung; Chou, Howard; Ham, Timothy S.; Soon Lee, Taek; Keasling, Jay D.

    2009-12-02

    The ability to generate microorganisms that can produce biofuels similar to petroleum-based transportation fuels would allow the use of existing engines and infrastructure and would save an enormous amount of capital required for replacing the current infrastructure to accommodate biofuels that have properties significantly different from petroleum-based fuels. Several groups have demonstrated the feasibility of manipulating microbes to produce molecules similar to petroleum-derived products, albeit at relatively low productivity (e.g. maximum butanol production is around 20 g/L). For cost-effective production of biofuels, the fuel-producing hosts and pathways must be engineered and optimized. Advances in metabolic engineering and synthetic biology will provide new tools for metabolic engineers to better understand how to rewire the cell in order to create the desired phenotypes for the production of economically viable biofuels.

  17. The economic prospects of cellulosic biomass for biofuel production

    NASA Astrophysics Data System (ADS)

    Kumarappan, Subbu

    Alternative fuels for transportation have become the focus of intense policy debate and legislative action due to volatile oil prices, an unstable political environment in many major oil producing regions, increasing global demand, dwindling reserves of low-cost oil, and concerns over global warming. A major potential source of alternative fuels is biofuels produced from cellulosic biomass, which have a number of potential benefits. Recognizing these potential advantages, the Energy Independence and Security Act of 2007 has mandated 21 billion gallons of cellulosic/advanced biofuels per year by 2022. The United States needs 220-300 million tons of cellulosic biomass per year from the major sources such as agricultural residues, forestry and mill residues, herbaceous resources, and waste materials (supported by Biomass Crop Assistance Program) to meet these biofuel targets. My research addresses three key major questions concerning cellulosic biomass supply. The first paper analyzes cellulosic biomass availability in the United States and Canada. The estimated supply curves show that, at a price of 100 per ton, about 568 million metric tons of biomass is available in the United States, while 123 million metric tons is available in Canada. In fact, the 300 million tons of biomass required to meet EISA mandates can be supplied at a price of 50 per metric ton or lower. The second paper evaluates the farmers' perspective in growing new energy crops, such as switchgrass and miscanthus, in prime cropland, in pasture areas, or on marginal lands. My analysis evaluates how the farmers' returns from energy crops compare with those from other field crops and other agricultural land uses. The results suggest that perennial energy crops yielding at least 10 tons per acre annually will be competitive with a traditional corn-soybean rotation if crude oil prices are high (ranging from 88-178 per barrel over 2010-2019). If crude oil prices are low, then energy crops will not be competitive with existing crops, and additional subsidy support would be required. Among the states in the eastern half of US, the states of Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Virginia are found to be economically more suitable to cultivate perennial energy crops. The third paper estimates the optimal feedstock composition of annual and perennial feedstocks from a biorefinery's perspective. The objective function of the optimization model is to minimize the cumulative costs covering harvesting, transport, storage, and GHG costs, of biomass procurement over a biorefinery's productive period of 20 years subject to various constraints on land availability, feedstock availability, processing capacity, contracting needs and storage. The results suggest that the economic tradeoff is between higher production costs for dedicated energy crops and higher collection and transport costs for agricultural residues; the delivered costs of biomass drives the results. These tradeoffs are reflected in optimal spatial planting pattern as preferred by the biorefinery: energy crops are grown in fields closer to the biorefinery and agricultural residues can be sourced from fields farther away from the biorefinery. The optimization model also provides useful insights into the price premiums paid for annual and perennial feedstocks. For the parameters used in the case study, the energy crop price premium ranges from 2 to 8 per ton for fields located within a 10 mile radius. For agricultural residues, the price premiums range from 5 to 16 per ton within a 10-20 mile radius.

  18. Plant cell wall engineering: applications in biofuel production and improved human health.

    PubMed

    Burton, Rachel A; Fincher, Geoffrey B

    2014-04-01

    Plant cell walls consist largely of cellulose, non-cellulosic polysaccharides and lignin. Concerted attempts are underway to convert wall polysaccharides from crop plant residues into renewable transport fuels and other valuable products, and to exploit the dietary benefits of cereal grain wall polysaccharides in human health. Attempts to improve plant performance for these applications have involved the manipulation of the levels and structures of wall components. Some successes in altering non-cellulosic polysaccharides has been achieved, but it would appear that drastic changes in cellulose are more difficult to engineer. Nevertheless, future prospects for both genetically modified (GM) and non-GM technologies to modify plant cell wall composition and structure remain bright, and will undoubtedly find applications beyond the current focus on human health and biofuel production. PMID:24679262

  19. BIOWINOL TECHNOLOGIES: A HYBRID GREEN PROCESS FOR BIOFUEL PRODUCTION – PHASE 2

    EPA Science Inventory

    The development of hollow fiber membrane (HFM) reactor will result in improved gas utilization that will positively impact overall process efficiencies. Successful completion of this project could result in the development of many decentralized biofuel production systems near ...

  20. Comprehensive techno-economic analysis of wastewater-based algal biofuel production: A case study.

    PubMed

    Xin, Chunhua; Addy, Min M; Zhao, Jinyu; Cheng, Yanling; Cheng, Sibo; Mu, Dongyan; Liu, Yuhuan; Ding, Rijia; Chen, Paul; Ruan, Roger

    2016-07-01

    Combining algae cultivation and wastewater treatment for biofuel production is considered the feasible way for resource utilization. An updated comprehensive techno-economic analysis method that integrates resources availability into techno-economic analysis was employed to evaluate the wastewater-based algal biofuel production with the consideration of wastewater treatment improvement, greenhouse gases emissions, biofuel production costs, and coproduct utilization. An innovative approach consisting of microalgae cultivation on centrate wastewater, microalgae harvest through flocculation, solar drying of biomass, pyrolysis of biomass to bio-oil, and utilization of co-products, was analyzed and shown to yield profound positive results in comparison with others. The estimated break even selling price of biofuel ($2.23/gallon) is very close to the acceptable level. The approach would have better overall benefits and the internal rate of return would increase up to 18.7% if three critical components, namely cultivation, harvest, and downstream conversion could achieve breakthroughs. PMID:27039331

  1. BIOWINOL TECHNOLOGIES: A HYBRID GREEN PROCESS FOR BIOFUEL PRODUCTION PHASE 2

    EPA Science Inventory

    The development of hollow fiber membrane (HFM) reactor will result in improved gas utilization that will positively impact overall process efficiencies. Successful completion of this project could result in the development of many decentralized biofuel production systems near ...

  2. Assessing regional hydrology and water quality implications of large-scale biofuel feedstock production in the Upper Mississippi River Basin.

    PubMed

    Demissie, Yonas; Yan, Eugene; Wu, May

    2012-08-21

    A recent U.S. Department of Energy study estimated that more than one billion tons of biofuel feedstock could be produced by 2030 in the United States from increased corn yield, and changes in agricultural and forest residue management and land uses. To understand the implications of such increased production on water resources and stream quality at regional and local scales, we have applied a watershed model for the Upper Mississippi River Basin, where most of the current and future crop/residue-based biofuel production is expected. The model simulates changes in water quality (soil erosion, nitrogen and phosphorus loadings in streams) and resources (soil-water content, evapotranspiration, and runoff) under projected biofuel production versus the 2006 baseline year and a business-as-usual scenario. The basin average results suggest that the projected feedstock production could change the rate of evapotranspiration in the UMRB by approximately +2%, soil-water content by about -2%, and discharge to streams by -5% from the baseline scenario. However, unlike the impacts on regional water availability, the projected feedstock production has a mixed effect on water quality, resulting in 12% and 45% increases in annual suspended sediment and total phosphorus loadings, respectively, but a 3% decrease in total nitrogen loading. These differences in water quantity and quality are statistically significant (p < 0.05). The basin responses are further analyzed at monthly time steps and finer spatial scales to evaluate underlying physical processes, which would be essential for future optimization of environmentally sustainable biofuel productions. PMID:22827327

  3. Membranes with artificial free-volume for biofuel production

    PubMed Central

    Petzetakis, Nikos; Doherty, Cara M.; Thornton, Aaron W.; Chen, X. Chelsea; Cotanda, Pepa; Hill, Anita J.; Balsara, Nitash P.

    2015-01-01

    Free-volume of polymers governs transport of penetrants through polymeric films. Control over free-volume is thus important for the development of better membranes for a wide variety of applications such as gas separations, pharmaceutical purifications and energy storage. To date, methodologies used to create materials with different amounts of free-volume are based primarily on chemical synthesis of new polymers. Here we report a simple methodology for generating free-volume based on the self-assembly of polyethylene-b-polydimethylsiloxane-b-polyethylene triblock copolymers. We have used this method to fabricate a series of membranes with identical compositions but with different amounts of free-volume. We use the term artificial free-volume to refer to the additional free-volume created by self-assembly. The effect of artificial free-volume on selective transport through the membranes was tested using butanol/water and ethanol/water mixtures due to their importance in biofuel production. We found that the introduction of artificial free-volume improves both alcohol permeability and selectivity. PMID:26104672

  4. Engineering ionic liquid-tolerant cellulases for biofuels production.

    PubMed

    Wolski, Paul W; Dana, Craig M; Clark, Douglas S; Blanch, Harvey W

    2016-04-01

    Dissolution of lignocellulosic biomass in certain ionic liquids (ILs) can provide an effective pretreatment prior to enzymatic saccharification of cellulose for biofuels production. Toward the goal of combining pretreatment and enzymatic hydrolysis, we evolved enzyme variants of Talaromyces emersonii Cel7A to be more active and stable than wild-type T. emersonii Cel7A or Trichoderma reesei Cel7A in aqueous-IL solutions (up to 43% (w/w) 1,3-dimethylimdazolium dimethylphosphate and 20% (w/w) 1-ethyl-3-methylimidazolium acetate). In general, greater enzyme stability in buffer at elevated temperature corresponded to greater stability in aqueous-ILs. Post-translational modification of the N-terminal glutamine residue to pyroglutamate via glutaminyl cyclase enhanced the stability of T. emersonii Cel7A and variants. Differential scanning calorimetry revealed an increase in melting temperature of 1.9-3.9°C for the variant 1M10 over the wild-type T. emersonii Cel7A in aqueous buffer and in an IL-aqueous mixture. We observed this increase both with and without glutaminyl cyclase treatment of the enzymes. PMID:26819239

  5. Atmospheric emission of reactive nitrogen during biofuel ethanol production.

    PubMed

    Machado, Cristine M D; Cardoso, Arnaldo A; Allen, Andrew G

    2008-01-15

    This paper evaluates emissions to the atmosphere of biologically available nitrogen compounds in a region characterized by intensive sugar cane biofuel ethanol production. Large emissions of NH3 and NOx, as well as particulate nitrate and ammonium, occur at the harvest when the crop is burned, with the amount of nitrogen released equivalent to approximately 35% of annual fertilizer-N application. Nitrogen oxides concentrations show a positive association with fire frequency, indicating that biomass burning is a major emission source, with mean concentrations of NOx doubling in the dry season relative to the wetseason. During the dry season biomass burning is a source of NH3, with other sources (wastes, soil, biogenic) predominant during the wet season. Estimated NO2-N, NH3-N, NO3- -N and NH4+ -N emission fluxes from sugar cane burning in a planted area of ca. 2.2 x 10(6) ha are 11.0, 1.1, 0.2, and 1.2 Gg N yr(-1), respectively. PMID:18284134

  6. Membranes with artificial free-volume for biofuel production.

    PubMed

    Petzetakis, Nikos; Doherty, Cara M; Thornton, Aaron W; Chen, X Chelsea; Cotanda, Pepa; Hill, Anita J; Balsara, Nitash P

    2015-01-01

    Free-volume of polymers governs transport of penetrants through polymeric films. Control over free-volume is thus important for the development of better membranes for a wide variety of applications such as gas separations, pharmaceutical purifications and energy storage. To date, methodologies used to create materials with different amounts of free-volume are based primarily on chemical synthesis of new polymers. Here we report a simple methodology for generating free-volume based on the self-assembly of polyethylene-b-polydimethylsiloxane-b-polyethylene triblock copolymers. We have used this method to fabricate a series of membranes with identical compositions but with different amounts of free-volume. We use the term artificial free-volume to refer to the additional free-volume created by self-assembly. The effect of artificial free-volume on selective transport through the membranes was tested using butanol/water and ethanol/water mixtures due to their importance in biofuel production. We found that the introduction of artificial free-volume improves both alcohol permeability and selectivity. PMID:26104672

  7. Membranes with artificial free-volume for biofuel production

    NASA Astrophysics Data System (ADS)

    Petzetakis, Nikos; Doherty, Cara M.; Thornton, Aaron W.; Chen, X. Chelsea; Cotanda, Pepa; Hill, Anita J.; Balsara, Nitash P.

    2015-06-01

    Free-volume of polymers governs transport of penetrants through polymeric films. Control over free-volume is thus important for the development of better membranes for a wide variety of applications such as gas separations, pharmaceutical purifications and energy storage. To date, methodologies used to create materials with different amounts of free-volume are based primarily on chemical synthesis of new polymers. Here we report a simple methodology for generating free-volume based on the self-assembly of polyethylene-b-polydimethylsiloxane-b-polyethylene triblock copolymers. We have used this method to fabricate a series of membranes with identical compositions but with different amounts of free-volume. We use the term artificial free-volume to refer to the additional free-volume created by self-assembly. The effect of artificial free-volume on selective transport through the membranes was tested using butanol/water and ethanol/water mixtures due to their importance in biofuel production. We found that the introduction of artificial free-volume improves both alcohol permeability and selectivity.

  8. The Implications of Biofuel Production on Soil Productivity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Production of biomass from agricultural crops as a source of energy generated either as a primary or secondary source from agricultural systems has the potential to provide a portion of the nation’s energy needs. Removal of crop residue after harvest is viewed as a major source of cellulosic materia...

  9. Water use impacts of future transport fuels: role of California's climate policy & National biofuel policies (Invited)

    NASA Astrophysics Data System (ADS)

    Teter, J.; Yeh, S.; Mishra, G. S.; Tiedeman, K.; Yang, C.

    2013-12-01

    In the coming decades, growing demand for energy and water and the need to address climate change will create huge challenges for energy policy and natural resource management. Synergistic strategies must be developed to conserve and use both resources more efficiently. California (CA) is a prime example of a region where policymakers have began to incorporate water planning in energy infrastructure development. But more must be done as CA transforms its energy system to meet its climate target. We analyze lifecycle water use of current and future transport fuel consumption to evaluate impacts & formulate mitigation strategies for the state at the watershed scale. Four 'bounding cases' for CA's future transportation demand to year 2030 are projected for analysis: two scenarios that only meet the 2020 climate target (business-as-usual, BAU) with high / low water use intensity, and two that meet long-term climate target with high / low water use intensity (Fig 1). Our study focuses on the following energy supply chains: (a) liquid fuels from conventional/unconventional oil & gas, (b) thermoelectric and renewable generation technologies, and (c) biofuels (Fig 2-3). We develop plausible siting scenarios that bound the range of possible water sources, impacts, and dispositions to provide insights into how to best allocate water and limit water impacts of energy development. We further identify constraints & opportunities to improve water use efficiency and highlight salient policy relevant lessons. For biofuels we extend our scope to the entire US as most of the biofuels consumed in California are and will be produced from outside of the state. We analyze policy impacts that capture both direct & indirect land use effects across scenarios, thus addressing the major shortcomings of existing studies, which ignore spatial heterogeneity as well as economic effects of crop displacement and the effects of crop intensification and extensification. We use the agronomic-hydrologic model EPIC to capture both green water (GW) and blue water (BW) use at a ~10 square km resolution among three scenarios: (1) a counterfactual scenario with no national biofuel policy, (2) current Renewable Fuels Standard (RFS) mandates, and (3) a proposed national Low Carbon Fuel Standard (LCFS) plus the RFS scenario. Inputs to EPIC are spatially explicit: (a) cropping areas and yields as projected by a partial equilibrium economic model, (b) daily weather data, (c) soil properties (d) N fertilizer application, and (e) irrigation sources and volumes, by crop (Fig 4-5). We assess the differences among biofuel scenarios from 2007-2035 along the following metrics: (1) crop area expansion on prime & marginal lands (Fig 6), (2) Crop-specific & overall annual/seasonal water balances including (2a) water inflows (irrigation & precipitation), (2b) crop-atmosphere interactions: (evaporation & transpiration) and (2c) soil-water flows (runoff & soil infiltration), in mm3 /acre. We found differential water use impacts among biofuel scenarios are a primarily a function of (1) land use conversion, in particular that of formerly uncropped land classes (2) irrigation practices, (3) feedstock water use efficiency, and (4) the longer growing season and a predominance of rainfed cultivation of dedicated biofuel feedstocks. Fig 1-6 available at the linked urls.

  10. Chlamydomonas as a model for biofuels and bio-products production.

    PubMed

    Scranton, Melissa A; Ostrand, Joseph T; Fields, Francis J; Mayfield, Stephen P

    2015-05-01

    Developing renewable energy sources is critical to maintaining the economic growth of the planet while protecting the environment. First generation biofuels focused on food crops like corn and sugarcane for ethanol production, and soybean and palm for biodiesel production. Second generation biofuels based on cellulosic ethanol produced from terrestrial plants, has received extensive funding and recently pilot facilities have been commissioned, but to date output of fuels from these sources has fallen well short of what is needed. Recent research and pilot demonstrations have highlighted the potential of algae as one of the most promising sources of sustainable liquid transportation fuels. Algae have also been established as unique biofactories for industrial, therapeutic, and nutraceutical co-products. Chlamydomonas reinhardtii's long established role in the field of basic research in green algae has paved the way for understanding algal metabolism and developing genetic engineering protocols. These tools are now being utilized in C. reinhardtii and in other algal species for the development of strains to maximize biofuels and bio-products yields from the lab to the field. PMID:25641390

  11. Natural Oil Production from Microorganisms: Bioprocess and Microbe Engineering for Total Carbon Utilization in Biofuel Production

    SciTech Connect

    2010-07-15

    Electrofuels Project: MIT is using carbon dioxide (CO2) and hydrogen generated from electricity to produce natural oils that can be upgraded to hydrocarbon fuels. MIT has designed a 2-stage biofuel production system. In the first stage, hydrogen and CO2 are fed to a microorganism capable of converting these feedstocks to a 2-carbon compound called acetate. In the second stage, acetate is delivered to a different microorganism that can use the acetate to grow and produce oil. The oil can be removed from the reactor tank and chemically converted to various hydrocarbons. The electricity for the process could be supplied from novel means currently in development, or more proven methods such as the combustion of municipal waste, which would also generate the required CO2 and enhance the overall efficiency of MIT’s biofuel-production system.

  12. A comprehensive review of biomass resources and biofuel production in Nigeria: potential and prospects.

    PubMed

    Sokan-Adeaga, Adewale Allen; Ana, Godson R E E

    2015-08-01

    The quest for biofuels in Nigeria, no doubt, represents a legitimate ambition. This is so because the focus on biofuel production has assumed a global dimension, and the benefits that may accrue from such effort may turn out to be enormous if the preconditions are adequately satisfied. As a member of the global community, it has become exigent for Nigeria to explore other potential means of bettering her already impoverished economy. Biomass is the major energy source in Nigeria, contributing about 78% of Nigeria's primary energy supply. In this paper, a comprehensive review of the potential of biomass resources and biofuel production in Nigeria is given. The study adopted a desk review of existing literatures on major energy crops produced in Nigeria. A brief description of the current biofuel developmental activities in the country is also given. A variety of biomass resources exist in the country in large quantities with opportunities for expansion. Biomass resources considered include agricultural crops, agricultural crop residues, forestry resources, municipal solid waste, and animal waste. However, the prospects of achieving this giant stride appear not to be feasible in Nigeria. Although the focus on biofuel production may be a worthwhile endeavor in view of Nigeria's development woes, the paper argues that because Nigeria is yet to adequately satisfy the preconditions for such program, the effort may be designed to fail after all. To avoid this, the government must address key areas of concern such as food insecurity, environmental crisis, and blatant corruption in all quarters. It is concluded that given the large availability of biomass resources in Nigeria, there is immense potential for biofuel production from these biomass resources. With the very high potential for biofuel production, the governments as well as private investors are therefore encouraged to take practical steps toward investing in agriculture for the production of energy crops and the establishment of biofuel-processing plants in Nigeria. PMID:26351798

  13. The value of biodiversity in legume symbiotic nitrogen fixation and nodulation for biofuel and food production.

    PubMed

    Gresshoff, Peter M; Hayashi, Satomi; Biswas, Bandana; Mirzaei, Saeid; Indrasumunar, Arief; Reid, Dugald; Samuel, Sharon; Tollenaere, Alina; van Hameren, Bethany; Hastwell, April; Scott, Paul; Ferguson, Brett J

    2015-01-01

    Much of modern agriculture is based on immense populations of genetically identical or near-identical varieties, called cultivars. However, advancement of knowledge, and thus experimental utility, is found through biodiversity, whether naturally-found or induced by the experimenter. Globally we are confronted by ever-growing food and energy challenges. Here we demonstrate how such biodiversity from the food legume crop soybean (Glycine max L. Merr) and the bioenergy legume tree Pongamia (Millettia) pinnata is a great value. Legume plants are diverse and are represented by over 18,000 species on this planet. Some, such as soybean, pea and medics are used as food and animal feed crops. Others serve as ornamental (e.g., wisteria), timber (e.g., acacia/wattle) or biofuel (e.g., Pongamia pinnata) resources. Most legumes develop root organs (nodules) after microsymbiont induction that serve as their habitat for biological nitrogen fixation. Through this, nitrogen fertiliser demand is reduced by the efficient symbiosis between soil Rhizobium-type bacteria and the appropriate legume partner. Mechanistic research into the genetics, biochemistry and physiology of legumes is thus strategically essential for future global agriculture. Here we demonstrate how molecular plant science analysis of the genetics of an established food crop (soybean) and an emerging biofuel P. pinnata feedstock contributes to their utility by sustainable production aided by symbiotic nitrogen fixation. PMID:25240795

  14. NREL's Cyanobacteria Engineering Shortens Biofuel Production Process, Captures CO2

    SciTech Connect

    2015-09-01

    This highlight describes NREL's work to systematically analyze the flow of energy in a photosynthetic microbe and show how the organism adjusts its metabolism to meet the increased energy demand for making ethylene. This work successfully demonstrates that the organism could cooperate by stimulating photosynthesis. The results encourage further genetic engineering for the conversion of CO2 to biofuels and chemicals. This highlight is being developed for the September 2015 Alliance S&T Board meeting. biofuels and chemicals. This highlight is being developed for the September 2015 Alliance S&T Board meeting.

  15. Methodology for calculation of carbon balances for biofuel crops production

    NASA Astrophysics Data System (ADS)

    Gerlfand, I.; Hamilton, S. K.; Snapp, S. S.; Robertson, G. P.

    2012-04-01

    Understanding the carbon balance implications for different biofuel crop production systems is important for the development of decision making tools and policies. We present here a detailed methodology for assessing carbon balances in agricultural and natural ecosystems. We use 20 years of data from Long-term Ecological Research (LTER) experiments at the Kellogg Biological Station (KBS), combined with models to produce farm level CO2 balances for different management practices. We compared four grain and one forage systems in the U.S. Midwest: corn (Zea mays) - soybean (Glycine max) - wheat (Triticum aestivum) rotations managed with (1) conventional tillage, (2) no till, (3) low chemical input, and (4) biologically-based (organic) practices; and (5) continuous alfalfa (Medicago sativa). In addition we use an abandoned agricultural field (successionnal ecosystem) as reference system. Measurements include fluxes of N2O and CH4, soil organic carbon change, agricultural yields, and agricultural inputs (e.g. fertilization and farm fuel use). In addition to measurements, we model carbon offsets associated with the use of bioenergy from agriculturally produced crops. Our analysis shows the importance of establishing appropriate system boundaries for carbon balance calculations. We explore how different assumptions regarding production methods and emission factors affect overall conclusions on carbon balances of different agricultural systems. Our results show management practices that have major the most important effects on carbon balances. Overall, agricultural management with conventional tillage was found to be a net CO2 source to the atmosphere, while agricultural management under reduced tillage, low input, or organic management sequestered carbon at rates of 93, -23, -51, and -14 g CO2e m-2 yr-1, respectively for conventionally tilled, no-till, low-input, and organically managed ecosystems. Perennial systems (alfalfa and the successionnal fields) showed net carbon sequestration of -44 and -382 g CO2e m-2 yr-1, respectively. When studied systems were assumed to be used for bioenergy production, all system exhibited carbon sequestration -- between -149 and -841 g CO2e m-2 yr-1, for conventionally tilled and successionnal ecosystems, respectively.

  16. Process energy comparison for the production and harvesting of algal biomass as a biofuel feedstock.

    PubMed

    Weschler, Matthew K; Barr, William J; Harper, Willie F; Landis, Amy E

    2014-02-01

    Harvesting and drying are often described as the most energy intensive stages of microalgal biofuel production. This study analyzes two cultivation and eleven harvest technologies for the production of microalgae biomass with and without the use of drying. These technologies were combined to form 122 different production scenarios. The results of this study present a calculation methodology and optimization of total energy demand for the production of algal biomass for biofuel production. The energetic interaction between unit processes and total process energy demand are compared for each scenario. Energy requirements are shown to be highly dependent on final mass concentration, with thermal drying being the largest energy consumer. Scenarios that omit thermal drying in favor of lipid extraction from wet biomass show the most promise for energy efficient biofuel production. Scenarios which used open ponds for cultivation, followed by settling and membrane filtration were the most energy efficient. PMID:24355501

  17. Impacts of near-future cultivation of biofuel feedstocks on atmospheric composition and local air quality

    NASA Astrophysics Data System (ADS)

    Ashworth, K.; Folberth, G.; Hewitt, C. N.; Wild, O.

    2012-01-01

    Large-scale production of feedstock crops for biofuels will lead to land use changes. We quantify the effects of realistic land use change scenarios for biofuel feedstock production on isoprene emissions and hence atmospheric composition and chemistry using the HadGEM2 model. Two feedstocks are considered: oil palm for biodiesel in the tropics and short rotation coppice (SRC) in the mid-latitudes. In total, 69 Mha of oil palm and 9 Mha of SRC are planted, each sufficient to replace just over 1% of projected global fossil fuel demand in 2020. Both planting scenarios result in increases in total global annual isoprene emissions of about 1%. In each case, changes in surface concentrations of ozone and biogenic secondary organic aerosol (bSOA) are substantial at the regional scale, with implications for air quality standards. However, the changes in tropospheric burden of ozone and the OH radical, and hence effects on global climate, are negligible. Over SE Asia, one region of oil palm planting, increases in annual mean surface ozone and bSOA concentrations reach over 3 ppbv (+11%) and 0.4 μg m-3 (+10%) respectively for parts of Borneo, with monthly mean increases of up to 6.5 ppbv (+25%) and 0.5 μg m-3 (+12%). Under the SRC scenario, Europe experiences monthly mean changes of over 0.6 ppbv (+1%) and 0.1 μg m-3 (+5%) in June and July, with peak increases of over 2 ppbv (+3%) and 0.5 μg m-3 (+8 %). That appreciable regional atmospheric impacts result from low level planting scenarios demonstrates the need to include changes in emissions of reactive trace gases such as isoprene in life cycle assessments performed on potential biofuel feedstocks.

  18. Impacts of near-future cultivation of biofuel feedstocks on atmospheric composition and local air quality

    NASA Astrophysics Data System (ADS)

    Ashworth, K.; Folberth, G.; Hewitt, C. N.; Wild, O.

    2011-09-01

    Large-scale production of feedstock crops for biofuels will lead to land-use changes. We quantify the effects of realistic land use change scenarios for biofuel feedstock production on isoprene emissions and hence atmospheric composition and chemistry using the HadGEM2 model. Two feedstocks are considered: oil palm for biodiesel in the tropics and short rotation coppice (SRC) in the mid-latitudes. In total, 69 Mha of oil palm and 92 Mha of SRC are planted, each sufficient to replace just over 1 % of projected global fossil fuel demand in 2020. Both planting scenarios result in increases in total global annual isoprene emissions of about 1 %. In each case, changes in surface concentrations of ozone and biogenic secondary organic aerosol (bSOA) are significant at the regional scale and are detectable even at a global scale with implications for air quality standards. However, the changes in tropospheric burden of ozone and the OH radical, and hence effects on global climate, are negligible. The oil palm plantations and processing plants result in global average annual mean increases in ozone and bSOA of 38 pptv and 2 ng m-3 respectively. Over SE Asia, one region of planting, increases reach over 2 ppbv and 300 ng m-3 for large parts of Borneo. Planting of SRC causes global annual mean changes of 46 pptv and 3 ng m-3. Europe experiences peak monthly mean changes of almost 0.6 ppbv and 90 ng m-3 in June and July. Large areas of Central and Eastern Europe see changes of over 1.5 ppbv and 200 ng m-3 in the summer. That such significant atmospheric impacts from low level planting scenarios are discernible globally clearly demonstrates the need to include changes in emissions of reactive trace gases such as isoprene in life cycle assessments performed on potential biofuel feedstocks.

  19. Lifecycle Assessment of Biofuel Production from Wood Pyrolysis Technology

    ERIC Educational Resources Information Center

    Manyele, S. V.

    2007-01-01

    Due to a stronger dependency on biomass for energy, there is a need for improved technologies in biomass-to-energy conversion in Tanzania. This paper presents a life cycle assessment (LCA) of pyrolysis technology used for conversion of wood and wood waste to liquid biofuel. In particular, a survey of environmental impacts of the process is…

  20. BIOWINOL TECHNOLOGIES: A HYBRID GREEN PROCESS FOR BIOFUEL PRODUCTION

    EPA Science Inventory

    The ability of the unique bacteria to produce ethanol by utilizing H2 and CO2 will be determined. The project will be used to educate the community about advances and importance of bioenergy while building consumer confidence in biofuels in addressing...

  1. Lifecycle Assessment of Biofuel Production from Wood Pyrolysis Technology

    ERIC Educational Resources Information Center

    Manyele, S. V.

    2007-01-01

    Due to a stronger dependency on biomass for energy, there is a need for improved technologies in biomass-to-energy conversion in Tanzania. This paper presents a life cycle assessment (LCA) of pyrolysis technology used for conversion of wood and wood waste to liquid biofuel. In particular, a survey of environmental impacts of the process is

  2. Unraveling water quality and quantity effects of biofuels production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Developing a sustainable biofuels industry is crucial for several reasons, but what impact will it have on soil water quantity and quality? This popular press article for ISU alumni, teachers, middle/high school students and others is written to help them understand the complexity of this seemingly ...

  3. Developing herbaceous energy crops as feedstocks for biofuel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Switchgrass, giant canary reed, and alfalfa stems were evaluated as feedstocks for biochemical conversion to biofuels. The sample set consisted of field-grown samples of each of these species harvested at multiple maturities. The samples were examined for chemical composition. All the samples con...

  4. Biofuel supply chain, market, and policy analysis

    NASA Astrophysics Data System (ADS)

    Zhang, Leilei

    Renewable fuel is receiving an increasing attention as a substitute for fossil based energy. The US Department of Energy (DOE) has employed increasing effort on promoting the advanced biofuel productions. Although the advanced biofuel remains at its early stage, it is expected to play an important role in climate policy in the future in the transportation sector. This dissertation studies the emerging biofuel supply chain and markets by analyzing the production cost, and the outcomes of the biofuel market, including blended fuel market price and quantity, biofuel contract price and quantity, profitability of each stakeholder (farmers, biofuel producers, biofuel blenders) in the market. I also address government policy impacts on the emerging biofuel market. The dissertation is composed with three parts, each in a paper format. The first part studies the supply chain of emerging biofuel industry. Two optimization-based models are built to determine the number of facilities to deploy, facility locations, facility capacities, and operational planning within facilities. Cost analyses have been conducted under a variety of biofuel demand scenarios. It is my intention that this model will shed light on biofuel supply chain design considering operational planning under uncertain demand situations. The second part of the dissertation work focuses on analyzing the interaction between the key stakeholders along the supply chain. A bottom-up equilibrium model is built for the emerging biofuel market to study the competition in the advanced biofuel market, explicitly formulating the interactions between farmers, biofuel producers, blenders, and consumers. The model simulates the profit maximization of multiple market entities by incorporating their competitive decisions in farmers' land allocation, biomass transportation, biofuel production, and biofuel blending. As such, the equilibrium model is capable of and appropriate for policy analysis, especially for those policies that have complex ramifications and result in sophisticate interactions among multiple stakeholders. The third part of the dissertation investigates the impacts of flexible fuel vehicles (FFVs) market penetration levels on the market outcomes, including cellulosic biofuel production and price, blended fuel market price, and profitability of each stakeholder in the biofuel supply chain for imperfectly competitive biofuel markets. In this paper, I investigate the penetration levels of FFVs by incorporating the substitution among different fuels in blended fuel demand functions through "cross price elasticity" in a bottom-up equilibrium model framework. The complementarity based problem is solved by a Taylor expansion-based iterative procedure. At each step of the iteration, the highly nonlinear complementarity problems with constant elasticity of demand functions are linearized into linear complimentarity problems and solved until it converges. This model can be applied to investigate the interaction between the stakeholders in the biofuel market, and to assist decision making for both cellulosic biofuel investors and government.

  5. Selection, breeding and engineering of microalgae for bioenergy and biofuel production.

    PubMed

    Larkum, Anthony W D; Ross, Ian L; Kruse, Olaf; Hankamer, Ben

    2012-04-01

    Microalgal production technologies are seen as increasingly attractive for bioenergy production to improve fuel security and reduce CO(2) emissions. Photosynthetically derived fuels are a renewable, potentially carbon-neutral and scalable alternative reserve. Microalgae have particular promise because they can be produced on non-arable land and utilize saline and wastewater streams. Furthermore, emerging microalgal technologies can be used to produce a range of products such as biofuels, protein-rich animal feeds, chemical feedstocks (e.g. bioplastic precursors) and higher-value products. This review focuses on the selection, breeding and engineering of microalgae for improved biomass and biofuel conversion efficiencies. PMID:22178650

  6. The effect of biofuel production on swine farm methane and ammonia emissions.

    PubMed

    Harper, Lowry A; Flesch, Thomas K; Weaver, Kim H; Wilson, John D

    2010-01-01

    Methane (CH) and ammonia (NH3) are emitted to the atmosphere during anaerobic processing of organic matter, and both gases have detrimental environmental effects. Methane conversion to biofuel production has been suggested to reduce CH4 emissions from animal manure processing systems. The purpose of this research is to evaluate the change in CH4 and NH3 emissions in an animal feeding operation due to biofuel production from the animal manure. Gas emissions were measured from swine farms differing only in their manure-management treatment systems (conventional vs. biofuel). By removing organic matter (i.e., carbon) from the biofuel farms' manure-processing lagoons, average annual CH4 emissions were decreased by 47% compared with the conventional farm. This represents a net 44% decrease in global warming potential (CO2 equivalent) by gases emitted from the biofuel farms compared with conventional farms. However, because of the reduction of methanogenesis and its reduced effect on the chemical conversion of ammonium (NH4+) to dinitrogen (N2) gas, NH3 emissions in the biofuel farms increased by 46% over the conventional farms. These studies show that what is considered an environmentally friendly technology had mixed results and that all components of a system should be studied when making changes to existing systems. PMID:21284295

  7. Soil nutrient budgets following projected corn stover harvest for biofuel production in the conterminous United States

    USGS Publications Warehouse

    Tan, Zhengxi; Liu, Shuguang

    2015-01-01

    Increasing demand for food and biofuel feedstocks may substantially affect soil nutrient budgets, especially in the United States where there is great potential for corn (Zea mays L) stover as a biofuel feedstock. This study was designed to evaluate impacts of projected stover harvest scenarios on budgets of soil nitrogen (N), phosphorus (P), and potassium (K) currently and in the future across the conterminous United States. The required and removed N, P, and K amounts under each scenario were estimated on the basis of both their average contents in grain and stover and from an empirical model. Our analyses indicate a small depletion of soil N (−4 ± 35 kg ha−1) and K (−6 ± 36 kg ha−1) and a moderate surplus of P (37 ± 21 kg ha−1) currently on the national average, but with a noticeable variation from state to state. After harvesting both grain and projected stover, the deficits of soil N, P, and K were estimated at 114–127, 26–27, and 36–53 kg ha−1 yr−1, respectively, in 2006–2010; 131–173, 29–32, and 41–96 kg ha−1 yr−1, respectively, in 2020; and 161–207, 35–39, and 51–111 kg ha−1 yr−1, respectively, in 2050. This study indicates that the harvestable stover amount derived from the minimum stover requirement for maintaining soil organic carbon level scenarios under current fertilization rates can be sustainable for soil nutrient supply and corn production at present, but the deficit of P and K at the national scale would become larger in the future.

  8. Winter Cover Crop Biomass for Biofuel Production, Implications for Soil Coverage and Profitability

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High residue winter cover crops are critical for maximizing conservation tillage system benefits, including reductions in soil erosion, improved soil productivity, higher crop yields and greater net returns from crop production. With the increasing demand for biofuel production, the potential to har...

  9. Biofuels and biodiversity.

    PubMed

    Wiens, John; Fargione, Joseph; Hill, Jason

    2011-06-01

    The recent increase in liquid biofuel production has stemmed from a desire to reduce dependence on foreign oil, mitigate rising energy prices, promote rural economic development, and reduce greenhouse gas emissions. The growth of this industry has important implications for biodiversity, the effects of which depend largely on which biofuel feedstocks are being grown and the spatial extent and landscape pattern of land requirements for growing these feedstocks. Current biofuel production occurs largely on croplands that have long been in agricultural production. The additional land area required for future biofuels production can be met in part by reclaiming reserve or abandoned croplands and by extending cropping into lands formerly deemed marginal for agriculture. In the United States, many such marginal lands have been enrolled in the Conservation Reserve Program (CRP), providing important habitat for grassland species. The demand for corn ethanOl has changed agricultural commodity economics dramatically, already contributing to loss of CRP lands as contracts expire and lands are returned to agricultural production. Nevertheless, there are ways in which biofuels can be developed to enhance their coexistence with biodiversity. Landscape heterogeneity can be improved by interspersion of land uses, which is easier around facilities with smaller or more varied feedstock demands. The development of biofuel feedstocks that yield high net energy returns with minimal carbon debts or that do not require additional land for production, such as residues and wastes, should be encouraged. Competing land uses, including both biofuel production and biodiversity protection, should be subjected to comprehensive cost-benefit analysis, so that incentives can be directed where they will do the most good. PMID:21774415

  10. Determining the global maximum biofuel production potential without conflicting with food and feed consumption

    NASA Astrophysics Data System (ADS)

    Pumkaew, Watcharapol

    This study tries to resolve the competition between food and biofuel by balancing the allocation between food and feed areas and biofuel areas for the entire world. The maximum energy production is calculated by determining the theoretical amount of energy that can be grown, once food and feed consumption is taken into account, based on the assumption that unprotected grass and woody lands and forest lands can be converted into cultivated lands. The total optimum land area for biofuel energy, 4,926.49 Mha, consists of corn, rapeseed, sugar beet, sugar cane, and grasses. When considering energy conversion efficiency, the maximum energy production is 520.5 EJ. Of this amount, 5.9 EJ can be identified with food and feed energy and 514.6 EJ can be identified with biofuel energy. This result is a theoretical value to illustrate the potential global land area for biofuel. The biofuel energy production per area of land in this study is calculated to be 0.12 EJ/Mha. With regards to the limitation in the degree of invasion by grass and woody land and forest land areas, if it is not more than 10 percent, the biofuel energy production can serve about 76 percent of energy demand for transportation in 2009. The total optimum land area is about 45 percent of global cultivated land area. Sensitivity analysis shows that the land area of corn, sweet sorghum, sugarcane, grass, and woody crops is sensitive to energy content. The land area of sweet sorghum and soybeans is sensitive to the land area for food and feed consumption. Also, the land area of corn, sugar beet, and sugarcane is sensitive to the potential crop land area. This study, done at the global level, can also apply in a local area by using local constraints.

  11. Biofuels from Pyrolysis: Catalytic Biocrude Production in a Novel, Short-Contact Time Reactor

    SciTech Connect

    2010-01-01

    Broad Funding Opportunity Announcement Project: RTI is developing a new pyrolysis process to convert second-generation biomass into biofuels in one simple step. Pyrolysis is the decomposition of substances by heating—the same process used to render wood into charcoal, caramelize sugar, and dry roast coffee and beans. RTI’s catalytic biomass pyrolysis differs from conventional flash pyrolysis in that its end product contains less oxygen, metals, and nitrogen—all of which contribute to corrosion, instability, and inefficiency in the fuel-production process. This technology is expected to easily integrate into the existing domestic petroleum refining infrastructure, making it an economically attractive option for biofuels production.

  12. Catalytic oxidation of biorefinery lignin to value-added chemicals to support sustainable biofuel production.

    PubMed

    Ma, Ruoshui; Xu, Yan; Zhang, Xiao

    2015-01-01

    Transforming plant biomass to biofuel is one of the few solutions that can truly sustain mankind's long-term needs for liquid transportation fuel with minimized environmental impact. However, despite decades of effort, commercial development of biomass-to-biofuel conversion processes is still not an economically viable proposition. Identifying value-added co-products along with the production of biofuel provides a key solution to overcoming this economic barrier. Lignin is the second most abundant component next to cellulose in almost all plant biomass; the emerging biomass refinery industry will inevitably generate an enormous amount of lignin. Development of selective biorefinery lignin-to-bioproducts conversion processes will play a pivotal role in significantly improving the economic feasibility and sustainability of biofuel production from renewable biomass. The urgency and importance of this endeavor has been increasingly recognized in the last few years. This paper reviews state-of-the-art oxidative lignin depolymerization chemistries employed in the papermaking process and oxidative catalysts that can be applied to biorefinery lignin to produce platform chemicals including phenolic compounds, dicarboxylic acids, and quinones in high selectivity and yield. The potential synergies of integrating new catalysts with commercial delignification chemistries are discussed. We hope the information will build on the existing body of knowledge to provide new insights towards developing practical and commercially viable lignin conversion technologies, enabling sustainable biofuel production from lignocellulosic biomass to be competitive with fossil fuel. PMID:25272962

  13. Engineering cyanobacteria for direct biofuel production from CO2.

    PubMed

    Savakis, Philipp; Hellingwerf, Klaas J

    2015-06-01

    For a sustainable future of our society it is essential to close the global carbon cycle. Oxidised forms of carbon, in particular CO2, can be used to synthesise energy-rich organic molecules. Engineered cyanobacteria have attracted attention as catalysts for the direct conversion of CO2 into reduced fuel compounds. Proof of principle for this approach has been provided for a vast range of commodity chemicals, mostly energy carriers, such as short chain and medium chain alcohols. More recently, research has focused on the photosynthetic production of compounds with higher added value, most notably terpenoids. Below we review the recent developments that have improved the state-of-the-art of this approach and speculate on future developments. PMID:25305544

  14. Carbon Calculator for Land Use Change from Biofuels Production (CCLUB). Users' Manual and Technical Documentation

    SciTech Connect

    Dunn, Jennifer B.; Qin, Zhangcai; Mueller, Steffen; Kwon, Ho-young; Wander, Michelle M.; Wang, Michael

    2014-09-01

    The Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) calculates carbon emissions from land use change (LUC) for four different ethanol production pathways including corn grain ethanol and cellulosic ethanol from corn stover, Miscanthus, and switchgrass. This document discusses the version of CCLUB released September 30, 2014 which includes corn and three cellulosic feedstocks: corn stover, Miscanthus, and switchgrass.

  15. The National Biofuels Strategy - Importance of sustainable feedstock production systems in regional-based supply chains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Region-based production systems are needed to produce the feedstocks that will be turned into the biofuels required to meet Federal mandated targets. Executive and Legislative actions have put into motion significant government responses designed to advance the development and production of domestic...

  16. Biogeochemical research priorities for sustainable biofuel and bioenergy feedstock production in the Americas

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rapid expansion in biomass production for biofuels and bioenergy in the Americas is increasing demands on the ecosystem resources required to sustain soil and site productivity. We review the current state of knowledge and highlight gaps in research on biogeochemical processes and ecosystem sustaina...

  17. Performance assessment of biofuel production in an algae-based remediation system.

    PubMed

    Wuang, Shy Chyi; Luo, Yanpei Darren; Wang, Simai; Chua, Pei Qiang Danny; Tee, Pok Siang

    2016-03-10

    The production of biofuel from microalgae has been an area of great interest as microalgae have higher productivities than land plants, and certain species have high lipid constituents which are the major feedstock for biodiesel production. One way to enhance the economic feasibility of algal-based biofuel is to couple it with waste remediation. This study investigated the technical feasibility of cultivating Chlorella sp. and Nannochloropsis sp. with fish water for biofuel production. The remediation potential of Chlorella sp. was found to be higher but the lipid yield is lower, when compared to Nannochloropsis sp. Lipid productivities were found to be similar for both types of algae at 1.1-1.3mgL(-1)h(-1). The fatty acid profiles of the obtained lipids were found suitable for biofuel production, and the calorific values were high at 30-32MJ/kg. The results provide insights into lipid production in Chlorella sp. and Nannochloropsis sp., when coupled with waste remediation. PMID:26808868

  18. Heterologous Expression of Plant Cell Wall Degrading Enzymes for Effective Production of Cellulosic Biofuels

    PubMed Central

    Jung, Sang-Kyu; Parisutham, Vinuselvi; Jeong, Seong Hun; Lee, Sung Kuk

    2012-01-01

    A major technical challenge in the cost-effective production of cellulosic biofuel is the need to lower the cost of plant cell wall degrading enzymes (PCDE), which is required for the production of sugars from biomass. Several competitive, low-cost technologies have been developed to produce PCDE in different host organisms such as Escherichia coli, Zymomonas mobilis, and plant. Selection of an ideal host organism is very important, because each host organism has its own unique features. Synthetic biology-aided tools enable heterologous expression of PCDE in recombinant E. coli or Z. mobilis and allow successful consolidated bioprocessing (CBP) in these microorganisms. In-planta expression provides an opportunity to simplify the process of enzyme production and plant biomass processing and leads to self-deconstruction of plant cell walls. Although the future of currently available technologies is difficult to predict, a complete and viable platform will most likely be available through the integration of the existing approaches with the development of breakthrough technologies. PMID:22911272

  19. Application of orange peel waste in the production of solid biofuels and biosorbents.

    PubMed

    Santos, Carolina Monteiro; Dweck, Jo; Viotto, Renata Silva; Rosa, André Henrique; de Morais, Leandro Cardoso

    2015-11-01

    This work aimed to study the potential use of pyrolyzed orange peels as solid biofuels and biosorption of heavy metals. The dry biomass and the biofuel showed moderate levels of carbon (44-62%), high levels of oxygen (30-47%), lower levels of hydrogen (3-6%), nitrogen (1-2.6%), sulfur (0.4-0.8%) and ash with a maximum of 7.8%. The activation energy was calculated using Kissinger method, involving a 3 step process: volatilization of water, biomass degradation and volatilization of the degradation products. The calorific value obtained was 19.3MJ/kg. The studies of metal biosorption based on the Langmuir model obtained the best possible data fits. The results obtained in this work indicated that the potential use of waste orange peel as a biosorbent and as a solid biofuel are feasible, this product could be used in industrial processes, favoring the world economy. PMID:26280099

  20. Microalgae to biofuels: life cycle impacts of methane production of anaerobically digested lipid extracted algae.

    PubMed

    Quinn, Jason C; Hanif, Asma; Sharvelle, Sybil; Bradley, Thomas H

    2014-11-01

    This study presents experimental measurements of the biochemical methane production for whole and lipid extracted Nannochloropsis salina. Results show whole microalgae produced 430 cm(3)-CH4 g-volatile solids(-1) (g-VS) (?=60), 3 times more methane than was produced by the LEA, 140 cm(3)-CH4 g-VS(-1) (?=30). Results illustrate current anaerobic modeling efforts in microalgae to biofuel assessments are not reflecting the impact of lipid removal. On a systems level, the overestimation of methane production is shown to positively skew the environmental impact of the microalgae to biofuels process. Discussion focuses on a comparison results to those of previous anaerobic digestion studies and quantifies the corresponding change in greenhouse gas emissions of the microalgae to biofuels process based on results from this study. PMID:25181698

  1. Mathematical modeling of unicellular microalgae and cyanobacteria metabolism for biofuel production.

    PubMed

    Baroukh, Caroline; Muñoz-Tamayo, Rafael; Bernard, Olivier; Steyer, Jean-Philippe

    2015-06-01

    The conversion of microalgae lipids and cyanobacteria carbohydrates into biofuels appears to be a promising source of renewable energy. This requires a thorough understanding of their carbon metabolism, supported by mathematical models, in order to optimize biofuel production. However, unlike heterotrophic microorganisms that utilize the same substrate as sources of energy and carbon, photoautotrophic microorganisms require light for energy and CO2 as carbon source. Furthermore, they are submitted to permanent fluctuating light environments due to outdoor cultivation or mixing inducing a flashing effect. Although, modeling these nonstandard organisms is a major challenge for which classical tools are often inadequate, this step remains a prerequisite towards efficient optimization of outdoor biofuel production at an industrial scale. PMID:25827115

  2. Future prospects for production of methanol and hydrogen from biomass

    NASA Astrophysics Data System (ADS)

    Hamelinck, Carlo N.; Faaij, André P. C.

    Technical and economic prospects of the future production of methanol and hydrogen from biomass have been evaluated. A technology review, including promising future components, was made, resulting in a set of promising conversion concepts. Flowsheeting models were made to analyse the technical performance. Results were used for economic evaluations. Overall energy efficiencies are around 55% HHV for methanol and around 60% for hydrogen production. Accounting for the lower energy quality of fuel compared to electricity, once-through concepts perform better than the concepts aimed for fuel only production. Hot gas cleaning can contribute to a better performance. Systems of 400 MW th input produce biofuels at US 8-12/GJ, this is above the current gasoline production price of US 4-6/GJ. This cost price is largely dictated by the capital investments. The outcomes for the various system types are rather comparable, although concepts focussing on optimised fuel production with little or no electricity co-production perform somewhat better. Hydrogen concepts using ceramic membranes perform well due to their higher overall efficiency combined with modest investment. Long-term (2020) cost reductions reside in cheaper biomass, technological learning, and application of large scales up to 2000 MW th. This could bring the production costs of biofuels in the US$ 5-7/GJ range. Biomass-derived methanol and hydrogen are likely to become competitive fuels tomorrow.

  3. Process modeling and supply chain design for advanced biofuel production based on bio-oil gasification

    NASA Astrophysics Data System (ADS)

    Li, Qi

    As a potential substitute for petroleum-based fuel, second generation biofuels are playing an increasingly important role due to their economic, environmental, and social benefits. With the rapid development of biofuel industry, there has been an increasing literature on the techno-economic analysis and supply chain design for biofuel production based on a variety of production pathways. A recently proposed production pathway of advanced biofuel is to convert biomass to bio-oil at widely distributed small-scale fast pyrolysis plants, then gasify the bio-oil to syngas and upgrade the syngas to transportation fuels in centralized biorefinery. This thesis aims to investigate two types of assessments on this bio-oil gasification pathway: techno-economic analysis based on process modeling and literature data; supply chain design with a focus on optimal decisions for number of facilities to build, facility capacities and logistic decisions considering uncertainties. A detailed process modeling with corn stover as feedstock and liquid fuels as the final products is presented. Techno-economic analysis of the bio-oil gasification pathway is also discussed to assess the economic feasibility. Some preliminary results show a capital investment of 438 million dollar and minimum fuel selling price (MSP) of $5.6 per gallon of gasoline equivalent. The sensitivity analysis finds that MSP is most sensitive to internal rate of return (IRR), biomass feedstock cost, and fixed capital cost. A two-stage stochastic programming is formulated to solve the supply chain design problem considering uncertainties in biomass availability, technology advancement, and biofuel price. The first-stage makes the capital investment decisions including the locations and capacities of the decentralized fast pyrolysis plants and the centralized biorefinery while the second-stage determines the biomass and biofuel flows. The numerical results and case study illustrate that considering uncertainties can be pivotal in this supply chain design and optimization problem. Also, farmers' participation has a significant effect on the decision making process.

  4. Microbial conversion of pyrolytic products to biofuels: a novel and sustainable approach toward second-generation biofuels.

    PubMed

    Islam, Zia Ul; Zhisheng, Yu; Hassan, El Barbary; Dongdong, Chang; Hongxun, Zhang

    2015-12-01

    This review highlights the potential of the pyrolysis-based biofuels production, bio-ethanol in particular, and lipid in general as an alternative and sustainable solution for the rising environmental concerns and rapidly depleting natural fuel resources. Levoglucosan (1,6-anhydrous-β-D-glucopyranose) is the major anhydrosugar compound resulting from the degradation of cellulose during the fast pyrolysis process of biomass and thus the most attractive fermentation substrate in the bio-oil. The challenges for pyrolysis-based biorefineries are the inefficient detoxification strategies, and the lack of naturally available efficient and suitable fermentation organisms that could ferment the levoglucosan directly into bio-ethanol. In case of indirect fermentation, acid hydrolysis is used to convert levoglucosan into glucose and subsequently to ethanol and lipids via fermentation biocatalysts, however the presence of fermentation inhibitors poses a big hurdle to successful fermentation relative to pure glucose. Among the detoxification strategies studied so far, over-liming, extraction with solvents like (n-butanol, ethyl acetate), and activated carbon seem very promising, but still further research is required for the optimization of existing detoxification strategies as well as developing new ones. In order to make the pyrolysis-based biofuel production a more efficient as well as cost-effective process, direct fermentation of pyrolysis oil-associated fermentable sugars, especially levoglucosan is highlly desirable. This can be achieved either by expanding the search to identify naturally available direct levoglusoan utilizers or modify the existing fermentation biocatalysts (yeasts and bacteria) with direct levoglucosan pathway coupled with tolerance engineering could significantly improve the overall performance of these microorganisms. PMID:26433384

  5. Designer synthetic media for studying microbial-catalyzed biofuel production

    SciTech Connect

    Tang, Xiaoyu; da Costa Sousa, Leonardo; Jin, Mingjie; Chundawat, Shishir; Chambliss, Charles; Lau, Ming W; Xiao, Zeyi; Dale, Bruce E; Balan, Venkatesh

    2015-01-01

    Background: The fermentation inhibition of yeast or bacteria by lignocellulose-derived degradation products, during hexose/pentose co-fermentation, is a major bottleneck for cost-effective lignocellulosic biorefineries. To engineer microbial strains for improved performance, it is critical to understand the mechanisms of inhibition that affect fermentative organisms in the presence of major components of a lignocellulosic hydrolysate. The development of a synthetic lignocellulosic hydrolysate (SH) media with a composition similar to the actual biomass hydrolysate will be an important advancement to facilitate these studies. In this work, we characterized the nutrients and plant-derived decomposition products present in AFEX™ pretreated corn stover hydrolysate (ACH). The SH was formulated based on the ACH composition and was further used to evaluate the inhibitory effects of various families of decomposition products during Saccharomyces cerevisiae 424A (LNH-ST) fermentation. Results: The ACH contained high levels of nitrogenous compounds, notably amides, pyrazines, and imidazoles. In contrast, a relatively low content of furans and aromatic and aliphatic acids were found in the ACH. Though most of the families of decomposition products were inhibitory to xylose fermentation, due to their abundance, the nitrogenous compounds showed the most inhibition. From these compounds, amides (products of the ammonolysis reaction) contributed the most to the reduction of the fermentation performance. However, this result is associated to a concentration effect, as the corresponding carboxylic acids (products of hydrolysis) promoted greater inhibition when present at the same molar concentration as the amides. Due to its complexity, the formulated SH did not perfectly match the fermentation profile of the actual hydrolysate, especially the growth curve. However, the SH formulation was effective for studying the inhibitory effect of various compounds on yeast fermentation. Conclusions: The formulation of SHs is an important advancement for future multi-omics studies and for better understanding the mechanisms of fermentation inhibition in lignocellulosic hydrolysates. The SH formulated in this work was instrumental for defining the most important inhibitors in the ACH. Major AFEX decomposition products are less inhibitory to yeast fermentation than the products of dilute acid or steam explosion pretreatments; thus, ACH is readily fermentable by yeast without any detoxification.

  6. Designer synthetic media for studying microbial-catalyzed biofuel production

    DOE PAGESBeta

    Tang, Xiaoyu; da Costa Sousa, Leonardo; Jin, Mingjie; Chundawat, Shishir; Chambliss, Charles; Lau, Ming W; Xiao, Zeyi; Dale, Bruce E; Balan, Venkatesh

    2015-01-01

    Background: The fermentation inhibition of yeast or bacteria by lignocellulose-derived degradation products, during hexose/pentose co-fermentation, is a major bottleneck for cost-effective lignocellulosic biorefineries. To engineer microbial strains for improved performance, it is critical to understand the mechanisms of inhibition that affect fermentative organisms in the presence of major components of a lignocellulosic hydrolysate. The development of a synthetic lignocellulosic hydrolysate (SH) media with a composition similar to the actual biomass hydrolysate will be an important advancement to facilitate these studies. In this work, we characterized the nutrients and plant-derived decomposition products present in AFEX™ pretreated corn stover hydrolysate (ACH). Themore » SH was formulated based on the ACH composition and was further used to evaluate the inhibitory effects of various families of decomposition products during Saccharomyces cerevisiae 424A (LNH-ST) fermentation. Results: The ACH contained high levels of nitrogenous compounds, notably amides, pyrazines, and imidazoles. In contrast, a relatively low content of furans and aromatic and aliphatic acids were found in the ACH. Though most of the families of decomposition products were inhibitory to xylose fermentation, due to their abundance, the nitrogenous compounds showed the most inhibition. From these compounds, amides (products of the ammonolysis reaction) contributed the most to the reduction of the fermentation performance. However, this result is associated to a concentration effect, as the corresponding carboxylic acids (products of hydrolysis) promoted greater inhibition when present at the same molar concentration as the amides. Due to its complexity, the formulated SH did not perfectly match the fermentation profile of the actual hydrolysate, especially the growth curve. However, the SH formulation was effective for studying the inhibitory effect of various compounds on yeast fermentation. Conclusions: The formulation of SHs is an important advancement for future multi-omics studies and for better understanding the mechanisms of fermentation inhibition in lignocellulosic hydrolysates. The SH formulated in this work was instrumental for defining the most important inhibitors in the ACH. Major AFEX decomposition products are less inhibitory to yeast fermentation than the products of dilute acid or steam explosion pretreatments; thus, ACH is readily fermentable by yeast without any detoxification.« less

  7. Simulating and evaluating best management practices for integrated landscape management scenarios in biofuel feedstock production

    SciTech Connect

    Ha, Miae; Wu, May

    2015-09-08

    Sound crop and land management strategies can maintain land productivity and improve the environmental sustainability of agricultural crop and feedstock production. With this study, it evaluates a strategy of incorporating landscape design and management concepts into bioenergy feedstock production. It examines the effect of land conversion and agricultural best management practices (BMPs) on water quality (nutrients and suspended sediments) and hydrology. The strategy was applied to the watershed of the South Fork Iowa River in Iowa, where the focus was on converting low-productivity land to provide cellulosic biomass and implementing riparian buffers. The Soil and Water Assessment Tool (SWAT) was employed to simulate the impact at watershed and sub-basin scales. The study compared the representation of buffers by using trapping efficiency and area ratio methods in SWAT. Landscape design and management scenarios were developed to quantify water quality under (i) current land use, (ii) partial land conversion to switchgrass, and (iii) riparian buffer implementation. Results show that implementation of vegetative barriers and riparian buffer can trap the loss of total nitrogen, total phosphorus, and sediment significantly. The effect increases with the increase of buffer area coverage. Implementing riparian buffer at 30 m width is able to produce 4 million liters of biofuels. When low-productivity land (15.2% of total watershed land area) is converted to grow switchgrass, suspended sediment, total nitrogen, total phosphorus, and nitrate loadings are reduced by 69.3%, 55.5%, 46.1%, and 13.4%, respectively. The results highlight the significant role of lower-productivity land and buffers in cellulosic biomass and provide insights into the design of an integrated landscape with a conservation buffer for future bioenergy feedstock production.

  8. Simulating and evaluating best management practices for integrated landscape management scenarios in biofuel feedstock production

    DOE PAGESBeta

    Ha, Miae; Wu, May

    2015-09-08

    Sound crop and land management strategies can maintain land productivity and improve the environmental sustainability of agricultural crop and feedstock production. With this study, it evaluates a strategy of incorporating landscape design and management concepts into bioenergy feedstock production. It examines the effect of land conversion and agricultural best management practices (BMPs) on water quality (nutrients and suspended sediments) and hydrology. The strategy was applied to the watershed of the South Fork Iowa River in Iowa, where the focus was on converting low-productivity land to provide cellulosic biomass and implementing riparian buffers. The Soil and Water Assessment Tool (SWAT) wasmore » employed to simulate the impact at watershed and sub-basin scales. The study compared the representation of buffers by using trapping efficiency and area ratio methods in SWAT. Landscape design and management scenarios were developed to quantify water quality under (i) current land use, (ii) partial land conversion to switchgrass, and (iii) riparian buffer implementation. Results show that implementation of vegetative barriers and riparian buffer can trap the loss of total nitrogen, total phosphorus, and sediment significantly. The effect increases with the increase of buffer area coverage. Implementing riparian buffer at 30 m width is able to produce 4 million liters of biofuels. When low-productivity land (15.2% of total watershed land area) is converted to grow switchgrass, suspended sediment, total nitrogen, total phosphorus, and nitrate loadings are reduced by 69.3%, 55.5%, 46.1%, and 13.4%, respectively. The results highlight the significant role of lower-productivity land and buffers in cellulosic biomass and provide insights into the design of an integrated landscape with a conservation buffer for future bioenergy feedstock production.« less

  9. Modeling Regional Groundwater Implications of Biofuel Crop Production in the Great Lakes Region

    NASA Astrophysics Data System (ADS)

    Parish, A.; Kendall, A. D.; Basso, B.; Hyndman, D. W.

    2013-12-01

    In response to a growing call for renewable sources of energy that do not compete directly with food resources, the use of second-generation 'cellulosic' biofuel feedstocks has gained much attention in recent years. The push to advance the technologies that would make such a transformation possible is motivated by the United States Renewable Fuel Standard mandate to produce 36 billion gallons of biofuels by 2022, an increase of 334 percent from 2009. Many different crops, including maize, miscanthus, switchgrass, and poplar have shown promise as cellulosic feedstocks, and in an attempt to supply the needed biomass to meet the 2022 mandate, production of these crops have been on the rise. Yet little is known about the sustainability of large-scale conversion of land to cellulosic biofuel crop production; more research is needed to understand the effects that these crops will have on the quality and quantity of groundwater. This study presents a model scale-up approach to address three questions: What are the hydrologic and nutrient demands of the primary biofuel crops? Which biofuel crops are more water efficient in terms of demand verses energy produced? What are the types and availabilities of land to expand production of these biofuel crops? To answer these questions, we apply a point-based crop dynamics model in combination with a regional-scale hydrologic model, parameterized using stream discharge and chemistry data collected from two representative watersheds in Wisconsin. Approximately 17 stream sites in each watershed are selected for data collection for model parameterization, including stream discharge, nutrient concentrations, and basic chemical characteristics. We then use the System Approach to Land Use Sustainability (SALUS) model, which predicts crop growth under varying soil and climate conditions, to drive vegetation dynamics and groundwater transport of nutrients within the Integrated Landscape Hydrology Model (ILHM). ILHM predictions of stream discharge and baseflow delivery of nutrients are then compared to field data to validate model predictions.

  10. Using mobile distributed pyrolysis facilities to deliver a forest residue resource for bio-fuel production

    NASA Astrophysics Data System (ADS)

    Brown, Duncan

    Distributed mobile conversion facilities using either fast pyrolysis or torrefaction processes can be used to convert forest residues to more energy dense substances (bio-oil, bio-slurry or torrefied wood) that can be transported as feedstock for bio-fuel facilities. All feedstock are suited for gasification, which produces syngas that can be used to synthesise petrol or diesel via Fischer-Tropsch reactions, or produce hydrogen via water gas shift reactions. Alternatively, the bio-oil product of fast pyrolysis may be upgraded to produce petrol and diesel, or can undergo steam reformation to produce hydrogen. Implementing a network of mobile facilities reduces the energy content of forest residues delivered to a bio-fuel facility as mobile facilities use a fraction of the biomass energy content to meet thermal or electrical demands. The total energy delivered by bio-oil, bio-slurry and torrefied wood is 45%, 65% and 87% of the initial forest residue energy content, respectively. However, implementing mobile facilities is economically feasible when large transport distances are required. For an annual harvest of 1.717 million m3 (equivalent to 2000 ODTPD), transport costs are reduced to less than 40% of the total levelised delivered feedstock cost when mobile facilities are implemented; transport costs account for up to 80% of feedstock costs for conventional woodchip delivery. Torrefaction provides the lowest cost pathway of delivering a forest residue resource when using mobile facilities. Cost savings occur against woodchip delivery for annual forest residue harvests above 2.25 million m3 or when transport distances greater than 250 km are required. Important parameters that influence levelised delivered costs of feedstock are transport distances (forest residue spatial density), haul cost factors, thermal and electrical demands of mobile facilities, and initial moisture content of forest residues. Relocating mobile facilities can be optimised for lowest cost delivery as transport distances of raw biomass are reduced. The overall cost of bio-fuel production is determined by the feedstock delivery pathway and also the bio-fuel production process employed. Results show that the minimum cost of petrol and diesel production is 0.86 litre -1 when a bio-oil feedstock is upgraded. This corresponds to a 2750 TPD upgrading facility requiring an annual harvest of 4.30 million m3. The miniμm cost of hydrogen production is 2.92 kg -1, via the gasification of a woodchip feedstock and subsequent water gas shift reactions. This corresponds to a 1100 ODTPD facility and requires an annual harvest of 947,000 m3. The levelised cost of bio-fuel strongly depends on the size of annual harvest required for bio-fuel facilities. There are optimal harvest volumes (bio-fuel facility sizes) for each bio-fuel production route, which yield minimum bio-fuel production costs. These occur as the benefits of economies of scale for larger bio-fuel facilities compete against increasing transport costs for larger harvests. Optimal harvest volumes are larger for bio-fuel production routes that use feedstock sourced from mobile facilities, as mobile facilities reduce total transport requirements.

  11. Sources of biomass feedstock variability and the potential impact on biofuels production

    DOE PAGESBeta

    Williams, C. Luke; Westover, Tyler L.; Emerson, Rachel M.; Tumuluru, Jaya Shankar; Li, Chenlin

    2015-11-23

    In this study, terrestrial lignocellulosic biomass has the potential to be a carbon neutral and domestic source of fuels and chemicals. However, the innate variability of biomass resources, such as herbaceous and woody materials, and the inconsistency within a single resource due to disparate growth and harvesting conditions, presents challenges for downstream processes which often require materials that are physically and chemically consistent. Intrinsic biomass characteristics, including moisture content, carbohydrate and ash compositions, bulk density, and particle size/shape distributions are highly variable and can impact the economics of transforming biomass into value-added products. For instance, ash content increases by anmore » order of magnitude between woody and herbaceous feedstocks (from ~0.5 to 5 %, respectively) while lignin content drops by a factor of two (from ~30 to 15 %, respectively). This increase in ash and reduction in lignin leads to biofuel conversion consequences, such as reduced pyrolysis oil yields for herbaceous products as compared to woody material. In this review, the sources of variability for key biomass characteristics are presented for multiple types of biomass. Additionally, this review investigates the major impacts of the variability in biomass composition on four conversion processes: fermentation, hydrothermal liquefaction, pyrolysis, and direct combustion. Finally, future research processes aimed at reducing the detrimental impacts of biomass variability on conversion to fuels and chemicals are proposed.« less

  12. Sources of biomass feedstock variability and the potential impact on biofuels production

    SciTech Connect

    Williams, C. Luke; Westover, Tyler L.; Emerson, Rachel M.; Tumuluru, Jaya Shankar; Li, Chenlin

    2015-11-23

    In this study, terrestrial lignocellulosic biomass has the potential to be a carbon neutral and domestic source of fuels and chemicals. However, the innate variability of biomass resources, such as herbaceous and woody materials, and the inconsistency within a single resource due to disparate growth and harvesting conditions, presents challenges for downstream processes which often require materials that are physically and chemically consistent. Intrinsic biomass characteristics, including moisture content, carbohydrate and ash compositions, bulk density, and particle size/shape distributions are highly variable and can impact the economics of transforming biomass into value-added products. For instance, ash content increases by an order of magnitude between woody and herbaceous feedstocks (from ~0.5 to 5 %, respectively) while lignin content drops by a factor of two (from ~30 to 15 %, respectively). This increase in ash and reduction in lignin leads to biofuel conversion consequences, such as reduced pyrolysis oil yields for herbaceous products as compared to woody material. In this review, the sources of variability for key biomass characteristics are presented for multiple types of biomass. Additionally, this review investigates the major impacts of the variability in biomass composition on four conversion processes: fermentation, hydrothermal liquefaction, pyrolysis, and direct combustion. Finally, future research processes aimed at reducing the detrimental impacts of biomass variability on conversion to fuels and chemicals are proposed.

  13. Biofuel production and climate mitigation potential from marginal lands in US North Central region

    NASA Astrophysics Data System (ADS)

    Gelfand, I.; Sahajpal, R.; Zhang, X.; Izaurralde, R. C.; Robertson, G. P.

    2010-12-01

    An ever-increasing demand for liquid fuels, amidst concerns of anthropogenic impacts on the environment and fossil fuels availability, has spurred a strong interest in the development of agriculturally-based renewable energy sources. However, increasing demand for food as well as direct and indirect effects on land use, have raised concerns about reliance on grain-based ethanol and shifted research towards the direction of cellulosic feedstocks. In order to understand the future possibility for using agricultural systems for bio-fuel production, we present here a full greenhouse gas (GHG) balance of six potential sources of cellulosic feedstocks production. From 1991 to 2008, we measured GHGs sinks and sources in cropped and nearby unmanaged ecosystems in SW Michigan. The measurements included soil fluxes of GHGs (N2O and CH4), soil organic carbon concentration change, agronomic practices data, and biomass yields. We analyzed two types of intensively managed annual cropping systems under corn-soybean-wheat rotation (conventional tillage and no till), two perennial systems (alfalfa and poplar plantation), and one successional system. The use of agricultural residues for biofuel feedstock from conventionally-tilled crops had the lowest climate stabilization potential (-9 ±13 gCO2e m-2 y-1). In contrast, biomass collected from a successional system fertilized with N at123 kg ha-1y-1 showed the highest climate stabilization potential (-749 ±30 gCO2e m-2 y-1). We used our results to parameterize the EPIC model, which, together with GIS analysis was used to scale up the biomass productivity of the best environmentally performing systems to the marginal lands of the 10-state U.S. North Central region. Assuming 80 km as the maximum distance for road haulage to the biorefinery from the field, we identified 32 potential biorefinery placements each capable of supplying sufficient feedstock to produce at least 133 × 106 L y-1. In total, ethanol production from marginal lands could produce ~29 × 109 L ethanol y-1, or about 48% of the 2007 U.S. Congress legislative mandate.

  14. Plant triacylglycerols as feedstocks for the production of biofuels.

    PubMed

    Durrett, Timothy P; Benning, Christoph; Ohlrogge, John

    2008-05-01

    Triacylglycerols produced by plants are one of the most energy-rich and abundant forms of reduced carbon available from nature. Given their chemical similarities, plant oils represent a logical substitute for conventional diesel, a non-renewable energy source. However, as plant oils are too viscous for use in modern diesel engines, they are converted to fatty acid esters. The resulting fuel is commonly referred to as biodiesel, and offers many advantages over conventional diesel. Chief among these is that biodiesel is derived from renewable sources. In addition, the production and subsequent consumption of biodiesel results in less greenhouse gas emission compared to conventional diesel. However, the widespread adoption of biodiesel faces a number of challenges. The biggest of these is a limited supply of biodiesel feedstocks. Thus, plant oil production needs to be greatly increased for biodiesel to replace a major proportion of the current and future fuel needs of the world. An increased understanding of how plants synthesize fatty acids and triacylglycerols will ultimately allow the development of novel energy crops. For example, knowledge of the regulation of oil synthesis has suggested ways to produce triacylglycerols in abundant non-seed tissues. Additionally, biodiesel has poor cold-temperature performance and low oxidative stability. Improving the fuel characteristics of biodiesel can be achieved by altering the fatty acid composition. In this regard, the generation of transgenic soybean lines with high oleic acid content represents one way in which plant biotechnology has already contributed to the improvement of biodiesel. PMID:18476866

  15. 75 FR 42745 - Production Incentives for Cellulosic Biofuels: Notice of Program Intent

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-22

    ..., ``Production Incentives for Cellulosic Biofuels; Reverse Auction Procedures and Standards,'' (74 FR 52867... Office of Biomass Program, in the Office of Energy Efficiency and Renewable Energy, intends to conduct a... directed to: Mr. Neil Rossmeissl, Office of the Biomass Program, U.S. Department of Energy, Mailstop...

  16. Fluid Fertilizer's Role in Sustainng Soils Used for Bio-Fuels Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The short- and long-term effects on soil nutrient cycling, physical properties, and biological activity of striving for higher grain yields and removing crop residues for bio-fuels production must be understood to provide more quantitative crop and soil management guidelines. Studies focusing on til...

  17. Establishment of perennial grass species for cellulosic biofuel production in Georgia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In order for biofuels to become a viable alternative energy source in the state of Georgia, appropriate feed stocks must be developed to supply this burgeoning industry. Georgia is optimum for biomass production because of its warm subtropical climate, large number of growing degree days, and an es...

  18. Industrial-strength ecology: trade-offs and opportunities in algal biofuel production.

    PubMed

    Shurin, Jonathan B; Abbott, Rachel L; Deal, Michael S; Kwan, Garfield T; Litchman, Elena; McBride, Robert C; Mandal, Shovon; Smith, Val H

    2013-11-01

    Microalgae represent one of the most promising groups of candidate organisms for replacing fossil fuels with contemporary primary production as a renewable source of energy. Algae can produce many times more biomass per unit area than terrestrial crop plants, easing the competing demands for land with food crops and native ecosystems. However, several aspects of algal biology present unique challenges to the industrial-scale aquaculture of photosynthetic microorganisms. These include high susceptibility to invading aquatic consumers and weeds, as well as prodigious requirements for nutrients that may compete with the fertiliser demands of other crops. Most research on algal biofuel technologies approaches these problems from a cellular or genetic perspective, attempting either to engineer or select algal strains with particular traits. However, inherent functional trade-offs may limit the capacity of genetic selection or synthetic biology to simultaneously optimise multiple functional traits for biofuel productivity and resilience. We argue that a community engineering approach that manages microalgal diversity, species composition and environmental conditions may lead to more robust and productive biofuel ecosystems. We review evidence for trade-offs, challenges and opportunities in algal biofuel cultivation with a goal of guiding research towards intensifying bioenergy production using established principles of community and ecosystem ecology. PMID:24015819

  19. Fluid Fertilizer's Role in Sustaining Soils Used for Bio-fuels Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The short- and long-term effects on soil nutrient cycling, physical properties, and biological activity of striving for higher grain yields and removing crop residues for bio-fuels production must be understood to provide more quantitative crop and soil management guidelines. This study focuses prim...

  20. Moving toward energy security and sustainability in 2050 by reconfiguring biofuel production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To achieve energy security and sustainability by 2050 requires reconfiguring biofuel production both by building on current infrastructure and existing technology and also by making substantial improvements and changes in the feedstocks used, the process technologies applied, and the fuels produced....

  1. Fluid Fertilizer’s Role in Sustaining Soils Used for Bio-fuel Feedstock Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The short- and long-term effects on soil nutrient cycling, physical properties, and biological activity of striving for higher grain yields and removing crop residues for bio-fuels production must be understood to provide more quantitative crop and soil management guidelines. This study focuses on p...

  2. Producing sorghum cellulosic feedstock for advanced biofuels production and its impact on soil physical properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    According Energy Policy Act of 2005, the U.S. must produce 21 billion gallons of advanced biofuels in 2022. Cellulosic material is considered a renewable and environmental improved alternative source for energy production. Sorghum (Sorghum bicolor L.) is considered a high cellulosic biomass producti...

  3. Satellite-based assessment of water requirement for biofuel feedstock production in Maui, Hawaii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water availability is one of the limiting factors for sustainable production of biofuel crops. A common method for determining crop water requirement is to multiply daily potential evapotranspiration (ETo) calculated from meteorological parameters by a crop coefficient (Kc) to obtain actual crop eva...

  4. Switchgrass Production in Washington – Part II of Biofuel Feedstocks in Washington

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Integrated Cropping Systems group at Prosser, WA made up of WSU and USDA-ARS personnel have been evaluating production aspects of a number of irrigated biofuel crops that can be planted in rotation with high value vegetables: oilseeds for biodiesel (safflower, soybeans, mustard, canola/rapeseed...

  5. Tradeoffs and synergies between biofuel production and large-scale solar infrastructure in deserts

    NASA Astrophysics Data System (ADS)

    Ravi, S.; Lobell, D. B.; Field, C. B.

    2012-12-01

    Solar energy installations in deserts are on the rise, fueled by technological advances and policy changes. Deserts, with a combination of high solar radiation and availability of large areas unusable for crop production are ideal locations for large scale solar installations. For efficient power generation, solar infrastructures require large amounts of water for operation (mostly for cleaning panels and dust suppression), leading to significant moisture additions to desert soil. A pertinent question is how to use the moisture inputs for sustainable agriculture/biofuel production. We investigated the water requirements for large solar infrastructures in North American deserts and explored the possibilities for integrating biofuel production with solar infrastructure. In co-located systems the possible decline in yields due to shading by solar panels may be offsetted by the benefits of periodic water addition to biofuel crops, simpler dust management and more efficient power generation in solar installations, and decreased impacts on natural habitats and scarce resources in deserts. In particular, we evaluated the potential to integrate solar infrastructure with biomass feedstocks that grow in arid and semi-arid lands (Agave Spp), which are found to produce high yields with minimal water inputs. To this end, we conducted detailed life cycle analysis for these coupled agave biofuel - solar energy systems to explore the tradeoffs and synergies, in the context of energy input-output, water use and carbon emissions.

  6. An integrated modeling framework for exploring flow regime and water quality changes with increasing biofuel crop production in the U.S. Corn Belt

    NASA Astrophysics Data System (ADS)

    Yaeger, Mary A.; Housh, Mashor; Cai, Ximing; Sivapalan, Murugesu

    2014-12-01

    To better address the dynamic interactions between human and hydrologic systems, we develop an integrated modeling framework that employs a System of Systems optimization model to emulate human development decisions which are then incorporated into a watershed model to estimate the resulting hydrologic impacts. The two models are run interactively to simulate the coevolution of coupled human-nature systems, such that reciprocal feedbacks between hydrologic processes and human decisions (i.e., human impacts on critical low flows and hydrologic impacts on human decisions on land and water use) can be assessed. The framework is applied to a Midwestern U.S. agricultural watershed, in the context of proposed biofuels development. This operation is illustrated by projecting three possible future coevolution trajectories, two of which use dedicated biofuel crops to reduce annual watershed nitrate export while meeting ethanol production targets. Imposition of a primary external driver (biofuel mandate) combined with different secondary drivers (water quality targets) results in highly nonlinear and multiscale responses of both the human and hydrologic systems, including multiple tradeoffs, impacting the future coevolution of the system in complex, heterogeneous ways. The strength of the hydrologic response is sensitive to the magnitude of the secondary driver; 45% nitrate reduction target leads to noticeable impacts at the outlet, while a 30% reduction leads to noticeable impacts that are mainly local. The local responses are conditioned by previous human-hydrologic modifications and their spatial relationship to the new biofuel development, highlighting the importance of past coevolutionary history in predicting future trajectories of change.

  7. Chaotropicity: a key factor in product tolerance of biofuel-producing microorganisms.

    PubMed

    Cray, Jonathan A; Stevenson, Andrew; Ball, Philip; Bankar, Sandip B; Eleutherio, Elis C A; Ezeji, Thaddeus C; Singhal, Rekha S; Thevelein, Johan M; Timson, David J; Hallsworth, John E

    2015-06-01

    Fermentation products can chaotropically disorder macromolecular systems and induce oxidative stress, thus inhibiting biofuel production. Recently, the chaotropic activities of ethanol, butanol and vanillin have been quantified (5.93, 37.4, 174kJ kg(-1)m(-1) respectively). Use of low temperatures and/or stabilizing (kosmotropic) substances, and other approaches, can reduce, neutralize or circumvent product-chaotropicity. However, there may be limits to the alcohol concentrations that cells can tolerate; e.g. for ethanol tolerance in the most robust Saccharomyces cerevisiae strains, these are close to both the solubility limit (<25%, w/v ethanol) and the water-activity limit of the most xerotolerant strains (0.880). Nevertheless, knowledge-based strategies to mitigate or neutralize chaotropicity could lead to major improvements in rates of product formation and yields, and also therefore in the economics of biofuel production. PMID:25841213

  8. Economic evaluation of technology for a new generation biofuel production using wastes.

    PubMed

    Koutinas, Athanasios; Kanellaki, Maria; Bekatorou, Argyro; Kandylis, Panagiotis; Pissaridi, Katerina; Dima, Agapi; Boura, Konstantina; Lappa, Katerina; Tsafrakidou, Panagiota; Stergiou, Panagiota-Yiolanda; Foukis, Athanasios; Gkini, Olga A; Papamichael, Emmanuel M

    2016-01-01

    An economic evaluation of an integrated technology for industrial scale new generation biofuel production using whey, vinasse, and lignocellulosic biomass as raw materials is reported. Anaerobic packed-bed bioreactors were used for organic acids production using initially synthetic media and then wastes. Butyric, lactic and acetic acid were predominately produced from vinasse, whey, and cellulose, respectively. Mass balance was calculated for a 16,000L daily production capacity. Liquid-liquid extraction was applied for recovery of the organic acids using butanol-1 as an effective extraction solvent which serves also as the alcohol for the subsequent enzyme-catalyzed esterification. The investment needed for the installation of the factory was estimated to about 1.7million€ with depreciation excepted at about 3months. For cellulosics, the installation investment was estimated to be about 7-fold higher with depreciation at about 1.5years. The proposed technology is an alternative trend in biofuel production. PMID:26492169

  9. Identification and microbial production of a terpene-based advanced biofuel

    PubMed Central

    Peralta-Yahya, Pamela P.; Ouellet, Mario; Chan, Rossana; Mukhopadhyay, Aindrila; Keasling, Jay D.; Lee, Taek Soon

    2011-01-01

    Rising petroleum costs, trade imbalances and environmental concerns have stimulated efforts to advance the microbial production of fuels from lignocellulosic biomass. Here we identify a novel biosynthetic alternative to D2 diesel fuel, bisabolane, and engineer microbial platforms for the production of its immediate precursor, bisabolene. First, we identify bisabolane as an alternative to D2 diesel by measuring the fuel properties of chemically hydrogenated commercial bisabolene. Then, via a combination of enzyme screening and metabolic engineering, we obtain a more than tenfold increase in bisabolene titers in Escherichia coli to >900 mg l−1. We produce bisabolene in Saccharomyces cerevisiae (>900 mg l−1), a widely used platform for the production of ethanol. Finally, we chemically hydrogenate biosynthetic bisabolene into bisabolane. This work presents a framework for the identification of novel terpene-based advanced biofuels and the rapid engineering of microbial farnesyl diphosphate-overproducing platforms for the production of biofuels. PMID:21952217

  10. Environmental, economic and social impact of aviation biofuel production in Brazil.

    PubMed

    Cremonez, Paulo Andr; Feroldi, Michael; de Jesus de Oliveira, Carlos; Teleken, Joel Gustavo; Alves, Helton Jos; Sampaio, Silvio Czar

    2015-03-25

    The Brazilian aviation industry is currently developing biofuel technologies that can maintain the operational and energy demands of the sector, while reducing the dependence on fossil fuels (mainly kerosene) and greenhouse gas emissions. The aim of the current research was to identify the major environmental, economic and social impacts arising from the production of aviation biofuels in Brazil. Despite the great potential of these fuels, there is a significant need for improved routes of production and specifically for lower production costs of these materials. In addition, the productive chains of raw materials for obtaining these bioenergetics can be linked to environmental impacts by NOx emissions, extensive use of agricultural land, loss of wildlife and intensive water use, as well as economic, social and political impacts. PMID:25582405

  11. A High-Resolution National Microalgae Biofuel Production and Resource Assessment

    NASA Astrophysics Data System (ADS)

    Wigmosta, M.; Coleman, A.; Skaggs, R.; Venteris, E.

    2012-12-01

    Microalgae are receiving increased global attention as a potential sustainable "energy crop" for biofuel production. An important step to realizing the potential of algae is quantifying the demands commercial-scale algal biofuel production will place on available resources. We present a high-resolution national-scale spatiotemporal assessment that begins to answer fundamental questions of where sustainable production can occur, what types and quantities of water, land, and nutrients are required, and how much energy is produced. A series of coupled model components were developed at a high spatiotemporal scale on the basis of the dominant biophysical processes affecting algal growth. Land suitable for open pond microalgae production consisting of 1200 acres per unit farm is identified using a multi-criteria land suitability model. Physics-based biomass growth and pond temperature models are then are used with location-specific meteorological and topographic data at 89,756 suitable unit farms to estimate 30-years of hourly biofuel production, nutrient requirements, and multi-source consumptive water demand. These resource requirements are compared with available resource supply and transport constraints to prioritize potential locations for sustainable microalgae feedstock production and evaluate the associated tradeoffs between production, resources, and economics.

  12. Chromatin landscaping in algae reveals novel regulation pathway for biofuels production

    SciTech Connect

    Ngan, Chew Yee; Wong, Chee-Hong; Choi, Cindy; Pratap, Abhishek; Han, James; Wei, Chia-Lin

    2013-02-19

    The diminishing reserve of fossil fuels calls for the development of biofuels. Biofuels are produced from renewable resources, including photosynthetic organisms, generating clean energy. Microalgae is one of the potential feedstock for biofuels production. It grows easily even in waste water, and poses no competition to agricultural crops for arable land. However, little is known about the algae lipid biosynthetic regulatory mechanisms. Most studies relied on the homology to other plant model organisms, in particular Arabidopsis or through low coverage expression analysis to identify key enzymes. This limits the discovery of new components in the biosynthetic pathways, particularly the genetic regulators and effort to maximize the production efficiency of algal biofuels. Here we report an unprecedented and de novo approach to dissect the algal lipid pathways through disclosing the temporal regulations of chromatin states during lipid biosynthesis. We have generated genome wide chromatin maps in chlamydomonas genome using ChIP-seq targeting 7 histone modifications and RNA polymerase II in a time-series manner throughout conditions activating lipid biosynthesis. To our surprise, the combinatory profiles of histone codes uncovered new regulatory mechanism in gene expression in algae. Coupled with matched RNA-seq data, chromatin changes revealed potential novel regulators and candidate genes involved in the activation of lipid accumulations. Genetic perturbation on these candidate regulators further demonstrated the potential to manipulate the regulatory cascade for lipid synthesis efficiency. Exploring epigenetic landscape in microalgae shown here provides powerful tools needed in improving biofuel production and new technology platform for renewable energy generation, global carbon management, and environmental survey.

  13. Scope of algae as third generation biofuels.

    PubMed

    Behera, Shuvashish; Singh, Richa; Arora, Richa; Sharma, Nilesh Kumar; Shukla, Madhulika; Kumar, Sachin

    2014-01-01

    An initiative has been taken to develop different solid, liquid, and gaseous biofuels as the alternative energy resources. The current research and technology based on the third generation biofuels derived from algal biomass have been considered as the best alternative bioresource that avoids the disadvantages of first and second generation biofuels. Algal biomass has been investigated for the implementation of economic conversion processes producing different biofuels such as biodiesel, bioethanol, biogas, biohydrogen, and other valuable co-products. In the present review, the recent findings and advance developments in algal biomass for improved biofuel production have been explored. This review discusses about the importance of the algal cell contents, various strategies for product formation through various conversion technologies, and its future scope as an energy security. PMID:25717470

  14. Scope of Algae as Third Generation Biofuels

    PubMed Central

    Behera, Shuvashish; Singh, Richa; Arora, Richa; Sharma, Nilesh Kumar; Shukla, Madhulika; Kumar, Sachin

    2015-01-01

    An initiative has been taken to develop different solid, liquid, and gaseous biofuels as the alternative energy resources. The current research and technology based on the third generation biofuels derived from algal biomass have been considered as the best alternative bioresource that avoids the disadvantages of first and second generation biofuels. Algal biomass has been investigated for the implementation of economic conversion processes producing different biofuels such as biodiesel, bioethanol, biogas, biohydrogen, and other valuable co-products. In the present review, the recent findings and advance developments in algal biomass for improved biofuel production have been explored. This review discusses about the importance of the algal cell contents, various strategies for product formation through various conversion technologies, and its future scope as an energy security. PMID:25717470

  15. The current potential of algae biofuels in the United Arab Emirates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In spite of future uncertainties about industrial algae biofuel production, the UAE is planning to become "a world leader in biofuels from the algae industry by 2020;" thus joining major countries which have already started producing renewable energy and biofuels (biodiesel and bioethanol) from rene...

  16. Algae as a Feedstock for Transportation Fuels. The Future of Biofuels?

    SciTech Connect

    McGill, Ralph

    2008-05-15

    Events in world energy markets over the past several years have prompted many new technical developments as well as political support for alternative transportation fuels, especially those that are renewable. We have seen dramatic rises in the demand for and production of fuel ethanol from sugar cane and corn and biodiesel from vegetable oils. The quantities of these fuels being used continue to rise dramatically, and their use is helping to create a political climate for doing even more. But, the quantities are still far too small to stem the tide of rising crude prices worldwide. In fact, the use of some traditional crops (corn, sugar, soy, etc.) in making fuels instead of food is apparently beginning to impact the cost of food worldwide. Thus, there is considerable interest in developing alternative biofuel feedstocks for use in making fuels -- feedstocks that are not used in the food industries. Of course, we know that there is a lot of work in developing cellulosic-based ethanol that would be made from woody biomass. Process development is the critical path for this option, and the breakthrough in reducing the cost of the process has been elusive thus far. Making biodiesel from vegetable oils is a well-developed and inexpensive process, but to date there have been few reasonable alternatives for making biodiesel, although advanced processes such as gasification of biomass remain an option.

  17. Algal biofuels.

    PubMed

    Razeghifard, Reza

    2013-11-01

    The world is facing energy crisis and environmental issues due to the depletion of fossil fuels and increasing CO2 concentration in the atmosphere. Growing microalgae can contribute to practical solutions for these global problems because they can harvest solar energy and capture CO2 by converting it into biofuel using photosynthesis. Microalgae are robust organisms capable of rapid growth under a variety of conditions including in open ponds or closed photobioreactors. Their reduced biomass compounds can be used as the feedstock for mass production of a variety of biofuels. As another advantage, their ability to accumulate or secrete biofuels can be controlled by changing their growth conditions or metabolic engineering. This review is aimed to highlight different forms of biofuels produced by microalgae and the approaches taken to improve their biofuel productivity. The costs for industrial-scale production of algal biofuels in open ponds or closed photobioreactors are analyzed. Different strategies for photoproduction of hydrogen by the hydrogenase enzyme of green algae are discussed. Algae are also good sources of biodiesel since some species can make large quantities of lipids as their biomass. The lipid contents for some of the best oil-producing strains of algae in optimized growth conditions are reviewed. The potential of microalgae for producing petroleum related chemicals or ready-make fuels such as bioethanol, triterpenic hydrocarbons, isobutyraldehyde, isobutanol, and isoprene from their biomass are also presented. PMID:23605290

  18. High productivity cultivation of a heat-resistant microalga Chlorella sorokiniana for biofuel production.

    PubMed

    Li, Tingting; Zheng, Yubin; Yu, Liang; Chen, Shulin

    2013-03-01

    To augment biomass and lipid productivities of heterotrophic cultured microalgae Chlorella sorokiniana, the influence of environmental temperature and medium factors, such as carbon source, nitrogen source, and their initial concentrations was investigated in this study. The microalga C. sorokiniana could tolerate up to 42°C and showed the highest growth rate of 1.60d(-1) at 37°C. The maximum dry cell weight (DCW) and corresponding lipid concentration was obtained with 80gL(-1) of initial glucose and 4gL(-1) of initial KNO3 at 37°C. In 5-L batch fermentation, the DCW increased dramatically from 0.9gL(-1) to 37.6gL(-1) in the first 72h cultivation, with the DCW productivity of 12.2gL(-1)d(-1). The maximum lipid content of 31.5% was achieved in 96h and the lipid productivity was 2.9gL(-1)d(-1). The results showed C. sorokiniana could be a promising strain for biofuel production. PMID:23340103

  19. Quantitative uncertainty analysis of Life Cycle Assessment for algal biofuel production.

    PubMed

    Sills, Deborah L; Paramita, Vidia; Franke, Michael J; Johnson, Michael C; Akabas, Tal M; Greene, Charles H; Tester, Jefferson W

    2013-01-15

    As a result of algae's promise as a renewable energy feedstock, numerous studies have used Life Cycle Assessment (LCA) to quantify the environmental performance of algal biofuels, yet there is no consensus of results among them. Our work, motivated by the lack of comprehensive uncertainty analysis in previous studies, uses a Monte Carlo approach to estimate ranges of expected values of LCA metrics by incorporating parameter variability with empirically specified distribution functions. Results show that large uncertainties exist at virtually all steps of the biofuel production process. Although our findings agree with a number of earlier studies on matters such as the need for wet lipid extraction, nutrients recovered from waste streams, and high energy coproducts, the ranges of reported LCA metrics show that uncertainty analysis is crucial for developing technologies, such as algal biofuels. In addition, the ranges of energy return on (energy) invested (EROI) values resulting from our analysis help explain the high variability in EROI values from earlier studies. Reporting results from LCA models as ranges, and not single values, will more reliably inform industry and policy makers on expected energetic and environmental performance of biofuels produced from microalgae. PMID:23237457

  20. Organisms for biofuel production: natural bioresources and methodologies for improving their biosynthetic potentials.

    PubMed

    Hu, Guangrong; Ji, Shiqi; Yu, Yanchong; Wang, Shi'an; Zhou, Gongke; Li, Fuli

    2015-01-01

    In order to relieve the pressure of energy supply and environment contamination that humans are facing, there are now intensive worldwide efforts to explore natural bioresources for production of energy storage compounds, such as lipids, alcohols, hydrocarbons, and polysaccharides. Around the world, many plants have been evaluated and developed as feedstock for bioenergy production, among which several crops have successfully achieved industrialization. Microalgae are another group of photosynthetic autotroph of interest due to their superior growth rates, relatively high photosynthetic conversion efficiencies, and vast metabolic capabilities. Heterotrophic microorganisms, such as yeast and bacteria, can utilize carbohydrates from lignocellulosic biomass directly or after pretreatment and enzymatic hydrolysis to produce liquid biofuels such as ethanol and butanol. Although finding a suitable organism for biofuel production is not easy, many naturally occurring organisms with good traits have recently been obtained. This review mainly focuses on the new organism resources discovered in the last 5 years for production of transport fuels (biodiesel, gasoline, jet fuel, and alkanes) and hydrogen, and available methods to improve natural organisms as platforms for the production of biofuels. PMID:24085385

  1. Interactions of woody biofuel feedstock production systems with water resources: Considerations for sustainability.

    SciTech Connect

    Trettin, Carl,C.; Amatya, Devendra; Coleman, Mark.

    2008-07-01

    Abstract. Water resources are important for the production of woody biofuel feedstocks. It is necessary to ensure that production systems do not adversely affect the quantity or quality of surface and ground water. The effects of woody biomass plantations on water resources are largely dependent on the prior land use and the management regime. Experience from both irrigated and non-irrigated systems has demonstrated that woody biofuel production systems do not impair water quality. Water quality actually improves from conversion of idle or degraded agricultural lands to woody biomass plantations. Site water balance may be altered by cultivation of woody biomass plantations relative to agricultural use, due to increases in evapostranspiration (ET) and storage. Incorporation of woody biomass production plantations within the landscape provides an opportunity to improve the quality of runoff water and soil conservation. Given the centrality of water resources to the sustainability of ecosystem services and other values derived, the experience with woody biofuels feedstock production systems is positive. Keywords. Short rotation woody crop, forest hydrology, water quality, hardwood plantation.

  2. Biofuel, dairy production and beef in Brazil: competing claims on land use in São Paulo state.

    PubMed

    Novo, André Luiz Monteiro; Jansen, Kees; Slingerland, Maja; Giller, Ken

    2010-01-01

    This paper examines the competing claims on land use resulting from the expansion of biofuel production. Sugarcane for biofuel drives agrarian change in So Paulo state, which has become the major ethanol-producing region in Brazil. We analyse how the expansion of sugarcane-based ethanol in So Paulo state has impacted dairy and beef production. Historical changes in land use, production technologies, and product and land prices are described, as well as how these are linked to changing policies in Brazil. We argue that sugarcane/biofuel expansion should be understood in the context of the dynamics of other agricultural sectors and the long-term national political economy rather than as solely due to recent global demand for biofuel. This argument is based on a meticulous analysis of changes in three important sectors - sugarcane, dairy farming, and beef production - and the mutual interactions between these sectors. PMID:21125724

  3. Genetic resources for advanced biofuel production described with the Gene Ontology

    PubMed Central

    Torto-Alalibo, Trudy; Purwantini, Endang; Lomax, Jane; Setubal, João C.; Mukhopadhyay, Biswarup; Tyler, Brett M.

    2014-01-01

    Dramatic increases in research in the area of microbial biofuel production coupled with high-throughput data generation on bioenergy-related microbes has led to a deluge of information in the scientific literature and in databases. Consolidating this information and making it easily accessible requires a unified vocabulary. The Gene Ontology (GO) fulfills that requirement, as it is a well-developed structured vocabulary that describes the activities and locations of gene products in a consistent manner across all kingdoms of life. The Microbial ENergy processes Gene Ontology () project is extending the GO to include new terms to describe microbial processes of interest to bioenergy production. Our effort has added over 600 bioenergy related terms to the Gene Ontology. These terms will aid in the comprehensive annotation of gene products from diverse energy-related microbial genomes. An area of microbial energy research that has received a lot of attention is microbial production of advanced biofuels. These include alcohols such as butanol, isopropanol, isobutanol, and fuels derived from fatty acids, isoprenoids, and polyhydroxyalkanoates. These fuels are superior to first generation biofuels (ethanol and biodiesel esterified from vegetable oil or animal fat), can be generated from non-food feedstock sources, can be used as supplements or substitutes for gasoline, diesel and jet fuels, and can be stored and distributed using existing infrastructure. Here we review the roles of genes associated with synthesis of advanced biofuels, and at the same time introduce the use of the GO to describe the functions of these genes in a standardized way. PMID:25346727

  4. Genetic resources for advanced biofuel production described with the Gene Ontology.

    PubMed

    Torto-Alalibo, Trudy; Purwantini, Endang; Lomax, Jane; Setubal, João C; Mukhopadhyay, Biswarup; Tyler, Brett M

    2014-01-01

    Dramatic increases in research in the area of microbial biofuel production coupled with high-throughput data generation on bioenergy-related microbes has led to a deluge of information in the scientific literature and in databases. Consolidating this information and making it easily accessible requires a unified vocabulary. The Gene Ontology (GO) fulfills that requirement, as it is a well-developed structured vocabulary that describes the activities and locations of gene products in a consistent manner across all kingdoms of life. The Microbial ENergy processes Gene Ontology () project is extending the GO to include new terms to describe microbial processes of interest to bioenergy production. Our effort has added over 600 bioenergy related terms to the Gene Ontology. These terms will aid in the comprehensive annotation of gene products from diverse energy-related microbial genomes. An area of microbial energy research that has received a lot of attention is microbial production of advanced biofuels. These include alcohols such as butanol, isopropanol, isobutanol, and fuels derived from fatty acids, isoprenoids, and polyhydroxyalkanoates. These fuels are superior to first generation biofuels (ethanol and biodiesel esterified from vegetable oil or animal fat), can be generated from non-food feedstock sources, can be used as supplements or substitutes for gasoline, diesel and jet fuels, and can be stored and distributed using existing infrastructure. Here we review the roles of genes associated with synthesis of advanced biofuels, and at the same time introduce the use of the GO to describe the functions of these genes in a standardized way. PMID:25346727

  5. Genetic resources for advanced biofuel production described with the Gene Ontology

    DOE PAGESBeta

    Torto-Alalibo, Trudy; Purwantini, Endang; Lomax, Jane; Setubal, Joao C.; Mukhopadhyay, Biswarup; Tyler, Brett M.

    2014-10-10

    Dramatic increases in research in the area of microbial biofuel production coupled with high-throughput data generation on bioenergy-related microbes has led to a deluge of information in the scientific literature and in databases. Consolidating this information and making it easily accessible requires a unified vocabulary.The Gene Ontology (GO) fulfills that requirement, as it is a well-developed structured vocabulary that describes the activities and locations of gene products in a consistent manner across all kingdoms of life. The Microbial ENergy processes Gene Ontology (http://www.mengo.biochem.vt.edu) project is extending the GO to include new terms to describe microbial processes of interest to bioenergymore » production. Our effort has added over 600 bioenergy related terms to the Gene Ontology. These terms will aid in the comprehensive annotation of gene products from diverse energy-related microbial genomes. An area of microbial energy research that has received a lot of attention is microbial production of advanced biofuels. These include alcohols such as butanol, isopropanol, isobutanol, and fuels derived from fatty acids, isoprenoids, and polyhydroxyalkanoates. These fuels are superior to first generation biofuels (ethanol and biodiesel esterified from vegetable oil or animal fat), can be generated from non-food feedstock sources, can be used as supplements or substitutes for gasoline, diesel and jet fuels, and can be stored and distributed using existing infrastructure. We review the roles of genes associated with synthesis of advanced biofuels, and at the same time introduce the use of the GO to describe the functions of these genes in a standardized way.« less

  6. Genetic resources for advanced biofuel production described with the Gene Ontology

    SciTech Connect

    Torto-Alalibo, Trudy; Purwantini, Endang; Lomax, Jane; Setubal, Joao C.; Mukhopadhyay, Biswarup; Tyler, Brett M.

    2014-10-10

    Dramatic increases in research in the area of microbial biofuel production coupled with high-throughput data generation on bioenergy-related microbes has led to a deluge of information in the scientific literature and in databases. Consolidating this information and making it easily accessible requires a unified vocabulary.The Gene Ontology (GO) fulfills that requirement, as it is a well-developed structured vocabulary that describes the activities and locations of gene products in a consistent manner across all kingdoms of life. The Microbial ENergy processes Gene Ontology (http://www.mengo.biochem.vt.edu) project is extending the GO to include new terms to describe microbial processes of interest to bioenergy production. Our effort has added over 600 bioenergy related terms to the Gene Ontology. These terms will aid in the comprehensive annotation of gene products from diverse energy-related microbial genomes. An area of microbial energy research that has received a lot of attention is microbial production of advanced biofuels. These include alcohols such as butanol, isopropanol, isobutanol, and fuels derived from fatty acids, isoprenoids, and polyhydroxyalkanoates. These fuels are superior to first generation biofuels (ethanol and biodiesel esterified from vegetable oil or animal fat), can be generated from non-food feedstock sources, can be used as supplements or substitutes for gasoline, diesel and jet fuels, and can be stored and distributed using existing infrastructure. We review the roles of genes associated with synthesis of advanced biofuels, and at the same time introduce the use of the GO to describe the functions of these genes in a standardized way.

  7. Predicting the adsorption of second generation biofuels by polymeric resins with applications for in situ product recovery (ISPR).

    PubMed

    Nielsen, David R; Amarasiriwardena, Gihan S; Prather, Kristala L J

    2010-04-01

    The application of hydrophobic polymeric resins as solid-phase adsorbent materials for the recovery and purification of prospective second generation biofuel compounds, including ethanol, iso-propanol, n-propanol, iso-butanol, n-butanol, 2-methyl-1-butanol, 3-methyl-1-butanol, and n-pentanol, has been investigated. A simple, yet robust correlation has been proposed to model the relative equilibrium partitioning behavior of a series of branched and n-alcohols as a function of their relative hydrophobicity, and has been applied to ultimately predict their adsorption potential. The proposed model adequately predicts the adsorption behavior of the entire series of alcohols studied, as well as with six different adsorbent phases composed of three different polymer matrices. Those resins with a non-polar monomeric structure and high specific surface area provided the highest overall adsorption of each of the studied compounds. Meanwhile, longer chain alcohols were subject to greater adsorption due to their increasingly hydrophobic nature. Among the tested series of alcohols, five-carbon isomers displayed the greatest potential for economical recovery in future, multiphase bioprocess designs. The present study provides the first demonstration of the ability of hydrophobic polymer resins to serve as effective in situ product recovery (ISPR) devices for the production of second generation biofuels. PMID:20044248

  8. Monster potential meets potential monster: pros and cons of deploying genetically modified microalgae for biofuels production

    PubMed Central

    Flynn, K. J.; Mitra, A.; Greenwell, H. C.; Sui, J.

    2013-01-01

    Biofuels production from microalgae attracts much attention but remains an unproven technology. We explore routes to enhance production through modifications to a range of generic microalgal physiological characteristics. Our analysis shows that biofuels production may be enhanced ca fivefold through genetic modification (GM) of factors affecting growth rate, respiration, photoacclimation, photosynthesis efficiency and the minimum cell quotas for nitrogen and phosphorous (N : C and P : C). However, simulations indicate that the ideal GM microalgae for commercial deployment could, on escape to the environment, become a harmful algal bloom species par excellence, with attendant risks to ecosystems and livelihoods. In large measure, this is because an organism able to produce carbohydrate and/or lipid at high rates, providing stock metabolites for biofuels production, will also be able to attain a stoichiometric composition that will be far from optimal as food for the support of zooplankton growth. This composition could suppress or even halt the grazing activity that would otherwise control the microalgal growth in nature. In consequence, we recommend that the genetic manipulation of microalgae, with inherent consequences on a scale comparable to geoengineering, should be considered under strict international regulation. PMID:24427510

  9. Monster potential meets potential monster: pros and cons of deploying genetically modified microalgae for biofuels production.

    PubMed

    Flynn, K J; Mitra, A; Greenwell, H C; Sui, J

    2013-02-01

    Biofuels production from microalgae attracts much attention but remains an unproven technology. We explore routes to enhance production through modifications to a range of generic microalgal physiological characteristics. Our analysis shows that biofuels production may be enhanced ca fivefold through genetic modification (GM) of factors affecting growth rate, respiration, photoacclimation, photosynthesis efficiency and the minimum cell quotas for nitrogen and phosphorous (N : C and P : C). However, simulations indicate that the ideal GM microalgae for commercial deployment could, on escape to the environment, become a harmful algal bloom species par excellence, with attendant risks to ecosystems and livelihoods. In large measure, this is because an organism able to produce carbohydrate and/or lipid at high rates, providing stock metabolites for biofuels production, will also be able to attain a stoichiometric composition that will be far from optimal as food for the support of zooplankton growth. This composition could suppress or even halt the grazing activity that would otherwise control the microalgal growth in nature. In consequence, we recommend that the genetic manipulation of microalgae, with inherent consequences on a scale comparable to geoengineering, should be considered under strict international regulation. PMID:24427510

  10. Bioelectrochemical reduction of volatile fatty acids in anaerobic digestion effluent for the production of biofuels.

    PubMed

    Kondaveeti, Sanath; Min, Booki

    2015-12-15

    This study proves for the first time the feasibility of biofuel production from anaerobic digestion effluent via bioelectrochemical cell operation at various applied cell voltages (1.0, 1.5 and 2.0 V). An increase in cell voltage from 1 to 2 V resulted in more reduction current generation (-0.48 to -0.78 mA) at a lowered cathode potential (-0.45 to -0.84 mV vs Ag/AgCl). Various alcohols were produced depending on applied cell voltages, and the main products were butanol, ethanol, and propanol. Hydrogen and methane production were also observed in the headspace of the cell. A large amount of lactic acid was unexpectedly formed at all conditions, which might be the primary cause of the limited biofuel production. The addition of neutral red (NR) to the system could increase the cathodic reduction current, and thus more biofuels were produced with an enhanced alcohol formation compared to without a mediator. PMID:26402877

  11. Importance of systems biology in engineering microbes for biofuel production

    SciTech Connect

    Mukhopadhyay, Aindrila; Redding, Alyssa M.; Rutherford, Becky J.; Keasling, Jay D.

    2009-12-02

    Microorganisms have been rich sources for natural products, some of which have found use as fuels, commodity chemicals, specialty chemicals, polymers, and drugs, to name a few. The recent interest in production of transportation fuels from renewable resources has catalyzed numerous research endeavors that focus on developing microbial systems for production of such natural products. Eliminating bottlenecks in microbial metabolic pathways and alleviating the stresses due to production of these chemicals are crucial in the generation of robust and efficient production hosts. The use of systems-level studies makes it possible to comprehensively understand the impact of pathway engineering within the context of the entire host metabolism, to diagnose stresses due to product synthesis, and provides the rationale to cost-effectively engineer optimal industrial microorganisms.

  12. Biofuels Issues and Trends

    EIA Publications

    2012-01-01

    This report presents data on biofuels consumption, production, imports and exports, including data collected by others than the U.S. Energy Information Administration. It also discusses important developments in biofuels markets.

  13. From fields to fuels: recent advances in the microbial production of biofuels.

    PubMed

    Kung, Yan; Runguphan, Weerawat; Keasling, Jay D

    2012-11-16

    Amid grave concerns over global climate change and with increasingly strained access to fossil fuels, the synthetic biology community has stepped up to the challenge of developing microbial platforms for the production of advanced biofuels. The adoption of gasoline, diesel, and jet fuel alternatives derived from microbial sources has the potential to significantly limit net greenhouse gas emissions. In this effort, great strides have been made in recent years toward the engineering of microorganisms to produce transportation fuels derived from alcohol, fatty acid, and isoprenoid biosynthesis. We provide an overview of the biosynthetic pathways devised in the strain development of biofuel-producing microorganisms. We also highlight many of the commonly used and newly devised engineering strategies that have been employed to identify and overcome pathway bottlenecks and problems of toxicity to maximize production titers. PMID:23656227

  14. Microbial advanced biofuels production: overcoming emulsification challenges for large-scale operation.

    PubMed

    Heeres, Arjan S; Picone, Carolina S F; van der Wielen, Luuk A M; Cunha, Rosiane L; Cuellar, Maria C

    2014-04-01

    Isoprenoids and alkanes produced and secreted by microorganisms are emerging as an alternative biofuel for diesel and jet fuel replacements. In a similar way as for other bioprocesses comprising an organic liquid phase, the presence of microorganisms, medium composition, and process conditions may result in emulsion formation during fermentation, hindering product recovery. At the same time, a low-cost production process overcoming this challenge is required to make these advanced biofuels a feasible alternative. We review the main mechanisms and causes of emulsion formation during fermentation, because a better understanding on the microscale can give insights into how to improve large-scale processes and the process technology options that can address these challenges. PMID:24630476

  15. The challenge of enzyme cost in the production of lignocellulosic biofuels.

    PubMed

    Klein-Marcuschamer, Daniel; Oleskowicz-Popiel, Piotr; Simmons, Blake A; Blanch, Harvey W

    2012-04-01

    With the aim of understanding the contribution of enzymes to the cost of lignocellulosic biofuels, we constructed a techno-economic model for the production of fungal cellulases. We found that the cost of producing enzymes was much higher than that commonly assumed in the literature. For example, the cost contribution of enzymes to ethanol produced by the conversion of corn stover was found to be $0.68/gal if the sugars in the biomass could be converted at maximum theoretical yields, and $1.47/gal if the yields were based on saccharification and fermentation yields that have been previously reported in the scientific literature. We performed a sensitivity analysis to study the effect of feedstock prices and fermentation times on the cost contribution of enzymes to ethanol price. We conclude that a significant effort is still required to lower the contribution of enzymes to biofuel production costs. PMID:22095526

  16. Fatty Aldehydes in Cyanobacteria Are a Metabolically Flexible Precursor for a Diversity of Biofuel Products

    PubMed Central

    Kaiser, Brett K.; Carleton, Michael; Hickman, Jason W.; Miller, Cameron; Lawson, David; Budde, Mark; Warrener, Paul; Paredes, Angel; Mullapudi, Srinivas; Navarro, Patricia; Cross, Fred; Roberts, James M.

    2013-01-01

    We describe how pathway engineering can be used to convert a single intermediate derived from lipid biosynthesis, fatty aldehydes, into a variety of biofuel precursors including alkanes, free fatty acids and wax esters. In cyanobacteria, long-chain acyl-ACPs can be reduced to fatty aldehydes, and then decarbonylated to alkanes. We discovered a cyanobacteria class-3 aldehyde-dehydrogenase, AldE, that was necessary and sufficient to instead oxidize fatty aldehyde precursors into fatty acids. Overexpression of enzymes in this pathway resulted in production of 50 to 100 fold more fatty acids than alkanes, and the fatty acids were secreted from the cell. Co-expression of acyl-ACP reductase, an alcohol-dehydrogenase and a wax-ester-synthase resulted in a third fate for fatty aldehydes: conversion to wax esters, which accumulated as intracellular lipid bodies. Conversion of acyl-ACP to fatty acids using endogenous cyanobacterial enzymes may allow biofuel production without transgenesis. PMID:23505484

  17. Predicting Potential Global Distributions of Two Miscanthus Grasses: Implications for Horticulture, Biofuel Production, and Biological Invasions

    PubMed Central

    Hager, Heather A.; Sinasac, Sarah E.; Gedalof, Ze’ev; Newman, Jonathan A.

    2014-01-01

    In many regions, large proportions of the naturalized and invasive non-native floras were originally introduced deliberately by humans. Pest risk assessments are now used in many jurisdictions to regulate the importation of species and usually include an estimation of the potential distribution in the import area. Two species of Asian grass (Miscanthus sacchariflorus and M. sinensis) that were originally introduced to North America as ornamental plants have since escaped cultivation. These species and their hybrid offspring are now receiving attention for large-scale production as biofuel crops in North America and elsewhere. We evaluated their potential global climate suitability for cultivation and potential invasion using the niche model CLIMEX and evaluated the models’ sensitivity to the parameter values. We then compared the sensitivity of projections of future climatically suitable area under two climate models and two emissions scenarios. The models indicate that the species have been introduced to most of the potential global climatically suitable areas in the northern but not the southern hemisphere. The more narrowly distributed species (M. sacchariflorus) is more sensitive to changes in model parameters, which could have implications for modelling species of conservation concern. Climate projections indicate likely contractions in potential range in the south, but expansions in the north, particularly in introduced areas where biomass production trials are under way. Climate sensitivity analysis shows that projections differ more between the selected climate change models than between the selected emissions scenarios. Local-scale assessments are required to overlay suitable habitat with climate projections to estimate areas of cultivation potential and invasion risk. PMID:24945154

  18. Cost structures and life cycle impacts of algal biomass and biofuel production

    NASA Astrophysics Data System (ADS)

    Christiansen, Katrina Lea

    2011-12-01

    Development and extraction of energy sources, energy production and energy use have huge economic, environmental and geopolitical impacts. Increasing energy demands in tandem with reductions in fossil fuel production has led to significant investments in research into alternative forms of energy. One that is promising but yet not commercially established is the production of biofuel from algae. This research quantitatively assessed the potential of algae biofuel production by examining its cost and environmental impacts. First, two models developed by the RAND corporation were employed to assess Cost Growth defined as the ratio of actual costs to estimated costs, and Plant Performance defined as the ratio of actual production levels to design performance, of three algal biofuel production technologies. The three algal biofuel production technologies examined to open raceway ponds (ORPs), photobioreactors (PBRs), and a system that couples PBRs to ORPs (PBR-ORPs). Though these analyses lack precision due to uncertainty, the results highlight the risks associated with implementing algal biofuel systems, as all scenarios examined were predicted to have Cost Growth, ranging from 1.2 to 1.8, and Plant Performance was projected as less than 50% of design performance for all cases. Second, the Framework the Evaluation of Biomass Energy Feedstocks (FEBEF) was used to assess the cost and environmental impacts of biodiesel produced from three algal production technologies. When these results were compared with ethanol from corn and biodiesel from soybeans, biodiesel from algae produced from the different technologies were estimated to be more expensive, suffered from low energy gains, and did not result in lower greenhouse gas emissions. To identify likely routes to making algal biofuels more competitive, a third study was undertaken. In this case, FEBEF was employed to examine pinch-points (defined as the most costly, energy consuming, greenhouse gas producing processes), in three algal production and fuel conversion scenarios, and then to estimate the improvement to cost and environmental impacts of proposed solutions to the pinch-points. These results illuminated significant opportunities to improve the economics and environmental impacts from producing algal biofuels produced in ORP, PBR, and PBR-ORPs. No single solution examined appeared to be sufficient to reduce the cost of fuel energy from algae to a competitive level with current petroleum diesel prices (4.20 /gal, ca. 28/GJ). However, if multiple pinch-points are overcome, e.g., simultaneous increases in (1) radiation use efficiency and (2) oil content or simultaneous decreases in (3) irrigation, (4) harvesting, (5) labor and (6)PBR costs are achieved then low Fuel Energy Costs (the ratio of total production and conversion costs to total energy available in the fuel) and low Total Energy Costs (the ratio of total production and conversion costs to total energy available in the fuel and co-products) are possible; with estimates ranging from 48 to 11 $/GJ.

  19. Flotation: A promising microalgae harvesting and dewatering technology for biofuels production.

    PubMed

    Ndikubwimana, Theoneste; Chang, Jingyu; Xiao, Zongyuan; Shao, Wenyao; Zeng, Xianhai; Ng, I-Son; Lu, Yinghua

    2016-03-01

    Microalgal biomass as renewable energy source is believed to be of great potential for reliable and sustainable biofuels production. However, microalgal biomass production is pinned by harvesting and dewatering stage thus hindering the developing and growing microalgae biotechnology industries. Flotation technology applied in mineral industry could be potentially applied in microalgae harvesting and dewatering, however substantial knowledge on different flotation units is essential. This paper presents an overview on different flotation units as promising cost-effective technologies for microalgae harvesting thus bestowing for further research in development and commercialization of microalgae based biofuels. Dispersed air flotation was found to be less energy consuming. Moreover, Jameson cell flotation and dispersed ozone flotation are believed to be energy efficient microalgae flotation approaches. Microalgae harvesting and dewatering by flotation is still at embryonic stage, therefore extended studies with the focus on life cycle assessment, sustainability of the flotation unit, optimization of the operating parameters using different algal species is imperative. Though there are a number of challenges in microalgae harvesting and dewatering, with well designed and developed cultivation, harvesting/dewatering, extraction and conversion technologies, progressively, microalgae technology will be of great potential for biological carbon sequestration, biofuels and biochemicals production. PMID:26928758

  20. Microalgae cultivation using an aquaculture wastewater as growth medium for biomass and biofuel production.

    PubMed

    Guo, Zhen; Liu, Yuan; Guo, Haiyan; Yan, Song; Mu, Jun

    2013-12-01

    Microalgae as a main feedstock has attracted much attention in recent years but is still not economically feasible due to high algal culture cost. The objective of this study was to develop a comprehensive eco-friendly technology for cultivating microalgae Platymonas subcordiformis using aquaculture wastewater as growth medium for biomass and biofuel production. Platymonas subcordiformis was grown in pretreated flounder aquaculture wastewaters taken from different stages. Each of wastewater contained different levels of nutrients. The biomass yield of microalgae and associated nitrogen and phosphorous removal were investigated. The results showed that algal cell density increased 8.9 times than the initial level. Platymonas subcordiformis removed nitrogen and phosphorus from wastewater with an average removal efficiency of 87%-95% for nitrogen and 98%-99% for phosphorus. It was feasible to couple the removal of nitrogen and phosphorus from wastewater to algal biomass and biofuel production. However, further studies are required to make this technologies economically viable for algae biofuel production. PMID:25078847

  1. Development of New Technologies of Solid and Gaseous Biofuel Production

    NASA Astrophysics Data System (ADS)

    Zaichenko, Victor

    Perspective direction of complex usage of biomass is connected with technologies of combined processing of organic fossil fuels and biomass with production of energy and carbon materials of high purity which can be used as high-calorific fuel and raw material for industrial technologies. Various directions of combined processing of a biomass are considered. The technology of pyrolysis of wood waste and peat and natural gas with productions of pure carbon materials and power gas with high content of hydrogen is presented. It is shown, that the combined technology of processing of biomass and natural gas is allowed to solve the problems connected with hydrogen production for power use.

  2. The effect of cellulosic biofuel production on water resources at a regional scale

    NASA Astrophysics Data System (ADS)

    Christopher, S. F.; Scheonholtz, S. H.; Nettles, J. E.

    2012-12-01

    The U.S. government has mandated production of 36 billion gallons of renewable fuels by 2022, of which 16 billion gallons are required to be cellulosic biofuels. Production of cellulosic biomass offers a promising alternative to corn-based systems because large-scale production of corn-based ethanol often requires irrigation and is associated with increased erosion, excess sediment export, and enhanced leaching of nitrogen and phosphorus. Although cultivation of switchgrass using standard agricultural practices is one option being considered for production of cellulosic biomass, intercropping cellulosic biofuel crops within managed forests could provide feedstock without primary land use change or the water resources impacts associated with annual crops. There are data sets and models that have been used to evaluate effects of agriculturally-based biofuel options on water quantity and quality, but the evaluation - from instrumentation through data analysis - is designed for these more disturbed systems and is not appropriate for the more subtle changes anticipated from a pine/switchgrass systems. Currently, there is no known hydrologic model that can explicitly assess the effect of intercropping on water resources. However, these models can evaluate the effects of growing switchgrass on water resources and would be useful in identifying the "worst case scenario". We used the Soil Water Assessment Tool (SWAT), a physically-based hydrologic model, to examine effects of large scale conversion of pine plantations to switchgrass biofuel production on water resources in the ~ 5 mil ha Tombigbee Watershed in the southeastern U.S. Publically available datasets were used as input to the model and for calibration. To improve calibration statistics, five tree age classes were added to the model to more appropriately represent existing forested systems in the region, which are not included within the standard model set-up. Results suggest land use conversions result in 4 and 28 % increase in mean annual stream discharge and NO3- yield, respectively. Our results will be essential to public policy makers as they plan for large-scale production of cellulosic biofuels, while sustaining water quality and quantity.

  3. Bermuda grass as feedstock for biofuel production: a review.

    PubMed

    Xu, Jiele; Wang, Ziyu; Cheng, Jay J

    2011-09-01

    Bermuda grass is a promising feedstock for the production of fuel ethanol in the Southern United States. This paper presents a review of the significant amount of research on the conversion of Bermuda grass to ethanol and a brief discussion on the factors affecting the biomass production in the field. The biggest challenge of biomass conversion comes from the recalcitrance of lignocellulose. A variety of chemical, physico-chemical, and biological pretreatment methods have been investigated to improve the digestibility of Bermuda grass with encouraging results reported. The subsequent enzymatic hydrolysis and fermentation steps have also been extensively studied and effectively optimized. It is expected that the development of genetic engineering technologies for the grass and fermenting organisms has the potential to greatly improve the economic viability of Bermuda grass-based fuel ethanol production systems. Other energy applications of Bermuda grass include anaerobic digestion for biogas generation and pyrolysis for syngas production. PMID:21683586

  4. Hybrid life-cycle assessment of algal biofuel production.

    PubMed

    Malik, Arunima; Lenzen, Manfred; Ralph, Peter J; Tamburic, Bojan

    2015-05-01

    The objective of this work is to establish whether algal bio-crude production is environmentally, economically and socially sustainable. To this end, an economic multi-regional input-output model of Australia was complemented with engineering process data on algal bio-crude production. This model was used to undertake hybrid life-cycle assessment for measuring the direct, as well as indirect impacts of producing bio-crude. Overall, the supply chain of bio-crude is more sustainable than that of conventional crude oil. The results indicate that producing 1 million tonnes of bio-crude will generate almost 13,000 new jobs and 4 billion dollars' worth of economic stimulus. Furthermore, bio-crude production will offer carbon sequestration opportunities as the production process is net carbon-negative. PMID:25465782

  5. Acetogenic mixotrophy: novel options for yield improvement in biofuels and biochemicals production.

    PubMed

    Fast, Alan G; Schmidt, Ellinor D; Jones, Shawn W; Tracy, Bryan P

    2015-06-01

    Mass yields of biofuels and chemicals from sugar fermentations are limited by the decarboxylation reactions involved in Embden-Meyerhof-Parnas (EMP) glycolysis. This paper reviews one route to recapture evolved CO2 using the Wood-Ljungdahl carbon fixation pathway (WLP) in a process called anaerobic, non-photosynthetic (ANP) mixotrophic fermentation. In ANP mixotrophic fermentation, the two molecules of CO2 and eight electrons produced from glycolysis are used by the WLP to generate three molecules of acetyl-CoA from glucose, rather than the two molecules that are produced by typical fermentation processes. In this review, we define the bounds of ANP mixotrophy, calculate the potential metabolic advantages, and discuss the viability in a number of host organisms. Additionally, we highlight recent accomplishments in the field, including the recent discovery of electron bifurcation in acetogens, and close with recommendations to realize mixotrophic biofuel and biochemical production. PMID:25498292

  6. Engineering of a novel cellulose-adherent cellulolytic Saccharomyces cerevisiae for cellulosic biofuel production.

    PubMed

    Liu, Zhuo; Ho, Shih-Hsin; Sasaki, Kengo; den Haan, Riaan; Inokuma, Kentaro; Ogino, Chiaki; van Zyl, Willem H; Hasunuma, Tomohisa; Kondo, Akihiko

    2016-01-01

    Cellulosic biofuel is the subject of increasing attention. The main obstacle toward its economic feasibility is the recalcitrance of lignocellulose requiring large amount of enzyme to break. Several engineered yeast strains have been developed with cellulolytic activities to reduce the need for enzyme addition, but exhibiting limited effect. Here, we report the successful engineering of a cellulose-adherent Saccharomyces cerevisiae displaying four different synergistic cellulases on the cell surface. The cellulase-displaying yeast strain exhibited clear cell-to-cellulose adhesion and a "tearing" cellulose degradation pattern; the adhesion ability correlated with enhanced surface area and roughness of the target cellulose fibers, resulting in higher hydrolysis efficiency. The engineered yeast directly produced ethanol from rice straw despite a more than 40% decrease in the required enzyme dosage for high-density fermentation. Thus, improved cell-to-cellulose interactions provided a novel strategy for increasing cellulose hydrolysis, suggesting a mechanism for promoting the feasibility of cellulosic biofuel production. PMID:27079382

  7. Historical Perspective of Biofuels: Learning from the Past to Rediscover the Future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This issue of in vitro plant is dedicated to various aspects of biofuel research and development. The editors have sought the experts in this field and solicited manuscripts for this special issue publication from various academic institutions, government (USDA, DOE), industry (Mendel, Alellyx, Can...

  8. Conventional and molecular breeding for improvement of biofuel crops: past, present and future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    First-generation biofuels are derived from food and feed crops rich in sugar, starch, or oil, such as sugarcane (Saccharum hyb.), maize (Zea mays), or soybean (Glycine max), as these are easily converted into liquid fuels. However, these crops alone cannot meet the projected demand for fuel, so sec...

  9. Regional Environmental Impacts of Biofuel Feedstock Production--Scaling Biogeochemical Cycles in Space and Time

    NASA Astrophysics Data System (ADS)

    Vanloocke, A.; Bernacchi, C.

    2008-12-01

    Recently there has been increasing socio-economic and scientific interest in the use of alternative sources of energy to offset the negative effects of current fossil fuel dependence and consequent greenhouse gas emissions. Currently, one of the most popular alternatives is to use ethanol produced from domestically grown crops for use as fuel in the transportation sector. In 2007, over 7.5 billion gallons of ethanol were produced in the U.S. from corn, a traditional food crop. Recent research indicates that it may be logistically impractical, ecologically counterproductive (i.e. a net carbon source), and economically devastating to produce ethanol from crops previously grown to produce food. The EBI (Energy Biosciences Institute, at University of California Berkley and University of Illinois Urbana-Champaign) is now conducting research to assess the ability of traditional crops as well as dedicated biofuel feedstocks (e.g. Panicum virgatum (switchgrass), Miscanthus x Giganteus (Miscanthus), and Saccharum spp (sugar cane)) to provide a productive and sustainable alternative to fossil fuel. This is an important step to take before implementing the large-scale growth necessary to meet U.S. energy needs .A process-based terrestrial ecosystem model, Agro-IBIS (Agricultural Integrated Biosphere Simulator) was adapted to simulate the growth of Miscanthus. The model was calibrated using data collected from sites at the University of Illinois south farms. Simulations indicated significant implications on the regional carbon and water budgets. Next this locally validated method will be extrapolated to simulate the regional scale growth of Miscanthus in the Midwestern U.S. and sugarcane in Brazil and a similar analysis will be conducted for switchgrass. The results should provide insight on optimal land-use decisions and legislation that regard meeting energy demands and mitigating climate change in the near future.

  10. Future U.S. water consumption : The role of energy production.

    SciTech Connect

    Elcock, D.; Environmental Science Division

    2010-06-01

    This study investigates how meeting domestic energy production targets for both fossil and renewable fuels may affect future water demand. It combines projections of energy production developed by the U.S. Department of Energy with estimates of water consumption on a per-unit basis (water-consumption coefficients) for coal, oil, gas, and biofuels production, to estimate and compare the domestic freshwater consumed. Although total domestic freshwater consumption is expected to increase by nearly 7% between 2005 and 2030, water consumed for energy production is expected to increase by nearly 70%, and water consumed for biofuels (biodiesel and ethanol) production is expected to increase by almost 250%. By 2030, water consumed in the production of biofuels is projected to account for nearly half of the total amount of water consumed in the production of all energy fuels. Most of this is for irrigation, and the West North Central Region is projected to consume most of this water in 2030. These findings identify an important potential future conflict between renewable energy production and water availability that warrants further investigation and action to ensure that future domestic energy demand can be met in an economically efficient and environmentally sustainable manner.

  11. Soil carbon sequestration and land use change associated with biofuel production: Empirical evidence

    SciTech Connect

    Qin, Zhangcai; Dunn, Jennifer B.; Kwon, Hoyoung; Mueller, Steffen; Wander, Michelle M.

    2016-01-01

    Soil organic carbon (SOC) change can be a major impact of land use change (LUC) associated with biofuel feedstock production. By collecting and analyzing data from worldwide field observations with major LUCs from cropland, grassland and forest to lands producing biofuel crops (i.e., corn, switchgrass, Miscanthus, poplar and willow), we were able to estimate SOC response ratios and sequestration rates and evaluate the effects of soil depth and time scale on SOC change. Both the amount and rate of SOC change were highly dependent on the specific land transition. Irrespective of soil depth or time horizon, cropland conversions resulted in an overall SOC gain of 6-14% relative to initial SOC level, while conversion from grassland or forest to corn (without residue removal) or poplar caused significant carbon loss (9-35%). No significant SOC changes were observed in land converted from grasslands or forests to switchgrass, Miscanthus or willow. The SOC response ratios were similar in both 0-30 and 0-100 cm soil depths in most cases, suggesting SOC changes in deep soil and that use of top soil only for SOC accounting in biofuel life cycle analysis (LCA) might underestimate total SOC changes. Soil carbon sequestration rates varied greatly among studies and land transition types. Generally, the rates of SOC change tended to be the greatest during the 10 years following land conversion, and had declined to approach 0 within about 20 years for most LUCs. Observed trends in SOC change were generally consistent with previous reports. Soil depth and duration of study significantly influence SOC change rates and so should be considered in carbon emission accounting in biofuel LCA. High uncertainty remains for many perennial systems, field trials and modeling efforts are needed to determine the site- and system-specific rates and direction of change associated with their production.

  12. Improving Biocatalysts for the Production of Biofuels from Lignocellulosic Feedstocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Industrial-scale production of fuel ethanol from biomass continues to show promise for relieving dependence upon petroleum-based transportation fuels. The limited range of materials that can be practically converted, however, continues to be an obstacle to the lignocellulosic revolution. Therefore...

  13. Can Sweet Sorghum be used for Biofuel Production?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sweet sorghum germplasm collection (1280 accessions) is maintained at the Plant Genetic Resources Conservation Unit, Griffin, Georgia. Sweet sorghum contains a high amount of sucrose (2.5% - 13%) that has been used for syrup, molasses, and ethanol production. Furthermore, as a high energy capt...

  14. Rotating algal biofilm reactor and spool harvester for wastewater treatment with biofuels by-products.

    PubMed

    Christenson, Logan B; Sims, Ronald C

    2012-07-01

    Maximizing algae production in a wastewater treatment process can aid in the reduction of soluble nitrogen and phosphorus concentrations in the wastewater. If harvested, the algae-based biomass offers the added benefit as feedstock for the production of biofuels and bioproducts. However, difficulties in harvesting, concentrating, and dewatering the algae-based biomass have limited the development of an economically feasible treatment and production process. When algae-based biomass is grown as a surface attached biofilm as opposed to a suspended culture, the biomass is naturally concentrated and more easily harvested. This can lead to less expensive removal of the biomass from wastewater, and less expensive downstream processing in the production of biofuels and bioproducts. In this study, a novel rotating algal biofilm reactor (RABR) was designed, built, and tested at bench (8 L), medium (535 L), and pilot (8,000 L) scales. The RABR was designed to operate in the photoautotrophic conditions of open tertiary wastewater treatment, producing mixed culture biofilms made up of algae and bacteria. Growth substrata were evaluated for attachment and biofilm formation, and an effective substratum was discovered. The RABR achieved effective nutrient reduction, with average removal rates of 2.1 and 14.1 g m(-2) day(-1) for total dissolved phosphorus and total dissolved nitrogen, respectively. Biomass production ranged from 5.5 g m(-2) day(-1) at bench scale to as high as 31 g m(-2) day(-1) at pilot scale. An efficient spool harvesting technique was also developed at bench and medium scales to obtain a concentrated product (12-16% solids) suitable for further processing in the production of biofuels and bioproducts. PMID:22328283

  15. 7 CFR 4288.137 - Succession and loss of control of advanced biofuel facilities and production.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    .... Payments will be made only for eligible advanced biofuels produced at an advanced biofuel facility owned or... 7 Agriculture 15 2014-01-01 2014-01-01 false Succession and loss of control of advanced biofuel... PROGRAMS Advanced Biofuel Payment Program General Provisions Payment Provisions § 4288.137 Succession...

  16. 7 CFR 4288.137 - Succession and loss of control of advanced biofuel facilities and production.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... eligible advanced biofuels produced at an advanced biofuel facility owned or controlled by an eligible... 7 Agriculture 15 2013-01-01 2013-01-01 false Succession and loss of control of advanced biofuel... PROGRAMS Advanced Biofuel Payment Program General Provisions § 4288.137 Succession and loss of control...

  17. 7 CFR 4288.137 - Succession and loss of control of advanced biofuel facilities and production.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... eligible advanced biofuels produced at an advanced biofuel facility owned or controlled by an eligible... 7 Agriculture 15 2012-01-01 2012-01-01 false Succession and loss of control of advanced biofuel... PROGRAMS Advanced Biofuel Payment Program General Provisions § 4288.137 Succession and loss of control...

  18. Techno-Economic Analysis of Biofuels Production Based on Gasification

    SciTech Connect

    Swanson, R. M.; Platon, A.; Satrio, J. A.; Brown, R. C.; Hsu, D. D.

    2010-11-01

    This study compares capital and production costs of two biomass-to-liquid production plants based on gasification. The first biorefinery scenario is an oxygen-fed, low-temperature (870?C), non-slagging, fluidized bed gasifier. The second scenario is an oxygen-fed, high-temperature (1,300?C), slagging, entrained flow gasifier. Both are followed by catalytic Fischer-Tropsch synthesis and hydroprocessing to naphtha-range (gasoline blend stock) and distillate-range (diesel blend stock) liquid fractions. Process modeling software (Aspen Plus) is utilized to organize the mass and energy streams and cost estimation software is used to generate equipment costs. Economic analysis is performed to estimate the capital investment and operating costs. Results show that the total capital investment required for nth plant scenarios is $610 million and $500 million for high-temperature and low-temperature scenarios, respectively. Product value (PV) for the high-temperature and low-temperature scenarios is estimated to be $4.30 and $4.80 per gallon of gasoline equivalent (GGE), respectively, based on a feedstock cost of $75 per dry short ton. Sensitivity analysis is also performed on process and economic parameters. This analysis shows that total capital investment and feedstock cost are among the most influential parameters affecting the PV.

  19. Bio-Fuel Production Assisted with High Temperature Steam Electrolysis

    SciTech Connect

    Grant Hawkes; James O'Brien; Michael McKellar

    2012-06-01

    Two hybrid energy processes that enable production of synthetic liquid fuels that are compatible with the existing conventional liquid transportation fuels infrastructure are presented. Using biomass as a renewable carbon source, and supplemental hydrogen from high-temperature steam electrolysis (HTSE), these two hybrid energy processes have the potential to provide a significant alternative petroleum source that could reduce dependence on imported oil. The first process discusses a hydropyrolysis unit with hydrogen addition from HTSE. Non-food biomass is pyrolyzed and converted to pyrolysis oil. The pyrolysis oil is upgraded with hydrogen addition from HTSE. This addition of hydrogen deoxygenates the pyrolysis oil and increases the pH to a tolerable level for transportation. The final product is synthetic crude that could then be transported to a refinery and input into the already used transportation fuel infrastructure. The second process discusses a process named Bio-Syntrolysis. The Bio-Syntrolysis process combines hydrogen from HTSE with CO from an oxygen-blown biomass gasifier that yields syngas to be used as a feedstock for synthesis of liquid synthetic crude. Conversion of syngas to liquid synthetic crude, using a biomass-based carbon source, expands the application of renewable energy beyond the grid to include transportation fuels. It can also contribute to grid stability associated with non-dispatchable power generation. The use of supplemental hydrogen from HTSE enables greater than 90% utilization of the biomass carbon content which is about 2.5 times higher than carbon utilization associated with traditional cellulosic ethanol production. If the electrical power source needed for HTSE is based on nuclear or renewable energy, the process is carbon neutral. INL has demonstrated improved biomass processing prior to gasification. Recyclable biomass in the form of crop residue or energy crops would serve as the feedstock for this process. A process model of syngas production using high temperature electrolysis and biomass gasification is presented. Process heat from the biomass gasifier is used to heat steam for the hydrogen production via the high temperature steam electrolysis process. Oxygen produced form the electrolysis process is used to control the oxidation rate in the oxygen-blown biomass gasifier.

  20. The benefits of biofuels

    SciTech Connect

    Hinman, N.D.

    1997-07-01

    This article discusses the economic, environmental, and national security advantages of using biofuels instead of petroleum products in vehicles. Smog and carbon monoxide, two of the most trouble-some urban air pollutants, are largely caused by combustion of conventional petroleum based fuels. Topics include sustainable transportation fuels, emphasis on ethanol, the process of producing biofuels, and the growing market for biofuels. 1 tab.

  1. Projections of Biofuel Growth Patterns Reveal the Potential Importance of Nitrogen Fixation for Miscanthus Productivity

    NASA Astrophysics Data System (ADS)

    Davis, S. C.; Parton, W. J.; Dohleman, F. G.; Gottel, N. R.; Smith, C. M.; Kent, A. D.; Delucia, E. H.

    2008-12-01

    Demand for liquid biofuels is increasing because of the disparity between fuel demand and supply. Relative to grain crops, the more intensive harvest required for second generation liquid biofuel production leads to the removal of significantly more carbon and nitrogen from the soil. These elements are conventionally litter products of crops that are returned to the soil and can accumulate over time. This loss of organic matter represents a management challenge because the energy cost associated with fertilizers or external sources of organic matter reduce the net energy value of the biofuel crops. Plants that have exceptional strategies for exploiting nutrients may be the most viable options for sustainable biofuel yields because of low management and energy cost. Miscanthus x giganteus has high N retranslocation rates, maintains high photosynthetic rates over a large temperature range, exploits a longer-than-average growing season, and yields at least twice the biomass of other candidate biofuel grass crops (i.e. switchgrass). We employed the DAYCENT model to project potential productivity of Miscanthus, corn, switchgrass, and mixed prairie communities based on our current knowledge of these species. Ecosystem process descriptions that have been validated for many crop species did not accurately predict Miscanthus yields and lead to new hypotheses about unknown N cycling mechanisms for this species. We tested the hypothesis that Miscanthus hosts N-fixing bacteria in several ways. First, we used enrichment culture and molecular methods to detect N-fixing bacteria in Miscanthus. Then, we demonstrated the plant-growth promoting effect of diazotrophs isolated from Miscanthus rhizomes on a model grass. And finally, we applied 15N2 to the soil and rooting zone of field grown Miscanthus plants to determine if atmospheric N2 was incorporated into plant tissue, a process that requires N-fixation. These experiments are the first tests of N-fixation in Miscanthus x giganteus, and the ecosystem model allowed us to project how much nitrogen may be obtained from N-fixation to support sustainable high biomass yields.

  2. Natural products as biofuels and bio-based chemicals: fatty acids and isoprenoids.

    PubMed

    Beller, Harry R; Lee, Taek Soon; Katz, Leonard

    2015-09-23

    Although natural products are best known for their use in medicine and agriculture, a number of fatty acid-derived and isoprenoid natural products are being developed for use as renewable biofuels and bio-based chemicals. This review summarizes recent work on fatty acid-derived compounds (fatty acid alkyl esters, fatty alcohols, medium- and short-chain methyl ketones, alkanes, ?-olefins, and long-chain internal alkenes) and isoprenoids, including hemiterpenes (e.g., isoprene and isopentanol), monoterpenes (e.g., limonene), and sesquiterpenes (e.g., farnesene and bisabolene). PMID:26216573

  3. Dissecting and engineering metabolic and regulatory networks of thermophilic bacteria for biofuel production.

    PubMed

    Lin, Lu; Xu, Jian

    2013-11-01

    Interest in thermophilic bacteria as live-cell catalysts in biofuel and biochemical industry has surged in recent years, due to their tolerance of high temperature and wide spectrum of carbon-sources that include cellulose. However their direct employment as microbial cellular factories in the highly demanding industrial conditions has been hindered by uncompetitive biofuel productivity, relatively low tolerance to solvent and osmic stresses, and limitation in genome engineering tools. In this work we review recent advances in dissecting and engineering the metabolic and regulatory networks of thermophilic bacteria for improving the traits of key interest in biofuel industry: cellulose degradation, pentose-hexose co-utilization, and tolerance of thermal, osmotic, and solvent stresses. Moreover, new technologies enabling more efficient genetic engineering of thermophiles were discussed, such as improved electroporation, ultrasound-mediated DNA delivery, as well as thermo-stable plasmids and functional selection systems. Expanded applications of such technological advancements in thermophilic microbes promise to substantiate a synthetic biology perspective, where functional parts, module, chassis, cells and consortia were modularly designed and rationally assembled for the many missions at industry and nature that demand the extraordinary talents of these extremophiles. PMID:23510903

  4. Quantifying the regional water footprint of biofuel production by incorporating hydrologic modeling

    NASA Astrophysics Data System (ADS)

    Wu, M.; Chiu, Y.; Demissie, Y.

    2012-10-01

    A spatially explicit life cycle water analysis framework is proposed, in which a standardized water footprint methodology is coupled with hydrologic modeling to assess blue water, green water (rainfall), and agricultural grey water discharge in the production of biofuel feedstock at county-level resolution. Grey water is simulated via SWAT, a watershed model. Evapotranspiration (ET) estimates generated with the Penman-Monteith equation and crop parameters were verified by using remote sensing results, a satellite-imagery-derived data set, and other field measurements. Crop irrigation survey data are used to corroborate the estimate of irrigation ET. An application of the concept is presented in a case study for corn-stover-based ethanol grown in Iowa (United States) within the Upper Mississippi River basin. Results show vast spatial variations in the water footprint of stover ethanol from county to county. Producing 1 L of ethanol from corn stover growing in the Iowa counties studied requires from 4.6 to 13.1 L of blue water (with an average of 5.4 L), a majority (86%) of which is consumed in the biorefinery. The county-level green water (rainfall) footprint ranges from 760 to 1000 L L-1. The grey water footprint varies considerably, ranging from 44 to 1579 L, a 35-fold difference, with a county average of 518 L. This framework can be a useful tool for watershed- or county-level biofuel sustainability metric analysis to address the heterogeneity of the water footprint for biofuels.

  5. Ultrasonic waste activated sludge disintegration for recovering multiple nutrients for biofuel production.

    PubMed

    Xie, Guo-Jun; Liu, Bing-Feng; Wang, Qilin; Ding, Jie; Ren, Nan-Qi

    2016-04-15

    Waste activated sludge is a valuable resource containing multiple nutrients, but is currently treated and disposed of as an important source of pollution. In this work, waste activated sludge after ultrasound pretreatment was reused as multiple nutrients for biofuel production. The nutrients trapped in sludge floc were transferred into liquid medium by ultrasonic disintegration during first 30 min, while further increase of pretreatment time only resulted in slight increase of nutrients release. Hydrogen production by Ethanoligenens harbinense B49 from glucose significantly increased with the concentration of ultrasonic sludge, and reached maximum yield of 1.97 mol H2/mol glucose at sludge concentration of 7.75 g volatile suspended solids/l. Without addition of any other chemicals, waste molasses rich in carbohydrate was efficiently turned into hydrogen with yield of 189.34 ml H2/g total sugar by E. harbinense B49 using ultrasonic sludge as nutrients. The results also showed that hydrogen production using pretreated sludge as multiple nutrients was higher than those using standard nutrients. Acetic acid produced by E. harbinense B49 together with the residual nutrients in the liquid medium were further converted into hydrogen (271.36 ml H2/g total sugar) by Rhodopseudomonas faecalis RLD-53 through photo fermentation, while ethanol was the sole end product with yield of 220.26 mg/g total sugar. Thus, pretreated sludge was an efficient nutrients source for biofuel production, which could replace the standard nutrients. This research provided a novel strategy to achieve environmental friendly sludge disposal and simultaneous efficient biofuel recovery from organic waste. PMID:26896823

  6. [Lipid biofuel production with microalgae: potential and challenges].

    PubMed

    Cadoret, Jean-Paul; Bernard, Olivier

    2008-01-01

    Microalgae can accumulate fatty acids up to 80% of their dry weight (Chisti 2007). As a consequence the yield per hectare could be higher by a factor of 30 compared to terrestrial oleaginous species. Biodiversity of microalgae is enormous. It is estimated that there are between 200 000 and several million species. Such diversity is an unexplored potential for research and industry. In comparison to terrestrial oleaginous species, microalgae have many characteristics addressing environmental problems with a drastically enhanced oil production. Microalgae are currently generating mediatic enthusiasm, and many start-ups are investing this niche. Nevertheless there are still locks to undo via upstream search, before the expected returns and costs are met and before these technologies can be developed at a large scale. PMID:18980742

  7. Catalytic Fast Pyrolysis for the Production of the Hydrocarbon Biofuels

    SciTech Connect

    Nimlos, M. R.; Robichaud, D. J.; Mukaratate, C.; Donohoe, B. S.; Iisa, K.

    2013-01-01

    Catalytic fast pyrolysis is a promising technique for conversion of biomass into hydrocarbons for use as transportation fuels. For over 30 years this process has been studied and it has been demonstrated that oils can be produced with high concentrations of hydrocarbons and low levels of oxygen. However, the yields from this type of conversion are typically low and the catalysts, which are often zeolites, are quickly deactivated through coking. In addition, the hydrocarbons produced are primarily aromatic molecules (benzene, toluene, xylene) that not desirable for petroleum refineries and are not well suited for diesel or jet engines. The goals of our research are to develop new multifunction catalysts for the production of gasoline, diesel and jet fuel range molecules and to improve process conditions for higher yields and low coking rates. We are investigating filtration and the use of hydrogen donor molecules to improve catalyst performance.

  8. Biofuel Production Datasets from DOE's Bioenergy Knowledge Discovery Framework (KDF)

    DOE Data Explorer

    The Bioenergy Knowledge Discovery Framework invites users to discover the power of bioenergy through an interface that provides extensive access to research data and literature, GIS mapping tools, and collaborative networks. The Bioenergy KDF supports efforts to develop a robust and sustainable bioenergy industry. The KDF facilitates informed decision making by providing a means to synthesize, analyze, and visualize vast amounts of information in a relevant and succinct manner. It harnesses Web 2.0 and social networking technologies to build a collective knowledge system that can better examine the economic and environmental impacts of development options for biomass feedstock production, biorefineries, and related infrastructure. [copied from https://www.bioenergykdf.net/content/about]

    Holdings include datasets, models, and maps and the collections arel growing due to both DOE contributions and data uploads from individuals.

  9. Understanding and engineering enzymes for enhanced biofuel production.

    SciTech Connect

    Simmons, Blake Alexander; Volponi, Joanne V.; Sapra, Rajat; Faulon, Jean-Loup Michel; Buffleben, George M.; Roe, Diana C.

    2009-01-01

    Today, carbon-rich fossil fuels, primarily oil, coal and natural gas, provide 85% of the energy consumed in the United States. The release of greenhouse gases from these fuels has spurred research into alternative, non-fossil energy sources. Lignocellulosic biomass is renewable resource that is carbon-neutral, and can provide a raw material for alternative transportation fuels. Plant-derived biomass contains cellulose, which is difficult to convert to monomeric sugars for production of fuels. The development of cost-effective and energy-efficient processes to transform the cellulosic content of biomass into fuels is hampered by significant roadblocks, including the lack of specifically developed energy crops, the difficulty in separating biomass components, the high costs of enzymatic deconstruction of biomass, and the inhibitory effect of fuels and processing byproducts on organisms responsible for producing fuels from biomass monomers. One of the main impediments to more widespread utilization of this important resource is the recalcitrance of cellulosic biomass and techniques that can be utilized to deconstruct cellulosic biomass.

  10. Perennial grass production for biofuels: Soil conservation considerations

    SciTech Connect

    McLaughlin, S.B.; Bransby, D.I.; Parrish, D.

    1994-12-31

    The increased use of renewable fuels for energy offers the United States a mechanism for significantly reducing national dependency on imported oil, reducing greenhouse gas emissions, and improving regional agricultural economies. As mandated by law, a wide range of issues have been raised regarding the net environmental impacts of implementation of these new technologies. While uncertainties regarding both positive and negative environmental influences still exist in many areas of this new technology, it is now possible to address with substantial certainty the positive aspects of perennial herbaceous energy crops on several important soil conservation issues. Past experience with forage grasses and recent research with switchgrass, a warm season perennial forage grass selected as one of the model bioenergy species, indicates that important benefits will be gained in the area of soil conservation as grasses replace energy-intensive annual row crops. These include reduced erosion, improved conservation of water and nutrients, and increased productivity of soil by the deep and vigorous rooting systems of perennial warm-season grasses.

  11. Perennial grass production for biofuels: Soil conversion considerations

    SciTech Connect

    McLaughlin, S.B.; Bransby, D.I.; Parrish, D.

    1994-10-01

    The increased use of renewable fuels for energy offers the United States a mechanism for significantly reducing national dependency on imported oil, reducing greenhouse gas emissions, and improving regional agricultural economies. As mandated by law, a wide range of issues have been raised regarding the net environmental impacts of implementation of these new technologies. While uncertainties regarding both positive and negative environmental influences still exist in many areas of this new technology, it is now possible to address with substantial certainty the positive aspects of perennial herbaceous energy crops on several important soil conservation issues. Past experience with forage grasses and recent research with switchgrass. A warm season perennial forage grass selected as one of the model bioenergy species, indicates that important benefits will be gained in the area of soil conservation as grasses replace energy-intensive annual row crops. These include reduced erosion, improved conservation of water and nutrients, and increased productivity of soils by the deep and vigorous rooting systems of perennial warm-season gasses.

  12. Microwave-assisted pyrolysis of microalgae for biofuel production.

    PubMed

    Du, Zhenyi; Li, Yecong; Wang, Xiaoquan; Wan, Yiqin; Chen, Qin; Wang, Chenguang; Lin, Xiangyang; Liu, Yuhuan; Chen, Paul; Ruan, Roger

    2011-04-01

    The pyrolysis of Chlorella sp. was carried out in a microwave oven with char as microwave reception enhancer. The results indicated that the maximum bio-oil yield of 28.6% was achieved under the microwave power of 750 W. The bio-oil properties were characterized with elemental, GC-MS, GPC, FTIR, and thermogravimetric analysis. The algal bio-oil had a density of 0.98 kg/L, a viscosity of 61.2 cSt, and a higher heating value (HHV) of 30.7 MJ/kg. The GC-MS results showed that the bio-oils were mainly composed of aliphatic hydrocarbons, aromatic hydrocarbons, phenols, long chain fatty acids and nitrogenated compounds, among which aliphatic and aromatic hydrocarbons (account for 22.18% of the total GC-MS spectrum area) are highly desirable compounds as those in crude oil, gasoline and diesel. The results in this study indicate that fast growing algae are a promising source of feedstock for advanced renewable fuel production via microwave-assisted pyrolysis (MAP). PMID:21316940

  13. Water for Food, Energy, and the Environment: Assessing Streamflow Impacts of Increasing Cellulosic Biofuel Crop Production in the Corn Belt

    NASA Astrophysics Data System (ADS)

    Yaeger, M. A.; Housh, M.; Ng, T.; Cai, X.; Sivapalan, M.

    2012-12-01

    The recently expanded Renewable Fuel Standard, which now requires 36 billion gallons of renewable fuels by 2022, has increased demand for biofuel refinery feedstocks. Currently, biofuel production consists mainly of corn-based ethanol, but concern over increasing nitrate levels resulting from increased corn crop fertilization has prompted research into alternative biofuel feedstocks. Of these, high-yielding biomass crops such as Miscanthus have been suggested for cellulose-based ethanol production. Because these perennial crops require less fertilization and do not need tilling, increasing land area in the Midwest planted with Miscanthus would result in less nitrate pollution to the Gulf of Mexico. There is a tradeoff, however, as Miscanthus also has higher water requirements than conventional crops in the region. This could pose a serious problem for riparian ecosystems and other streamflow users such as municipalities and biofuel refineries themselves, as the lowest natural flows in this region coincide with the peak of the growing season. Moreover, low flow reduction may eventually cut off the water quality benefit that planting Miscanthus provides. Therefore, for large-scale cellulosic ethanol production to be sustainable, it is important to understand how the watershed will respond to this change in land and water use. To this end a detailed data analysis of current watershed conditions has been combined with hydrologic modeling to gain deeper insights into how catchments in the highly agricultural central IL watershed of the Sangamon River respond to current and future land and water usage, with the focus on the summer low-flow season. In addition, an integrated systems optimization model has been developed that combines hydrologic, agro-biologic, engineering infrastructural, and economic inputs to provide optimal scenarios of crop type and area and corresponding refinery locations and capacities. Through this integrated modeling framework, we address the key hypothesis: what may benefit the human system (farms, refineries, cities) may damage the environment. The hydrological and optimization models will be run interactively, with the optimization model run for 10 years and the resulting land use solution then used in the SWAT hydrologic model to provide more detailed information on river/ecosystem impacts, which are assessed using low flow analysis. Problem areas highlighted by this analysis can be targeted by implementing flow requirements at different locations in the watershed; these constraints are then added to the optimization model which is run for another 10 years, and the new solution again analyzed in more detail to assess the effectiveness of the imposed environmental measures. Preliminary results show that under proposed subsidies and current crop prices, the percentage of land planted with Miscanthus will increase to environmentally unsustainable levels, but that implementing flow and water quality constraints can mitigate the damage to some extent. Moreover, tributary and mainstem subwatersheds in the Sangamon do not respond equally, even in this very homogenous region, and thus the spatial context is important for understanding the tradeoffs between economic and hydrologic benefits, which become increasingly important in creating sustainable biofuel production.

  14. Advancing Commercialization of Algal Biofuels Through Increased Biomass Productivity and Technology Integration

    SciTech Connect

    Bai, Xuemei; Sabarsky, Martin

    2013-09-30

    Cellana is a leading developer of algae-based bioproducts, and its pre-commercial production of marine microalgae takes place at Cellana?s Kona Demonstration Facility (KDF) in Hawaii. KDF is housing more than 70 high-performing algal strains for different bioproducts, of which over 30 have been grown outside at scale. So far, Cellana has produced more than 10 metric tons of algal biomass for the development of biofuels, animal feed, and high-value nutraceuticals. Cellana?s ALDUO algal cultivation technology allows Cellana to grow non-extremophile algal strains at large scale with no contamination disruptions. Cellana?s research and production at KDF have addressed three major areas that are crucial for the commercialization of algal biofuels: yield improvement, cost reduction, and the overall economics. Commercially acceptable solutions have been developed and tested for major factors limiting areal productivity of algal biomass and lipids based on years of R&D work conducted at KDF. Improved biomass and lipid productivity were achieved through strain improvement, culture management strategies (e.g., alleviation of self-shading, de-oxygenation, and efficient CO2 delivery), and technical advancement in downstream harvesting technology. Cost reduction was achieved through optimized CO2 delivery system, flue gas utilization technology, and energy-efficient harvesting technology. Improved overall economics was achieved through a holistic approach by integration of high-value co-products in the process, in addition to yield improvements and cost reductions.

  15. An Integrated Assessment of Location-Dependent Scaling for Microalgae Biofuel Production Facilities

    SciTech Connect

    Coleman, Andre M.; Abodeely, Jared; Skaggs, Richard; Moeglein, William AM; Newby, Deborah T.; Venteris, Erik R.; Wigmosta, Mark S.

    2014-07-01

    Successful development of a large-scale microalgae-based biofuels industry requires comprehensive analysis and understanding of the feedstock supply chain—from facility siting/design through processing/upgrading of the feedstock to a fuel product. The evolution from pilot-scale production facilities to energy-scale operations presents many multi-disciplinary challenges, including a sustainable supply of water and nutrients, operational and infrastructure logistics, and economic competitiveness with petroleum-based fuels. These challenges are addressed in part by applying the Integrated Assessment Framework (IAF)—an integrated multi-scale modeling, analysis, and data management suite—to address key issues in developing and operating an open-pond facility by analyzing how variability and uncertainty in space and time affect algal feedstock production rates, and determining the site-specific “optimum” facility scale to minimize capital and operational expenses. This approach explicitly and systematically assesses the interdependence of biofuel production potential, associated resource requirements, and production system design trade-offs. The IAF was applied to a set of sites previously identified as having the potential to cumulatively produce 5 billion-gallons/year in the southeastern U.S. and results indicate costs can be reduced by selecting the most effective processing technology pathway and scaling downstream processing capabilities to fit site-specific growing conditions, available resources, and algal strains.

  16. Impacts of biofuels production alternatives on water quantity and quality in the Iowa River Basin

    USGS Publications Warehouse

    Wu, Y.; Liu, S.

    2012-01-01

    Corn stover as well as perennial grasses like switchgrass (Panicum virgatum) and miscanthus are being considered as candidates for the second generation biofuel feedstocks. However, the challenges to biofuel development are its effects on the environment, especially water quality. This study evaluates the long-term impacts of biofuel production alternatives (e.g., elevated corn stover removal rates and the potential land cover change) on an ecosystem with a focus on biomass production, soil erosion, water quantity and quality, and soil nitrate nitrogen concentration at the watershed scale. The Soil and Water Assessment Tool (SWAT) was modified for setting land cover change scenarios and applied to the Iowa River Basin (a tributary of the Upper Mississippi River Basin). Results show that biomass production can be sustained with an increased stover removal rate as long as the crop demand for nutrients is met with appropriate fertilization. Although a drastic increase (4.7–70.6%) in sediment yield due to erosion and a slight decrease (1.2–3.2%) in water yield were estimated with the stover removal rate ranging between 40% and 100%, the nitrate nitrogen load declined about 6–10.1%. In comparison to growing corn, growing either switchgrass or miscanthus can reduce sediment erosion greatly. However, land cover changes from native grass to switchgrass or miscanthus would lead to a decrease in water yield and an increase in nitrate nitrogen load. In contrast to growing switchgrass, growing miscanthus is more productive in generating biomass, but its higher water demand may reduce water availability in the study area.

  17. Soil Carbon Change and Net Energy Associated with Biofuel Production on Marginal Lands: A Regional Modeling Perspective

    SciTech Connect

    Bandaru, Varaprasad; Izaurralde, Roberto C.; Manowitz, David H.; Link, Robert P.; Zhang, Xuesong; Post, W. M.

    2013-12-01

    The use of marginal lands (MLs) for biofuel production has been contemplated as a promising solution for meeting biofuel demands. However, there have been concerns with spatial location of MLs, their inherent biofuel potential, and possible environmental consequences with the cultivation of energy crops. Here, we developed a new quantitative approach that integrates high-resolution land cover and land productivity maps and uses conditional probability density functions for analyzing land use patterns as a function of land productivity to classify the agricultural lands. We subsequently applied this method to determine available productive croplands (P-CLs) and non-crop marginal lands (NC-MLs) in a nine-county Southern Michigan. Furthermore, Spatially Explicit Integrated Modeling Framework (SEIMF) using EPIC (Environmental Policy Integrated Climate) was used to understand the net energy (NE) and soil organic carbon (SOC) implications of cultivating different annual and perennial production systems.

  18. Vermont Biofuels Initiative: Local Production for Local Use to Supply a Portion of Vermont's Energy Needs

    SciTech Connect

    Sawyer, Scott; Kahler, Ellen

    2009-05-31

    The Vermont Biofuels initiative (VBI) is the Vermont Sustainable Jobs Fund's (VSJF) biomass-to-biofuels market development program. Vermont is a small state with a large petroleum dependency for transportation (18th in per capita petroleum consumption) and home heating (55% of all households use petroleum for heating). The VBI marks the first strategic effort to reduce Vermont's dependency on petroleum through the development of homegrown alternatives. As such, it supports the four key priorities of the U.S. Department of Energy's Multi-year Biomass Plan: 1.) Dramatically reduce dependence on foreign oil; 2.) Promote the use of diverse, domestic and sustainable energy resources; 3.) Reduce carbon emissions from energy production and consumption; 4.) Establish a domestic bioindustry. In 2005 VSJF was awarded with a $496,000 Congressionally directed award from U.S. Senator Patrick Leahy. This award was administered through the U.S. Department of Energy (DE-FG36- 05GO85017, hereafter referred to as DOE FY05) with $396,000 to be used by VSJF for biodiesel development and $100,000 to be used by the Vermont Department of Public Service for methane biodigester projects. The intent and strategic focus of the VBI is similar to another DOE funded organization-the Biofuels Center of North Carolina-in that it is a nonprofit driven, statewide biofuels market development effort. DOE FY05 funds were expensed from 2006 through 2008 for seven projects: 1) a feedstock production, logistics, and biomass conversion research project conducted by the University of Vermont Extension; 2) technical assistance in the form of a safety review and engineering study of State Line Biofuels existing biodiesel production facility; 3) technical assistance in the form of a safety review and engineering study of Borderview Farm's proposed biodiesel production facility; 4) technology and infrastructure purchases for capacity expansion at Green Technologies, LLC, a waste vegetable biodiesel producer; 5) technical assistance in the form of feasibility studies for AgNorth Biopower LLC's proposed multi-feedstock biodigester; 6) technology and infrastructure purchases for the construction of a "Cow Power" biodigester at Gervais Family Farm; and 7) the education and outreach activities of the Vermont Biofuels Association. DOE FY05 funded research, technical assistance, and education and outreach activities have helped to provide Vermont farmers and entrepreneurs with important feedstock production, feedstock logistics, and biomass conversion information that did not exist prior as we work to develop an instate biodiesel sector. The efficacy of producing oilseed crops in New England is now established: Oilseed crops can grow well in Vermont, and good yields are achievable given improved harvesting equipment and techniques. DOE FY05 funds used for technology and infrastructure development have expanded Vermont's pool of renewable electricity and liquid fuel generation. It is now clear that on-farm energy production provides an opportunity for Vermont farmers and entrepreneurs to reduce on-farm expenditures of feed and fuel while providing for their energy security. Meanwhile they are developing new value-added revenue sources (e.g., locally produced livestock meal), retaining more dollars in the local economy, and reducing greenhouse gas emissions.

  19. High liquid fuel yielding biofuel processes and a roadmap for the future transportation

    NASA Astrophysics Data System (ADS)

    Singh, Navneet R.

    In a fossil-fuel deprived world when crude oil will be scarce and transportation need cannot be met with electricity and transportation liquid fuel must be produced, biomass derived liquid fuels can be a natural replacement. However, the carbon efficiency of the currently known biomass to liquid fuel conversion processes ranges from 35-40%, yielding 90 ethanol gallon equivalents (ege) per ton of biomass. This coupled with the fact that the efficiency at which solar energy is captured by biomass (<1%) is significantly lower than H 2 (10-27%) and electricity (20-42%), implies that sufficient land area is not available to meet the need for the entire transportation sector. To counter this dilemma, a number of processes have been proposed in this work: a hybrid hydrogen-carbon (H2CAR) process based on biomass gasification followed by the Fischer-Tropsch process such that 100% carbon efficiency is achieved yielding 330 ege/ton biomass using hydrogen derived from a carbon-free energy. The hydrogen requirement for the H2CAR process is 0.33 kg/liter of diesel. To decrease the hydrogen requirement associated with the H2CAR process, a hydrogen bio-oil (H2Bioil) process based on biomass fast-hydropyrolysis/hydrodeoxygenation is proposed which can achieve liquid fuel yield of 215 ege/ton consuming 0.11 kg hydrogen per liter of oil. Due to the lower hydrogen consumption of the H2Bioil process, synergistically integrated transition pathways are feasible where hot syngas derived from coal gasification (H2Bioil-C) or a natural gas reformer (H 2Bioil-NG) is used to supply the hydrogen and process heat for the biomass fast-hydropyrolysis/hydrodeoxygenation. Another off-shoot of the H2Bioil process is the H2Bioil-B process, where hydrogen required for the hydropyrolysis is obtained from gasification of a fraction of the biomass. H2Bioil-B achieves the highest liquid fuel yield (126-146 ege/ton of biomass) reported in the literature for any self-contained conversion of biomass to biofuel. Finally, an integration of the H2Bioil process with the H2CAR process is suggested which can achieve 100% carbon efficiency (330 ege/ton of biomass) at the expense of 0.24 kg hydrogen/liter of oil. A sun-to-fuel efficiency analysis shows that extracting CO2 from air and converting it to liquid fuel is at least two times more efficient than growing dedicated fuel crops and converting them to liquid fuel even for the highest biomass growth rates feasible by algae. This implies that liquid fuel should preferably be produced from sustainably available waste (SAW) biomass first and if the SAW biomass is unable to meet the demand for liquid fuel, then, CO2 should be extracted from air and converted to liquid fuel, rather than growing biomass. Furthermore, based on the Sun-to-Wheels recovery for different transportation pathways, synergistic and complementary use of electricity, hydrogen and biomass, all derived from solar energy, is presented in an energy efficient roadmap to successfully propel the entire future transportation sector.

  20. Green chemistry, biofuels, and biorefinery.

    PubMed

    Clark, James H; Luque, Rafael; Matharu, Avtar S

    2012-01-01

    In the current climate of several interrelated impending global crises, namely, climate change, chemicals, energy, and oil, the impact of green chemistry with respect to chemicals and biofuels generated from within a holistic concept of a biorefinery is discussed. Green chemistry provides unique opportunities for innovation via product substitution, new feedstock generation, catalysis in aqueous media, utilization of microwaves, and scope for alternative or natural solvents. The potential of utilizing waste as a new resource and the development of integrated facilities producing multiple products from biomass is discussed under the guise of biorefineries. Biofuels are discussed in depth, as they not only provide fuel (energy) but are also a source of feedstock chemicals. In the future, the commercial success of biofuels commensurate with consumer demand will depend on the availability of new green (bio)chemical technologies capable of converting waste biomass to fuel in a context of a biorefinery. PMID:22468603

  1. Biofuel production from crude palm oil with supercritical alcohols: comparative LCA studies.

    PubMed

    Sawangkeaw, Ruengwit; Teeravitud, Sunsanee; Piumsomboon, Pornpote; Ngamprasertsith, Somkiat

    2012-09-01

    A recent life cycle assessment (LCA) reported that biodiesel production in supercritical alcohols (SCA) produces a higher environmental load than the homogeneous catalytic process because an enormous amount of energy is required to recover excess alcohol. However, the excess alcohol could be dramatically reduced by increasing the operating temperature to 400°C; although the product would have to be considered as an alternative biofuel instead of biodiesel. A comparative LCA of the biodiesel production in two SCA at 300°C (C-SCA) and novel biofuel production in the same two SCA at 400°C (N-SCA) is presented. It was clear that the N-SCA process produces a dramatically reduced environmental load over that of the C-SCA process due to a lower amount of excess alcohol being used. The N-SCA process could be improved in terms of its environmental impact by changing from fossil fuel to biomass-based fuels for the steam generation. PMID:22776259

  2. Quantifying the climate impacts of albedo changes due to biofuel production: a comparison with biogeochemical effects

    NASA Astrophysics Data System (ADS)

    Caiazzo, Fabio; Malina, Robert; Staples, Mark D.; Wolfe, Philip J.; Yim, Steve H. L.; Barrett, Steven R. H.

    2014-01-01

    Lifecycle analysis is a tool widely used to evaluate the climate impact of greenhouse gas emissions attributable to the production and use of biofuels. In this paper we employ an augmented lifecycle framework that includes climate impacts from changes in surface albedo due to land use change. We consider eleven land-use change scenarios for the cultivation of biomass for middle distillate fuel production, and compare our results to previous estimates of lifecycle greenhouse gas emissions for the same set of land-use change scenarios in terms of CO2e per unit of fuel energy. We find that two of the land-use change scenarios considered demonstrate a warming effect due to changes in surface albedo, compared to conventional fuel, the largest of which is for replacement of desert land with salicornia cultivation. This corresponds to 222 gCO2e/MJ, equivalent to 3890% and 247% of the lifecycle GHG emissions of fuels derived from salicornia and crude oil, respectively. Nine of the land-use change scenarios considered demonstrate a cooling effect, the largest of which is for the replacement of tropical rainforests with soybean cultivation. This corresponds to - 161 gCO2e/MJ, or - 28% and - 178% of the lifecycle greenhouse gas emissions of fuels derived from soybean and crude oil, respectively. These results indicate that changes in surface albedo have the potential to dominate the climate impact of biofuels, and we conclude that accounting for changes in surface albedo is necessary for a complete assessment of the aggregate climate impacts of biofuel production and use.

  3. Catalytic processes towards the production of biofuels in a palm oil and oil palm biomass-based biorefinery.

    PubMed

    Chew, Thiam Leng; Bhatia, Subhash

    2008-11-01

    In Malaysia, there has been interest in the utilization of palm oil and oil palm biomass for the production of environmental friendly biofuels. A biorefinery based on palm oil and oil palm biomass for the production of biofuels has been proposed. The catalytic technology plays major role in the different processing stages in a biorefinery for the production of liquid as well as gaseous biofuels. There are number of challenges to find suitable catalytic technology to be used in a typical biorefinery. These challenges include (1) economic barriers, (2) catalysts that facilitate highly selective conversion of substrate to desired products and (3) the issues related to design, operation and control of catalytic reactor. Therefore, the catalytic technology is one of the critical factors that control the successful operation of biorefinery. There are number of catalytic processes in a biorefinery which convert the renewable feedstocks into the desired biofuels. These include biodiesel production from palm oil, catalytic cracking of palm oil for the production of biofuels, the production of hydrogen as well as syngas from biomass gasification, Fischer-Tropsch synthesis (FTS) for the conversion of syngas into liquid fuels and upgrading of liquid/gas fuels obtained from liquefaction/pyrolysis of biomass. The selection of catalysts for these processes is essential in determining the product distribution (olefins, paraffins and oxygenated products). The integration of catalytic technology with compatible separation processes is a key challenge for biorefinery operation from the economic point of view. This paper focuses on different types of catalysts and their role in the catalytic processes for the production of biofuels in a typical palm oil and oil palm biomass-based biorefinery. PMID:18434141

  4. Possible future effects of large-scale algae cultivation for biofuels on coastal eutrophication in Europe.

    PubMed

    Blaas, Harry; Kroeze, Carolien

    2014-10-15

    Biodiesel is increasingly considered as an alternative for fossil diesel. Biodiesel can be produced from rapeseed, palm, sunflower, soybean and algae. In this study, the consequences of large-scale production of biodiesel from micro-algae for eutrophication in four large European seas are analysed. To this end, scenarios for the year 2050 are analysed, assuming that in the 27 countries of the European Union fossil diesel will be replaced by biodiesel from algae. Estimates are made for the required fertiliser inputs to algae parks, and how this may increase concentrations of nitrogen and phosphorus in coastal waters, potentially leading to eutrophication. The Global NEWS (Nutrient Export from WaterSheds) model has been used to estimate the transport of nitrogen and phosphorus to the European coastal waters. The results indicate that the amount of nitrogen and phosphorus in the coastal waters may increase considerably in the future as a result of large-scale production of algae for the production of biodiesel, even in scenarios assuming effective waste water treatment and recycling of waste water in algae production. To ensure sustainable production of biodiesel from micro-algae, it is important to develop cultivation systems with low nutrient losses to the environment. PMID:25058933

  5. Biofuel feedstocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There are many forms of feedstocks for biofuel production. Animal manures and municipal solid wastes have been used to generate methane for on-farm and municipality energy uses. Fuel ethanol has been produced commercially using plant-derived starch and sugar feedstocks. Technologies for productio...

  6. Versatile microbial surface-display for environmental remediation and biofuels production.

    PubMed

    Wu, Cindy H; Mulchandani, Ashok; Chen, Wilfred

    2008-04-01

    Surface display is a powerful technique that uses natural microbial functional components to express proteins or peptides on the cell exterior. Since the reporting of the first surface-display system in the mid-1980s, a variety of new systems have been reported for yeast, Gram-positive and Gram-negative bacteria. Non-conventional display methods are emerging, eliminating the generation of genetically modified microorganisms. Cells with surface display are used as biocatalysts, biosorbents and biostimulants. Microbial cell-surface display has proven to be extremely important for numerous applications, ranging from combinatorial library screening and protein engineering to bioremediation and biofuels production. PMID:18321708

  7. Biofuels from E. Coli: Engineering E. coli as an Electrofuels Chassis for Isooctane Production

    SciTech Connect

    2010-07-16

    Electrofuels Project: Ginkgo Bioworks is bypassing photosynthesis and engineering E. coli to directly use carbon dioxide (CO2) to produce biofuels. E. coli doesn’t naturally metabolize CO2, but Ginkgo Bioworks is manipulating and incorporating the genes responsible for CO2 metabolism into the microorganism. By genetically modifying E. coli, Ginkgo Bioworks will enhance its rate of CO2 consumption and liquid fuel production. Ginkgo Bioworks is delivering CO2 to E. coli as formic acid, a simple industrial chemical that provides energy and CO2 to the bacterial system.

  8. Versatile microbial surface-display for environmental remediation and biofuels production

    SciTech Connect

    Wu, Cindy H.; Mulchandani, Ashok; Chen, wilfred

    2008-02-14

    Surface display is a powerful technique that utilizes natural microbial functional components to express proteins or peptides on the cell exterior. Since the reporting of the first surface-display system in the mid-1980s, a variety of new systems have been reported for yeast, Gram-positive and Gram-negative bacteria. Non-conventional display methods are emerging, eliminating the generation of genetically modified microorganisms. Cells with surface display are used as biocatalysts, biosorbents and biostimulants. Microbial cell-surface display has proven to be extremely important for numerous applications ranging from combinatorial library screening and protein engineering to bioremediation and biofuels production.

  9. Engineering terpene biosynthesis in Streptomyces for production of the advanced biofuel precursor bisabolene.

    PubMed

    Phelan, Ryan M; Sekurova, Olga N; Keasling, Jay D; Zotchev, Sergey B

    2015-04-17

    The past decade has witnessed a large influx of research toward the creation of sustainable, biologically derived fuels. While significant effort has been exerted to improve production capacity in common hosts, such as Escherichia coli or Saccharomyces cerevisiae, studies concerning alternate microbes comparatively lag. In an effort to expand the breadth of characterized hosts for fuel production, we map the terpene biosynthetic pathway in a model actinobacterium, Streptomyces venezuelae, and further alter secondary metabolism to afford the advanced biofuel precursor bisabolene. Leveraging information gained from study of the native isoprenoid pathway, we were able to increase bisabolene titer nearly 5-fold over the base production strain, more than 2 orders of magnitude greater than the combined terpene yield in the wild-type host. We also explored production on carbon sources of varying complexity to, notably, define this host as one able to perform consolidated bioprocessing. PMID:25006988

  10. Integration of microalgae cultivation with industrial waste remediation for biofuel and bioenergy production: opportunities and limitations.

    PubMed

    McGinn, Patrick J; Dickinson, Kathryn E; Bhatti, Shabana; Frigon, Jean-Claude; Guiot, Serge R; O'Leary, Stephen J B

    2011-09-01

    There is currently a renewed interest in developing microalgae as a source of renewable energy and fuel. Microalgae hold great potential as a source of biomass for the production of energy and fungible liquid transportation fuels. However, the technologies required for large-scale cultivation, processing, and conversion of microalgal biomass to energy products are underdeveloped. Microalgae offer several advantages over traditional 'first-generation' biofuels crops like corn: these include superior biomass productivity, the ability to grow on poor-quality land unsuitable for agriculture, and the potential for sustainable growth by extracting macro- and micronutrients from wastewater and industrial flue-stack emissions. Integrating microalgal cultivation with municipal wastewater treatment and industrial CO(2) emissions from coal-fired power plants is a potential strategy to produce large quantities of biomass, and represents an opportunity to develop, test, and optimize the necessary technologies to make microalgal biofuels more cost-effective and efficient. However, many constraints on the eventual deployment of this technology must be taken into consideration and mitigating strategies developed before large scale microalgal cultivation can become a reality. As a strategy for CO(2) biomitigation from industrial point source emitters, microalgal cultivation can be limited by the availability of land, light, and other nutrients like N and P. Effective removal of N and P from municipal wastewater is limited by the processing capacity of available microalgal cultivation systems. Strategies to mitigate against the constraints are discussed. PMID:21461850

  11. Effects of Escherichia coli on mixotrophic growth of Chlorella minutissima and production of biofuel precursors.

    PubMed

    Higgins, Brendan T; VanderGheynst, Jean S

    2014-01-01

    Chlorella minutissima was co-cultured with Escherichia coli in airlift reactors under mixotrophic conditions (glucose, glycerol, and acetate substrates) to determine possible effects of bacterial contamination on algal biofuel production. It was hypothesized that E. coli would compete with C. minutissima for nutrients, displacing algal biomass. However, C. minutissima grew more rapidly and to higher densities in the presence of E. coli, suggesting a symbiotic relationship between the organisms. At an initial 1% substrate concentration, the co-culture produced 200-587% more algal biomass than the axenic C. minutissima cultures. Co-cultures grown on 1% substrate consumed 23-737% more of the available carbon substrate than the sum of substrate consumed by E. coli and C. minutissima alone. At 1% substrate, total lipid and starch productivity were elevated in co-cultures compared to axenic cultures indicating that bacterial contamination was not detrimental to the production of biofuel precursors in this specific case. Bio-fouling of the reactors observed in co-cultures and acid formation in all mixotrophic cultures, however, could present challenges for scale-up. PMID:24805253

  12. From pandemic preparedness to biofuel production: Tobacco finds its biotechnology niche in North America

    DOE PAGESBeta

    Powell, Joshua D.

    2015-09-25

    As part of my NSD Innovation awarded funds (95470 Powell Innovation: charge code N38540) one my deliverables was a review article for journal submission summarizing my work on this project. My NSD Innovation project is expressing Ebola antibodies in tobacco plants. I've attached abstract below Title: From pandemic preparedness to biofuel production: tobacco finds its biotechnology niche in North America Abstract: Abstract: In 2012 scientists funded by the U.S. Defense Advanced Research Projects Agency (DARPA) produced 10 million doses of influenza vaccine in tobacco in a milestone deadline of one month. Recently the experimental antibody cocktail Zmapp™, also produced inmore » tobacco, has shown promise as an emergency intervention therapeutic against Ebola. These two examples showcase how collaborative efforts between government, private industry and academia are applying plant biotechnology to combat pathogenic agents. Opportunities now exist repurposing tobacco expression systems for exciting new applications in synthetic biology, biofuels production and industrial enzyme production. Lastly, as plant-produced biotherapeutics become more mainstream, government funding agencies need to be cognizant of the idea that many plant-produced biologicals are often safer, cheaper and just as efficacious as their counterparts that are produced using traditional expression systems.« less

  13. Effects of Escherichia coli on Mixotrophic Growth of Chlorella minutissima and Production of Biofuel Precursors

    PubMed Central

    Higgins, Brendan T.; VanderGheynst, Jean S.

    2014-01-01

    Chlorella minutissima was co-cultured with Escherichia coli in airlift reactors under mixotrophic conditions (glucose, glycerol, and acetate substrates) to determine possible effects of bacterial contamination on algal biofuel production. It was hypothesized that E. coli would compete with C. minutissima for nutrients, displacing algal biomass. However, C. minutissima grew more rapidly and to higher densities in the presence of E. coli, suggesting a symbiotic relationship between the organisms. At an initial 1% substrate concentration, the co-culture produced 200-587% more algal biomass than the axenic C. minutissima cultures. Co-cultures grown on 1% substrate consumed 23–737% more of the available carbon substrate than the sum of substrate consumed by E. coli and C. minutissima alone. At 1% substrate, total lipid and starch productivity were elevated in co-cultures compared to axenic cultures indicating that bacterial contamination was not detrimental to the production of biofuel precursors in this specific case. Bio-fouling of the reactors observed in co-cultures and acid formation in all mixotrophic cultures, however, could present challenges for scale-up. PMID:24805253

  14. From Pandemic Preparedness to Biofuel Production: Tobacco Finds Its Biotechnology Niche in North America

    SciTech Connect

    Powell, Joshua D.

    2015-09-25

    As part of my NSD Innovation awarded funds (95470 Powell Innovation: charge code N38540) one my deliverables was a review article for journal submission summarizing my work on this project. My NSD Innovation project is expressing Ebola antibodies in tobacco plants. I've attached abstract below Title: From pandemic preparedness to biofuel production: tobacco finds its biotechnology niche in North America Abstract: Abstract: In 2012 scientists funded by the U.S. Defense Advanced Research Projects Agency (DARPA) produced 10 million doses of influenza vaccine in tobacco in a milestone deadline of one month. Recently the experimental antibody cocktail Zmapp™, also produced in tobacco, has shown promise as an emergency intervention therapeutic against Ebola. These two examples showcase how collaborative efforts between government, private industry and academia are applying plant biotechnology to combat pathogenic agents. Opportunities now exist repurposing tobacco expression systems for exciting new applications in synthetic biology, biofuels production and industrial enzyme production. As plant-produced biotherapeutics become more mainstream, government funding agencies need to be cognizant of the idea that many plant-produced biologicals are often safer, cheaper and just as efficacious as their counterparts that are produced using traditional expression systems.

  15. From pandemic preparedness to biofuel production: Tobacco finds its biotechnology niche in North America

    SciTech Connect

    Powell, Joshua D.

    2015-09-25

    As part of my NSD Innovation awarded funds (95470 Powell Innovation: charge code N38540) one my deliverables was a review article for journal submission summarizing my work on this project. My NSD Innovation project is expressing Ebola antibodies in tobacco plants. I've attached abstract below Title: From pandemic preparedness to biofuel production: tobacco finds its biotechnology niche in North America Abstract: Abstract: In 2012 scientists funded by the U.S. Defense Advanced Research Projects Agency (DARPA) produced 10 million doses of influenza vaccine in tobacco in a milestone deadline of one month. Recently the experimental antibody cocktail Zmapp™, also produced in tobacco, has shown promise as an emergency intervention therapeutic against Ebola. These two examples showcase how collaborative efforts between government, private industry and academia are applying plant biotechnology to combat pathogenic agents. Opportunities now exist repurposing tobacco expression systems for exciting new applications in synthetic biology, biofuels production and industrial enzyme production. Lastly, as plant-produced biotherapeutics become more mainstream, government funding agencies need to be cognizant of the idea that many plant-produced biologicals are often safer, cheaper and just as efficacious as their counterparts that are produced using traditional expression systems.

  16. Fuel from Tobacco and Arundo Donax: Synthetic Crop for Direct Drop-in Biofuel Production through Re-routing the Photorespiration Intermediates and Engineering Terpenoid Pathways

    SciTech Connect

    2012-02-15

    PETRO Project: Biofuels offer renewable alternatives to petroleum-based fuels that reduce net greenhouse gas emissions to nearly zero. However, traditional biofuels production is limited not only by the small amount of solar energy that plants convert through photosynthesis into biological materials, but also by inefficient processes for converting these biological materials into fuels. Farm-ready, non-food crops are needed that produce fuels or fuel-like precursors at significantly lower costs with significantly higher productivity. To make biofuels cost-competitive with petroleum-based fuels, biofuels production costs must be cut in half.

  17. Production of algal-based biofuel using non-fresh water sources.

    SciTech Connect

    Sun, Amy Cha-Tien; Reno, Marissa Devan

    2007-09-01

    The goal of this LDRD involves development of a system dynamics model to understand the interdependencies between water resource availability and water needs for production of biofuels. Specifically, this model focuses on availability and feasibility of non-traditional water sources from dairy wastewater, produced water from crude oil production and from coal-bed methane gas extraction for the production of algal-based biofuel. The conceptual simulation framework and historical data are based on two locales within New Mexico, the San Juan basin in the northwest and the Permian basin in the southeast, where oil and gas drilling have increased considerably in the last ten years. The overall water balance ignores both transportation options and water chemistry and is broken down by county level. The resulting model contains an algal growth module, a dairy module, an oil production module, and a gas production module. A user interface is also created for controlling the adjustable parameters in the model. Our preliminary investigation indicates a cyclical demand for non-fresh water due to the cyclical nature of algal biomass production and crop evapotranspiration. The wastewater from the dairy industry is not a feasible non-fresh water source because the agricultural water demand for cow's dry feed far exceeds the amount generated at the dairy. The uncertainty associated with the water demand for cow's dry matter intake is the greatest in this model. The oil- and gas-produced water, ignoring the quality, provides ample supply for water demand in algal biomass production. There remains work to address technical challenges associated with coupling the appropriate non-fresh water source to the local demand.

  18. Combining micro-structures and micro-algae to increase lipid production for bio-fuel

    NASA Astrophysics Data System (ADS)

    Vyawahare, Saurabh; Zhu, Emilly; Mestler, Troy; Estévez-Torres, André.; Austin, Robert

    2011-03-01

    3rd generation bio-fuels like lipid producing micro-algae are a promising source of energy that could replace our dependence on petroleum. However, until there are improvements in algae oil yields, and a reduction in the energy needed for processing, algae bio-fuels are not economically competitive with petroleum. Here, we describe our work combining micro-fabricated devices with micro-algae Neochloris oleoabundans, a species first isolated on the sand dunes of Saudi Arabia. Inserting micro-algae of varying fitness into a landscape of micro-habitats allows us to evolve and select them based on a variety of conditions like specific gravity, starvation response and Nile Red fluorescence (which is a marker for lipid production). Hence, we can both estimate the production of lipids and generate conditions that allow the creation and isolation of algae which produce higher amounts of lipids, while discarding the rest. Finally, we can use micro-fabricated structures and flocculation to de-water these high lipid producing algae, reducing the need for expensive centrifugation and filtration.

  19. Simulated moving bed separation of agarose-hydrolyzate components for biofuel production from marine biomass.

    PubMed

    Kim, Pung-Ho; Nam, Hee-Geun; Park, Chanhun; Wang, Nien-Hwa Linda; Chang, Yong Keun; Mun, Sungyong

    2015-08-01

    The economically-efficient separation of galactose, levulinic acid (LA), and 5-hydroxymethylfurfural (5-HMF) in acid hydrolyzate of agarose has been a key issue in the area of biofuel production from marine biomass. To address this issue, an optimal simulated moving bed (SMB) process for continuous separation of the three agarose-hydrolyzate components with high purities, high yields, and high throughput was developed in this study. As a first step for this task, the adsorption isotherm and mass-transfer parameters of each component on the qualified adsorbent were determined through a series of multiple frontal experiments. The determined parameters were then used in optimizing the SMB process for the considered separation. Finally, the optimized SMB process was tested experimentally using a self-assembled SMB unit with four zones. The SMB experimental results and the relevant computer simulations verified that the developed process in this study was quite successful in the economically-efficient separation of galactose, LA, and 5-HMF in a continuous mode with high purities and high yields. It is thus expected that the developed SMB process in this study will be able to serve as one of the trustworthy ways of improving the economic feasibility of biofuel production from marine biomass. PMID:26141276

  20. Comparative genomics of xylose-fermenting fungi for enhanced biofuel production

    SciTech Connect

    Wohlbach, Dana J.; Kuo, Alan; Sato, Trey K.; Potts, Katlyn M.; Salamov, Asaf A.; LaButti, Kurt M.; Sun, Hui; Clum, Alicia; Pangilinan, Jasmyn L.; Lindquist, Erika A.; Lucas, Susan; Lapidus, Alla; Jin, Mingjie; Gunawan, Christa; Balan, Venkatesh; Dale, Bruce E.; Jeffries, Thomas W.; Zinkel, Robert; Barry, Kerrie W.; Grigoriev, Igor V.; Gasch, Audrey P.

    2011-02-24

    Cellulosic biomass is an abundant and underused substrate for biofuel production. The inability of many microbes to metabolize the pentose sugars abundant within hemicellulose creates specific challenges for microbial biofuel production from cellulosic material. Although engineered strains of Saccharomyces cerevisiae can use the pentose xylose, the fermentative capacity pales in comparison with glucose, limiting the economic feasibility of industrial fermentations. To better understand xylose utilization for subsequent microbial engineering, we sequenced the genomes of two xylose-fermenting, beetle-associated fungi, Spathaspora passalidarum and Candida tenuis. To identify genes involved in xylose metabolism, we applied a comparative genomic approach across 14 Ascomycete genomes, mapping phenotypes and genotypes onto the fungal phylogeny, and measured genomic expression across five Hemiascomycete species with different xylose-consumption phenotypes. This approach implicated many genes and processes involved in xylose assimilation. Several of these genes significantly improved xylose utilization when engineered into S. cerevisiae, demonstrating the power of comparative methods in rapidly identifying genes for biomass conversion while reflecting on fungal ecology.

  1. Hydrocracking of vacuum gas oil-vegetable oil mixtures for biofuels production.

    PubMed

    Bezergianni, Stella; Kalogianni, Aggeliki; Vasalos, Iacovos A

    2009-06-01

    Hydrocracking of vacuum gas oil (VGO)--vegetable oil mixtures is a prominent process for the production of biofuels. In this work both pre-hydrotreated and non-hydrotreated VGO are assessed whether they are suitable fossil components in a VGO-vegetable oil mixture as feed-stocks to a hydrocracking process. This assessment indicates the necessity of a VGO pre-hydrotreated step prior to hydrocracking the VGO-vegetable oil mixture. Moreover, the comparison of two different mixing ratios suggests that higher vegetable oil content favors hydrocracking product yields and qualities. Three commercial catalysts of different activity are utilized in order to identify a range of products that can be produced via a hydrocracking route. Finally, the effect of temperature on hydrocracking VGO-vegetable oil mixtures is studied in terms of conversion and selectivity to diesel, jet/kerosene and naphtha. PMID:19231171

  2. Classification, mode of action and production strategy of xylanase and its application for biofuel production from water hyacinth.

    PubMed

    Uday, Uma Shankar Prasad; Choudhury, Payel; Bandyopadhyay, Tarun Kanti; Bhunia, Biswanath

    2016-01-01

    Xylanases are classified under glycoside hydrolase families which represent one of the largest groups of commercial enzymes. Depolymerizing xylan molecules into monomeric pentose units involves the synergistic action of mainly two key enzymes which are endo-β-xylanase and β-xylosidase. Xylanases are different with respect to their mode of action, substrate specificities, biochemical properties, 3D structure and are widely produced by a spectrum of bacteria and fungi. Currently, large scale production of xylanase can be produced through the application of genetic engineering tool which allow fast identification of novel xylanase genes and their genetic variations makes it an ideal enzymes. Due to depletion of fossil fuel, there is urgent need to find out environment friendly and sustainable energy sources. Therefore, utilisation of cheap lignocellulosic materials along with proper optimisation of process is most important for cost efficient ethanol production. Among, various types of lignocellulosic substances, water hyacinth, a noxious aquatic weed, has been found in many tropical. Therefore, the technological development for biofuel production from water hyacinth is becoming commercially worthwhile. In this review, the classification and mode of action of xylanase including genetic regulation and strategy for robust xylanase production have been critically discussed from recent reports. In addition various strategies for cost effective biofuel production from water hyacinth including chimeric proteins design has also been critically evaluated. PMID:26529189

  3. Relative Impacts of Climate and Land Surface Changes on Hydrology in the US Midwest: Implications for Biofuel Production

    NASA Astrophysics Data System (ADS)

    Xu, X.; Scanlon, B. R.; Schilling, K.

    2012-12-01

    There is considerable interest in biofuel production in the US Midwest; however, potential adverse impacts on water resources are a concern. This study explores relationships between hydrologic change and climate and land surface changes, based on long-term (1930s-2010) monitoring datasets of 45 stream gage stations. Sensitivity of streamflow and baseflow to climate was evaluated using an empirical climate elasticity approach and residuals were attributed to land surface changes. Results show significant increases in streamflow (2.1±0.3 mm/yr) in 24% of stations, increases in baseflow (0.7±0.3 mm/yr) in 60% of stations, and in baseflow index (0.2±0.1%/yr) in 44% of stations. Although climate variability and land surface changes contributed equally to streamflow changes, land surface changes contributed about three times more than climate variability to baseflow and seven times more to baseflow index. Watersheds (~50%) with no significant climate change but with significant flow change provide direct evidence that land surface changes in the Midwest, including crop types, tillage, tiling etc, produced significant impacts on hydrologic processes. Limiting analysis to these watersheds shows that ratios of land surface changes to climate variability was a factor of three for streamflow, 4.6 for baseflow, and 13.5 for baseflow index. These changes in flow have generally been accompanied by degradation of water quality. Because past changes in crop types have been dominated by perennial crops to annual (corn and soybeans) crops, reversal to more perennial grasses for second generation biofuels should reduce flow, particularly baseflow in the future, with consequent improvements in water quality.

  4. Water Resources Implications of Cellulosic Biofuel Production at a Regional Scale

    NASA Astrophysics Data System (ADS)

    Christopher, S. F.; Schoenholtz, S. H.; Nettles, J. E.

    2011-12-01

    Recent increases in oil prices, a strong national interest in greater energy independence, and a concern for the role of fossil fuels in global climate change, have led to a dramatic expansion in use of alternative renewable energy sources in the U.S. The U.S. government has mandated production of 36 billion gallons of renewable fuels by 2022, of which 16 billion gallons are required to be cellulosic biofuels. Production of cellulosic biomass offers a promising alternative to corn-based systems because large-scale production of corn-based ethanol often requires irrigation and is associated with increased erosion, excess sediment export, and enhanced leaching of nitrogen and phosphorus. Although cultivation of switchgrass using standard agricultural practices is one option being considered for production of cellulosic biomass, intercropping cellulosic biofuel crops within managed forests could provide feedstock without primary land use change or the water quality impacts associated with annual crops. Catchlight Energy LLC is examining the feasibility and sustainability of intercropping switchgrass in loblolly pine plantations in the southeastern U.S. Ongoing research is determining efficient operational techniques and information needed to evaluate effects of these practices on water resources in small watershed-scale (~25 ha) studies. Three sets of four to five sub-watersheds are fully instrumented and currently collecting calibration data in North Carolina, Alabama, and Mississippi. These watershed studies will provide detailed information to understand processes and guide management decisions. However, environmental implications of cellulosic systems need to be examined at a regional scale. We used the Soil Water Assessment Tool (SWAT), a physically-based hydrologic model, to examine water quantity effects of various land use change scenarios ranging from switchgrass intercropping a small percentage of managed pine forest land to conversion of all managed forested land to switchgrass. The regional-scale SWAT model was successfully run and calibrated on the ~ 5 million ha Tombigbee Watershed located in Mississippi and Alabama. Publically available datasets were used as input to the model and for calibration. To improve calibration statistics, five tree age classes (0-4 yr, 4-10 yr, 10-17 yr, 17-24 yr, 24-30 yr) were added to the model to more appropriately represent existing forested systems in the region, which are not included within the standard SWAT set-up. Our results will be essential to public policy makers as they influence and plan for large-scale production of cellulosic biofuels, while sustaining water quality and quantity.

  5. Emerging strategies of lignin engineering and degradation for cellulosic biofuel production.

    PubMed

    Weng, Jing-Ke; Li, Xu; Bonawitz, Nicholas D; Chapple, Clint

    2008-04-01

    Ethanol and other biofuels produced from lignocellulosic biomass represent a renewable, more carbon-balanced alternative to both fossil fuels and corn-derived or sugarcane-derived ethanol. Unfortunately, the presence of lignin in plant cell walls impedes the breakdown of cell wall polysaccharides to simple sugars and the subsequent conversion of these sugars to usable fuel. Recent advances in the understanding of lignin composition, polymerization, and regulation have revealed new opportunities for the rational manipulation of lignin in future bioenergy crops, augmenting the previous successful approach of manipulating lignin monomer biosynthesis. Furthermore, recent studies on lignin degradation in nature may provide novel resources for the delignification of dedicated bioenergy crops and other sources of lignocellulosic biomass. PMID:18403196

  6. A state of the art of metabolic networks of unicellular microalgae and cyanobacteria for biofuel production.

    PubMed

    Baroukh, Caroline; Muñoz-Tamayo, Rafael; Steyer, Jean-Philippe; Bernard, Olivier

    2015-07-01

    The most promising and yet challenging application of microalgae and cyanobacteria is the production of renewable energy: biodiesel from microalgae triacylglycerols and bioethanol from cyanobacteria carbohydrates. A thorough understanding of microalgal and cyanobacterial metabolism is necessary to master and optimize biofuel production yields. To this end, systems biology and metabolic modeling have proven to be very efficient tools if supported by an accurate knowledge of the metabolic network. However, unlike heterotrophic microorganisms that utilize the same substrate for energy and as carbon source, microalgae and cyanobacteria require light for energy and inorganic carbon (CO2 or bicarbonate) as carbon source. This double specificity, together with the complex mechanisms of light capture, makes the representation of metabolic network nonstandard. Here, we review the existing metabolic networks of photoautotrophic microalgae and cyanobacteria. We highlight how these networks have been useful for gaining insight on photoautotrophic metabolism. PMID:25916794

  7. Novel approaches to microalgal and cyanobacterial cultivation for bioenergy and biofuel production.

    PubMed

    Heimann, Kirsten

    2016-04-01

    Growing demand for energy and food by the global population mandates finding water-efficient renewable resources. Microalgae/cyanobacteria have shown demonstrated capacity to contribute to global energy and food security. Yet, despite proven process technology and established net energy-effectiveness and cost-effectiveness through co-product generation, microalgal biofuels are not a reality. This review outlines novel biofilm cultivation strategies that are water-smart, the opportunity for direct energy conversion via anaerobic digestion of N2-fixing cyanobacterial biomass and integrative strategies for microalgal biodiesel and/or biocrude production via supercritical methanol-direct transesterification and hydrothermal liquefaction, respectively. Additionally, fermentation of cyanobacterial biofilms could supply bioethanol to feed wet transesterification to biodiesel conversion for on-site use in remote locations. PMID:26953746

  8. Production of Biofuel from Waste Lignocellulosic Biomass Materials Based on Energy Saving Viewpoint

    NASA Astrophysics Data System (ADS)

    Takano, Maki; Hoshino, Kazuhiro

    To develop biofuel production from waste lignocellulosic biomass materials the rice straw was selected one of renewable material and the degradation condition about pretreatment and enzymatic hydrolysis to obtain effectively fermentable sugars was investigated. Rice straw was pretreated by five kinds of methods and then the components ratio of rice straw was examined. First, the steam explosion was selected based on the degradability and the requirement energy. In addition, the best suitable combination of two cellulases to effective and economical hydrolyze was determined from the degradability of these pretreated rice straws. In the simultaneous saccharification and fermentation of the steam explosion rice straw by combining cellulase cocktail and a novel fermenting fungus, 13.2 g/L ethanol was able to product for 96 h.

  9. Genetic engineering of energy crops: a strategy for biofuel production in China.

    PubMed

    Xie, Guosheng; Peng, Liangcai

    2011-02-01

    Biomass utilization is increasingly considered as a practical way for sustainable energy supply and long-term environment care around the world. In concerns with food security in China, starch or sugar-based bioethanol and edible-oil-derived biodiesel are harshly restricted for large scale production. However, conversion of lignocellulosic residues from food crops is a potential alternative. Because of its recalcitrance, current biomass process is unacceptably expensive, but genetic breeding of energy crops is a promising solution. To meet the need, energy crops are defined with a high yield for both food and biofuel purposes. In this review, main grasses (rice, wheat, maize, sorghum and miscanthus) are evaluated for high biomass production, the principles are discussed on modification of plant cell walls that lead to efficient biomass degradation and conversion, and the related biotechnologies are proposed in terms of energy crop selection. PMID:21205188

  10. Fatty Acid-Derived Biofuels and Chemicals Production in Saccharomyces cerevisiae.

    PubMed

    Zhou, Yongjin J; Buijs, Nicolaas A; Siewers, Verena; Nielsen, Jens

    2014-01-01

    Volatile energy costs and environmental concerns have spurred interest in the development of alternative, renewable, sustainable, and cost-effective energy resources. Environment-friendly processes involving microbes can be used to synthesize advanced biofuels. These fuels have the potential to replace fossil fuels in supporting high-power demanding machinery such as aircrafts and trucks. From an engineering perspective, the pathway for fatty acid biosynthesis is an attractive route for the production of advanced fuels such as fatty acid ethyl esters, fatty alcohols, and alkanes. The robustness and excellent accessibility to molecular genetics make the yeast Saccharomyces cerevisiae a suitable host for the purpose of bio-manufacturing. Recent advances in metabolic engineering, as well as systems and synthetic biology, have now provided the opportunity to engineer yeast metabolism for the production of fatty acid-derived fuels and chemicals. PMID:25225637

  11. Fatty Acid-Derived Biofuels and Chemicals Production in Saccharomyces cerevisiae

    PubMed Central

    Zhou, Yongjin J.; Buijs, Nicolaas A.; Siewers, Verena; Nielsen, Jens

    2014-01-01

    Volatile energy costs and environmental concerns have spurred interest in the development of alternative, renewable, sustainable, and cost-effective energy resources. Environment-friendly processes involving microbes can be used to synthesize advanced biofuels. These fuels have the potential to replace fossil fuels in supporting high-power demanding machinery such as aircrafts and trucks. From an engineering perspective, the pathway for fatty acid biosynthesis is an attractive route for the production of advanced fuels such as fatty acid ethyl esters, fatty alcohols, and alkanes. The robustness and excellent accessibility to molecular genetics make the yeast Saccharomyces cerevisiae a suitable host for the purpose of bio-manufacturing. Recent advances in metabolic engineering, as well as systems and synthetic biology, have now provided the opportunity to engineer yeast metabolism for the production of fatty acid-derived fuels and chemicals. PMID:25225637

  12. Biomass logistics analysis for large scale biofuel production: case study of loblolly pine and switchgrass.

    PubMed

    Lu, Xiaoming; Withers, Mitch R; Seifkar, Navid; Field, Randall P; Barrett, Steven R H; Herzog, Howard J

    2015-05-01

    The objective of this study was to assess the costs, energy consumption and greenhouse gas (GHG) emissions throughout the biomass supply chain for large scale biofuel production. Two types of energy crop were considered, switchgrass and loblolly pine, as representative of herbaceous and woody biomass. A biomass logistics model has been developed to estimate the feedstock supply system from biomass production through transportation. Biomass in the form of woodchip, bale and pellet was investigated with road, railway and waterway transportation options. Our analysis indicated that the farm or forest gate cost is lowest for loblolly pine whole tree woodchip at $39.7/dry tonne and highest for switchgrass round bale at $72.3/dry tonne. Switchgrass farm gate GHG emissions is approximately 146kgCO2e/dry tonne, about 4 times higher than loblolly pine. The optimum biomass transportation mode and delivered form are determined by the tradeoff between fixed and variable costs for feedstock shipment. PMID:25710677

  13. Comparison of various microalgae liquid biofuel production pathways based on energetic, economic and environmental criteria.

    PubMed

    Delrue, F; Li-Beisson, Y; Setier, P-A; Sahut, C; Roubaud, A; Froment, A-K; Peltier, G

    2013-05-01

    In view of the increasing demand for bioenergy, in this study, the techno-economic viabilities for three emerging pathways to microalgal biofuel production have been evaluated. The three processes evaluated are the hydrothermal liquefaction (HTL), oil secretion and alkane secretion. These three routes differ in their lipid extraction procedure and the end-products produced. This analysis showed that these three processes showed various advantages: possibility to convert the defatted microalgae into bio-crude via HTL thus increasing the total biodiesel yield; better energetic and environmental performance for oil secretion and an even increased net energy ratio (NER) for alkane secretion. However, great technological breakthroughs are needed before planning any scale-up strategy such as continuous wet biomass processing and heat exchange optimization for the HTL pathway and effective and sustainable excretion for both secretion pathways. PMID:23567683

  14. Black liquor fractionation for biofuels production - a techno-economic assessment.

    PubMed

    Mesfun, Sennai; Lundgren, Joakim; Grip, Carl-Erik; Toffolo, Andrea; Nilsson, Rasika Lasanthi Kudahettige; Rova, Ulrika

    2014-08-01

    The hemicelluloses fraction of black liquor is an underutilized resource in many chemical pulp mills. It is possible to extract and separate the lignin and hemicelluloses from the black liquor and use the hemicelluloses for biochemical conversion into biofuels and chemicals. Precipitation of the lignin from the black liquor would consequently decrease the thermal load on the recovery boiler, which is often referred to as a bottleneck for increased pulp production. The objective of this work is to techno-economically evaluate the production of sodium-free lignin as a solid fuel and butanol to be used as fossil gasoline replacement by fractionating black liquor. The hydrolysis and fermentation processes are modeled in Aspen Plus to analyze energy and material balances as well as to evaluate the plant economics. A mathematical model of an existing pulp and paper mill is used to analyze the effects on the energy performance of the mill subprocesses. PMID:24950095

  15. Estimating sugarcane water requirements for biofuel feedstock production in Maui, Hawaii using satellite imagery

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Anderson, R. G.; Wang, D.

    2011-12-01

    Water availability is one of the limiting factors for sustainable production of biofuel crops. A common method for determining crop water requirement is to multiply daily potential evapotranspiration (ETo) calculated from meteorological parameters by a crop coefficient (Kc) to obtain actual crop evapotranspiration (ETc). Generic Kc values are available for many crop types but not for sugarcane in Maui, Hawaii, which grows on a relatively unstudied biennial cycle. In this study, an algorithm is being developed to estimate sugarcane Kc using normalized difference vegetation index (NDVI) derived from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery. A series of ASTER NDVI maps were used to depict canopy development over time or fractional canopy cover (fc) which was measured with a handheld multispectral camera in the fields during satellite overpass days. Canopy cover was correlated with NDVI values. Then the NDVI based canopy cover was used to estimate Kc curves for sugarcane plants. The remotely estimated Kc and ETc values were compared and validated with ground-truth ETc measurements. The approach is a promising tool for large scale estimation of evapotranspiration of sugarcane or other biofuel crops.

  16. Engineering of a novel cellulose-adherent cellulolytic Saccharomyces cerevisiae for cellulosic biofuel production

    PubMed Central

    Liu, Zhuo; Ho, Shih-Hsin; Sasaki, Kengo; den Haan, Riaan; Inokuma, Kentaro; Ogino, Chiaki; van Zyl, Willem H.; Hasunuma, Tomohisa; Kondo, Akihiko

    2016-01-01

    Cellulosic biofuel is the subject of increasing attention. The main obstacle toward its economic feasibility is the recalcitrance of lignocellulose requiring large amount of enzyme to break. Several engineered yeast strains have been developed with cellulolytic activities to reduce the need for enzyme addition, but exhibiting limited effect. Here, we report the successful engineering of a cellulose-adherent Saccharomyces cerevisiae displaying four different synergistic cellulases on the cell surface. The cellulase-displaying yeast strain exhibited clear cell-to-cellulose adhesion and a “tearing” cellulose degradation pattern; the adhesion ability correlated with enhanced surface area and roughness of the target cellulose fibers, resulting in higher hydrolysis efficiency. The engineered yeast directly produced ethanol from rice straw despite a more than 40% decrease in the required enzyme dosage for high-density fermentation. Thus, improved cell-to-cellulose interactions provided a novel strategy for increasing cellulose hydrolysis, suggesting a mechanism for promoting the feasibility of cellulosic biofuel production. PMID:27079382

  17. A Biophysical Modeling Framework for Assessing the Environmental Impact of Biofuel Production

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Izaurradle, C.; Manowitz, D.; West, T. O.; Post, W. M.; Thomson, A. M.; Nichols, J.; Bandaru, V.; Williams, J. R.

    2009-12-01

    Long-term sustainability of a biofuel economy necessitates environmentally friendly biofuel production systems. We describe a biophysical modeling framework developed to understand and quantify the environmental value and impact (e.g. water balance, nutrients balance, carbon balance, and soil quality) of different biomass cropping systems. This modeling framework consists of three major components: 1) a Geographic Information System (GIS) based data processing system, 2) a spatially-explicit biophysical modeling approach, and 3) a user friendly information distribution system. First, we developed a GIS to manage the large amount of geospatial data (e.g. climate, land use, soil, and hydrograhy) and extract input information for the biophysical model. Second, the Environmental Policy Integrated Climate (EPIC) biophysical model is used to predict the impact of various cropping systems and management intensities on productivity, water balance, and biogeochemical variables. Finally, a geo-database is developed to distribute the results of ecosystem service variables (e.g. net primary productivity, soil carbon balance, soil erosion, nitrogen and phosphorus losses, and N2O fluxes) simulated by EPIC for each spatial modeling unit online using PostgreSQL. We applied this framework in a Regional Intensive Management Area (RIMA) of 9 counties in Michigan. A total of 4,833 spatial units with relatively homogeneous biophysical properties were derived using SSURGO, Crop Data Layer, County, and 10-digit watershed boundaries. For each unit, EPIC was executed from 1980 to 2003 under 54 cropping scenarios (eg. corn, switchgrass, and hybrid poplar). The simulation results were compared with historical crop yields from USDA NASS. Spatial mapping of the results show high variability among different cropping scenarios in terms of the simulated ecosystem services variables. Overall, the framework developed in this study enables the incorporation of environmental factors into economic and life-cycle analysis in order to optimize biomass cropping production scenarios.

  18. Energy balance of biofuel production from biological conversion of crude glycerol.

    PubMed

    Zhang, Xiaolei; Yan, Song; Tyagi, Rajeshwar D; Surampalli, Rao Y; Valéro, Jose R

    2016-04-01

    Crude glycerol, a by-product of biodiesel production, has gained significant attention as a carbon source for biofuel production. This study evaluated the energy balance of biodiesel, hydrogen, biogas, and ethanol production from 3.48 million L of crude glycerol (80% w/v). The conversion efficiency (energy output divided by energy invested) was 1.16, 0.22, 0.27, and 0.40 for the production of biodiesel, hydrogen, biogas, and ethanol respectively. It was found that the use of crude glycerol for biodiesel production was an energy gain process, with a positive energy balance and conversion efficiency of greater than 1. The energy balance revealed a net energy gain of 5226 GJ per 1 million kg biodiesel produced. Production of hydrogen, biogas and ethanol from crude glycerol were energy loss processes. Therefore, the conversion of crude glycerol to lipids and subsequently to biodiesel is suggested to be a better option compared to hydrogen, biogas, or ethanol production with respect to energy balance. PMID:26829450

  19. Development of optimal enzymatic and microbial conversion systems for biofuel production

    NASA Astrophysics Data System (ADS)

    Aramrueang, Natthiporn

    The increase in demand for fuels, along with the concerns over the depletion of fossil fuels and the environmental problems associated with the use of the petroleum-based fuels, has driven the exploitation of clean and renewable energy. Through a collaboration project with Mendota Bioenergy LLC to produce advanced biofuel from sugar beet and other locally grown crops in the Central Valley of California through demonstration and commercial-scale biorefineries, the present study focused on the investigation of selected potential biomass as biofuel feedstock and development of bioconversion systems for sustainable biofuel production. For an efficient biomass-to-biofuel conversion process, three important steps, which are central to this research, must be considered: feedstock characterization, enzymatic hydrolysis of the feedstock, and the bioconversion process. The first part of the research focused on the characterization of various lignocellulosic biomass as feedstocks and investigated their potential ethanol yields. Physical characteristics and chemical composition were analyzed for four sugar beet varieties, three melon varieties, tomato, Jose tall wheatgrass, wheat hay, and wheat straw. Melons and tomato are those products discarded by the growers or processors due to poor quality. The mass-based ethanol potential of each feedstock was determined based on the composition. The high sugar-containing feedstocks are sugar beet roots, melons, and tomato, containing 72%, 63%, and 42% average soluble sugars on a dry basis, respectively. Thus, for these crops, the soluble sugars are the main substrate for ethanol production. The potential ethanol yields, on average, for sugar beet roots, melons, and tomato are 591, 526, and 448 L ethanol/metric ton dry basis (d.b.), respectively. Lignocellulosic biomass, including Jose Tall wheatgrass and wheat straw, are composed primarily of cellulose (27-39% d.b.) and hemicellulose (26-30% d.b.). The ethanol yields from these materials can range from 470 to 533 L ethanol/metric ton (d.b.) Sugar beet leaves contain nearly equal amounts of cellulose (13%), hemicellulose (16%), and pectin (17%). The potential ethanol yield of sugar beet leaves is 340 L ethanol/metric ton (d.b.). As remaining unused in great quantities during the production of sugar beet as a sugar and energy crop, sugar beet leaves was studied as a potential feedstock for the production of biofuel and valuable products. The enzymatic hydrolysis of sugar beet leaves was optimized for fermentable sugar production. Optimization of enzyme usage was performed to make the biorefinery process more cost- and energy-effective. In this research, response surface methodology was used to study the effects of enzyme loadings during the hydrolysis of sugar beet leaves at 10% total solids content, using a mix of cellulases, hemicellulases, and pectinases. The effects of enzyme loadings were studied with a five-level rotatable central composite design for maximum conversion of sugar beet leaves to fermentable sugars. The last part of this study investigated biogas production through the anaerobic digestion of microalgae as they have received much attention as another potential biofuel feedstock. Anaerobic digestion of Spirulina ( Arthrospira platensis) was conducted in batch reactors for the study of the kinetics and, in continuous stirred tank reactors (CSTR), for the study of the two important operating parameters: hydraulic retention time (HRT) and organic loading rate (OLR). The kinetics study on methane production from batch experiments shows first order kinetics and a reaction rate constant of 0.382 d-1. The maximum biogas and methane yields for Spirulina are 0.514 L/gVS and 0.360 L CH4/gVS, respectively. The methane content of the biogas is 68%. During the continuous anaerobic digestion in CSTR for OLR in the range of 1.0-4.0 gVS/L/d, biogas and methane yields are in the ranges of 0.276-0.502 L/ gVS and 0.163-0.342 L CH4/gVS, respectively. Methane content is 59-70% of the biogas. Methane yield decreases with an increase in OLR and a decrease in HRT. The maximum methane production is 0.342 L CH4/gVS at OLR of 1.0 gVS/L d and 25d-HRT, achieving 94% of the maximum yield produced by batch digestion. Ammonia inhibition and the accumulation of volatile fatty acids (VFA) were observed at high OLR. According to the results from the continuous digestion of Spirulina, the recommended HRT should be sufficient at least 15d, with the OLRmax of 2.0 gVS/L to prevent ammonia inhibition at higher feed concentrations. The OLR can be increased when the digester is operated at longer HRT since a long HRT provides a more stable operation. A mathematical model, based on the kinetics study from the batch process, was developed for the prediction of methane production during a continuous digestion process, in relation to HRT. Further improvement of the model may have to include the effects of ammonia inhibition and low solids retention time (SRT) to overcome these limitations. (Abstract shortened by UMI.).

  20. Biofuel Feedstock Assessment For Selected Countries

    SciTech Connect

    Kline, Keith L; Oladosu, Gbadebo A; Wolfe, Amy K; Perlack, Robert D; Dale, Virginia H; McMahon, Matthew

    2008-02-01

    Findings from biofuel feedstock production assessments and projections of future supply are presented and discussed. The report aims to improve capabilities to assess the degree to which imported biofuel could contribute to meeting future U.S. targets to reduce dependence on imported oil. The study scope was focused to meet time and resource requirements. A screening process identified Argentina, Brazil, Canada, China, Colombia, India, Mexico, and the Caribbean Basin Initiative (CBI) region for initial analysis, given their likely role in future feedstock supply relevant to U.S. markets. Supply curves for selected feedstocks in these countries are projected for 2012, 2017 and 2027. The supply functions, along with calculations to reflect estimated supplies available for export and/or biofuel production, were provided to DOE for use in a broader energy market allocation study. Potential cellulosic supplies from crop and forestry residues and perennials were also estimated for 2017 and 2027. The analysis identified capacity to potentially double or triple feedstock production by 2017 in some cases. A majority of supply growth is derived from increasing the area cultivated (especially sugarcane in Brazil). This is supplemented by improving yields and farming practices. Most future supplies of corn and wheat are projected to be allocated to food and feed. Larger shares of future supplies of sugarcane, soybean and palm oil production will be available for export or biofuel. National policies are catalyzing investments in biofuel industries to meet targets for fuel blending that generally fall in the 5-10% range. Social and environmental concerns associated with rapid expansion of feedstock production are considered. If the 2017 projected feedstock supply calculated as 'available' for export or biofuel were converted to fuel, it would represent the equivalent of about 38 billion gallons of gasoline. Sugarcane and bagasse dominate the available supply, representing 64% of the total. Among the nations studied, Brazil is the source of about two-thirds of available supplies, followed distantly by Argentina (12%), India and the CBI region.

  1. Biofuel Feedstock Assessment for Selected Countries

    SciTech Connect

    Kline, K.L.; Oladosu, G.A.; Wolfe, A.K.; Perlack, R.D.; Dale, V.H.

    2008-02-18

    Findings from biofuel feedstock production assessments and projections of future supply are presented and discussed. The report aims to improve capabilities to assess the degree to which imported biofuel could contribute to meeting future U.S. targets to reduce dependence on imported oil. The study scope was focused to meet time and resource requirements. A screening process identified Argentina, Brazil, Canada, China, Colombia, India, Mexico, and the Caribbean Basin Initiative (CBI) region for initial analysis, given their likely role in future feedstock supply relevant to U.S. markets. Supply curves for selected feedstocks in these countries are projected for 2012, 2017 and 2027. The supply functions, along with calculations to reflect estimated supplies available for export and/or biofuel production, were provided to DOE for use in a broader energy market allocation study. Potential cellulosic supplies from crop and forestry residues and perennials were also estimated for 2017 and 2027. The analysis identified capacity to potentially double or triple feedstock production by 2017 in some cases. A majority of supply growth is derived from increasing the area cultivated (especially sugarcane in Brazil). This is supplemented by improving yields and farming practices. Most future supplies of corn and wheat are projected to be allocated to food and feed. Larger shares of future supplies of sugarcane, soybean and palm oil production will be available for export or biofuel. National policies are catalyzing investments in biofuel industries to meet targets for fuel blending that generally fall in the 5-10% range. Social and environmental concerns associated with rapid expansion of feedstock production are considered. If the 2017 projected feedstock supply calculated as ‘available’ for export or biofuel were converted to fuel, it would represent the equivalent of about 38 billion gallons of gasoline. Sugarcane and bagasse dominate the available supply, representing 64% of the total. Among the nations studied, Brazil is the source of about two-thirds of available supplies, followed distantly by Argentina (12%), India and the CBI region.

  2. Enhanced characteristics of genetically modified switchgrass (Panicum virgatum L.) for high biofuel production

    PubMed Central

    2013-01-01

    Background Lignocellulosic biomass is one of the most promising renewable and clean energy resources to reduce greenhouse gas emissions and dependence on fossil fuels. However, the resistance to accessibility of sugars embedded in plant cell walls (so-called recalcitrance) is a major barrier to economically viable cellulosic ethanol production. A recent report from the US National Academy of Sciences indicated that, “absent technological breakthroughs”, it was unlikely that the US would meet the congressionally mandated renewable fuel standard of 35 billion gallons of ethanol-equivalent biofuels plus 1 billion gallons of biodiesel by 2022. We here describe the properties of switchgrass (Panicum virgatum) biomass that has been genetically engineered to increase the cellulosic ethanol yield by more than 2-fold. Results We have increased the cellulosic ethanol yield from switchgrass by 2.6-fold through overexpression of the transcription factor PvMYB4. This strategy reduces carbon deposition into lignin and phenolic fermentation inhibitors while maintaining the availability of potentially fermentable soluble sugars and pectic polysaccharides. Detailed biomass characterization analyses revealed that the levels and nature of phenolic acids embedded in the cell-wall, the lignin content and polymer size, lignin internal linkage levels, linkages between lignin and xylans/pectins, and levels of wall-bound fucose are all altered in PvMYB4-OX lines. Genetically engineered PvMYB4-OX switchgrass therefore provides a novel system for further understanding cell wall recalcitrance. Conclusions Our results have demonstrated that overexpression of PvMYB4, a general transcriptional repressor of the phenylpropanoid/lignin biosynthesis pathway, can lead to very high yield ethanol production through dramatic reduction of recalcitrance. MYB4-OX switchgrass is an excellent model system for understanding recalcitrance, and provides new germplasm for developing switchgrass cultivars as biomass feedstocks for biofuel production. PMID:23651942

  3. From first generation biofuels to advanced solar biofuels.

    PubMed

    Aro, Eva-Mari

    2016-01-01

    Roadmaps towards sustainable bioeconomy, including the production of biofuels, in many EU countries mostly rely on biomass use. However, although biomass is renewable, the efficiency of biomass production is too low to be able to fully replace the fossil fuels. The use of land for fuel production also introduces ethical problems in increasing the food price. Harvesting solar energy by the photosynthetic machinery of plants and autotrophic microorganisms is the basis for all biomass production. This paper describes current challenges and possibilities to sustainably increase the biomass production and highlights future technologies to further enhance biofuel production directly from sunlight. The biggest scientific breakthroughs are expected to rely on a new technology called "synthetic biology", which makes engineering of biological systems possible. It will enable direct conversion of solar energy to a fuel from inexhaustible raw materials: sun light, water and CO2. In the future, such solar biofuels are expected to be produced in engineered photosynthetic microorganisms or in completely synthetic living factories. PMID:26667057

  4. Gaining ground in the modeling of land-use change greenhouse gas emissions associated with biofuel production

    NASA Astrophysics Data System (ADS)

    Dunn, J.; Mueller, S.; Kwon, H.; Wang, M.; Wander, M.

    2012-12-01

    Land-use change (LUC) resulting from biofuel feedstock production and the associated greenhouse gas (GHG) emissions are a hotly-debated aspect of biofuels. Certainly, LUC GHG emissions are one of the most uncertain elements in life cycle analyses (LCA) of biofuels. To estimate LUC GHG emissions, two sets of data are necessary. First, information on the amount and type of land that is converted to biofuel feedstock production is required. These data are typically generated through application of computable general equilibrium (CGE) models such as Purdue University's Global Trade Analysis Project (GTAP) model. Second, soil carbon content data for the affected land types is essential. Recently, Argonne National Laboratory's Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) has been updated with CGE modeling results that estimate the amount and type of LUC world-wide from production of ethanol from corn, corn stover, miscanthus, and switchgrass (Mueller et al. 2012). Moreover, we have developed state-specific carbon content data, determined through modeling with CENTURY, for the two most dominant soil types in the conterminous 48 U.S. states (Kwon et al. 2012) to enable finer-resolution results for domestic LUC GHG emissions for these ethanol production scenarios. Of the feedstocks examined, CCLUB estimates that LUC GHG emissions are highest for corn ethanol (9.1 g CO2e/MJ ethanol) and lowest for miscanthus (-12 g CO2e/MJ ethanol). We will present key observations from CCLUB results incorporated into Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy use in Transportation (GREET) model, which is a LCA tool for transportation fuels and advanced vehicle technologies. We will discuss selected issues in this modeling, including the sensitivity of domestic soil carbon emission factors to modeling parameters and assumptions about the fate of harvested wood products. Further, we will discuss efforts to update CCLUB with county-level soil carbon emission factors and updated international soil carbon emission factors. Finally, we will examine data needs for improved LUC GHG calculations in both the modeling of land conversion and soil carbon content. Kwon, H. Y., Wander, M. M., Mueller, S., Dunn, J. B. "Modeling state-level soil carbon emission factors under various scenarios for direct land use change associated with United States biofuel feedstock production." Biomass and Bioenergy. Under Review. Mueller, S., Dunn, J. B., Wang, M. "Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) Users' Manual and Technical Documentation." May 2012. ANL/ESD/12-5. Available at http://greet.es.anl.gov/publication-cclub-manual.

  5. Clash of the Titans: Comparing productivity via radiation use efficiency for two grass giants of the biofuel field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The comparative productivity of switchgrass (Panicum virgatum L.) and Miscanthus (Miscanthus x giganteus) is of critical importance to the biofuel industry. The radiation use efficiency (RUE), when derived in an environment with non-limiting soil water and soil nutrients, provides one metric of re...

  6. Biogeochemical Research Priorities for Sustainable Biofuel and Bioenergy Feedstock Production in the Americas.

    PubMed

    Gollany, Hero T; Titus, Brian D; Scott, D Andrew; Asbjornsen, Heidi; Resh, Sigrid C; Chimner, Rodney A; Kaczmarek, Donald J; Leite, Luiz F C; Ferreira, Ana C C; Rod, Kenton A; Hilbert, Jorge; Galdos, Marcelo V; Cisz, Michelle E

    2015-12-01

    Rapid expansion in biomass production for biofuels and bioenergy in the Americas is increasing demand on the ecosystem resources required to sustain soil and site productivity. We review the current state of knowledge and highlight gaps in research on biogeochemical processes and ecosystem sustainability related to biomass production. Biomass production systems incrementally remove greater quantities of organic matter, which in turn affects soil organic matter and associated carbon and nutrient storage (and hence long-term soil productivity) and off-site impacts. While these consequences have been extensively studied for some crops and sites, the ongoing and impending impacts of biomass removal require management strategies for ensuring that soil properties and functions are sustained for all combinations of crops, soils, sites, climates, and management systems, and that impacts of biomass management (including off-site impacts) are environmentally acceptable. In a changing global environment, knowledge of cumulative impacts will also become increasingly important. Long-term experiments are essential for key crops, soils, and management systems because short-term results do not necessarily reflect long-term impacts, although improved modeling capability may help to predict these impacts. Identification and validation of soil sustainability indicators for both site prescriptions and spatial applications would better inform commercial and policy decisions. In an increasingly inter-related but constrained global context, researchers should engage across inter-disciplinary, inter-agency, and international lines to better ensure the long-term soil productivity across a range of scales, from site to landscape. PMID:26006220

  7. Production of Algal-based Biofuel from Non-fresh Water Sources

    NASA Astrophysics Data System (ADS)

    Sun, A. C.; Reno, M. D.

    2008-12-01

    A system dynamics model is developed to assess the availability and feasibility of non-traditional water sources from dairy wastewater, produced water from crude oil production and from coal-bed methane gas extraction for the production of algal-based biofuel. The conceptual framework is based on two locales within New Mexico, the San Juan basin in the northwest and the Permian basin in the southeast, where oil and gas drilling have increased considerably in the last ten years. The simulation framework contains an algal growth module, a dairy module, an oil production module, and a gas production module. Our preliminary investigation indicates a cyclical demand for non-fresh water due to the cyclical nature of algal biomass production and crop evapotranspiration. The wastewater from the dairy industry is not a feasible non-fresh water source because the agricultural water demand for cow's dry feed far exceeds the amount generated at the dairy. The uncertainty associated with the water demand for cow's dry matter intake is the greatest in this model. The oil and gas produced water, ignoring the quality, provides ample supply for water demand in algal biomass production. There remains work to address technical challenges associated with coupling the appropriate non-fresh water source to the local demand.

  8. Biogeochemical Research Priorities for Sustainable Biofuel and Bioenergy Feedstock Production in the Americas

    NASA Astrophysics Data System (ADS)

    Gollany, Hero T.; Titus, Brian D.; Scott, D. Andrew; Asbjornsen, Heidi; Resh, Sigrid C.; Chimner, Rodney A.; Kaczmarek, Donald J.; Leite, Luiz F. C.; Ferreira, Ana C. C.; Rod, Kenton A.; Hilbert, Jorge; Galdos, Marcelo V.; Cisz, Michelle E.

    2015-12-01

    Rapid expansion in biomass production for biofuels and bioenergy in the Americas is increasing demand on the ecosystem resources required to sustain soil and site productivity. We review the current state of knowledge and highlight gaps in research on biogeochemical processes and ecosystem sustainability related to biomass production. Biomass production systems incrementally remove greater quantities of organic matter, which in turn affects soil organic matter and associated carbon and nutrient storage (and hence long-term soil productivity) and off-site impacts. While these consequences have been extensively studied for some crops and sites, the ongoing and impending impacts of biomass removal require management strategies for ensuring that soil properties and functions are sustained for all combinations of crops, soils, sites, climates, and management systems, and that impacts of biomass management (including off-site impacts) are environmentally acceptable. In a changing global environment, knowledge of cumulative impacts will also become increasingly important. Long-term experiments are essential for key crops, soils, and management systems because short-term results do not necessarily reflect long-term impacts, although improved modeling capability may help to predict these impacts. Identification and validation of soil sustainability indicators for both site prescriptions and spatial applications would better inform commercial and policy decisions. In an increasingly inter-related but constrained global context, researchers should engage across inter-disciplinary, inter-agency, and international lines to better ensure the long-term soil productivity across a range of scales, from site to landscape.

  9. Effects of future urban and biofuel crop expansions on the riverine export of phosphorus to the Laurentian Great Lakes

    USGS Publications Warehouse

    LaBeau, Meredith B.; Robertson, Dale M.; Mayer, Alex S.; Pijanowski, Bryan C.; Saad, David A.

    2013-01-01

    Increased phosphorus (P) loadings threaten the health of the world’s largest freshwater resource, the Laurentian Great Lakes (GL). To understand the linkages between land use and P delivery, we coupled two spatially explicit models, the landscape-scale SPARROW P fate and transport watershed model and the Land Transformation Model (LTM) land use change model, to predict future P export from nonpoint and point sources caused by changes in land use. According to LTM predictions over the period 2010–2040, the GL region of the U.S. may experience a doubling of urbanized areas and agricultural areas may increase by 10%, due to biofuel feedstock cultivation. These land use changes are predicted to increase P loadings from the U.S. side of the GL basin by 3.5–9.5%, depending on the Lake watershed and development scenario. The exception is Lake Ontario, where loading is predicted to decrease by 1.8% for one scenario, due to population losses in the drainage area. Overall, urban expansion is estimated to increase P loadings by 3.4%. Agricultural expansion associated with predicted biofuel feedstock cultivation is predicted to increase P loadings by an additional 2.4%. Watersheds that export P most efficiently and thus are the most vulnerable to increases in P sources tend to be found along southern Lake Ontario, southeastern Lake Erie, western Lake Michigan, and southwestern Lake Superior where watershed areas are concentrated along the coastline with shorter flow paths. In contrast, watersheds with high soil permeabilities, fractions of land underlain by tile drains, and long distances to the GL are less vulnerable.

  10. Enzymatic hydrolysis of pretreated waste paper--source of raw material for production of liquid biofuels.

    PubMed

    Brummer, Vladimir; Jurena, Tomas; Hlavacek, Viliam; Omelkova, Jirina; Bebar, Ladislav; Gabriel, Petr; Stehlik, Petr

    2014-01-01

    Enzymatic hydrolysis of waste paper is becoming a perspective way to obtain raw material for production of liquid biofuels. Reducing sugars solutions that arise from the process of saccharification are a precursors for following or simultaneous fermentation to ethanol. Different types of waste paper were evaluated, in terms of composition and usability, in order to select the appropriate type of the waste paper for the enzymatic hydrolysis process. Novozymes® enzymes NS50013 and NS50010 were used in a laboratory scale trials. Technological conditions, which seem to be the most suitable for hydrolysis after testing on cellulose pulp and filter paper, were applied to hydrolysis of widely available waste papers - offset paper, cardboard, recycled paper in two qualities, matte MYsol offset paper and for comparison again on model materials. The highest yields were achieved for the cardboard, which was further tested using various pretreatment combinations in purpose of increasing the hydrolysis yields. PMID:24314601

  11. Trash to treasure: production of biofuels and commodity chemicals via syngas fermenting microorganisms.

    PubMed

    Latif, Haythem; Zeidan, Ahmad A; Nielsen, Alex T; Zengler, Karsten

    2014-06-01

    Fermentation of syngas is a means through which unutilized organic waste streams can be converted biologically into biofuels and commodity chemicals. Despite recent advances, several issues remain which limit implementation of industrial-scale syngas fermentation processes. At the cellular level, the energy conservation mechanism of syngas fermenting microorganisms has not yet been entirely elucidated. Furthermore, there was a lack of genetic tools to study and ultimately enhance their metabolic capabilities. Recently, substantial progress has been made in understanding the intricate energy conservation mechanisms of these microorganisms. Given the complex relationship between energy conservation and metabolism, strain design greatly benefits from systems-level approaches. Numerous genetic manipulation tools have also been developed, paving the way for the use of metabolic engineering and systems biology approaches. Rational strain designs can now be deployed resulting in desirable phenotypic traits for large-scale production. PMID:24863900

  12. The Role of Symbiotic Nitrogen Fixation in Sustainable Production of Biofuels

    PubMed Central

    Biswas, Bandana; Gresshoff, Peter M.

    2014-01-01

    With the ever-increasing population of the world (expected to reach 9.6 billion by 2050), and altered life style, comes an increased demand for food, fuel and fiber. However, scarcity of land, water and energy accompanied by climate change means that to produce enough to meet the demands is getting increasingly challenging. Today we must use every avenue from science and technology available to address these challenges. The natural process of symbiotic nitrogen fixation, whereby plants such as legumes fix atmospheric nitrogen gas to ammonia, usable by plants can have a substantial impact as it is found in nature, has low environmental and economic costs and is broadly established. Here we look at the importance of symbiotic nitrogen fixation in the production of biofuel feedstocks; how this process can address major challenges, how improving nitrogen fixation is essential, and what we can do about it. PMID:24786096

  13. Biofuels Research at EPA

    EPA Science Inventory

    The development of sustainable and clean biofuels is a national priority. To do so requires a life-cycle approach that includes consideration of feedstock production and logistics, and biofuel production, distribution, and end use. The US Environmental Protection Agency is suppor...

  14. Development of Agave as a dedicated biomass source: production of biofuels from whole plants

    DOE PAGESBeta

    Mielenz, Jonathan R.; Rodriguez, Jr, Miguel; Thompson, Olivia A; Yang, Xiaohan; Yin, Hengfu

    2015-01-01

    Background: Agave species can grow well in semi-arid marginal agricultural lands around the world. Selected Agave species are used largely for alcoholic beverage production in Mexico. There are expanding research efforts to use the plentiful residues (bagasse) for ethanol production as the beverage manufacturing process only uses the juice from the central core of mature plants. Here we investigate the potential of over a dozen Agave species, including three from cold semi-arid regions of the United States, to produce biofuels using the whole plant. Results: Ethanol was readily produced by Saccharomyces cerevisiae from hydrolysate of ten whole Agaves with themore » use of a proper blend of biomass degrading enzymes that overcomes toxicity of most of the species tested. Unlike yeast fermentations, Clostridium beijerinckii produced butanol plus acetone from nine species tested. Butyric acid, a precursor of butanol, was also present due to incomplete conversion during the screening process. Since Agave contains high levels of free and poly-fructose which are readily destroyed by acidic pretreatment, a two step process was used developed to depolymerized poly-fructose while maintaining its fermentability. The hydrolysate from before and after dilute acid processing was used in C. beijerinckii acetone and butanol fermentations with selected Agave species. Conclusions: Results have shown Agave s potential to be a source of fermentable sugars beyond the existing beverage species to now include species previously unfermentable by yeast, including cold tolerant lines. This development may stimulate development of Agave as a dedicated feedstock for biofuels in semi-arid regions throughout the globe.« less

  15. Thermophysical characterization of the seeds of invasive Chinese tallow tree: importance for biofuel production.

    PubMed

    Picou, Laura; Boldor, Doran

    2012-10-16

    The limited supply of traditional fossil based fuels, and increased concern about their environmental impact has driven the interest in the utilization of biomass based energy sources, including those that are underutilized or otherwise nuisance species such as Chinese tallow trees (Triadica sebifera [L.]). This species is a prolific seeds producer, and this paper shows that they contain more than 50% lipids by mass that are suitable for conversion into biodiesel. We present here, for the first time, the seeds' thermophysical properties important for biofuel production. The seeds were characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and ultimate analysis; their thermal conductivity, thermal diffusivity, and specific heat were determined. The characterization results were correlated to fatty acid composition and lipid content for whole seeds and individual layers, as well as to the protein, hemicellulose, cellulose, and lignin content. The TGA analysis indicated the presence, in addition to lipids, of hemicellulose, cellulose, lignin, and proteins, depending on the layer analyzed. Thermal conductivity and specific heat were, respectively 0.14 ± 0.007 W/mK and 3843.5 ± 171.16 J/kgK for wax, 0.20 ± 0.002 W/mK and 2018.7 ± 5.18 J/kgK for shells, 0.13 ± 0.0 W/mK and 1237 ± 3.15 J/kgK for internal kernel, and 0.13 ± 0.000 W/mK and 2833.9 ± 104.11 J/kgK for whole seeds. These properties and characterization method can be further used in engineering analysis used to determine the most optimum processing method for production of biofuels from this feedstock. PMID:23013244

  16. Development of Agave as a dedicated biomass source: production of biofuels from whole plants

    SciTech Connect

    Mielenz, Jonathan R.; Rodriguez, Jr, Miguel; Thompson, Olivia A; Yang, Xiaohan; Yin, Hengfu

    2015-01-01

    Background: Agave species can grow well in semi-arid marginal agricultural lands around the world. Selected Agave species are used largely for alcoholic beverage production in Mexico. There are expanding research efforts to use the plentiful residues (bagasse) for ethanol production as the beverage manufacturing process only uses the juice from the central core of mature plants. Here we investigate the potential of over a dozen Agave species, including three from cold semi-arid regions of the United States, to produce biofuels using the whole plant. Results: Ethanol was readily produced by Saccharomyces cerevisiae from hydrolysate of ten whole Agaves with the use of a proper blend of biomass degrading enzymes that overcomes toxicity of most of the species tested. Unlike yeast fermentations, Clostridium beijerinckii produced butanol plus acetone from nine species tested. Butyric acid, a precursor of butanol, was also present due to incomplete conversion during the screening process. Since Agave contains high levels of free and poly-fructose which are readily destroyed by acidic pretreatment, a two step process was used developed to depolymerized poly-fructose while maintaining its fermentability. The hydrolysate from before and after dilute acid processing was used in C. beijerinckii acetone and butanol fermentations with selected Agave species. Conclusions: Results have shown Agave s potential to be a source of fermentable sugars beyond the existing beverage species to now include species previously unfermentable by yeast, including cold tolerant lines. This development may stimulate development of Agave as a dedicated feedstock for biofuels in semi-arid regions throughout the globe.

  17. Relative importance of climate and land surface changes on hydrologic changes in the US Midwest since the 1930s: Implications for biofuel production

    NASA Astrophysics Data System (ADS)

    Xu, Xianli; Scanlon, Bridget R.; Schilling, Keith; Sun, Alex

    2013-08-01

    The US Midwest is an important area of first generation biofuels, accounting for 80-90% of US corn and soybean production (2009-2011). However, there are potential adverse impacts of biofuel production on water resources in this area. The objective of this study was to assess potential impacts of biofuel production on water resources by exploring relationships between hydrologic changes and climate and land surface changes based on long-term (˜1930s-2010) stream gage and climate data from 55 unregulated watersheds in the US Midwest. Long-term trends in climate (precipitation and potential evapotranspiration) and flow were evaluated. Sensitivity of changes in annual streamflow and baseflow to climate was evaluated using climate elasticity (sensitivity) and the residuals were attributed to land surface changes. Results show that streamflow increased significantly (p < 0.05) in 35% (19/55) of watersheds (median 2.4 ± 0.3 mm/year), baseflow increased in 58% of watersheds (median 1.1 ± 0.4 mm/year), and baseflow index (baseflow/streamflow, BFI) increased in 42% of watersheds (median 0.2 ± 0.1%/year). Overall, climatic variability contributed more than land surface change to streamflow change (61 ± 19% vs. 40 ± 18%), while land surface change contributed much more to baseflow (74 ± 10% vs. 27 ± 10%; 2.7 times higher) and to BFI (119 ± 14% vs. 27 ± 18%; 4.4 times higher) than climate change. Watersheds (25/55, 45%) with no significant trend in climate but with significant flow trends provide direct evidence that the Midwest land surface change (cropping system and related land management) significantly impacted flow processes. Restricting analysis to these watersheds shows that land surface change contributed 2.0 times more than climate variability/change to streamflow change, 3.2 times more to baseflow change, and 7.7 times more to BFI change. The importance of past land surface changes on hydrology suggests that any future land surface changes, such as biofuel expansion or changing biofuel feedstocks, should consider impacts on the hydrology.

  18. Spatial forecasting of switchgrass productivity under current and future climate change scenarios.

    PubMed

    Behrman, Kathrine D; Kiniry, James R; Winchell, Michael; Juenger, Thomas E; Keitt, Timothy H

    2013-01-01

    Evaluating the potential of alternative energy crops across large geographic regions, as well as over time, is a necessary component to determining if biofuel production is feasible and sustainable in the face of growing production demands and climatic change. Switchgrass (Panicum virgatum L.), a native perennial herbaceous grass, is a promising candidate for cellulosic feedstock production. In this study, current and future (from 2080 to 2090) productivity is estimated across the central and eastern United States using ALMANAC, a mechanistic model that simulates plant growth over time. The ALMANAC model was parameterized for representative ecotypes of switchgrass. Our results indicate substantial variation in switchgrass productivity both within regions and over time. States along the Gulf Coast, southern Atlantic Coast, and in the East North Central Midwest have the highest current biomass potential. However, these areas also contain critical wetland habitat necessary for the maintenance of biodiversity and agricultural lands necessary for food production. The southern United States is predicted to have the largest decrease in future biomass production. The Great Plains are expected to experience large increases in productivity by 2080-2090 due to climate change. In general, regions where future temperature and precipitation are predicted to increase are also where larger future biomass production is expected. In contrast, regions that show a future decrease in precipitation are associated with smaller future biomass production. Switchgrass appears to be a promising biofuel crop for the central and eastern United States, with local biomass predicted to be high (>10 Mg/ha) for approximately 50% of the area studied for each climate scenario. In order to minimize land conversion and loss of biodiversity, areas that currently have and maintain high productivity under climate change should be targeted for their long-term growth potential. PMID:23495637

  19. Biological potential of microalgae in China for biorefinery-based production of biofuels and high value compounds.

    PubMed

    Li, Jingjing; Liu, Ying; Cheng, Jay J; Mos, Michal; Daroch, Maurycy

    2015-12-25

    Microalgae abundance and diversity in China shows promise for identifying suitable strains for developing algal biorefinery. Numerous strains of microalgae have already been assessed as feedstocks for bioethanol and biodiesel production, but commercial scale algal biofuel production is yet to be demonstrated, most likely due to huge energy costs associated with algae cultivation, harvesting and processing. Biorefining, integrated processes for the conversion of biomass into a variety of products, can improve the prospects of microalgal biofuels by combining them with the production of high value co-products. Numerous microalgal strains in China have been identified as producers of various high value by-products with wide application in the medicine, food, and cosmetics industries. This paper reviews microalgae resources in China and their potential in producing liquid biofuels (bioethanol and biodiesel) and high value products in an integrated biorefinery approach. Implementation of a 'high value product first' principle should make the integrated process of fuels and chemicals production economically feasible and will ensure that public and private interest in the development of microalgal biotechnology is maintained. PMID:25686716

  20. Production of biofuels and biochemicals by in vitro synthetic biosystems: Opportunities and challenges.

    PubMed

    Zhang, Yi-Heng Percival

    2015-11-15

    The largest obstacle to the cost-competitive production of low-value and high-impact biofuels and biochemicals (called biocommodities) is high production costs catalyzed by microbes due to their inherent weaknesses, such as low product yield, slow reaction rate, high separation cost, intolerance to toxic products, and so on. This predominant whole-cell platform suffers from a mismatch between the primary goal of living microbes - cell proliferation and the desired biomanufacturing goal - desired products (not cell mass most times). In vitro synthetic biosystems consist of numerous enzymes as building bricks, enzyme complexes as building modules, and/or (biomimetic) coenzymes, which are assembled into synthetic enzymatic pathways for implementing complicated bioreactions. They emerge as an alternative solution for accomplishing a desired biotransformation without concerns of cell proliferation, complicated cellular regulation, and side-product formation. In addition to the most important advantage - high product yield, in vitro synthetic biosystems feature several other biomanufacturing advantages, such as fast reaction rate, easy product separation, open process control, broad reaction condition, tolerance to toxic substrates or products, and so on. In this perspective review, the general design rules of in vitro synthetic pathways are presented with eight supporting examples: hydrogen, n-butanol, isobutanol, electricity, starch, lactate,1,3-propanediol, and poly-3-hydroxylbutyrate. Also, a detailed economic analysis for enzymatic hydrogen production from carbohydrates is presented to illustrate some advantages of this system and the remaining challenges. Great market potentials will motivate worldwide efforts from multiple disciplines (i.e., chemistry, biology and engineering) to address the remaining obstacles pertaining to cost and stability of enzymes and coenzymes, standardized building parts and modules, biomimetic coenzymes, biosystem optimization, and scale-up, soon. PMID:25447781

  1. A GIS cost model to assess the availability of freshwater, seawater, and saline groundwater for algal biofuel production in the United States.

    PubMed

    Venteris, Erik R; Skaggs, Richard L; Coleman, Andre M; Wigmosta, Mark S

    2013-05-01

    A key advantage of using microalgae for biofuel production is the ability of some algal strains to thrive in waters unsuitable for conventional crop irrigation such as saline groundwater or seawater. Nonetheless, the availability of sustainable water supplies will provide significant challenges for scale-up and development of algal biofuels. We conduct a partial techno-economic assessment based on the availability of freshwater, saline groundwater, and seawater for use in open pond algae cultivation systems. We explore water issues through GIS-based models of algae biofuel production, freshwater supply (constrained to less than 5% of mean annual flow per watershed) and costs, and cost-distance models for supplying seawater and saline groundwater. We estimate that, combined, these resources can support 9.46 × 10(7) m(3) yr(-1) (25 billion gallons yr(-1)) of renewable biodiesel production in the coterminous United States. Achievement of larger targets requires the utilization of less water efficient sites and relatively expensive saline waters. Despite the addition of freshwater supply constraints and saline water resources, the geographic conclusions are similar to our previous results. Freshwater availability and saline water delivery costs are most favorable for the coast of the Gulf of Mexico and Florida peninsula, where evaporation relative to precipitation is moderate. As a whole, the barren and scrub lands of the southwestern U.S. have limited freshwater supplies, and large net evaporation rates greatly increase the cost of saline alternatives due to the added makeup water required to maintain pond salinity. However, this and similar analyses are particularly sensitive to knowledge gaps in algae growth/lipid production performance and the proportion of freshwater resources available, key topics for future investigation. PMID:23495893

  2. Registration of Three High Fiber Sugar Cane Varieties, L 79-1002, HoCP 91-552 AND Ho 00-961, for Biofuels Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High fiber sugarcane (Saccharum spp. hybrids) varieties, or energy canes, have been shown to be a viable feedstock for biofuel applications. Three high fiber sugarcane varieties, L 79-1002, HoCP 91-552 and Ho 00-961, were released in April 2007 for commercial biofuel production. L 79-1002 averaged 2...

  3. Switchgrass potential on reclaimed surface mines for biofuel production in West Virginia

    NASA Astrophysics Data System (ADS)

    Marra, Michael A.

    The high cost and environmental risks associated with non-renewable energy sources has caused an increased interest in, and development of renewable biofuels. Switchgrass (Panicum virgatum L.), a warm season perennial grass, has been investigated as a source of biofuel feedstock due to its high biomass production on marginal soils, its tolerance of harsh growing conditions, and its ability to provide habitat for wildlife and soil conservation cover. West Virginia contains vast expanses of reclaimed surface mine lands and could potentially benefit from the production of switchgrass as a biofuel feedstock. Furthermore, switchgrass production could satisfy Surface Mining Reclamation and Control Act of 1977 (SMCRA) requirements for reclamation bond release to mine operators. Three separate studies will be discussed in this thesis to determine if switchgrass grown on reclaimed surface mines can produce yields similar to yields from stands grown under normal agronomic conditions and what common surface mining reclamation practices may be most appropriate for growing switchgrass. The first study examined yield production of three commercially-available, upland switchgrass varieties grown on two reclaimed surface mines in production years two, three and four. The Hampshire Hill mine site, which was reclaimed in the late 1990s using top soil and treated municipal sludge, averaged 5,800 kg (ha-yr)-1 of switchgrass compared to 803 kg (ha-yr)-1 at the Hobet 21 site which was reclaimed with crushed, unweathered rock over compacted overburden. Site and variety interacted with Cave-in-Rock as the top performer at the more fertile Hampshire Hill site and Shawnee produced the highest yields at Hobet 21 (7,853 kg ha-1 and 1,086 kg ha-1 averaged across years, respectively). Switchgrass yields increased from 2009 to 2010, but declined from 2010 to 2011. Switchgrass yields from farmlands in this region averaged about 15000 kg (ha-yr)-1 in the research literature, so switchgrass grown on reclaimed lands appears to be about 50% lower. A second study to determine optimal nitrogen and mulch rates for switchgrass establishment began in June 2011 on two newly-reclaimed surface mines. Both sites were seeded at a rate of 11.2 kg pure live seed (PLS) ha-1 of Cave-in-Rock on replicated treatments of 0, 33.6 and 67.0 kg N ha-1, and high and low mulch rates of mulch applied as hydromulch. Switchgrass cover, frequency and yield improved with the addition of any amount of N fertilizer compared to no N application. There was no significant difference in yield associated with high and low levels of N. We also observed that yields were not affected by application of additional mulch. The final study compared a one- and two-harvest system in the fourth year of production at the Hampshire Hill and Hobet 21 sites. There was no increase in yield production utilizing a two-harvest system (2922 kg (ha-yr)-1, averaged across site) compared to a one-harvest system (3029 kg (ha-yr)-1). The data also showed that re-growth collected from July to October in the two-harvest system added negligible yield and that yield collected in July was comparable in one- and two-harvest systems.

  4. Metabolic engineering of Saccharomyces cerevisiae for production of fatty acid-derived biofuels and chemicals.

    PubMed

    Runguphan, Weerawat; Keasling, Jay D

    2014-01-01

    As the serious effects of global climate change become apparent and access to fossil fuels becomes more limited, metabolic engineers and synthetic biologists are looking towards greener sources for transportation fuels. In recent years, microbial production of high-energy fuels by economically efficient bioprocesses has emerged as an attractive alternative to the traditional production of transportation fuels. Here, we engineered the budding yeast Saccharomyces cerevisiae to produce fatty acid-derived biofuels and chemicals from simple sugars. Specifically, we overexpressed all three fatty acid biosynthesis genes, namely acetyl-CoA carboxylase (ACC1), fatty acid synthase 1 (FAS1) and fatty acid synthase 2 (FAS2), in S. cerevisiae. When coupled to triacylglycerol (TAG) production, the engineered strain accumulated lipid to more than 17% of its dry cell weight, a four-fold improvement over the control strain. Understanding that TAG cannot be used directly as fuels, we also engineered S. cerevisiae to produce drop-in fuels and chemicals. Altering the terminal "converting enzyme" in the engineered strain led to the production of free fatty acids at a titer of approximately 400 mg/L, fatty alcohols at approximately 100mg/L and fatty acid ethyl esters (biodiesel) at approximately 5 mg/L directly from simple sugars. We envision that our approach will provide a scalable, controllable and economic route to this important class of chemicals. PMID:23899824

  5. Addressing the challenges for sustainable production of algal biofuels: I. Algal strains and nutrient supply.

    PubMed

    Abdelaziz, Ahmed E M; Leite, Gustavo B; Hallenbeck, Patrick C

    2013-01-01

    Microalgae hold promise for the production of sustainable replacement of fossil fuels due to their high growth rates, ability to grow on non-arable land and their high content, under the proper conditions, of high energy compounds that can be relatively easily chemically converted to fuels using existing technology. However, projected large-scale algal production raises a number of sustainability concerns concerning land use, net energy return, water use and nutrient supply. The state-of-the-art of algal production of biofuels is presented with emphasis on some possible avenues to provide answers to the sustainability questions that have been raised. Here, issues concerning algal strains and supply of nutrients for large-scale production are discussed. Since sustainability concerns necessitate the use of wastewaters for supply of bulk nutrients, emphasis is placed on the composition and suitability of different wastewater streams. At the same time, algal cultivation has proven useful in waste treatment processes, and thus this aspect is also treated in some detail. PMID:24350435

  6. %22Trojan Horse%22 strategy for deconstruction of biomass for biofuels production.

    SciTech Connect

    Simmons, Blake Alexander; Sinclair, Michael B.; Yu, Eizadora; Timlin, Jerilyn Ann; Hadi, Masood Z.; Tran-Gyamfi, Mary

    2011-02-01

    Production of renewable biofuels to displace fossil fuels currently consumed in the transportation sector is a pressing multiagency national priority (DOE/USDA/EERE). Currently, nearly all fuel ethanol is produced from corn-derived starch. Dedicated 'energy crops' and agricultural waste are preferred long-term solutions for renewable, cheap, and globally available biofuels as they avoid some of the market pressures and secondary greenhouse gas emission challenges currently facing corn ethanol. These sources of lignocellulosic biomass are converted to fermentable sugars using a variety of chemical and thermochemical pretreatments, which disrupt cellulose and lignin cross-links, allowing exogenously added recombinant microbial enzymes to more efficiently hydrolyze the cellulose for 'deconstruction' into glucose. This process is plagued with inefficiencies, primarily due to the recalcitrance of cellulosic biomass, mass transfer issues during deconstruction, and low activity of recombinant deconstruction enzymes. Costs are also high due to the requirement for enzymes and reagents, and energy-intensive cumbersome pretreatment steps. One potential solution to these problems is found in synthetic biology-engineered plants that self-produce a suite of cellulase enzymes. Deconstruction can then be integrated into a one-step process, thereby increasing efficiency (cellulose-cellulase mass-transfer rates) and reducing costs. The unique aspects of our approach are the rationally engineered enzymes which become Trojan horses during pretreatment conditions. During this study we rationally engineered Cazy enzymes and then integrated them into plant cells by multiple transformation techniques. The regenerated plants were assayed for first expression of these messages and then for the resulting proteins. The plants were then subjected to consolidated bioprocessing and characterized in detail. Our results and possible implications of this work on developing dedicated energy crops and their advantage in a consolidated bioprocessing system.

  7. Natural Gas and Cellulosic Biomass: A Clean Fuel Combination? Determining the Natural Gas Blending Wall in Biofuel Production.

    PubMed

    M Wright, Mark; Seifkar, Navid; Green, William H; Román-Leshkov, Yuriy

    2015-07-01

    Natural gas has the potential to increase the biofuel production output by combining gas- and biomass-to-liquids (GBTL) processes followed by naphtha and diesel fuel synthesis via Fischer-Tropsch (FT). This study reflects on the use of commercial-ready configurations of GBTL technologies and the environmental impact of enhancing biofuels with natural gas. The autothermal and steam-methane reforming processes for natural gas conversion and the gasification of biomass for FT fuel synthesis are modeled to estimate system well-to-wheel emissions and compare them to limits established by U.S. renewable fuel mandates. We show that natural gas can enhance FT biofuel production by reducing the need for water-gas shift (WGS) of biomass-derived syngas to achieve appropriate H2/CO ratios. Specifically, fuel yields are increased from less than 60 gallons per ton to over 100 gallons per ton with increasing natural gas input. However, GBTL facilities would need to limit natural gas use to less than 19.1% on a LHV energy basis (7.83 wt %) to avoid exceeding the emissions limits established by the Renewable Fuels Standard (RFS2) for clean, advanced biofuels. This effectively constitutes a blending limit that constrains the use of natural gas for enhancing the biomass-to-liquids (BTL) process. PMID:26010031

  8. Hydrothermal treatment of oleaginous yeast for the recovery of free fatty acids for use in advanced biofuel production.

    PubMed

    Espinosa-Gonzalez, Isabel; Parashar, Archana; Bressler, David C

    2014-10-10

    Microbial oils hold great potential as a suitable feedstock for the renewable production of biofuels. Specifically, the use of oleaginous yeasts offers several advantages related to cultivation and quality of lipid products. However, one of the major bottlenecks for large-scale production of yeast oils is found in the lipid extraction process. This work investigated the hydrothermal treatment of oleaginous yeast for hydrolysis and lipid extraction resulting in fatty acids used for biofuel production. The oleaginous yeast, Cryptococcus curvatus, was grown in 5 L bioreactors and the biomass slurry with 53±4% lipid content (dry weight basis) was treated at 280 °C for 1h with an initial pressure of 500 psi in batch stainless steel reactors. The hydrolysis product was separated and each of the resulting streams was further characterized. The hexane soluble fraction contained fatty acids from the hydrolysis of yeast triacylglycerides, and was low in nitrogen and minerals and could be directly integrated as feedstock into pyrolysis processing to produce biofuels. The proposed hydrothermal treatment addresses some current technological bottlenecks associated with traditional methodologies such as dewatering, oil extraction and co-product utilization. It also enhances the feasibility of using microbial biomass for production of renewable fuels and chemicals. PMID:25034431

  9. Selection of native Tunisian microalgae for simultaneous wastewater treatment and biofuel production.

    PubMed

    Jebali, A; Acién, F G; Gómez, C; Fernández-Sevilla, J M; Mhiri, N; Karray, F; Dhouib, A; Molina-Grima, E; Sayadi, S

    2015-12-01

    This paper focuses on the selection of native microalgae strains suitable for wastewater treatment and biofuel production. Four Chlorophyceae strains were isolated from North-eastern Tunisia. Their performances were compared in continuous mode at a 0.3 1/day dilution rate. The biomass productivity and nutrient removal capacity of each microalgae strain were studied. The most efficient strain was identified as Scenedesmus sp. and experiments at different dilution rates from 0.2 to 0.8 1/day were carried out. Maximal biomass productivity of 0.9 g/L day was obtained at 0.6 1/day. The removal of chemical oxygen demand (COD), ammonium and phosphorus was in the range of 92-94%, 61-99% and 93-99%, respectively. Carbohydrates were the major biomass fraction followed by lipids and then proteins. The saponifiable fatty acid content was in the 4.9-13.2% dry biomass range, with more than 50% of total fatty acids being composed of saturated and monosaturated fatty acids. PMID:26409854

  10. The unintended energy impacts of increased nitrate contamination from biofuels production.

    PubMed

    Twomey, Kelly M; Stillwell, Ashlynn S; Webber, Michael E

    2010-01-01

    Increases in corn cultivation for biofuels production, due to the Energy Independence and Security Act of 2007, are likely to lead to increases in nitrate concentrations in both surface and groundwater resources in the United States. These increases might trigger the requirement for additional energy consumption for water treatment to remove the nitrates. While these increasing concentrations of nitrate might pose a human health concern, most water resources were found to be within current maximum contaminant level (MCL) limits of 10 mg L(-1) NO(3)-N. When water resources exceed this MCL, energy-intensive drinking water treatment is required to reduce nitrate levels below 10 mg L(-1). Based on prior estimates of water supplies currently exceeding the nitrate MCL, we calculate that advanced drinking water treatment might require an additional 2360 million kWh annually (for nitrate affected areas only)--a 2100% increase in energy requirements for water treatment in those same areas--to mitigate nitrate contamination and meet the MCL requirement. We predict that projected increases in nitrate contamination in water may impact the energy consumed in the water treatment sector, because of the convergence of several related trends: (1) increasing cornstarch-based ethanol production, (2) increasing nutrient loading in surface water and groundwater resources as a consequence of increased corn-based ethanol production, (3) additional drinking water sources that exceed the MCL for nitrate, and (4) potentially more stringent drinking water standards for nitrate. PMID:20082016

  11. Closing the gap: global potential for increasing biofuel production through agricultural intensification

    NASA Astrophysics Data System (ADS)

    Johnston, Matt; Licker, R.; Foley, J.; Holloway, T.; Mueller, N. D.; Barford, C.; Kucharik, C.

    2011-07-01

    Since the end of World War II, global agriculture has undergone a period of rapid intensification achieved through a combination of increased applications of chemical fertilizers, pesticides, and herbicides, the implementation of best management practice techniques, mechanization, irrigation, and more recently, through the use of optimized seed varieties and genetic engineering. However, not all crops and not all regions of the world have realized the same improvements in agricultural intensity. In this study we examine both the magnitude and spatial variation of new agricultural production potential from closing of 'yield gaps' for 20 ethanol and biodiesel feedstock crops. With biofuels coming under increasing pressure to slow or eliminate indirect land-use conversion, the use of targeted intensification via established agricultural practices might offer an alternative for continued growth. We find that by closing the 50th percentile production gap—essentially improving global yields to median levels—the 20 crops in this study could provide approximately 112.5 billion liters of new ethanol and 8.5 billion liters of new biodiesel production. This study is intended to be an important new resource for scientists and policymakers alike—helping to more accurately understand spatial variation of yield and agricultural intensification potential, as well as employing these data to better utilize existing infrastructure and optimize the distribution of development and aid capital.

  12. European biofuel plan snagged

    SciTech Connect

    Chynoweth, E.

    1992-12-16

    European Commission proposals for a directive aimed at boosting production of biofuels have been set back by the European Parliament and will not be implemented on the January 1, 1993 deadline. Furthermore, the commission has agreed to carry out an environmental impact study on biofuels. European industrial ethanol, fatty acid, and glycerin producers oppose the directive proposals fearing distortions in their markets.

  13. Algal Biofuels Fact Sheet

    SciTech Connect

    2009-10-27

    This fact sheet provides information on algal biofuels, which are generating considerable interest around the world. They may represent a sustainable pathway for helping to meet the U.S. biofuel production targets set by the Energy Independence and Security Act of 2007.

  14. In Field Monitoring of Potential Detrimental Effects of Biofuels Production on Soil Quality

    NASA Astrophysics Data System (ADS)

    Wielopolski, L.; Torbert, A.

    2008-12-01

    Soil organic carbon (SOC) content is recognized as a soil quality indicator that is susceptible to degradation with tillage and with biomass removal from the soil surface. In addition to the reported benefits of leaving crop residue on the soil surface of reducing soil erosion, providing plant nutrients and reducing water losses in runoff events, biomass harvesting for energy production can negatively impact SOC. Reported values of SOC accumulation under conservation tillage systems varied widely from below zero to upwards of 1300 kg/ha/yr depending on the crop type and mean annual temperature. However, very few studies have been conducted with of no-tillage practices with concurrent management of crop residue removal. A negative impact on SOC balance has been reported with extensive biomass removal from cropping systems, but this also is dependent on mean temperature and rainfall amounts. Perennial grasses are strong candidates as a source for biofuel production. These, in turn, will entail very large monoculture fields' with no soil disturbance and extensive harvesting of residues. These conditions may degrade the soil condition by depleting soil's nutrients beyond the point of standard fertilization and reduce the SOC. Thus raising the question of sustainability and, more importantly, challenging the fundamental assertion that the entire cycle of energy production from biofuels, on balance, will reduce the levels of atmospheric carbon dioxide. To monitor soil conditions over vast areas with variable landscapes using current state-of-the-art procedures for soil sampling and analysis by dry combustion presents a formidable task that is labor intensive and time consuming. We propose to implement a new instrument for soil carbon, nitrogen and potassium monitoring in soil that is non-destructive and can be used in either stationary or continuous scanning modes of operation. The instrument senses the elements to an approximate depth of 30 cm and provides true mean values for an arbitrarily large scanned area, in a stationary mode the analyzed soil mass is larger than 200 kg. It is envisioned that the inelastic neutron scattering (INS) system would be more sensitive to changes in the soil conditions, on annual or semi-annual basis, rather than the currently employed methods that require a three or five years period. We report the results obtained with the INS system used in stationary and scanning modes and discuss its merits.

  15. Characterizing compositional changes of Napier grass at different stages of growth for biofuel and biobased products potential.

    PubMed

    Takara, Devin; Khanal, Samir Kumar

    2015-01-01

    Napier grass, Pennisetum purpureum, is a high yielding, perennial feedstock that can be harvested year-round in (sub)tropical geographies of the world. Because of its high moisture content (∼ 80%w/w), Napier grass presents a unique opportunity for fractionation into solid and liquid streams, where the extruded cellulosic fibers can serve as a substrate for biofuel production, and the nutrient-rich juice can serve as a substrate for co-product generation. The aim of this study evaluated the effects of biomass age on constituents relevant to biofuel and biobased product generation. Although obvious morphological changes can be observed in the field due to natural senescence, the results obtained in this work suggested that the cellulose content does not change significantly with respect to age. Data surrounding the hemicellulose and lignin contents, however, were inconclusive as their degree of significance varied with the statistics applied to analyze the raw data. PMID:25727997

  16. A self-sustaining advanced lignocellulosic biofuel production by integration of anaerobic digestion and aerobic fungal fermentation.

    PubMed

    Zhong, Yuan; Ruan, Zhenhua; Zhong, Yingkui; Archer, Steven; Liu, Yan; Liao, Wei

    2015-03-01

    High energy demand hinders the development and application of aerobic microbial biofuel production from lignocellulosic materials. In order to address this issue, this study focused on developing an integrated system including anaerobic digestion and aerobic fungal fermentation to convert corn stover, animal manure and food wastes into microbial lipids for biodiesel production. Dairy manure and food waste were first anaerobically digested to produce energy and solid digestate (AD fiber). AD fiber and corn stover were then processed by a combined alkali and acid hydrolysis, followed by fungal lipid accumulation. The integrated process can generate 1L biodiesel and 1.9 kg methane from 12.8 kg dry dairy manure, 3.1 kg dry food wastes and 12.2 kg dry corn stover with a positive net energy of 57 MJ, which concludes a self-sustaining lignocellulosic biodiesel process and provides a new route to co-utilize corn stover and organic wastes for advanced biofuel production. PMID:25543542

  17. Stimulating learning-by-doing in advanced biofuels: effectiveness of alternative policies

    NASA Astrophysics Data System (ADS)

    Chen, Xiaoguang; Khanna, Madhu; Yeh, Sonia

    2012-12-01

    This letter examines the effectiveness of various biofuel and climate policies in reducing future processing costs of cellulosic biofuels due to learning-by-doing. These policies include a biofuel production mandate alone and supplementing the biofuel mandate with other policies, namely a national low carbon fuel standard, a cellulosic biofuel production tax credit or a carbon price policy. We find that the binding biofuel targets considered here can reduce the unit processing cost of cellulosic ethanol by about 30% to 70% between 2015 and 2035 depending on the assumptions about learning rates and initial costs of biofuel production. The cost in 2035 is more sensitive to the speed with which learning occurs and less sensitive to uncertainty in the initial production cost. With learning rates of 5-10%, cellulosic biofuels will still be at least 40% more expensive than liquid fossil fuels in 2035. The addition of supplementary low carbon/tax credit policies to the mandate that enhance incentives for cellulosic biofuels can achieve similar reductions in these costs several years earlier than the mandate alone; the extent of these incentives differs across policies and different kinds of cellulosic biofuels.

  18. N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels

    NASA Astrophysics Data System (ADS)

    Crutzen, P. J.; Mosier, A. R.; Smith, K. A.; Winiwarter, W.

    2007-08-01

    The relationship, on a global basis, between the amount of N fixed by chemical, biological or atmospheric processes entering the terrestrial biosphere, and the total emission of nitrous oxide (N2O), has been re-examined, using known global atmospheric removal rates and concentration growth of N2O as a proxy for overall emissions. The relationship, in both the pre-industrial period and in recent times, after taking into account the large-scale changes in synthetic N fertiliser production and deforestation, is consistent, showing an overall conversion factor of 3-5%. This factor is covered only in part by the ~1% of "direct" emissions from agricultural crop lands estimated by IPCC (2006), or the "indirect" emissions cited therein. This means that the extra N2O entering the atmosphere as a result of using N to produce crops for biofuels will also be correspondingly greater than that estimated just on the basis of IPCC (2006). When the extra N2O emission from biofuel production is calculated in "CO2-equivalent" global warming terms, and compared with the quasi-cooling effect of "saving" emissions of fossil fuel derived CO2, the outcome is that the production of commonly used biofuels, such as biodiesel from rapeseed and bioethanol from corn (maize), can contribute as much or more to global warming by N2O emissions than cooling by fossil fuel savings. Crops with less N demand, such as grasses and woody coppice species have more favourable climate impacts. This analysis only considers the conversion of biomass to biofuel. It does not take into account the use of fossil fuel on the farms and for fertilizer and pesticide production, but it also neglects the production of useful co-products. Both factors partially compensate each other. This needs to be analyzed in a full life cycle assessment.

  19. Unintended Environmental Consequences of a Global Biofuels Program

    NASA Astrophysics Data System (ADS)

    Kicklighter, D. W.; Gurgel, A. C.; Melillo, J. M.; Reilly, J.; Cronin, T. W.; Felzer, B. S.; Paltsev, S.; Schlosser, C. A.; Sokolov, A. P.

    2008-12-01

    Biofuels are being promoted as an important part of the global energy mix to meet the climate change challenge. The environmental costs of biofuels produced with current technologies at small scales have been studied, but little research has been done on the consequences of an aggressive global biofuels program with advanced technologies using cellulosic feedstocks. Using a simulation modeling approach, we explore two scenarios for cellulosic biofuels production and find that with either one, biofuels could make a substantial contribution to meeting global-scale energy needs in the future, but with significant unintended environmental consequences. If forests are cleared to grow cellulosic biofuels crops, we estimate that about 105 Pg C would be released to the atmosphere as carbon dioxide and would cancel any greenhouse-gas savings from the substitution of biofuels for fossil fuels during the first half of the 21st century. Alternatively, if most cellulosic biofuels are grown on previously cleared land or land cleared of low-stature natural vegetation, we estimate that up to 30 Pg C would still be released to the atmosphere before a net greenhouse gas benefit from a global biofuels program is realized about the middle of the 21st century. With either alternative, we expect most of the world's cellulosic biofuels crops (14 to 15 million km2) to be grown on the relatively inexpensive but productive lands of the sub-tropics and tropics, with negative impacts on the biodiversity of these regions. Cellulosic biofuels may yet serve as a crucial wedge in the solution to the climate change problem, but must be deployed with caution so as not to jeopardize biodiversity, compromise ecosystems services, or undermine climate policy.

  20. A Comparison of the Microbial Production and Combustion Characteristics of Three Alcohol Biofuels: Ethanol, 1-Butanol, and 1-Octanol.

    PubMed

    Kremer, Florian; Blank, Lars M; Jones, Patrik R; Akhtar, M Kalim

    2015-01-01

    Over the last decade, microbes have been engineered for the manufacture of a variety of biofuels. Saturated linear-chain alcohols have great potential as transport biofuels. Their hydrocarbon backbones, as well as oxygenated content, confer combustive properties that make it suitable for use in internal combustion engines. Herein, we compared the microbial production and combustion characteristics of ethanol, 1-butanol, and 1-octanol. In terms of productivity and efficiency, current microbial platforms favor the production of ethanol. From a combustion standpoint, the most suitable fuel for spark-ignition engines would be ethanol, while for compression-ignition engines it would be 1-octanol. However, any general conclusions drawn at this stage regarding the most superior biofuel would be premature, as there are still many areas that need to be addressed, such as large-scale purification and pipeline compatibility. So far, the difficulties in developing and optimizing microbial platforms for fuel production, particularly for newer fuel candidates, stem from our poor understanding of the myriad biological factors underpinning them. A great deal of attention therefore needs to be given to the fundamental mechanisms that govern biological processes. Additionally, research needs to be undertaken across a wide range of disciplines to overcome issues of sustainability and commercial viability. PMID:26301219

  1. A Comparison of the Microbial Production and Combustion Characteristics of Three Alcohol Biofuels: Ethanol, 1-Butanol, and 1-Octanol

    PubMed Central

    Kremer, Florian; Blank, Lars M.; Jones, Patrik R.; Akhtar, M. Kalim

    2015-01-01

    Over the last decade, microbes have been engineered for the manufacture of a variety of biofuels. Saturated linear-chain alcohols have great potential as transport biofuels. Their hydrocarbon backbones, as well as oxygenated content, confer combustive properties that make it suitable for use in internal combustion engines. Herein, we compared the microbial production and combustion characteristics of ethanol, 1-butanol, and 1-octanol. In terms of productivity and efficiency, current microbial platforms favor the production of ethanol. From a combustion standpoint, the most suitable fuel for spark-ignition engines would be ethanol, while for compression-ignition engines it would be 1-octanol. However, any general conclusions drawn at this stage regarding the most superior biofuel would be premature, as there are still many areas that need to be addressed, such as large-scale purification and pipeline compatibility. So far, the difficulties in developing and optimizing microbial platforms for fuel production, particularly for newer fuel candidates, stem from our poor understanding of the myriad biological factors underpinning them. A great deal of attention therefore needs to be given to the fundamental mechanisms that govern biological processes. Additionally, research needs to be undertaken across a wide range of disciplines to overcome issues of sustainability and commercial viability. PMID:26301219

  2. Biofuels and sustainability.

    PubMed

    Solomon, Barry D

    2010-01-01

    Interest in liquid biofuels production and use has increased worldwide as part of government policies to address the growing scarcity and riskiness of petroleum use, and, at least in theory, to help mitigate adverse global climate change. The existing biofuels markets are dominated by U.S. ethanol production based on cornstarch, Brazilian ethanol production based on sugarcane, and European biodiesel production based on rapeseed oil. Other promising efforts have included programs to shift toward the production and use of biofuels based on residues and waste materials from the agricultural and forestry sectors, and perennial grasses, such as switchgrass and miscanthus--so-called cellulosic ethanol. This article reviews these efforts and the recent literature in the context of ecological economics and sustainability science. Several common dimensions for sustainable biofuels are discussed: scale (resource assessment, land availability, and land use practices); efficiency (economic and energy); equity (geographic distribution of resources and the "food versus fuel" debate); socio-economic issues; and environmental effects and emissions. Recent proposals have been made for the development of sustainable biofuels criteria, culminating in standards released in Sweden in 2008 and a draft report from the international Roundtable on Sustainable Biofuels. These criteria hold promise for accelerating a shift away from unsustainable biofuels based on grain, such as corn, and toward possible sustainable feedstock and production practices that may be able to meet a variety of social, economic, and environmental sustainability criteria. PMID:20146765

  3. Research and development for algae-based technologies in Korea: a review of algae biofuel production.

    PubMed

    Hong, Ji Won; Jo, Seung-Woo; Yoon, Ho-Sung

    2015-03-01

    This review covers recent research and development (R&D) activities in the field of algae-based biofuels in Korea. As South Korea's energy policy paradigm has focused on the development of green energies, the government has funded several algae biofuel R&D consortia and pilot projects. Three major programs have been launched since 2009, and significant efforts are now being made to ensure a sustainable supply of algae-based biofuels. If these R&D projects are executed as planned for the next 10 years, they will enable us to overcome many technical barriers in algae biofuel technologies and help Korea to become one of the leading countries in green energy by 2020. PMID:24496987

  4. Neochloris oleabundans UTEX #1185: a suitable renewable lipid source for biofuel production.

    PubMed

    Gouveia, Luísa; Marques, Ana Evangelista; da Silva, Teresa Lopes; Reis, Alberto

    2009-06-01

    Energy crises, global warming, and climatic changes call for technological and commercial advances in manufacturing high-quality transportation fuels from unconventional feedstocks. Microalgae is one of the most promising sources of biofuels due to the high yields attained per unit area and because it does not displace food crops. Neochloris oleabundans (Neo) microalga is an important promising microbial source of single-cell oil (SCO). Different experimental growth and lipid production conditions were evaluated and compared by using optical density (540 nm), dry-weight determination, and flow cytometry (FC). Best Neo average biomass productivity was obtained at 30 degrees C under conditions of nitrogen-sufficiency and CO(2) supplementation (N+/30 degrees C/CO(2)), with an average doubling time of 1.4 days. The second and third highest productivities occurred with N-sufficient cultures without CO(2) supplementation at 26 degrees C (N+/26 degrees C) and at 30 degrees C (N+/30 degrees C), with doubling times of 1.7 and 2.2 days, respectively. Microbial lipid production was monitored by flow cytometry using Nile red (NR), a lipophilic fluorochrome that possesses several advantageous characteristics for in situ screening near real time (at line). Results showed maximum lipid content (56%) after 6 days of nitrogen depletion under nitrogen starvation without CO(2) supplementation (N-/30 degrees C), followed by N-/30 degrees C/CO(2) and N-/26 degrees C conditions with 52% lipid content, after 5 and 6 days of N starvation, respectively. The adequate fatty acid profile and iodine value of Neo lipids reinforced this microalga as a good source of SCO, in particular for use as biodiesel. PMID:19377896

  5. Exploiting diversity and synthetic biology for the production of algal biofuels.

    PubMed

    Georgianna, D Ryan; Mayfield, Stephen P

    2012-08-16

    Modern life is intimately linked to the availability of fossil fuels, which continue to meet the world's growing energy needs even though their use drives climate change, exhausts finite reserves and contributes to global political strife. Biofuels made from renewable resources could be a more sustainable alternative, particularly if sourced from organisms, such as algae, that can be farmed without using valuable arable land. Strain development and process engineering are needed to make algal biofuels practical and economically viable. PMID:22895338

  6. Metabolic Engineering of Clostridium thermocellum for Biofuel Production (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)

    SciTech Connect

    Guess, Adam

    2013-03-01

    Adam Guss of Oak Ridge National Lab on "Metabolic engineering of Clostridium thermocellum for biofuel production" at the 8th Annual Genomics of Energy & Environment Meeting on March 28, 2013 in Walnut Creek, Calif.

  7. Strategies for the production of cell wall-deconstructing enzymes in lignocellulosic biomass and their utilization for biofuel production.

    PubMed

    Park, Sang-Hyuck; Ong, Rebecca Garlock; Sticklen, Mariam

    2016-06-01

    Microbial cell wall-deconstructing enzymes are widely used in the food, wine, pulp and paper, textile, and detergent industries and will be heavily utilized by cellulosic biorefineries in the production of fuels and chemicals. Due to their ability to use freely available solar energy, genetically engineered bioenergy crops provide an attractive alternative to microbial bioreactors for the production of cell wall-deconstructing enzymes. This review article summarizes the efforts made within the last decade on the production of cell wall-deconstructing enzymes in planta for use in the deconstruction of lignocellulosic biomass. A number of strategies have been employed to increase enzyme yields and limit negative impacts on plant growth and development including targeting heterologous enzymes into specific subcellular compartments using signal peptides, using tissue-specific or inducible promoters to limit the expression of enzymes to certain portions of the plant or certain times, and fusion of amplification sequences upstream of the coding region to enhance expression. We also summarize methods that have been used to access and maintain activity of plant-generated enzymes when used in conjunction with thermochemical pretreatments for the production of lignocellulosic biofuels. PMID:26627868

  8. Measuring and moderating the water resource impact of biofuel production and trade

    NASA Astrophysics Data System (ADS)

    Fingerman, Kevin Robert

    Energy systems and water resources are inextricably linked, especially in the case of bioenergy, which can require up to three orders of magnitude more water than other energy carriers. Water scarcity already affects about 1 in 5 people globally, and stands to be exacerbated in many locales by current biofuel expansion plans. This dissertation engages with several of the analytical and governance challenges raised by this connection between bioenergy expansion and global water resources. My examination begins with an overview of important concepts in water resource analysis, followed by a review of current literature on the water impacts of most major energy pathways. I then report on a case study of ethanol fuel in California. This work employed a coupled agro-climatic and life cycle assessment (LCA) model to estimate the water resource impacts of several bioenergy expansion scenarios at a county-level resolution. It shows that ethanol production in California regularly consumes more than 1000 gallons of water per gallon of fuel produced, and that 99% of life-cycle water consumption occurs in the feedstock cultivation phase. This analysis then delves into the complexity of life cycle impact assessment for water resources. Despite improvements in water accounting methods, impact assessment must contend with the fact that different water sources are not necessarily commensurable, and that impacts depend on the state of the resource base that is drawn upon. I adapt water footprinting and LCA techniques to the bioenergy context, describing comprehensive inventory approaches and developing a process for characterizing (weighting) consumption values to enable comparison across resource bases. This process draws on metrics of water stress, accounting for environmental flow requirements, climatic variability, and non-linearity of water stress effects. My assessment framework was developed in hopes that it would be useful in managing the risks and impacts it describes. The primary actors in this governance effort are government regulators, whose policies and incentives continue to drive and to shape the expansion of the bioenergy industry. However, the ability of governments to manage the impacts of biofuels is severely constrained by their obligations under international trade law. This dissertation concludes, therefore, with a detailed investigation into relevant precedents under the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO). I use these precedents to identify the policy tools that governments would be able to bring to bear in moderating the water resource impacts and myriad other environmental and social concerns raised by bioenergy expansion.

  9. The Selective Use of Hypochlorite to Prevent Pond Crashes for Algae-Biofuel Production.

    PubMed

    Park, Sichoon; Van Ginkel, Steven W; Pradeep, Priya; Igou, Thomas; Yi, Christine; Snell, Terry; Chen, Yongsheng

    2016-01-01

    Although algae-biofuels have many advantages including high areal productivity, algae can be preyed upon by amoebas, protozoans, ciliates, and rotifers, particularly in open pond systems. Thus, these higher organisms need to be controlled. In this study, Chlorella kessleri was used as the algal culture and Brachionus calyciflorus as the source of predation. The effect of sodium hypochlorite (bleach) was tested with the goal of totally inhibiting the rotifer while causing minor inhibition to the alga. The 24-hr LC(50) for B. calyciflorus in spring water was 0.198 mg Cl/L while the 24-hr LC(50) for C. kessleri was 0.321 mg Cl/L. However, chlorine dissipates rapidly as the algae serves as reductant. Results showed a chlorine dosage between 0.45 to 0.6 mg Cl/L and a dosing interval of two hours created the necessary chlorine concentrations to inhibit predation while letting the algae grow; thus giving algae farmers a tool to prevent pond crashes. PMID:26803029

  10. Production of biofuel from waste cooking palm oil using nanocrystalline zeolite as catalyst: process optimization studies.

    PubMed

    Taufiqurrahmi, Niken; Mohamed, Abdul Rahman; Bhatia, Subhash

    2011-11-01

    The catalytic cracking of waste cooking palm oil to biofuel was studied over different types of nano-crystalline zeolite catalysts in a fixed bed reactor. The effect of reaction temperature (400-500 °C), catalyst-to-oil ratio (6-14) and catalyst pore size of different nanocrystalline zeolites (0.54-0.80 nm) were studied over the conversion of waste cooking palm oil, yields of Organic Liquid Product (OLP) and gasoline fraction in the OLP following central composite design (CCD). The response surface methodology was used to determine the optimum value of the operating variables for maximum conversion as well as maximum yield of OLP and gasoline fraction, respectively. The optimum reaction temperature of 458 °C with oil/catalyst ratio=6 over the nanocrystalline zeolite Y with pore size of 0.67 nm gave 86.4 wt% oil conversion, 46.5 wt% OLP yield and 33.5 wt% gasoline fraction yield, respectively. The experimental results were in agreement with the simulated values within an experimental error of less than 5%. PMID:21924606

  11. Developing Research Capabilities in Energy Biosciences: Design principles of photosynthetic biofuel production.

    SciTech Connect

    Donald D. Brown; David Savage

    2012-06-30

    The current fossil fuel-based energy infrastructure is not sustainable. Solar radiation is a plausible alternative, but realizing it as such will require significant technological advances in the ability to harvest light energy and convert it into suitable fuels. The biological system of photosynthesis can carry out these reactions, and in principle could be engineered using the tools of synthetic biology. One desirable implementation would be to rewire the reactions of a photosynthetic bacterium to direct the energy harvested from solar radiation into the synthesis of the biofuel H2. Proposed here is a series of experiments to lay the basic science groundwork for such an attempt. The goal is to elucidate the transcriptional network of photosynthesis using a novel driver-reporter screen, evolve more robust hydrogenases for improved catalysis, and to test the ability of the photosynthetic machinery to directly produce H2 in vivo. The results of these experiments will have broad implications for the understanding of photosynthesis, enzyme function, and the engineering of biological systems for sustainable energy production. The ultimate impact could be a fundamental transformation of the world's energy economy.

  12. Algae harvesting for biofuel production: influences of UV irradiation and polyethylenimine (PEI) coating on bacterial biocoagulation.

    PubMed

    Agbakpe, Michael; Ge, Shijian; Zhang, Wen; Zhang, Xuezhi; Kobylarz, Patricia

    2014-08-01

    There is a pressing need to develop efficient and sustainable separation technologies to harvest algae for biofuel production. In this work, two bacterial species (Escherichia coli and Rhodococus sp.) were used as biocoagulants to harvest Chlorella zofingiensis and Scenedesmus dimorphus. The influences of UV irradiation and polyethylenimine (PEI)-coating on the algal harvesting efficiency were investigated. Results showed that the UV irradiation could slightly enhance bacteria-algae biocoagulation and algal harvesting efficiency. In contrast, the PEI-coated E. coli cells noticeably increased the harvesting efficiencies from 23% to 83% for S. dimorphus when compared to uncoated E. coli cells. Based on the soft-particle Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, an energy barrier existed between uncoated E. coli cells and algal cells, whereas the PEI coating on E. coli cells eliminated the energy barrier, thereby the biocoagulation was significantly improved. Overall, this work presented groundwork toward the potential use of bacterial biomass for algal harvesting from water. PMID:24926598

  13. Evaluation of target efficiencies for solid-liquid separation steps in biofuels production.

    PubMed

    Kochergin, Vadim; Miller, Keith

    2011-01-01

    Development of liquid biofuels has entered a new phase of large scale pilot demonstration. A number of plants that are in operation or under construction face the task of addressing the engineering challenges of creating a viable plant design, scaling up and optimizing various unit operations. It is well-known that separation technologies account for 50-70% of both capital and operating cost. Additionally, reduction of environmental impact creates technological challenges that increase project cost without adding to the bottom line. Different technologies vary in terms of selection of unit operations; however, solid-liquid separations are likely to be a major contributor to the overall project cost. Despite the differences in pretreatment approaches, similar challenges arise for solid-liquid separation unit operations. A typical process for ethanol production from biomass includes several solid-liquid separation steps, depending on which particular stream is targeted for downstream processing. The nature of biomass-derived materials makes it either difficult or uneconomical to accomplish complete separation in a single step. Therefore, setting realistic efficiency targets for solid-liquid separations is an important task that influences overall process recovery and economics. Experimental data will be presented showing typical characteristics for pretreated cane bagasse at various stages of processing into cellulosic ethanol. Results of generic material balance calculations will be presented to illustrate the influence of separation target efficiencies on overall process recoveries and characteristics of waste streams. PMID:20607445

  14. Assessing methanotrophy and carbon fixation for biofuel production by Methanosarcina acetivorans

    DOE PAGESBeta

    Nazem-Bokaee, Hadi; Gopalakrishnan, Saratram; Ferry, James G.; Wood, Thomas K.; Maranas, Costas D.

    2016-01-17

    Methanosarcina acetivorans is a model archaeon with renewed interest due to its unique reversible methane production pathways. However, the mechanism and relevant pathways implicated in (co)utilizing novel carbon substrates in this organism are still not fully understood. This paper provides a comprehensive inventory of thermodynamically feasible routes for anaerobic methane oxidation, co-reactant utilization, and maximum carbon yields of major biofuel candidates by M. acetivorans. Here, an updated genome-scale metabolic model of M. acetivorans is introduced (iMAC868 containing 868 genes, 845 reactions, and 718 metabolites) by integrating information from two previously reconstructed metabolic models (i.e., iVS941 and iMB745), modifying 17 reactions,more » adding 24 new reactions, and revising 64 gene-proteinreaction associations based on newly available information. The new model establishes improved predictions of growth yields on native substrates and is capable of correctly predicting the knockout outcomes for 27 out of 28 gene deletion mutants. By tracing a bifurcated electron flow mechanism, the iMAC868 model predicts thermodynamically feasible (co)utilization pathway of methane and bicarbonate using various terminal electron acceptors through the reversal of the aceticlastic pathway. In conclusion, this effort paves the way in informing the search for thermodynamically feasible ways of (co)utilizing novel carbon substrates in the domain Archaea.« less

  15. IPAD products and implications for the future

    NASA Technical Reports Server (NTRS)

    Miller, R. E., Jr.

    1980-01-01

    The betterment of productivity through the improvement of product quality and the reduction of cost is addressed. Productivity improvement is sought through (1) reduction of required resources, (2) improved ask results through the management of such saved resources, (3) reduced downstream costs through manufacturing-oriented engineering, and (4) lowered risks in the making of product design decisions. The IPAD products are both hardware architecture and software distributed over a number of heterogeneous computers in this architecture. These IPAD products are described in terms of capability and engineering usefulness. The future implications of state-of-the-art IPAD hardware and software architectures are discussed in terms of their impact on the functions and on structures of organizations concerned with creating products.

  16. Livestock production: recent trends, future prospects

    PubMed Central

    Thornton, Philip K.

    2010-01-01

    The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades. PMID:20713389

  17. Genomic Evaluation of Thermoanaerobacter spp. for the Construction of Designer Co-Cultures to Improve Lignocellulosic Biofuel Production

    PubMed Central

    Verbeke, Tobin J.; Zhang, Xiangli; Henrissat, Bernard; Spicer, Vic; Rydzak, Thomas; Krokhin, Oleg V.; Fristensky, Brian; Levin, David B.; Sparling, Richard

    2013-01-01

    The microbial production of ethanol from lignocellulosic biomass is a multi-component process that involves biomass hydrolysis, carbohydrate transport and utilization, and finally, the production of ethanol. Strains of the genus Thermoanaerobacter have been studied for decades due to their innate abilities to produce comparatively high ethanol yields from hemicellulose constituent sugars. However, their inability to hydrolyze cellulose, limits their usefulness in lignocellulosic biofuel production. As such, co-culturing Thermoanaerobacter spp. with cellulolytic organisms is a plausible approach to improving lignocellulose conversion efficiencies and yields of biofuels. To evaluate native lignocellulosic ethanol production capacities relative to competing fermentative end-products, comparative genomic analysis of 11 sequenced Thermoanaerobacter strains, including a de novo genome, Thermoanaerobacter thermohydrosulfuricus WC1, was conducted. Analysis was specifically focused on the genomic potential for each strain to address all aspects of ethanol production mentioned through a consolidated bioprocessing approach. Whole genome functional annotation analysis identified three distinct clades within the genus. The genomes of Clade 1 strains encode the fewest extracellular carbohydrate active enzymes and also show the least diversity in terms of lignocellulose relevant carbohydrate utilization pathways. However, these same strains reportedly are capable of directing a higher proportion of their total carbon flux towards ethanol, rather than non-biofuel end-products, than other Thermoanaerobacter strains. Strains in Clade 2 show the greatest diversity in terms of lignocellulose hydrolysis and utilization, but proportionately produce more non-ethanol end-products than Clade 1 strains. Strains in Clade 3, in which T. thermohydrosulfuricus WC1 is included, show mid-range potential for lignocellulose hydrolysis and utilization, but also exhibit extensive divergence from both Clade 1 and Clade 2 strains in terms of cellular energetics. The potential implications regarding strain selection and suitability for industrial ethanol production through a consolidated bioprocessing co-culturing approach are examined throughout the manuscript. PMID:23555660

  18. Effect of pre-treatments on the production of biofuels from Phaeodactylum tricornutum.

    PubMed

    Caporgno, M P; Olkiewicz, M; Torras, C; Salvadó, J; Clavero, E; Bengoa, C

    2016-07-15

    Several characteristics make Phaeodactylum tricornutum potential candidate for biofuels production such as methane and biodiesel. For this reason, some alternatives are evaluated in this manuscript to improve the conversion of this microalgae into methane. One of these alternatives is the addition of sewage sludge to Phaeodactylum tricornutum for anaerobic co-digestion. Although the co-digestion resulted in lack of synergy, the absence of inhibition indicated that both substrates could be co-digested under certain circumstances, for example if microalgae are cultivated for wastewater treatment purposes. The extraction of lipids using organic solvents has been evaluated for biodiesel production but also as a pre-treatment for anaerobic digestion. The results revealed that the type of solvent influences lipid and biodiesel yields. The high polarity of the mixture methanol/hexane increased the lipid and the biodiesel yields from 10 ± 1 to 53 ± 2 gLipids/100 gVS and from 7 ± 1 to 11 ± 1 gBiodiesel/100 gVS compared with hexane. However, none of these solvents affected the composition of biodiesel. Regarding the methane production after the extraction, it yielded 257 ± 8 and 180 ± 6 mLCH4/gVS from lipid-extracted P. tricornutum using hexane and methanol/hexane respectively. The methane production from the raw microalga was 258 ± 5 mLCH4/gVS in the same experiment. The difference in methane production, mainly after the extraction with methanol/hexane, was a consequence of the changes in the composition of the microalgae after extraction. The extraction did not influence the biodegradability. The ultrasonic pre-treatment prior anaerobic digestion completely disrupted the microalgae cells, but the solubilisation of the organic fraction was scarce (<9.5%). The methane production from pre-treated samples was barely 10-11% higher than the obtained from non pre-treated samples, indicating that the refractory nature of the organic fraction in P. tricornutum is the main obstacle for the methane production. PMID:27107392

  19. Agrigenomics for Microalgal Biofuel Production: An Overview of Various Bioinformatics Resources and Recent Studies to Link OMICS to Bioenergy and Bioeconomy

    PubMed Central

    Misra, Namrata; Parida, Bikram Kumar

    2013-01-01

    Abstract Microalgal biofuels offer great promise in contributing to the growing global demand for alternative sources of renewable energy. However, to make algae-based fuels cost competitive with petroleum, lipid production capabilities of microalgae need to improve substantially. Recent progress in algal genomics, in conjunction with other “omic” approaches, has accelerated the ability to identify metabolic pathways and genes that are potential targets in the development of genetically engineered microalgal strains with optimum lipid content. In this review, we summarize the current bioeconomic status of global biofuel feedstocks with particular reference to the role of “omics” in optimizing sustainable biofuel production. We also provide an overview of the various databases and bioinformatics resources available to gain a more complete understanding of lipid metabolism across algal species, along with the recent contributions of “omic” approaches in the metabolic pathway studies for microalgal biofuel production. PMID:24044362

  20. Agrigenomics for microalgal biofuel production: an overview of various bioinformatics resources and recent studies to link OMICS to bioenergy and bioeconomy.

    PubMed

    Misra, Namrata; Panda, Prasanna Kumar; Parida, Bikram Kumar

    2013-11-01

    Microalgal biofuels offer great promise in contributing to the growing global demand for alternative sources of renewable energy. However, to make algae-based fuels cost competitive with petroleum, lipid production capabilities of microalgae need to improve substantially. Recent progress in algal genomics, in conjunction with other "omic" approaches, has accelerated the ability to identify metabolic pathways and genes that are potential targets in the development of genetically engineered microalgal strains with optimum lipid content. In this review, we summarize the current bioeconomic status of global biofuel feedstocks with particular reference to the role of "omics" in optimizing sustainable biofuel production. We also provide an overview of the various databases and bioinformatics resources available to gain a more complete understanding of lipid metabolism across algal species, along with the recent contributions of "omic" approaches in the metabolic pathway studies for microalgal biofuel production. PMID:24044362

  1. Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes

    PubMed Central

    Landis, Douglas A.; Gardiner, Mary M.; van der Werf, Wopke; Swinton, Scott M.

    2008-01-01

    Increased demand for corn grain as an ethanol feedstock is altering U.S. agricultural landscapes and the ecosystem services they provide. From 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. Biological control of insects is an ecosystem service that is strongly influenced by local landscape structure. Here, we estimate the value of natural biological control of the soybean aphid, a major pest in agricultural landscapes, and the economic impacts of reduced biocontrol caused by increased corn production in 4 U.S. states (Iowa, Michigan, Minnesota, and Wisconsin). For producers who use an integrated pest management strategy including insecticides as needed, natural suppression of soybean aphid in soybean is worth an average of $33 ha−1. At 2007–2008 prices these services are worth at least $239 million y−1 in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversity, altering the supply of aphid natural enemies to soybean fields and reducing biocontrol services by 24%. This loss of biocontrol services cost soybean producers in these states an estimated $58 million y−1 in reduced yield and increased pesticide use. For producers who rely solely on biological control, the value of lost services is much greater. These findings from a single pest in 1 crop suggest that the value of biocontrol services to the U.S. economy may be underestimated. Furthermore, we suggest that development of cellulosic ethanol production processes that use a variety of feedstocks could foster increased diversity in agricultural landscapes and enhance arthropod-mediated ecosystem services. PMID:19075234

  2. Carbon Calculator for Land Use Change from Biofuels Production (CCLUB). Users' manual and technical documentation.

    SciTech Connect

    Mueller, S; Dunn, JB; Wang, M

    2012-06-07

    The Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) calculates carbon emissions from land use change (LUC) for four different ethanol production pathways including corn grain ethanol and cellulosic ethanol from corn stover, miscanthus, and switchgrass. This document discusses the version of CCLUB released May 31, 2012 which includes corn, as did the previous CCLUB version, and three cellulosic feedstocks: corn stover, miscanthus, and switchgrass. CCLUB calculations are based upon two data sets: land change areas and above- and below-ground carbon content. Table 1 identifies where these data are stored and used within the CCLUB model, which is built in MS Excel. Land change area data is from Purdue University's Global Trade Analysis Project (GTAP) model, a computable general equilibrium (CGE) economic model. Section 2 describes the GTAP data CCLUB uses and how these data were modified to reflect shrubland transitions. Feedstock- and spatially-explicit below-ground carbon content data for the United States were generated with a surrogate model for CENTURY's soil organic carbon sub-model (Kwon and Hudson 2010) as described in Section 3. CENTURY is a soil organic matter model developed by Parton et al. (1987). The previous CCLUB version used more coarse domestic carbon emission factors. Above-ground non-soil carbon content data for forest ecosystems was sourced from the USDA/NCIAS Carbon Online Estimator (COLE) as explained in Section 4. We discuss emission factors used for calculation of international greenhouse gas (GHG) emissions in Section 5. Temporal issues associated with modeling LUC emissions are the topic of Section 6. Finally, in Section 7 we provide a step-by-step guide to using CCLUB and obtaining results.

  3. Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes.

    PubMed

    Landis, Douglas A; Gardiner, Mary M; van der Werf, Wopke; Swinton, Scott M

    2008-12-23

    Increased demand for corn grain as an ethanol feedstock is altering U.S. agricultural landscapes and the ecosystem services they provide. From 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. Biological control of insects is an ecosystem service that is strongly influenced by local landscape structure. Here, we estimate the value of natural biological control of the soybean aphid, a major pest in agricultural landscapes, and the economic impacts of reduced biocontrol caused by increased corn production in 4 U.S. states (Iowa, Michigan, Minnesota, and Wisconsin). For producers who use an integrated pest management strategy including insecticides as needed, natural suppression of soybean aphid in soybean is worth an average of $33 ha(-1). At 2007-2008 prices these services are worth at least $239 million y(-1) in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversity, altering the supply of aphid natural enemies to soybean fields and reducing biocontrol services by 24%. This loss of biocontrol services cost soybean producers in these states an estimated $58 million y(-1) in reduced yield and increased pesticide use. For producers who rely solely on biological control, the value of lost services is much greater. These findings from a single pest in 1 crop suggest that the value of biocontrol services to the U.S. economy may be underestimated. Furthermore, we suggest that development of cellulosic ethanol production processes that use a variety of feedstocks could foster increased diversity in agricultural landscapes and enhance arthropod-mediated ecosystem services. PMID:19075234

  4. Fuel for the Future: Development of New Fuels, e.g. Biofuels

    NASA Astrophysics Data System (ADS)

    Sørensen, Gitte; Sørensen, Ketil Bernt; Hansen, Hans Ove; Nygaard, Sune D.

    Whether we like it or not, climate change is to some extent affiliated with the emission of green house gasses, and specifically CO2 emissions, which are rising due to the global increased use of fossil fuels. As a result, political enthusiasm is high when it comes to implementing new initiatives aimed at better protection of the global environment. However, environmental concerns are just one aspect of the issues associated with the use of fossil fuels, since fossil fuels are a natural reserve and, therefore, a limited resource. Prognoses vary, but within the next decades the fossil fuel reserves will be exhausted leading to reduced oil production, rising oil prices, and the risk of international bellicose conflicts caused by adverse national interests. Additionally, fossil fuel as a natural reserve is unevenly distributed, meaning that a few countries possess the main energy reserve of the entire world. The incorporation of alternatives to fossil fuel into the existing fuel infrastructure is currently under intense development in the Western world, both to cut the oil dependency and to counter the depletion of oil reserves. This political enthusiasm to decrease the use of fossil fuel is emphasised by the fact that according to the International Energy Agency (IEA) more than 80% of the global primary energy consumption in 2007 accounts from fossil fuels and half of this is oil. More than 60% of the oil is used in the transport sector.

  5. Spatial Optimization of Cropping Pattern in an Agricultural Watershed for Food and Biofuel Production with Minimum Downstream Pollution

    NASA Astrophysics Data System (ADS)

    Pv, F.; Sudheer, K.; Chaubey, I.; RAJ, C.; Her, Y.

    2013-05-01

    Biofuel is considered to be a viable alternative to meet the increasing fuel demand, and therefore many countries are promoting agricultural activities that help increase production of raw material for biofuel production. Mostly, the biofuel is produced from grain based crops such as Corn, and it apparently create a shortage in food grains. Consequently, there have been regulations to limit the ethanol production from grains, and to use cellulosic crops as raw material for biofuel production. However, cultivation of such cellulosic crops may have different effects on water quality in the watershed. Corn stover, one of the potential cellulosic materials, when removed from the agricultural field for biofuel production, causes a decrease in the organic nutrients in the field. This results in increased use of pesticides and fertilizers which in turn affect the downstream water quality due to leaching of the chemicals. On the contrary, planting less fertilizer-intensive cellulosic crops, like Switch Grass and Miscanthus, is expected to reduce the pollutant loadings from the watershed. Therefore, an ecologically viable land use scenario would be a mixed cropping of grain crops and cellulosic crops, that meet the demand for food and biofuel without compromising on the downstream water quality. Such cropping pattern can be arrived through a simulation-optimization framework. Mathematical models can be employed to evaluate various management scenarios related to crop production and to assess its impact on water quality. Soil and Water Assessment Tool (SWAT) model is one of the most widely used models in this context. SWAT can simulate the water and nutrient cycles, and also quantify the long-term impacts of land management practices, in a watershed. This model can therefore help take decisions regarding the type of cropping and management practices to be adopted in the watershed such that the water quality in the rivers is maintained at acceptable level. In this study, it is proposed to link SWAT model with an optimization algorithm, whose objective is to identify the optimal cropping pattern that results in maximum biomass production for biofuel generation as well as a minimum guaranteed amount of grain production. The optimal allocation ensures that the downstream water quality in the river is within a desirable limit. The study employed probabilistic information in order to address the uncertainty in model simulations. The residual variance of the model is used to transform the deterministic simulations in to probabilistic information. The proposed framework is illustrated using data pertaining to an agricultural watershed in the USA. The preliminary results of the study are encouraging and suggest that an appropriate combination of Corn, Soyabean, Miscanthus, Switch Grass and Pasture land can be arrived at through the developed framework. The placement of Miscanthus and Switch Grass in the watershed help improve the downstream water quality, while Corn and Soyabean makes it deteriorated. The spatial allocation of these crops therefore certainly plays a major role in the downstream water quality.

  6. Biofuel Ethanol Transport Risk

    EPA Science Inventory

    Ethanol production has increased rapidly over the last 10 years and many communities lack awareness of the increased and growing extent of biofuel transportation through their jurisdictions. These communities and their emergency responders may not have the information and resour...

  7. De Novo Transcriptomic Analysis of an Oleaginous Microalga: Pathway Description and Gene Discovery for Production of Next-Generation Biofuels

    PubMed Central

    Wan, LingLin; Han, Juan; Sang, Min; Li, AiFen; Wu, Hong; Yin, ShunJi; Zhang, ChengWu

    2012-01-01

    Background Eustigmatos cf. polyphem is a yellow-green unicellular soil microalga belonging to the eustimatophyte with high biomass and considerable production of triacylglycerols (TAGs) for biofuels, which is thus referred to as an oleaginous microalga. The paucity of microalgae genome sequences, however, limits development of gene-based biofuel feedstock optimization studies. Here we describe the sequencing and de novo transcriptome assembly for a non-model microalgae species, E. cf. polyphem, and identify pathways and genes of importance related to biofuel production. Results We performed the de novo assembly of E. cf. polyphem transcriptome using Illumina paired-end sequencing technology. In a single run, we produced 29,199,432 sequencing reads corresponding to 2.33 Gb total nucleotides. These reads were assembled into 75,632 unigenes with a mean size of 503 bp and an N50 of 663 bp, ranging from 100 bp to >3,000 bp. Assembled unigenes were subjected to BLAST similarity searches and annotated with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology identifiers. These analyses identified the majority of carbohydrate, fatty acids, TAG and carotenoids biosynthesis and catabolism pathways in E. cf. polyphem. Conclusions Our data provides the construction of metabolic pathways involved in the biosynthesis and catabolism of carbohydrate, fatty acids, TAG and carotenoids in E. cf. polyphem and provides a foundation for the molecular genetics and functional genomics required to direct metabolic engineering efforts that seek to enhance the quantity and character of microalgae-based biofuel feedstock. PMID:22536352

  8. Liquid biofuels - can they meet our expectations?

    NASA Astrophysics Data System (ADS)

    Glatzel, G.

    2012-04-01

    Liquid biofuels are one of the options for reducing the emission of greenhouse gases and the dependence on fossil fuels. This is reflected in the DIRECTIVE 2003/30/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL on the promotion of the use of biofuels or other renewable fuels for transport. The promotion of E10, an automotive fuel containing 10 percent bioethanol, is based on this directive. At present almost all bioethanol is produced from agricultural crops such as maize, corn or sugar beet and sugar cane in suitable climates. In view of shortages and rising prices of food, in particular in developing countries, the use of food and feed crops for biofuel production is increasingly criticized. Alternative sources of biomass are perennial grasses and wood, whose cellulose fraction can be converted to alcohol by the so called "second generation" processes, which seem to be close to commercial deployment. The use of the total plant biomass increases the biofuel yield per hectare as compared to conventional crops. Of special interest for biofuel production is woody biomass from forests as this avoids competition with food production on arable land. Historically woody biomass was for millennia the predominant source of thermal energy. Before fossil fuels came into use, up to 80 percent of a forest was used for fuel wood, charcoal and raw materials such as potash for trade and industry. Now forests are managed to yield up to 80 percent of high grade timber for the wood industry. Replacing sophisticatedly managed forests by fast growing biofuel plantations could make economic sense for land owners when a protected market is guaranteed by politics, because biofuel plantations would be highly mechanized and cheap to operate, even if costs for certified planting material and fertilizer are added. For forest owners the decision to clear existing long rotation forests for biofuel plantations would still be weighty because of the extended time of decades required to rebuild a timber forest if alternative fuel sources would outcompete biofuels in the future. Because second generation bioethanol plants are technically complex and will require substantial amounts of biomass - at least at current perception - the impact of large scale conversion of arable and forests to biofuel plantations on biodiversity, ground water, rural communities, tourism as well as traffic and transport, just to mention a few, must be considered. Another factor is storability of biomass. Whole plant and woody biomass is much more difficult to store than grains and a steady flux from the plantation to the mill might be difficult to sustain under adverse weather conditions.

  9. Biofuels: balancing risks and rewards

    PubMed Central

    Thornley, Patricia; Gilbert, Paul

    2013-01-01

    This paper describes a framework that can be used to evaluate the environmental risks and benefits associated with biofuel production. It uses the example of biodiesel produced from Argentinean soy to show how such a framework can be used to conceptualize trade-offs between different environmental, social and economic impacts of biofuel production. Results showing the greenhouse-gas savings and overall life-cycle impact of different ‘soy-biodiesel’ production methods are presented. These impacts and the significance of uncertainty in overall assessments of key parameters, such as greenhouse-gas savings, are discussed. It is shown that, even where sufficient knowledge exists to be able to quantify these impacts, the sustainability of supply of a particular biofuel is inextricably linked to values and ethical judgements. However, tailoring certification efforts to the issues that are most likely to make a significant difference to the overall sustainability could improve the effectiveness of certification efforts. The potential for a framework to guide and focus certification efforts is discussed and future research and policy priorities suggested. PMID:24427513

  10. Satellite-based assessment of water requirement for biofuel feedstock production in Maui, Hawaii

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Anderson, R. G.; Wang, D.

    2012-12-01

    Water availability is one of the limiting factors for sustainable production of biofuel crops. A common method for determining crop water requirement is to multiply daily potential evapotranspiration (ETo) calculated from meteorological parameters by a crop coefficient (Kc) to obtain actual crop evapotranspiration (ETc). Remote sensing data can provide dynamic Kc values that better reflect plant water use. In this study, an algorithm is being developed to estimate sugarcane Kc using normalized difference vegetation index (NDVI) obtained from Landsat 7 satellite images. Crop canopy cover was measured with a handheld multispectral camera from two sugarcane fields at the Hawaiian Commercial & Sugar Company (HC&S) plantation during the Landsat 7 satellite overpass days. An Eddy Covariance (EC) tower system was set up within each of these two fields and gathered EC flux at a 30-minute interval. Reference evapotranspiration was calculated from the network of automated weather stations at HC&S plantation using a modified Penman equation. Crop canopy cover was highly correlated with satellite NDVI values. A linear relationship between NDVI and measured Kc was obtained. Satellite -based ETc maps of HC&S plantation were developed using the NDVI-based Kc values and reference ET from HC&S weather station network. The satellite-based ETc was compared and validated with field measurements of ET using Eddy Covariance tower. A series of satellite-based ETc maps were developed to indicate the water demand of sugarcane plants at HC&S plantation. These results validate the use of satellite imagery as a tool for estimation of ET of sugarcane plants in Maui, Hawaii.

  11. Biofuels combustion.

    PubMed

    Westbrook, Charles K

    2013-01-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly. PMID:23298249

  12. Biofuels Combustion

    NASA Astrophysics Data System (ADS)

    Westbrook, Charles K.

    2013-04-01

    This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

  13. N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels

    NASA Astrophysics Data System (ADS)

    Crutzen, P. J.; Mosier, A. R.; Smith, K. A.; Winiwarter, W.

    2008-01-01

    The relationship, on a global basis, between the amount of N fixed by chemical, biological or atmospheric processes entering the terrestrial biosphere, and the total emission of nitrous oxide (N2O), has been re-examined, using known global atmospheric removal rates and concentration growth of N2O as a proxy for overall emissions. For both the pre-industrial period and in recent times, after taking into account the large-scale changes in synthetic N fertiliser production, we find an overall conversion factor of 3-5% from newly fixed N to N2O-N. We assume the same factor to be valid for biofuel production systems. It is covered only in part by the default conversion factor for "direct" emissions from agricultural crop lands (1%) estimated by IPCC (2006), and the default factors for the "indirect" emissions (following volatilization/deposition and leaching/runoff of N: 0.35-0.45%) cited therein. However, as we show in the paper, when additional emissions included in the IPCC methodology, e.g. those from livestock production, are included, the total may not be inconsistent with that given by our "top-down" method. When the extra N2O emission from biofuel production is calculated in "CO2-equivalent" global warming terms, and compared with the quasi-cooling effect of "saving" emissions of fossil fuel derived CO2, the outcome is that the production of commonly used biofuels, such as biodiesel from rapeseed and bioethanol from corn (maize), depending on N fertilizer uptake efficiency by the plants, can contribute as much or more to global warming by N2O emissions than cooling by fossil fuel savings. Crops with less N demand, such as grasses and woody coppice species, have more favourable climate impacts. This analysis only considers the conversion of biomass to biofuel. It does not take into account the use of fossil fuel on the farms and for fertilizer and pesticide production, but it also neglects the production of useful co-products. Both factors partially compensate each other. This needs to be analyzed in a full life cycle assessment.

  14. Assessment of a Novel Algal Strain Chlamydomonas debaryana NIREMACC03 for Mass Cultivation, Biofuels Production and Kinetic Studies.

    PubMed

    Mishra, Sanjeev; Singh, Neetu; Sarma, Anil Kumar

    2015-08-01

    A novel microalgae strain Chlamydomonas debaryana (KJ210856) was isolated from a freshwater lake of Punjab, India, and cultivated considering climatic sustainability and inherent adaptability concern. C. debaryana was grown in a 30-L indoor photobioreactor to study the mass cultivation prospect and biofuel potential. Physicochemical characterization of biomass and the lipid was performed with effect to nitrogen stress. It showed a higher biomass yield (1.58 ± 0.02 g L(-1), dry weight) and twofold increase in lipid yield (552.78 ± 9 mg L(-1)) with 34.2 ± 0.19 % lipid content under nitrogen deficient condition. Strikingly, increase in triglycerides achieved with nitrogen depletion containing over 96 % of total fatty acids (C 14, C 16, and C 18). Proximate and ultimate analysis suggested the presence of relatively higher volatile matter and carbon-hydrogen ratio. Furthermore, lower moisture and ash content signified C. debaryana biomass has promising features towards biofuel applications. The pyrolytic behavior of the whole biomass was also studied using thermogravimetric analyzer (TGA) and kinetic parameters were estimated using different methods. Promising growth rate and lipid yield leading to feasible biofuel feed stock production in indoor photobioreactor along with autosediment potential of cells validates C. debaryana NIREMACC03, a potential strain for mass cultivation. PMID:26093613

  15. Tradeoffs and Synergies between biofuel production and large solar infrastructure in deserts.

    PubMed

    Ravi, Sujith; Lobell, David B; Field, Christopher B

    2014-01-01

    Solar energy installations in deserts are on the rise, fueled by technological advances and policy changes. Deserts, with a combination of high solar radiation and availability of large areas unusable for crop production are ideal locations for large solar installations. However, for efficient power generation, solar infrastructures use large amounts of water for construction and operation. We investigated the water use and greenhouse gas (GHG) emissions associated with solar installations in North American deserts in comparison to agave-based biofuel production, another widely promoted potential energy source from arid systems. We determined the uncertainty in our analysis by a Monte Carlo approach that varied the most important parameters, as determined by sensitivity analysis. We considered the uncertainty in our estimates as a result of variations in the number of solar modules ha(-1), module efficiency, number of agave plants ha(-1), and overall sugar conversion efficiency for agave. Further, we considered the uncertainty in revenue and returns as a result of variations in the wholesale price of electricity and installation cost of solar photovoltaic (PV), wholesale price of agave ethanol, and cost of agave cultivation and ethanol processing. The life-cycle analyses show that energy outputs and GHG offsets from solar PV systems, mean energy output of 2405 GJ ha(-1) year(-1) (5 and 95% quantile values of 1940-2920) and mean GHG offsets of 464 Mg of CO2 equiv ha(-1) year(-1) (375-562), are much larger than agave, mean energy output from 206 (171-243) to 61 (50-71) GJ ha(-1) year(-1) and mean GHG offsets from 18 (14-22) to 4.6 (3.7-5.5) Mg of CO2 equiv ha(-1) year(-1), depending upon the yield scenario of agave. Importantly though, water inputs for cleaning solar panels and dust suppression are similar to amounts required for annual agave growth, suggesting the possibility of integrating the two systems to maximize the efficiency of land and water use to produce both electricity and liquid fuel. A life-cycle analysis of a hypothetical colocation indicated higher returns per m(3) of water used than either system alone. Water requirements for energy production were 0.22 L MJ(-1) (0.28-0.19) and 0.42 L MJ(-1) (0.52-0.35) for solar PV-agave (baseline yield) and solar PV-agave (high yield), respectively. Even though colocation may not be practical in all locations, in some water-limited areas, colocated solar PV-agave systems may provide attractive economic incentives in addition to efficient land and water use. PMID:24467248

  16. Energy crops for biofuel feedstocks: facts and recent patents on genetic manipulation to improve biofuel crops.

    PubMed

    Kumar, Suresh

    2013-12-01

    Burning fossil-fuels to meet the global energy requirements by human being has intensified the concerns of increasing concentrations of greenhouse gases. Therefore, serious efforts are required to develop nonfossil-based renewable energy sources. Plants are more efficient in utilizing solar energy to convert it into biomass which can be used as feedstocks for biofuel production. Hence with the increasing demands of energy and the needs of cost-effective, sustainable production of fuels, it has become necessary to switch over to plant biomass as a renewable source of energy. Biofuels derived from more sustainable biological materials such as lignocellulosic plant residues, considered as second generation biofuels, are more dependable. However, there are technical challenges such as pretreatment and hydrolysis of lignocellulosic biomass to convert it into fermentable sugars. Plant genetic engineering has already proven its potential in modifying cell wall composition of plants for enhancing the efficiency of biofuel production. Interest and potential in the area are very much evident from the growing number of patents in the recent years on the subject. In this review, recent trends in genetic engineering of energy crops for biofuel production have been introduced, and strategies for the future developments have been discussed. PMID:24456235

  17. First generation biofuels compete.

    PubMed

    Martin, Marshall A

    2010-11-30

    Rising petroleum prices during 2005-2008, and passage of the 2007 U.S. Energy Independence and Security Act with a renewable fuel standard of 36 billion gallons of biofuels by 2022, encouraged massive investments in U.S. ethanol plants. Consequently, corn demand increased dramatically and prices tripled. This created a strong positive correlation between petroleum, corn, and food prices resulting in an outcry from U.S. consumers and livestock producers, and food riots in several developing countries. Other factors contributed to higher grain and food prices. Economic growth, especially in Asia, and a weaker U.S. dollar encouraged U.S. grain exports. Investors shifted funds into the commodity's future markets. Higher fuel costs for food processing and transportation put upward pressure on retail food prices. From mid-2008 to mid-2009, petroleum prices fell, the U.S. dollar strengthened, and the world economy entered a serious recession with high unemployment, housing market foreclosures, collapse of the stock market, reduced global trade, and a decline in durable goods and food purchases. Agricultural commodity prices declined about 50%. Biotechnology has had modest impacts on the biofuel sector. Seed corn with traits that help control insects and weeds has been widely adopted by U.S. farmers. Genetically engineered enzymes have reduced ethanol production costs and increased conversion efficiency. PMID:20601265

  18. Analysis of advanced biofuels.

    SciTech Connect

    Dec, John E.; Taatjes, Craig A.; Welz, Oliver; Yang, Yi

    2010-09-01

    Long chain alcohols possess major advantages over ethanol as bio-components for gasoline, including higher energy content, better engine compatibility, and less water solubility. Rapid developments in biofuel technology have made it possible to produce C{sub 4}-C{sub 5} alcohols efficiently. These higher alcohols could significantly expand the biofuel content and potentially replace ethanol in future gasoline mixtures. This study characterizes some fundamental properties of a C{sub 5} alcohol, isopentanol, as a fuel for homogeneous-charge compression-ignition (HCCI) engines. Wide ranges of engine speed, intake temperature, intake pressure, and equivalence ratio are investigated. The elementary autoignition reactions of isopentanol is investigated by analyzing product formation from laser-photolytic Cl-initiated isopentanol oxidation. Carbon-carbon bond-scission reactions in the low-temperature oxidation chemistry may provide an explanation for the intermediate-temperature heat release observed in the engine experiments. Overall, the results indicate that isopentanol has a good potential as a HCCI fuel, either in neat form or in blend with gasoline.

  19. Butanol (a superior biofuel) production from agricultural residues (renewable biomass): recent progress in technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article reviews bioconversion of plant materials such as wheat straw (WS), corn stover (CS), barley straw (BS), and switchgrass (SG) to butanol and process technology that converts these materials into this superior biofuel. Successful fermentation of low value WS makes butanol fermentation ec...

  20. Production of Advanced Biofuels via Liquefaction - Hydrothermal Liquefaction Reactor Design: April 5, 2013

    SciTech Connect

    Knorr, D.; Lukas, J.; Schoen, P.

    2013-11-01

    This report provides detailed reactor designs and capital costs, and operating cost estimates for the hydrothermal liquefaction reactor system, used for biomass-to-biofuels conversion, under development at Pacific Northwest National Laboratory. Five cases were developed and the costs associated with all cases ranged from $22 MM/year - $47 MM/year.

  1. Biofuel production from catalytic thermochemical conversion of animal manure and biomass

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of the research is to identify suitable catalysts to convert animal manure-based and biomass-based synthesis gas (syngas) to liquid biofuels such as mixed alcohols and hydrocarbons. Two pathways of catalytically converting syngas are investigated: (1)a two-step process involving the in...

  2. Biomass composition of perennial grasses for biofuel production in North Dakota, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Successful development of biofuels from biomass feedstocks depends on high yields and acceptable quality. We investigated the chemical composition of ten perennial grasses and mixtures across environments in North Dakota, USA. The contents of neutral detergent fiber, acid detergent fiber, acid deter...

  3. Impacts of the production and consumption of biofuels on stratospheric ozone

    NASA Astrophysics Data System (ADS)

    Revell, Laura E.; Bodeker, Greg E.; Huck, Petra E.; Williamson, Bryce E.

    2012-05-01

    Biofuels are becoming increasingly popular sources of renewable energy as economic pressures and environmental consequences encourage the use of alternatives to fossil fuels. However, growing crops destined for use as biofuels incurs large N2O emissions associated with the use of nitrogen-based fertilizers. Besides being a greenhouse gas, N2O is also the primary source of stratospheric NOx (NO + NO2) which leads to stratospheric ozone depletion. In this paper, the potential effects on the ozone layer of a large-scale shift away from fossil fuel use to biofuels consumption over the 21st century are examined. Under such a scenario, global-mean column ozone decreases by 2.6 DU between 2010 and 2100 in contrast to a 0.7 DU decrease under a control simulation (the IPCC SRES B1 scenario for greenhouse gases) and a 9.1 DU increase under the more commonly used SRES A1B scenario. Two factors cause the decrease in ozone in the biofuels simulation: 1) large N2O emissions lead to faster rates of the ozone-depleting NOx cycles and; 2) reduced CO2 emissions (due to less fossil fuel burning) lead to relatively less stratospheric cooling over the 21st century, which decreases ozone abundances. Reducing CO2 emissions while neglecting to reduce N2O emissions could therefore be damaging to the ozone layer.

  4. Managing the nitrogen cycle to reduce greenhouse gas emissions from crop production and biofuel expansion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The United States Renewable Fuel Standards (RFS2) established under the Energy Independence and Security Act of 2007 requires greenhouse gas (GHG) emissions to be lower for biofuels relative to fossil fuel combustion. However, there is an extensive debate in the literature about the potential to red...

  5. Soil Nitrous Oxide Emissions with Crop Production for Biofuel: Implications for Greenhouse Gas Mitigation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The growing biofuel commodity market for corn ethanol has the potential to reduce direct greenhouse gas (GHG) emissions associated with fossil fuel combustion in the US. However, projected increases in cropland to accommodate this energy-based commodity will also impact emissions of GHGs from soils...

  6. The Crossover Biorefinery in The Production of Liquid Biofuels and Bioderived Chemicals from Biomass: Emerging Technologies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Energy security and climate change imperatives require large-scale substitution of petroleum-based fuels over the next 15 years. Biofuels offer a diverse range of promising alternatives. Biomass is the only known, large-scale, renewable resource that can be converted into liquid fuels for transpor...

  7. Opportunities for Switzerland to Contribute to the Production of Algal Biofuels: the Hydrothermal Pathway to Bio-Methane.

    PubMed

    Bagnoud-Velásquez, Mariluz; Refardt, Dominik; Vuille, François; Ludwig, Christian

    2015-01-01

    Microalgae have a significant potential to be a sustainable source of fuel and thus are of interest in the transition to a sustainable energy system, in particular for resource-dependent countries such as Switzerland. Independence of fossil fuels, considerable reduction of CO(2) emissions, and abandoning nuclear energy may be possible with an integrated system approach including the sourcing of biofuels from different types of biomass. Today, a full carbon-to-fuel conversion is possible, and has been recently demonstrated with an advanced hydrothermal technology. The potential to develop algal biofuels is viewed as high thanks to the possibility they offer to uncouple bioenergy from food production. Nevertheless, technological breakthroughs must take place before commercial production becomes a reality, especially to meet the necessary cost savings and efficiency gains in the algae cultivation structure. In addition, an integrated management of waste resources to promote the nutrient recovery appears today as imperative to further improve the economic viability and the environmental sustainability of algal production. We provide here a review that includes the global technological status of both algae production and their conversion into biofuels in order to understand first the added value of algal energy in general before we focus on the potential of algae to contribute specifically to the Swiss energy system to the horizon 2050. In this respect, the hydrothermal conversion pathway of microalgal biomass into synthetic natural gas (SNG) is emphasized, as research into this technology has received considerable attention in Switzerland during the last decade. In addition, SNG is a particularly relevant fuel in the Swiss context due to the existing gas grid and to the opportunity it offers to cover a wide spectrum of energy applications, in particular cogeneration of heat and electricity or use as a transport fuel in the growing gas car fleet. PMID:26598406

  8. Methane production from glycolate excreting algae as a new concept in the production of biofuels.

    PubMed

    Günther, Anja; Jakob, Torsten; Goss, Reimund; König, Swetlana; Spindler, Daniel; Räbiger, Norbert; John, Saskia; Heithoff, Susanne; Fresewinkel, Mark; Posten, Clemens; Wilhelm, Christian

    2012-10-01

    It is the aim of the present work to introduce a new concept for methane production by the interaction of a glycolate-excreting alga (Chlamydomonas reinhardtii) and methanogenic microbes operating in separate compartments within one photobioreactor. This approach requires a minimum number of metabolic steps to convert light energy to methane thereby reducing the energetic and financial costs of biomass formation, harvest and refinement. In this feasibility study it is shown that the physiological limitations for sustained glycolate production can be circumvented by the use of C. reinhardtii mutants whose carbon concentrating mechanisms or glycolate dehydrogenase are suppressed. The results also demonstrate that methanogenic microbes are able to thrive on glycolate as single carbon source for a long time period, delivering biogas composed of CO(2)/methane with only very minor contamination. PMID:22850169

  9. Nutrient management studies in biofuel cropping systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research was conducted to determine the effect of nutrient management practices on biofuel crop production, and to evaluate long term effects of biofuel crop production on selected chemical, physical and microbiological properties. Experimental plots for research on biofuel crop production were esta...

  10. 17 CFR 41.41 - Security futures products accounts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY FUTURES PRODUCTS Customer Accounts and Margin Requirements § 41.41 Security futures products accounts. (a) Where security futures products may be held. (1) A person registered with the Commission as...

  11. Turning Bacteria into Fuel: Cyanobacteria Designed for Solar-Powered Highly Efficient Production of Biofuels

    SciTech Connect

    2010-01-01

    Broad Funding Opportunity Announcement Project: ASU is engineering a type of photosynthetic bacteria that efficiently produce fatty acids—a fuel precursor for biofuels. This type of bacteria, called Synechocystis, is already good at converting solar energy and carbon dioxide (CO2) into a type of fatty acid called lauric acid. ASU has modified the organism so it continuously converts sunlight and CO2 into fatty acids—overriding its natural tendency to use solar energy solely for cell growth and maximizing the solar-to-fuel conversion process. ASU’s approach is different because most biofuels research focuses on increasing cellular biomass and not on excreting fatty acids. The project has also identified a unique way to convert the harvested lauric acid into a fuel that can be easily blended with existing transportation fuels.

  12. Production of biofuels and biomolecules in the framework of circular economy: A regional case study.

    PubMed

    Jacquet, Nicolas; Haubruge, Eric; Richel, Aurore

    2015-12-01

    Faced to the economic and energetic context of our society, it is widely recognised that an alternative to fossil fuels and oil-based products will be needed in the nearest future. In this way, development of urban biorefinery could bring many solutions to this problem. Study of the implementation of urban biorefinery highlights two sustainable configurations that provide solutions to the Walloon context by promoting niche markets, developing circular economy and reducing transport of supply feedstock. First, autonomous urban biorefineries are proposed, which use biological waste for the production of added value molecules and/or finished products and are energetically self-sufficient. Second, integrated urban biorefineries, which benefit from an energy supply from a nearby industrial activity. In the Walloon economic context, these types of urban biorefineries could provide solutions by promoting niche markets, developing a circular economy model, optimise the transport of supply feedstock and contribute to the sustainable development. PMID:26574581

  13. An Assessment of Land Availability and Price in the Coterminous United States for Conversion to Algal Biofuel Production

    SciTech Connect

    Venteris, Erik R.; Skaggs, Richard; Coleman, Andre M.; Wigmosta, Mark S.

    2012-12-01

    Realistic economic assessment of land-intensive alternative energy sources (e.g., solar, wind, and biofuels) requires information on land availability and price. Accordingly, we created a comprehensive, national-scale model of these parameters for the United States. For algae-based biofuel, a minimum of 1.04E+05 km2 of land is needed to meet the 2022 EISA target of 2.1E+10 gallons year-1. We locate and quantify land types best converted. A data-driven model calculates the incentive to sell and a fair compensation value (real estate and lost future income). 1.02E+6 km2 of low slope, non-protected land is relatively available including croplands, pasture/ grazing, and forests. Within this total there is 2.64E+5 km2 of shrub and barren land available. The Federal government has 7.68E+4 km2 available for lease. Targeting unproductive lands minimizes land costs and impacts to existing industries. However, shrub and barren lands are limited by resources (water) and logistics, so land conversion requires careful consideration.

  14. Feasibility of filamentous fungi for biofuel production using hydrolysate from dilute sulfuric acid pretreatment of wheat straw

    PubMed Central

    2012-01-01

    Background Lipids produced from filamentous fungi show great promise for biofuel production, but a major limiting factor is the high production cost attributed to feedstock. Lignocellulosic biomass is a suitable feedstock for biofuel production due to its abundance and low value. However, very limited study has been performed on lipid production by culturing oleaginous fungi with lignocellulosic materials. Thus, identification of filamentous fungal strains capable of utilizing lignocellulosic hydrolysates for lipid accumulation is critical to improve the process and reduce the production cost. Results The growth performances of eleven filamentous fungi were investigated when cultured on glucose and xylose. Their dry cell weights, lipid contents and fatty acid profiles were determined. Six fungal strains with high lipid contents were selected to culture with the hydrolysate from dilute sulfuric acid pretreatment of wheat straw. The results showed that all the selected fungal strains were able to grow on both detoxified liquid hydrolysate (DLH) and non-detoxified liquid hydrolysate (NDLH). The highest lipid content of 39.4% was obtained by Mortierella isabellina on NDLH. In addition, NDLH with some precipitate could help M. isabellina form pellets with an average diameter of 0.11 mm. Conclusion This study demonstrated the possibility of fungal lipid production from lignocellulosic biomass. M. isabellina was the best lipid producer grown on lignocellulosic hydrolysates among the tested filamentous fungi, because it could not only accumulate oils with a high content by directly utilizing NDLH to simplify the fermentation process, but also form proper pellets to benefit the downstream harvesting. Considering the yield and cost, fungal lipids from lignocellulosic biomass are promising alternative sources for biodiesel production. PMID:22824058

  15. Production of an acetone-butanol-ethanol mixture from Clostridium acetobutylicum and its conversion to high-value biofuels.

    PubMed

    Sreekumar, Sanil; Baer, Zachary C; Pazhamalai, Anbarasan; Gunbas, Gorkem; Grippo, Adam; Blanch, Harvey W; Clark, Douglas S; Toste, F Dean

    2015-03-01

    Clostridium acetobutylicum is a bacterial species that ferments sugar to a mixture of organic solvents (acetone, butanol and ethanol). This protocol delineates a methodology to combine solventogenic clostridial fermentation and chemical catalysis via extractive fermentation for the production of biofuel blendstocks. Extractive fermentation of C. acetobutylicum is operated in fed-batch mode with a concentrated feed solution (500 grams per liter glucose and 50 grams per liter yeast extract) for 60 h, producing in excess of 40 g of solvents (acetone, butanol and ethanol) between the completely immiscible extractant and aqueous phases of the bioreactor. After distillation of the extractant phase, the acetone, butanol and ethanol mixture is upgraded to long-chain ketones over a palladium-hydrotalcite (Pd-HT) catalyst. This reaction is generally carried out in batch with a high-pressure Q-tube for 20 h at 250 °C. Following this protocol enables the production of ∼0.5 g of high-value biofuel precursors from a 1.7-g portion of fermentation solvents. PMID:25719271

  16. A New Biofuels Technology Blooms in Iowa

    SciTech Connect

    Mathisen, Todd; Bruch, Don

    2010-01-01

    Cellulosic biofuels made from agricultural waste have caught the attention of many farmers and could be the next revolution in renewable biofuels production. This video shows how an innovative technology that converts waste products from the corn harvest into renewable biofuels will help the U.S. produce billions of gallons of cellulosic biofuels over the coming decade. It will also stimulate local economies and reduce U.S. dependence on foreign oil.

  17. A New Biofuels Technology Blooms in Iowa

    ScienceCinema

    Mathisen, Todd; Bruch, Don;

    2013-05-29

    Cellulosic biofuels made from agricultural waste have caught the attention of many farmers and could be the next revolution in renewable biofuels production. This video shows how an innovative technology that converts waste products from the corn harvest into renewable biofuels will help the U.S. produce billions of gallons of cellulosic biofuels over the coming decade. It will also stimulate local economies and reduce U.S. dependence on foreign oil.

  18. 17 CFR 41.41 - Security futures products accounts.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY FUTURES PRODUCTS Customer Accounts and Margin Requirements § 41.41 Security futures...

  19. 17 CFR 41.41 - Security futures products accounts.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 1 2012-04-01 2012-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY FUTURES PRODUCTS Customer Accounts and Margin Requirements § 41.41 Security futures...

  20. 17 CFR 41.41 - Security futures products accounts.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY FUTURES PRODUCTS Customer Accounts and Margin Requirements § 41.41 Security futures...

  1. Biofuels and Biotechnology

    SciTech Connect

    Mielenz, Jonathan R

    2009-01-01

    The world obtains 86% of its energy from fossil fuels, 40% from petroleum, a majority of which goes to the transportation sector (www.IEA.gov). Well-recognized alternatives are fuels derived from renewable sources known as biofuels. There are a number of biofuels useful for transportation fuels, which include ethanol, biobutanol, mixed alcohols, biodiesel, and hydrogen. These biofuels are produced from biologically derived feedstock, almost exclusively being plant materials, either food or feed sources or inedible plant material called biomass. This chapter will discuss technologies for production of liquid transportation biofuels from renewable feedstocks, but hydrogen will not be included, as the production technology and infrastructure are not near term. In addition, a specific emphasis will be placed upon the research opportunities and potential for application of system biology tools to dissect and understand the biological processes central to production of these biofuels from biomass and biological materials. There are a number of technologies for production of each of these biofuels that range from fully mature processes such as grain-derived ethanol, emerging technology of ethanol form cellulose derived ethanol and immature processes such thermochemical conversion technologies and production of hydrogen all produced from renewable biological feedstocks. Conversion of biomass by various thermochemical and combustion technologies to produce thermochemical biodiesel or steam and electricity provide growing sources of bioenergy. However, these technologies are outside of the scope of this chapter, as is the use of biological processing for upgrading and conversion of fossil fuels. Therefore, this chapter will focus on the current status of production of biofuels produced from biological-derived feedstocks using biological processes. Regardless of the status of development of the biological process for production of the biofuels, each process can benefit from research and resulting development activities using the latest biological research tools and techniques. Among the most recently evolving research tools is what is collectively known as "omics" techniques such as genomics, transcriptomics, proteomics, metabolomics, and fluxomics, plus an ever growing omics word generation . These and other similar methodologies are central to understanding the interactive functioning of gene expression, resulting protein/enzyme production, which impacts the cellular metabolism, and carbon and metabolite flow. These system biology "omics" tools are beginning to be applied to understand and improve the biological processes involved in conversion of renewable plant and animal material to biofuels which will be discussed in this chapter.

  2. Microalgae biofuel potentials (review).

    PubMed

    Ghasemi, Y; Rasoul-Amini, S; Naseri, A T; Montazeri-Najafabady, N; Mobasher, M A; Dabbagh, F

    2012-01-01

    With the decrease of fossil based fuels and the environmental impact of them over the planet, it seems necessary to seek the sustainable sources of clean energy. Biofuels, is becoming a worldwide leader in the development of renewable energy resources. It is worthwhile to say that algal biofuel production is thought to help stabilize the concentration of carbon dioxide in the atmosphere and decrease global warming impacts. Also, among algal fuels' attractive characteristics, algal biodiesel is non toxic, with no sulfur, highly biodegradable and relatively harmless to the environment if spilled. Algae are capable of producing in excess of 30 times more oil per acre than corn and soybean crops. Currently, algal biofuel production has not been commercialized due to high costs associated with production, harvesting and oil extraction but the technology is progressing. Extensive research was conducted to determine the utilization of microalgae as an energy source and make algae oil production commercially viable. PMID:22586908

  3. Comparative energetics and kinetics of autotrophic lipid and starch metabolism in chlorophytic microalgae: implications for biomass and biofuel production

    PubMed Central

    2013-01-01

    Due to the growing need to provide alternatives to fossil fuels as efficiently, economically, and sustainably as possible there has been growing interest in improved biofuel production systems. Biofuels produced from microalgae are a particularly attractive option since microalgae have production potentials that exceed the best terrestrial crops by 2 to 10-fold. In addition, autotrophically grown microalgae can capture CO2 from point sources reducing direct atmospheric greenhouse gas emissions. The enhanced biomass production potential of algae is attributed in part to the fact that every cell is photosynthetic. Regardless, overall biological energy capture, conversion, and storage in microalgae are inefficient with less than 8% conversion of solar into chemical energy achieved. In this review, we examine the thermodynamic and kinetic constraints associated with the autotrophic conversion of inorganic carbon into storage carbohydrate and oil, the dominant energy storage products in Chlorophytic microalgae. We discuss how thermodynamic restrictions including the loss of fixed carbon during acetyl CoA synthesis reduce the efficiency of carbon accumulation in lipids. In addition, kinetic limitations, such as the coupling of proton to electron transfer during plastoquinone reduction and oxidation and the slow rates of CO2 fixation by Rubisco reduce photosynthetic efficiency. In some cases, these kinetic limitations have been overcome by massive increases in the numbers of effective catalytic sites, e.g. the high Rubisco levels (mM) in chloroplasts. But in other cases, including the slow rate of plastoquinol oxidation, there has been no compensatory increase in the abundance of catalytically limiting protein complexes. Significantly, we show that the energetic requirements for producing oil and starch relative to the recoverable energy stored in these molecules are very similar on a per carbon basis. Presently, the overall rates of starch and lipid synthesis in microalgae are very poorly characterized. Increased understanding of the kinetic constraints of lipid and starch synthesis, accumulation and turnover would facilitate the design of improved biomass production systems. PMID:24139286

  4. Biofuels: Report to Congress

    EPA Science Inventory

    Section 204 of the Energy Independence and Security Act of 2007 (EISA 2007) requires EPA to assess and report to Congress on the impacts to date and likely future impacts of the increased use of biofuels as required by the Clean Air Act, section 211(0). Environmental issues (...

  5. Forest Products Industry of the Future

    SciTech Connect

    Los Alamos Technical Associates, Inc

    2002-05-01

    Los Alamos Technical Associates, Inc (LATA) conducted an evaluation of the potential impact and value of a portion of the current portfolio of r&d projects supported by the Office of Industrial Technology and the Forest Products Industry of the Future. The mission of the evaluation was to (a) assess the potential impact of the projects to meet the critical goals of the industry as identified in the vision and roadmapping documents. (b) Evaluate the relationship between the current portfolio of projects and the Agenda 202 Implementation Plan. In addition, evaluate the relationship between the portfolio and the newly revised draft technology strategy being created by the industry. (c) Identify areas where current efforts are making significant progress towards meeting industry goals and identify areas where additional work my be required to meet these goals. (d) Make recommendations to the DOE and the Forest Products Industry on possible improvements in the portfolio and in the current methodology that DOE uses to assess potential impacts on its R&D activities.

  6. Regional Algal Biofuel Production Potential in the Coterminous United States as Affected by Resource Availability Trade-offs

    SciTech Connect

    Venteris, Erik R.; Skaggs, Richard; Wigmosta, Mark S.; Coleman, Andre M.

    2014-03-15

    The warm sunny climate and unoccupied arid lands in the American southwest are favorable factors for algae cultivation. However, additional resources affect the overall viability of specific sites and regions. We investigated the tradeoffs between growth rate, water, and CO2 availability and costs for two strains: N. salina and Chlorella sp. We conducted site selection exercises (~88,000 US sites) to produce 21 billion gallons yr-1 (BGY) of renewable diesel (RD). Experimental trials from the National Alliance for Advanced Biofuels and Bio-Products (NAABB) team informed the growth model of our Biomass Assessment Tool (BAT). We simulated RD production by both lipid extraction and hydrothermal liquefaction. Sites were prioritized by the net value of biofuel minus water and flue gas costs. Water cost models for N. salina were based on seawater and high salinity groundwater and for Chlorella, fresh and brackish groundwater. CO2 costs were based on a flue gas delivery model. Selections constrained by production and water were concentrated along the Gulf of Mexico and southeast Atlantic coasts due to high growth rates and low water costs. Adding flue gas constraints increased the spatial distribution, but the majority of sites remained in the southeast. The 21 BGY target required ~3.8 million hectares of mainly forest (41.3%) and pasture (35.7%). Exclusion in favor of barren and scrub lands forced most production to the southwestern US, but with increased water consumption (5.7 times) and decreased economic efficiency (-38%).

  7. Screening of natural yeast isolates under the effects of stresses associated with second-generation biofuel production.

    PubMed

    Dubey, Rajni; Jakeer, Shaik; Gaur, Naseem A

    2016-05-01

    Robust microorganisms are required for sustainable second-generation biofuel production. We evaluated the growth and fermentation performance of six natural isolates that were derived from grape wine and medicinal herbs using a wide range of carbon sources, rice and wheat straw hydrolysates as well as stress conditions associated with second-generation ethanol production. Sequence analysis of the 5.8S internal transcribed spacer (ITS) and species-specific PCR amplification of the HO gene region assigned the natural isolates to Saccharomyces cerevisiae. Restriction fragment length polymorphism (RFLP) analysis of the mitochondrial DNA revealed that natural yeast isolates are genetically closer to the laboratory strain BY4741 than to the CEN.PK strains. Dextrose fermentation by a natural isolate, MTCC4780, under semi-anaerobic conditions produced maximum ethanol yields of 0.44 g/g and 0.39 g/g, respectively, with and without the stresses encountered during lignocellulosic ethanol fermentation. However, MTCC4780 produced ethanol yields of 0.48 g/g, 0.42 g/g and 0.45 g/g, respectively, with glucose, rice and wheat straw enzymatic hydrolysate fermentation in a bioreactor. The isolates MTCC4781 and MTCC4796 showed higher growth and fermentation performance than did MTCC4780 in the presence of elevated temperature and pre-treatment inhibitors. Taken together, the MTCC4780, MTCC4781 and MTCC4796 strains have the potential to serve as a platform for lignocellulosic ethanol production under stresses associated with second-generation biofuel production. PMID:26481160

  8. Glycogen production for biofuels by the euryhaline cyanobacteria Synechococcus sp. strain PCC 7002 from an oceanic environment

    PubMed Central

    2014-01-01

    Background Oxygenic photosynthetic microorganisms such as cyanobacteria and microalgae have attracted attention as an alternative carbon source for the next generation of biofuels. Glycogen abundantly accumulated in cyanobacteria is a promising feedstock which can be converted to ethanol through saccharification and fermentation processes. In addition, the utilization of marine cyanobacteria as a glycogen producer can eliminate the need for a freshwater supply. Synechococcus sp. strain PCC 7002 is a fast-growing marine coastal euryhaline cyanobacteria, however, the glycogen yield has not yet been determined. In the present study, the effects of light intensity, CO2 concentration, and salinity on the cell growth and glycogen content were investigated in order to maximize glycogen production in Synechococcus sp. strain PCC 7002. Results The optimal culture conditions for glycogen production in Synechococcus sp. strain PCC 7002 were investigated. The maximum glycogen production of 3.5 g L−1 for 7 days (a glycogen productivity of 0.5 g L−1 d−1) was obtained under a high light intensity, a high CO2 level, and a nitrogen-depleted condition in brackish water. The glycogen production performance in Synechococcus sp. strain PCC 7002 was the best ever reported in the α-polyglucan (glycogen or starch) production of cyanobacteria and microalgae. In addition, the robustness of glycogen production in Synechococcus sp. strain PCC 7002 to salinity was evaluated in seawater and freshwater. The peak of glycogen production of Synechococcus sp. strain PCC 7002 in seawater and freshwater were 3.0 and 1.8 g L−1 in 7 days, respectively. Glycogen production in Synechococcus sp. strain PCC 7002 maintained the same level in seawater and half of the level in freshwater compared with the optimal result obtained in brackish water. Conclusions We conclude that Synechococcus sp. strain PCC 7002 has high glycogen production activity and glycogen can be provided from coastal water accompanied by a fluctuation of salinity. This work supports Synechococcus sp. strain PCC 7002 as a promising carbohydrate source for biofuel production. PMID:24959200

  9. Transporter-mediated biofuel secretion.

    PubMed

    Doshi, Rupak; Nguyen, Tuan; Chang, Geoffrey

    2013-05-01

    Engineering microorganisms to produce biofuels is currently among the most promising strategies in renewable energy. However, harvesting these organisms for extracting biofuels is energy- and cost-intensive, limiting the commercial feasibility of large-scale production. Here, we demonstrate the use of a class of transport proteins of pharmacological interest to circumvent the need to harvest biomass during biofuel production. We show that membrane-embedded transporters, better known to efflux lipids and drugs, can be used to mediate the secretion of intracellularly synthesized model isoprenoid biofuel compounds to the extracellular milieu. Transporter-mediated biofuel secretion sustainably maintained an approximate three- to fivefold boost in biofuel production in our Escherichia coli test system. Because the transporters used in this study belong to the ubiquitous ATP-binding cassette protein family, we propose their use as "plug-and-play" biofuel-secreting systems in a variety of bacteria, cyanobacteria, diatoms, yeast, and algae used for biofuel production. This investigation showcases the potential of expressing desired membrane transport proteins in cell factories to achieve the export or import of substances of economic, environmental, or therapeutic importance. PMID:23613592

  10. Transporter-mediated biofuel secretion

    PubMed Central

    Doshi, Rupak; Nguyen, Tuan; Chang, Geoffrey

    2013-01-01

    Engineering microorganisms to produce biofuels is currently among the most promising strategies in renewable energy. However, harvesting these organisms for extracting biofuels is energy- and cost-intensive, limiting the commercial feasibility of large-scale production. Here, we demonstrate the use of a class of transport proteins of pharmacological interest to circumvent the need to harvest biomass during biofuel production. We show that membrane-embedded transporters, better known to efflux lipids and drugs, can be used to mediate the secretion of intracellularly synthesized model isoprenoid biofuel compounds to the extracellular milieu. Transporter-mediated biofuel secretion sustainably maintained an approximate three- to fivefold boost in biofuel production in our Escherichia coli test system. Because the transporters used in this study belong to the ubiquitous ATP-binding cassette protein family, we propose their use as “plug-and-play” biofuel-secreting systems in a variety of bacteria, cyanobacteria, diatoms, yeast, and algae used for biofuel production. This investigation showcases the potential of expressing desired membrane transport proteins in cell factories to achieve the export or import of substances of economic, environmental, or therapeutic importance. PMID:23613592

  11. Method development for the characterization of biofuel intermediate products using gas chromatography with simultaneous mass spectrometric and flame ionization detections.

    PubMed

    Sťávová, Jana; Stahl, Danese C; Seames, Wayne S; Kubátová, Alena

    2012-02-10

    Accurate analytical methods are required to develop and evaluate the quality of new renewable transportation fuels and intermediate organic liquid products (OLPs). Unfortunately, existing methods developed for the detailed characterization of petroleum products, are not accurate for many of the OLPs generated from non-petroleum feedstocks. In this study, a method was developed and applied to the detailed characterization of complex OLPs formed during triacylglyceride (TG) pyrolysis which is the basis for generating one class of emerging biofuels. This method uses gas chromatography coupled simultaneously with flame ionization and mass spectrometry detectors (GC-FID/MS). The FID provided accurate quantification of carbonaceous species while MS enabled identification of unknown compounds. A programed temperature vaporizer using a 25 °C, 0.1 min, 720 °C min(-1), 350 °C, 5 min temperature program is employed which minimizes compound discrimination better than the more commonly utilized split/splitless injector, as verified with injections at 250 and 350 °C. Two standard mixtures featuring over 150 components are used for accurate identification and a designed calibration standard accounts for compound discrimination at the injector and differing FID responses of various classes of compounds. This new method was used to identify and quantify over 250 species in OLPs generated from canola oil, soybean oil, and canola methyl ester (CME). In addition to hydrocarbons, the method was used to quantify polar (upon derivatization) and unidentified species, plus the unresolved complex mixture that has not typically been determined in previous studies. Repeatability of the analytical method was below 5% RSD for all individual components. Using this method, the mass balance was closed for samples derived from canola and soybean oil but only ca. 77 wt% of the OLP generated from CME could be characterized. The ability to close the mass balance depended on sample origin, demonstrating the need for an accurate quantification method for biofuels at various stages of production. PMID:22245174

  12. Research Summary: Corrosion Considerations for Thermochemical Biomass Liquefaction Process Systems in Biofuel Production

    SciTech Connect

    Brady, Michael P; Keiser, James R; Leonard, Donovan N; Whitmer, Lysle; Thomson, Jeffery K

    2014-01-01

    Thermochemical liquifaction processing of biomass to produce bio-derived fuels (e.g. gasoline, jet fuel, diesel, home heating oil, etc.) is of great recent interest as a renewable energy source. Approaches under investigation include direct liquefaction, hydrothermal liquefaction, hydropyrolysis, fast pyrolysis, etc. to produce energy dense liquids that can be utilized as produced or further processed to provide products of higher value. An issue with bio-oils is that they tend to contain significant concentrations of organic compounds, which make the bio-oil acidic and a potential source of corrosion issues in in transport, storage, and use. Efforts devoted to modified/further processing of bio-oils to make them less corrosive are currently being widely pursued. Another aspect that must also be addressed is potential corrosion issues in the bio-oil liquefaction process equipment itself. Depending on the specific process, bio-oil liquefaction production temperatures can reach up to 400-600 C, and involve the presence of aggressive sulfur, and halide species from both the biomass used and/or process additives. Detailed knowledge of the corrosion resistance of candidate process equipment alloys in these bio-oil production environments is currently lacking. This paper summarizes our recent, ongoing efforts to assess the extent to which corrosion of bio-oil process equipment may be an issue, with the ultimate goal of providing the basis to select the lowest cost alloy grades capable of providing the long-term corrosion resistance needed for future bio-oil production plants.

  13. Corrosion Considerations for Thermochemical Biomass Liquefaction Process Systems in Biofuel Production

    NASA Astrophysics Data System (ADS)

    Brady, M. P.; Keiser, J. R.; Leonard, D. N.; Whitmer, L.; Thomson, J. K.

    2014-12-01

    Thermochemical liquefaction processing of biomass to produce bio-derived fuels (e.g., gasoline, jet fuel, diesel, home heating oil, etc.) is of great recent interest as a renewable energy source. Approaches under investigation include direct liquefaction, hydrothermal liquefaction, hydropyrolysis, fast pyrolysis, etc., to produce energy dense liquids that can be utilized as produced or further processed to provide products of higher value. An issue with bio-oils is that they tend to contain significant concentrations of organic oxygenates, including acids, which make the bio-oil a potential source of corrosion issues in transport, storage, and use. Efforts devoted to modified/further processing of bio-oils to make them less corrosive are currently being widely pursued. Another issue that must also be addressed in bio-oil liquefaction is potential corrosion issues in the process equipment. Depending on the specific process, bio-oil liquefaction production temperatures are typically in the 300-600°C range, and the process environment can contain aggressive sulfur and halide species from both the biomass used and/or process additives. Detailed knowledge of the corrosion resistance of candidate process equipment alloys in these bio-oil production environments is currently lacking. This paper summarizes recent, ongoing efforts to assess the extent of corrosion of bio-oil process equipment, with the ultimate goal of providing a basis for the selection of the lowest cost alloy grades capable of providing the long-term corrosion resistance needed for future bio-oil production plants.

  14. Research Summary: Corrosion Considerations for Thermochemical Biomass Liquefaction Process Systems in Biofuel Production

    DOE PAGESBeta

    Brady, Michael P; Keiser, James R; Leonard, Donovan N; Whitmer, Lysle; Thomson, Jeffery K

    2014-01-01

    Thermochemical liquifaction processing of biomass to produce bio-derived fuels (e.g. gasoline, jet fuel, diesel, home heating oil, etc.) is of great recent interest as a renewable energy source. Approaches under investigation include direct liquefaction, hydrothermal liquefaction, hydropyrolysis, fast pyrolysis, etc. to produce energy dense liquids that can be utilized as produced or further processed to provide products of higher value. An issue with bio-oils is that they tend to contain significant concentrations of organic compounds, which make the bio-oil acidic and a potential source of corrosion issues in in transport, storage, and use. Efforts devoted to modified/further processing of bio-oilsmore » to make them less corrosive are currently being widely pursued. Another aspect that must also be addressed is potential corrosion issues in the bio-oil liquefaction process equipment itself. Depending on the specific process, bio-oil liquefaction production temperatures can reach up to 400-600 C, and involve the presence of aggressive sulfur, and halide species from both the biomass used and/or process additives. Detailed knowledge of the corrosion resistance of candidate process equipment alloys in these bio-oil production environments is currently lacking. This paper summarizes our recent, ongoing efforts to assess the extent to which corrosion of bio-oil process equipment may be an issue, with the ultimate goal of providing the basis to select the lowest cost alloy grades capable of providing the long-term corrosion resistance needed for future bio-oil production plants.« less

  15. Overview on Biofuels from a European Perspective

    ERIC Educational Resources Information Center

    Ponti, Luigi; Gutierrez, Andrew Paul

    2009-01-01

    In light of the recently developed European Union (EU) Biofuels Strategy, the literature is reviewed to examine (a) the coherency of biofuel production with the EU nonindustrial vision of agriculture, and (b) given its insufficient land base, the implications of a proposed bioenergy pact to grow biofuel crops in the developing world to meet EU

  16. Overview on Biofuels from a European Perspective

    ERIC Educational Resources Information Center

    Ponti, Luigi; Gutierrez, Andrew Paul

    2009-01-01

    In light of the recently developed European Union (EU) Biofuels Strategy, the literature is reviewed to examine (a) the coherency of biofuel production with the EU nonindustrial vision of agriculture, and (b) given its insufficient land base, the implications of a proposed bioenergy pact to grow biofuel crops in the developing world to meet EU…

  17. Assessing the environmental sustainability of biofuels.

    PubMed

    Kazamia, Elena; Smith, Alison G

    2014-10-01

    Biofuels vary in their potential to reduce greenhouse gas emissions when displacing fossil fuels. Savings depend primarily on the crop used for biofuel production, and on the effect that expanding its cultivation has on land use. Evidence-based policies should be used to ensure that maximal sustainability benefits result from the development of biofuels. PMID:25281367

  18. The potential of freshwater macroalgae as a biofuels feedstock and the influence of nutrient availability on freshwater macroalgal biomass production

    NASA Astrophysics Data System (ADS)

    Yun, Jin-Ho

    Extensive efforts have been made to evaluate the potential of microalgae as a biofuel feedstock during the past 4-5 decades. However, filamentous freshwater macroalgae have numerous characteristics that favor their potential use as an alternative algal feedstock for biofuels production. Freshwater macroalgae exhibit high rates of areal productivity, and their tendency to form dense floating mats on the water surface imply significant reductions in harvesting and dewater costs compared to microalgae. In Chapter 1, I reviewed the published literature on the elemental composition and energy content of five genera of freshwater macroalgae. This review suggested that freshwater macroalgae compare favorably with traditional bio-based energy sources, including terrestrial residues, wood, and coal. In addition, I performed a semi-continuous culture experiment using the common Chlorophyte genus Oedogonium to investigate whether nutrient availability can influence its higher heating value (HHV), productivity, and proximate analysis. The experimental study suggested that the most nutrient-limited growth conditions resulted in a significant increase in the HHV of the Oedogonium biomass (14.4 MJ/kg to 16.1 MJ/kg). Although there was no significant difference in productivity between the treatments, the average dry weight productivity of Oedogonium (3.37 g/m2/day) was found to be much higher than is achievable with common terrestrial plant crops. Although filamentous freshwater macroalgae, therefore, have significant potential as a renewable source of bioenergy, the ultimate success of freshwater macroalgae as a biofuel feedstock will depend upon the ability to produce biomass at the commercial-scale in a cost-effective and sustainable manner. Aquatic ecology can play an important role to achieve the scale-up of algal crop production by informing the supply rates of nutrients to the cultivation systems, and by helping to create adaptive production systems that are resilient to environmental change. In Chapter 2, I performed a review and an analysis of data from the published literature on the large-cultivation of freshwater macroalgae. This study revealed that the large-scale cultivation of freshwater macroalgae is feasible at relatively low cost using currently available technologies such as the Algal Turf Scrubber system (ATS). In addition, graphical analyses of published data obtained from ATS systems of varying sizes in operation worldwide revealed that both macroalgal biomass productivity and nutrient removal rates are hyperbolically related to the areal loading rates of both total nitrogen and total phosphorus. An assessment of the limited existing literature on carbon dioxide amendments suggested that the effectiveness and need for CO2 supplementation of macroalgal production systems like the ATS has not yet been conclusively demonstrated. Overall, this thesis demonstrates that filamentous freshwater macroalgae have great potential as a feedstock for both liquid and solid fuels, especially if nutrient-rich wastewater can be used as the supply of water and mineral nutrients. In addition, this thesis highlights the importance of studying the algal cultivation conditions that influence trade-offs between nutrient loading, biomass productivity, and biomass energy content. In particular, the hyperbolic relationship between algal biomass productivity and the areal loading rates of both total nitrogen and total phosphorus should provide critical insight when considering the production costs of macroalgal biomass at the commercial-scale.

  19. World Biofuels Study

    SciTech Connect

    Alfstad,T.

    2008-10-01

    This report forms part of a project entitled 'World Biofuels Study'. The objective is to study world biofuel markets and to examine the possible contribution that biofuel imports could make to help meet the Renewable Fuel Standard (RFS) of the Energy Independence and Security Act of 2007 (EISA). The study was sponsored by the Biomass Program of the Assistant Secretary for Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy. It is a collaborative effort among the Office of Policy and International Affairs (PI), Department of Energy and Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL) and Brookhaven National Laboratory (BNL). The project consisted of three main components: (1) Assessment of the resource potential for biofuel feedstocks such as sugarcane, grains, soybean, palm oil and lignocellulosic crops and development of supply curves (ORNL). (2) Assessment of the cost and performance of biofuel production technologies (NREL). (3) Scenario-based analysis of world biofuel markets using the ETP global energy model with data developed in the first parts of the study (BNL). This report covers the modeling and analysis part of the project conducted by BNL in cooperation with PI. The Energy Technology Perspectives (ETP) energy system model was used as the analytical tool for this study. ETP is a 15 region global model designed using the MARKAL framework. MARKAL-based models are partial equilibrium models that incorporate a description of the physical energy system and provide a bottom-up approach to study the entire energy system. ETP was updated for this study with biomass resource data and biofuel production technology cost and performance data developed by ORNL and NREL under Tasks 1 and 2 of this project. Many countries around the world are embarking on ambitious biofuel policies through renewable fuel standards and economic incentives. As a result, the global biofuel demand is expected to grow very rapidly over the next two decades, provided policymakers stay the course with their policy goals. This project relied on a scenario-based analysis to study global biofuel markets. Scenarios were designed to evaluate the impact of different policy proposals and market conditions. World biofuel supply for selected scenarios is shown in Figure 1. The reference case total biofuel production increases from 12 billion gallons of ethanol equivalent in 2005 to 54 billion gallons in 2020 and 83 billion gallons in 2030. The scenarios analyzed show volumes ranging from 46 to 64 billion gallons in 2020, and from about 72 to about 100 billion gallons in 2030. The highest production worldwide occurs in the scenario with high feedstock availability combined with high oil prices and more rapid improvements in cellulosic biofuel conversion technologies. The lowest global production is found in the scenario with low feedstock availability, low oil prices and slower technology progress.

  20. Integrated automation for continuous high-throughput synthetic chromosome assembly and transformation to identify improved yeast strains for industrial production of biofuels and bio-based chemicals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An exponential increase in our understanding of genomes, proteomes, and metabolomes provides greater impetus to address critical biotechnological issues such as sustainable production of biofuels and bio-based chemicals and, in particular, the development of improved microbial biocatalysts for use i...

  1. Use of biofuel by-product from the green algae Desmochloris sp. and diatom Nanofrustulum sp. meal in diets for nile tilapia Oreochromis niloticus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Algal by-product meals from the Hawaiian biofuels industry were evaluated as protein ingredients in diets for juveniles of Nile tilapia (Oreochromis niloticus). Four experimental diets were formulated to contain 40% protein and were made with fish meal, soybean meal, whole diatom (Nanofrustulum sp.)...

  2. Development of synthetic chromosomes and improved microbial strains to utilize cellulosic feedstocks and express valuable coproducts for sustainable production of biofuels from corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A sustainable biorefinery must convert a broad range of renewable feedstocks into a variety of product streams, including fuels, power, and value-added bioproducts. To accomplish this, microbial-based technologies that enable new commercially viable coproducts from corn-to-ethanol biofuel fermentati...

  3. Combinatorial Design of a Highly Efficient Xylose-Utilizing Pathway in Saccharomyces cerevisiae for the Production of Cellulosic Biofuels

    PubMed Central

    Kim, Byoungjin; Du, Jing; Eriksen, Dawn T.

    2013-01-01

    Balancing the flux of a heterologous metabolic pathway by tuning the expression and properties of the pathway enzymes is difficult, but it is critical to realizing the full potential of microbial biotechnology. One prominent example is the metabolic engineering of a Saccharomyces cerevisiae strain harboring a heterologous xylose-utilizing pathway for cellulosic-biofuel production, which remains a challenge even after decades of research. Here, we developed a combinatorial pathway-engineering approach to rapidly create a highly efficient xylose-utilizing pathway for ethanol production by exploring various combinations of enzyme homologues with different properties. A library of more than 8,000 xylose utilization pathways was generated using DNA assembler, followed by multitiered screening, which led to the identification of a number of strain-specific combinations of the enzymes for efficient conversion of xylose to ethanol. The balancing of metabolic flux through the xylose utilization pathway was demonstrated by a complete reversal of the major product from xylitol to ethanol with a similar yield and total by-product formation as low as 0.06 g/g xylose without compromising cell growth. The results also suggested that an optimal enzyme combination depends on not only the genotype/phenotype of the host strain, but also the sugar composition of the fermentation medium. This combinatorial approach should be applicable to any heterologous pathway and will be instrumental in the optimization of industrial production of value-added products. PMID:23183982

  4. Fueling the Future with Fungal Genomics

    SciTech Connect

    Grigoriev, Igor V.; Cullen, Daniel; Hibbett, David; Goodwin, Stephen B.; Jeffries, Thomas W.; Kubicek, Christian P.; Kuske, Cheryl; Magnuson, Jon K.; Martin, Francis; Spatafora, Joey; Tsang, Adrian; Baker, Scott E.

    2011-04-29

    Fungi play important roles across the range of current and future biofuel production processes. From crop/feedstock health to plant biomass saccharification, enzyme production to bioprocesses for producing ethanol, higher alcohols or future hydrocarbon biofuels, fungi are involved. Research and development are underway to understand the underlying biological processes and improve them to make bioenergy production efficient on an industrial scale. Genomics is the foundation of the systems biology approach that is being used to accelerate the research and development efforts across the spectrum of topic areas that impact biofuels production. In this review, we discuss past, current and future advances made possible by genomic analyses of the fungi that impact plant/feedstock health, degradation of lignocellulosic biomass and fermentation of sugars to ethanol, hydrocarbon biofuels and renewable chemicals.

  5. Biological nitrogen fixation in sugar cane: A key to energetically viable biofuel production

    SciTech Connect

    Boddey, R.M.

    1995-05-01

    The advantages of producing biofuels to replace fossil energy sources are derived from the fact that the energy accumulated in the biomass in captured directly from photosynthesis and is thus renewable, and that the cycle of carbon dioxide fixation by the crop, followed by burning of the fuel makes no overall contribution to atmospheric CO{sub 2} or, consequently, to global warming. However, these advantages are negated if large quantities of fossil fuels need to be used to grow or process the biofuel crop. In this regard, the Brazilian bioethanol program, based on the fermentation/distillation of sugar cane juice, is particularly favorable, not only because the crop is principally hand harvested, but also because of the low nitrogen fertilizer use on sugar cane in Brazil. Recent {sup 15}N and N balance studies have shown that in some Brazilian cane varieties, high yields are possible without N fertilization because the plants are able to obtain large contributions of nitrogen from plant-associated biological N{sub 2} fixation (BNF). The N{sub 2}-fixing acid-tolerant bacterium Acetobacter diazotrophicus was first found to occur within roots, stems, and leaves of sugar cane. Subsequently, two species of Herbaspirillum also have been found to occur within the interior of all sugar cane tissues. The discovery of these, and other N{sub 2}-fixing bacteria that survive poorly in soil but thrive within plant tissue (endophytic bacteria), may account for the high BNF contributions observed in sugar cane. Further study of this system should allow the gradual elimination of N fertilizer use on sugar cane, at least in Brazil, and opens up the possibility of the extension of this efficient N{sub 2}-fixing system to cereal and other crops with consequent immense potential benefits to tropical agriculture. 44 refs., 9 figs., 4 tabs.

  6. Assessing the quality of a deliberative democracy mini-public event about advanced biofuel production and development in Canada.

    PubMed

    Longstaff, Holly; Secko, David M

    2016-02-01

    The importance of evaluating deliberative public engagement events is well recognized, but such activities are rarely conducted for a variety of theoretical, political and practical reasons. In this article, we provide an assessment of the criteria presented in the 2008 National Research Council report on Public Participation in Environmental Assessment and Decision Making (NRC report) as explicit indicators of quality for the 2012 'Advanced Biofuels' deliberative democracy event. The National Research Council's criteria were selected to evaluate this event because they are decision oriented, are the products of an exhaustive review of similar past events, are intended specifically for environmental processes and encompass many of the criteria presented in other evaluation frameworks. It is our hope that the results of our study may encourage others to employ and assess the National Research Council's criteria as a generalizable benchmark that may justifiably be used in forthcoming deliberative events exploring different topics with different audiences. PMID:25164558

  7. Potential impacts of intensive cellulosic biofuel production on water quality and quantity in the Upper Coast Plain, US

    NASA Astrophysics Data System (ADS)

    Vache, K. B.; Jackson, C. R.; Bitew, M. M.; Blake, J.; McDonnell, J. J.; Griffiths, N.

    2013-12-01

    This study outlines a long-term project focused on impacts of short-rotation loblolly pine production as a biofuel feedstock. The project was initiated in 2009 and focused on the development of a baseline dataset developed from hydrometric, isotopic, and water quality monitoring of a set of small paired catchments. In the winter of 2013 a series of treatments, representing typical forest management strategies in the southeastern US were implemented, and monitoring will continue through 2018. The detailed monitoring program has resulted in a conceptual model of catchment hydrological function, which is being used to scale the observational evidence up to larger watershed scales. The presentation focuses primarily on these modeling results, with particular emphasis on the influence of short rotation harvest on groundwater recharge and stream water quantity over decadal scales.

  8. 17 CFR 41.41 - Security futures products accounts.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 2 2014-04-01 2014-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION (CONTINUED) SECURITY FUTURES PRODUCTS Customer Accounts and Margin Requirements § 41.41 Security...

  9. National Algal Biofuels Technology Roadmap

    SciTech Connect

    Ferrell, John; Sarisky-Reed, Valerie

    2010-05-01

    The framework for National Algal Biofuels Technology Roadmap was constructed at the Algal Biofuels Technology Roadmap Workshop, held December 9-10, 2008, at the University of Maryland-College Park. The Workshop was organized by the Biomass Program to discuss and identify the critical challenges currently hindering the development of a domestic, commercial-scale algal biofuels industry. This Roadmap presents information from a scientific, economic, and policy perspectives that can support and guide RD&D investment in algal biofuels. While addressing the potential economic and environmental benefits of using algal biomass for the production of liquid transportation fuels, the Roadmap describes the current status of algae RD&D. In doing so, it lays the groundwork for identifying challenges that likely need to be overcome for algal biomass to be used in the production of economically viable biofuels.

  10. International Trade of Biofuels (Brochure)

    SciTech Connect

    Not Available

    2013-05-01

    In recent years, the production and trade of biofuels has increased to meet global demand for renewable fuels. Ethanol and biodiesel contribute much of this trade because they are the most established biofuels. Their growth has been aided through a variety of policies, especially in the European Union, Brazil, and the United States, but ethanol trade and production have faced more targeted policies and tariffs than biodiesel. This fact sheet contains a summary of the trade of biofuels among nations, including historical data on production, consumption, and trade.

  11. The Role of Social Constructions and Biophysical Attributes of the Environment in Decision-Making in the Context of Biofuels and Rubber Production Partnership Regimes in Upland Philippines

    NASA Astrophysics Data System (ADS)

    Montefrio, M. F.

    2012-12-01

    Burgeoning attention in biofuels and natural rubber has spurred interest among governments and private companies in integrating marginalized communities into global commodity markets. Upland farmers from diverse cultural backgrounds and biophysical settings today are deciding whether to agree with partnership proposals from governments and private firms to grow biofuels and natural rubber. In this paper, I examine whether upland farmers' socio-environmental constructions (evaluative beliefs, place satisfaction, and ecological worldviews) and the actual biophysical attributes (land cover and soil types) of upland environments, respectively, function as significant predictors of the intent and decisions of indigenous and non-indigenous farmers to cooperate with government and private actors to establish certain biofuel crops and natural rubber production systems in Palawan, Philippines. Drawing from ethnography and statistical analysis of household surveys, I propose that social constructions and the biophysical attributes of the environment are closely related with each other and in turn both influence individual decision-making behavior in resource-based production partnership regimes. This has significant implications on the resilience of socio-ecological systems, particularly agro-ecosystems, as certain upland farmers prefer to engage in intensive, monocrop production of biofuels and natural rubber on relatively more biodiverse areas, such as secondary forests and traditional shifting cultivation lands. The study aims to advance new institutional theories of resource management, particularly Ostrom's Institutional Analysis and Development and Socio-Ecological Systems frameworks, and scholarship on environmental decision-making in the context of collective action.

  12. Assessment of the Projected One Billion Ton Biomass for Cellulosic Biofuel Production and Its Potential Implications on Regional Water Quality and Availability

    NASA Astrophysics Data System (ADS)

    Demissie, Y. K.; Yan, E.; Wu, M.

    2011-12-01

    The DOE and USDA joint study, also commonly referred as the "Billion-Ton" study, assessed the cellulosic feedstock resources potential in the U.S. for producing second generation biofuel to replace 30 percent of the country's transportation fuels by year 2030. The available resource is expected to come from changing cropping pattern, increasing crop yield, harvesting agricultural and forest wood residues, and developing energy crops. Such large-scale changes in land use and crop managements are likely to affect the associated water quality and resources at both regional and local scales. To address the water sustainability associated with the projected biomass production in the Upper Mississippi River Basin (UMRB), we have developed a SWAT watershed model that simulate the changes in water quality (nitrogen, phosphorus, and soil erosion) and resources (soil water content, evapotranspiration, and runoff) of the region due to future biomass production scenario estimated by the Billion-Ton study. The scenario is implemented by changing the model inputs and parameters at subbasin and hydrologic response unit levels, as well as by improving the SWAT model to represent spatially varying crop properties. The potential impacts on water quality and water availability were compared with the results obtained from a baseline simulation which represents current watershed conditions and existing level of feedstock production. The basin level results suggested mixed effects on the water quality. The projected large-scale biomass production scenario is expected to decrease loadings of total nitrogen and nitrate in the streams while increase total phosphorus and suspended sediment. Results indicate an increase in the rate of evapotranspiration and a decrease in the soil water content and in surface runoff. discharge to the streams. The impacts at the subbasin or local scale varies spatially and temporally depending on the types of land use change, their locations, and crop managements, suggesting needs to further optimize the sustainable biomass production from water resource perspective at both regional and local levels.

  13. Shifting lands: exploring Kansas farmer decision-making in an era of climate change and biofuels production.

    PubMed

    White, Stacey Swearingen; Selfa, Theresa

    2013-02-01

    While farming has been the subject of frequent critical analysis with respect to its environmental impacts, including its greenhouse gas emissions, there has been relatively little consideration of the potentially positive role of agriculture in responding to a future greatly influenced by climate change. One possible realm for agriculture to contribute successfully to this future is through biofuels cultivation. This paper uses the state of Kansas as an example to examine factors that are influencing farmer decision-making during a time of heightened debates about climate and energy. Drawing on interviews with key informants and Kansas farmers, we apply and refine a conceptual model for understanding farmer decisions. We find that farmers have largely positive perceptions of the natural environment. Climate change, especially, is not a salient concern at this time. Factors that appear most likely to influence farmer decisions to adopt a new practice include the relative advantage of that practice and the ability to learn about and discuss it through existing social networks. Successful policy incentives must provide farmers with a continued sense of both independence and contribution to greater societal good. PMID:23229828

  14. Shifting Lands: Exploring Kansas Farmer Decision-Making in an Era of Climate Change and Biofuels Production

    NASA Astrophysics Data System (ADS)

    White, Stacey Swearingen; Selfa, Theresa

    2013-02-01

    While farming has been the subject of frequent critical analysis with respect to its environmental impacts, including its greenhouse gas emissions, there has been relatively little consideration of the potentially positive role of agriculture in responding to a future greatly influenced by climate change. One possible realm for agriculture to contribute successfully to this future is through biofuels cultivation. This paper uses the state of Kansas as an example to examine factors that are influencing farmer decision-making during a time of heightened debates about climate and energy. Drawing on interviews with key informants and Kansas farmers, we apply and refine a conceptual model for understanding farmer decisions. We find that farmers have largely positive perceptions of the natural environment. Climate change, especially, is not a salient concern at this time. Factors that appear most likely to influence farmer decisions to adopt a new practice include the relative advantage of that practice and the ability to learn about and discuss it through existing social networks. Successful policy incentives must provide farmers with a continued sense of both independence and contribution to greater societal good.

  15. Water use implications of biofuel scenarios

    NASA Astrophysics Data System (ADS)

    Teter, J.; Mishra, G. S.; Yeh, S.

    2012-12-01

    Existing studies rely upon attributional lifecycle analysis (LCA) approaches to estimate water intensity of biofuels in liters of irrigated/evapotranspiration water consumed for biofuel production. Such approaches can be misleading. From a policy perspective, a better approach is to compare differential water impacts among scenarios on a landscape scale. We address the shortcomings of existing studies by using consequential LCA, and incorporate direct and indirect land use (changes) of biofuel scenarios, marginal vs. average biofuel water use estimates, future climate, and geographic heterogeneity. We use the outputs of a partial equilibrium economic model, climate and soil data, and a process-based crop-soil-climate-water model to estimate differences in green water (GW - directly from precipitation to soil) and blue water (BW - supplied by irrigation) use among three scenarios: (1) business-as-usual (BAU), (2) Renewable Fuels Standard (RFS) mandates, and (3) a national Low Carbon Fuel Standard (LCFS) plus the RFS scenario. We use spatial statistical methods to interpolate key climatic variables using daily climate observations for the contiguous USA. Finally, we use FAO's crop model AquaCrop to estimate the domestic GW and BW impacts of biofuel policies from 2007-2035. We assess the differences among scenarios along the following metrics: (1) crop area expansion at the county level, including prime and marginal lands, (2) crop-specific and overall annual/seasonal water balances including (a) water inflows (irrigation & precipitation), (b) crop-atmosphere interactions: (evaporation & transpiration) and (d) soil-water flows (runoff & soil infiltration), in mm 3 /acre over the relevant time period. The functional unit of analysis is the BW and GW requirements of biofuels (mm3 per Btu biofuel) at the county level. Differential water use impacts among scenarios are a primarily a function of (1) land use conversion, in particular that of formerly uncropped land classes (2) irrigation practices, (3) feedstock water use efficiency, and (4) the longer growing season and a predominance of rainfed cultivation of dedicated biofuel feedstocks. National-level total water use is lowest in the BAU scenario and highest in the RFS2 + LCFS scenario. Figure: Million acres converted to growing miscanthus (top) & switchgrass (bottom) under the RFS + LCFS scenario in 2035. Land use classes are crop pasture (blue), idle cropland (red-purple) & prime cropland (brown).

  16. Feedstock handling and processing effects on biochemical conversion to biofuels

    SciTech Connect

    Daniel Inman; Nick Nagle; Jacob Jacobson; Erin Searcy; Allison Ray

    2001-10-01

    Abating the dependence of the United States on foreign oil by reducing oil consumption and increasing biofuels usage will have far-reaching global effects. These include reduced greenhouse gas emissions and an increased demand for biofuel feedstocks. To support this increased demand, cellulosic feedstock production and conversion to biofuels (e.g. ethanol, butanol) is being aggressively researched. Thus far, research has primarily focused on optimizing feedstock production and ethanol conversion, with less attention given to the feedstock supply chain required to meet cost, quality, and quantity goals. This supply chain comprises a series of unit operations from feedstock harvest to feeding the conversion process. Our objectives in this review are (i) to summarize the peer-reviewed literature on harvest-to-reactor throat variables affecting feedstock composition and conversion to ethanol; (ii) to identify knowledge gaps; and (iii) to recommend future steps.

  17. Microbial surface displayed enzymes based biofuel cell utilizing degradation products of lignocellulosic biomass for direct electrical energy.

    PubMed

    Fan, Shuqin; Hou, Chuantao; Liang, Bo; Feng, Ruirui; Liu, Aihua

    2015-09-01

    In this work, a bacterial surface displaying enzyme based two-compartment biofuel cell for the direct electrical energy conversion from degradation products of lignocellulosic biomass is reported. Considering that the main degradation products of the lignocellulose are glucose and xylose, xylose dehydrogenase (XDH) displayed bacteria (XDH-bacteria) and glucose dehydrogenase (GDH) displayed bacteria (GDH-bacteria) were used as anode catalysts in anode chamber with methylene blue as electron transfer mediator. While the cathode chamber was constructed with laccase/multi-walled-carbon nanotube/glassy-carbon-electrode. XDH-bacteria exhibited 1.75 times higher catalytic efficiency than GDH-bacteria. This assembled enzymatic fuel cell exhibited a high open-circuit potential of 0.80 V, acceptable stability and energy conversion efficiency. Moreover, the maximum power density of the cell could reach 53 μW cm(-2) when fueled with degradation products of corn stalk. Thus, this finding holds great potential to directly convert degradation products of biomass into electrical energy. PMID:26051524

  18. Fueling the future with fungal genomics

    SciTech Connect

    Grigoriev, Igor V.; Cullen, Dan; Goodwin, Steve X.; Hibbett, David; Jeffries, Thomas W.; Kubicek, Christian P.; Kuske, Cheryl R.; Magnuson, Jon K.; Martin, Francis; Spatafora, Joe W.; Tsang, Adrian; Baker, Scott E.

    2011-07-25

    Fungi play important roles across the range of current and future biofuel production processes. From crop/feedstock health to plant biomass saccharification, enzyme production to bioprocesses for producing ethanol, higher alcohols or future hydrocarbon biofuels, fungi are involved. Research and development are underway to understand the underlying biological processes and improve them to make efficient on an industrial scale. Genomics is the foundation of the systems biology approach that is being used to accelerate the research and development efforts across the spectrum of topic areas that impact biofuels production. In this review, we discuss past, current and future advances made possible by genomic analysis of the fungi that impact plant/feedstock health, degradation of lignocellulosic biomass and fermentation of sugars to ethanol, hydrocarbon biofuels and renewable chemicals.

  19. Beetles, Biofuel, and Coffee

    SciTech Connect

    Ceja-Navarro, Javier

    2015-05-06

    Berkeley Lab scientist Javier Ceja-Navarro discusses his research on the microbial populations found the guts of insects, specifically the coffee berry borer, which may lead to better pest management and the passalid beetle, which could lead to improved biofuel production.

  20. Biofuel impacts on water.

    SciTech Connect

    Tidwell, Vincent Carroll; Malczynski, Leonard A.; Sun, Amy Cha-Tien

    2011-01-01

    Sandia National Laboratories and General Motors Global Energy Systems team conducted a joint biofuels systems analysis project from March to November 2008. The purpose of this study was to assess the feasibility, implications, limitations, and enablers of large-scale production of biofuels. 90 billion gallons of ethanol (the energy equivalent of approximately 60 billion gallons of gasoline) per year by 2030 was chosen as the book-end target to understand an aggressive deployment. Since previous studies have addressed the potential of biomass but not the supply chain rollout needed to achieve large production targets, the focus of this study was on a comprehensive systems understanding the evolution of the full supply chain and key interdependencies over time. The supply chain components examined in this study included agricultural land use changes, production of biomass feedstocks, storage and transportation of these feedstocks, construction of conversion plants, conversion of feedstocks to ethanol at these plants, transportation of ethanol and blending with gasoline, and distribution to retail outlets. To support this analysis, we developed a 'Seed to Station' system dynamics model (Biofuels Deployment Model - BDM) to explore the feasibility of meeting specified ethanol production targets. The focus of this report is water and its linkage to broad scale biofuel deployment.

  1. Engineered Respiro-Fermentative Metabolism for the Production of Biofuels and Biochemicals from Fatty Acid-Rich Feedstocks▿ †

    PubMed Central

    Dellomonaco, Clementina; Rivera, Carlos; Campbell, Paul; Gonzalez, Ramon

    2010-01-01

    Although lignocellulosic sugars have been proposed as the primary feedstock for the biological production of renewable fuels and chemicals, the availability of fatty acid (FA)-rich feedstocks and recent progress in the development of oil-accumulating organisms make FAs an attractive alternative. In addition to their abundance, the metabolism of FAs is very efficient and could support product yields significantly higher than those obtained from lignocellulosic sugars. However, FAs are metabolized only under respiratory conditions, a metabolic mode that does not support the synthesis of fermentation products. In the work reported here we engineered several native and heterologous fermentative pathways to function in Escherichia coli under aerobic conditions, thus creating a respiro-fermentative metabolic mode that enables the efficient synthesis of fuels and chemicals from FAs. Representative biofuels (ethanol and butanol) and biochemicals (acetate, acetone, isopropanol, succinate, and propionate) were chosen as target products to illustrate the feasibility of the proposed platform. The yields of ethanol, acetate, and acetone in the engineered strains exceeded those reported in the literature for their production from sugars, and in the cases of ethanol and acetate they also surpassed the maximum theoretical values that can be achieved from lignocellulosic sugars. Butanol was produced at yields and titers that were between 2- and 3-fold higher than those reported for its production from sugars in previously engineered microorganisms. Moreover, our work demonstrates production of propionate, a compound previously thought to be synthesized only by propionibacteria, in E. coli. Finally, the synthesis of isopropanol and succinate was also demonstrated. The work reported here represents the first effort toward engineering microorganisms for the conversion of FAs to the aforementioned products. PMID:20525863

  2. Microwave pyrolysis of distillers dried grain with solubles (DDGS) for biofuel production.

    PubMed

    Lei, Hanwu; Ren, Shoujie; Wang, Lu; Bu, Quan; Julson, James; Holladay, John; Ruan, Roger

    2011-05-01

    Microwave pyrolysis of distillers dried grain with solubles (DDGS) was investigated to determine the effects of pyrolytic conditions on the yields of bio-oil, syngas, and biochar. Pyrolysis process variables included reaction temperature, time, and power input. Microwave pyrolysis of DDGS was analyzed using response surface methodology to find out the effect of process variables on the biofuel (bio-oil and syngas) conversion yield and establish prediction models. Bio-oil recovery was in the range of 26.5-50.3 wt.% of the biomass. Biochar yields were 23.5-62.2% depending on the pyrolysis conditions. The energy content of DDGS bio-oils was 28 MJ/kg obtained at the 650°C and 8 min, which was about 66.7% of the heating value of gasoline. GC/MS analysis indicated that the biooil contained a series of important and useful chemical compounds: aliphatic and aromatic hydrocarbons. At least 13% of DDGS bio-oil was the same hydrocarbon compounds found in regular unleaded gasoline. PMID:21377870

  3. Microwave pyrolysis of distillers dried grain with solubles (DDGS) for biofuel production

    SciTech Connect

    Lei, Hanwu; Ren, Shoujie; Wang, Lu; Bu, Quan; Julson, James; Holladay, Johnathan E; Ruan, Roger

    2011-05-01

    Microwave pyrolysis of distillers dried grain with solubles (DDGS) was investigated to determine the effects of pyrolytic conditions on the yields of bio-oil, syngas, and biochar. Pyrolysis process variables included reaction temperature, time, and power input. Microwave pyrolysis of DDGS was analyzed using response surface methodology to find out the effect of process variables on the biofuel (bio-oil and syn- gas) conversion yield and establish prediction models. Bio-oil recovery was in the range of 26.5–50.3 wt.% of the biomass. Biochar yields were 23.5–62.2% depending on the pyrolysis conditions. The energy con- tent of DDGS bio-oils was 28 MJ/kg obtained at the 650 oC and 8 min, which was about 66.7% of the heat- ing value of gasoline. GC/MS analysis indicated that the biooil contained a series of important and useful chemical compounds: aliphatic and aromatic hydrocarbons. At least 13% of DDGS bio-oil was the same hydrocarbon compounds found in regular unleaded gasoline.

  4. Direct measurement and characterization of active photosynthesis zones inside biofuel producing and wastewater remediating microalgal biofilms

    SciTech Connect

    Bernstein, Hans C.; Kesaano, Maureen; Moll, Karen; Smith, Terence; Gerlach, Robin; Carlson, Ross; Miller, Charles D.; Peyton, Brent; Cooksey, Keith; Gardner, Robert D.; Sims, Ronald C.

    2014-03-01

    Abstract: Microalgal biofilm based technologies are of keen interest due to their high biomass concentrations and ability to utilize renewable resources, such as light and CO2. While photoautotrophic biofilms have long been used for wastewater remediation applications, biofuel production represents a relatively new and under-represented focus area. However, the direct measurement and characterization of fundamental parameters required for physiological analyses are challenging due to biofilm heterogeneity. This study evaluated oxygenic photosynthesis and biofuel precursor molecule production using a novel rotating algal biofilm reactor (RABR) operated at field- and laboratory-scales for wastewater remediation and biofuel production, respectively. Clear differences in oxygenic-photosynthesis, respiration and biofuel-precursor capacities were observed between the two systems and different conditions based on light and nitrogen availability. Nitrogen depletion was not found to have the same effect on lipid accumulation compared to prior planktonic studies. Physiological characterizations of these microalgal biofilms identify potential areas for future process optimization.

  5. Tailoring next-generation biofuels and their combustion in next-generation engines.

    SciTech Connect

    Gladden, John Michael; Wu, Weihua; Taatjes, Craig A.; Scheer, Adam Michael; Turner, Kevin M.; Yu, Eizadora T.; O'Bryan, Greg; Powell, Amy Jo; Gao, Connie W.

    2013-11-01

    Increasing energy costs, the dependence on foreign oil supplies, and environmental concerns have emphasized the need to produce sustainable renewable fuels and chemicals. The strategy for producing next-generation biofuels must include efficient processes for biomass conversion to liquid fuels and the fuels must be compatible with current and future engines. Unfortunately, biofuel development generally takes place without any consideration of combustion characteristics, and combustion scientists typically measure biofuels properties without any feedback to the production design. We seek to optimize the fuel/engine system by bringing combustion performance, specifically for advanced next-gene