Science.gov

Sample records for advanced biofuel production

  1. 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.

  2. Metabolic engineering for advanced biofuels production from Escherichia coli.

    PubMed

    Atsumi, Shota; Liao, James C

    2008-10-01

    Global energy and environmental problems have stimulated increasing efforts toward 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.

  3. 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

  4. Metabolic engineering of microbial pathways for advanced biofuels production.

    PubMed

    Zhang, Fuzhong; Rodriguez, Sarah; Keasling, Jay D

    2011-12-01

    Production of biofuels from renewable resources such as cellulosic biomass provides a source of liquid transportation fuel to replace petroleum-based fuels. This endeavor requires the conversion of cellulosic biomass into simple sugars, and the conversion of simple sugars into biofuels. Recently, microorganisms have been engineered to convert simple sugars into several types of biofuels, such as alcohols, fatty acid alkyl esters, alkanes, and terpenes, with high titers and yields. Here, we review recently engineered biosynthetic pathways from the well-characterized microorganisms Escherichia coli and Saccharomyces cerevisiae for the production of several advanced biofuels. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. 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.

  6. Microbial engineering for the production of advanced biofuels.

    PubMed

    Peralta-Yahya, Pamela P; Zhang, Fuzhong; del Cardayre, Stephen B; Keasling, Jay D

    2012-08-16

    Advanced biofuels produced by microorganisms have similar properties to petroleum-based fuels, and can 'drop in' to the existing transportation infrastructure. However, producing these biofuels in yields high enough to be useful requires the engineering of the microorganism's metabolism. Such engineering is not based on just one specific feedstock or host organism. Data-driven and synthetic-biology approaches can be used to optimize both the host and pathways to maximize fuel production. Despite some success, challenges still need to be met to move advanced biofuels towards commercialization, and to compete with more conventional fuels.

  7. 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).

  8. Advanced biofuel production by the yeast Saccharomyces cerevisiae.

    PubMed

    Buijs, Nicolaas A; Siewers, Verena; Nielsen, Jens

    2013-06-01

    Replacement of conventional transportation fuels with biofuels will require production of compounds that can cover the complete fuel spectrum, ranging from gasoline to kerosene. Advanced biofuels are expected to play an important role in replacing fossil fuels because they have improved properties compared with ethanol and some of these may have the energy density required for use in heavy duty vehicles, ships, and aviation. Moreover, advanced biofuels can be used as drop-in fuels in existing internal combustion engines. The yeast cell factory Saccharomyces cerevisiae can be turned into a producer of higher alcohols (1-butanol and isobutanol), sesquiterpenes (farnesene and bisabolene), and fatty acid ethyl esters (biodiesel), and here we discusses progress in metabolic engineering of S. cerevisiae for production of these advanced biofuels. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. 7 CFR 4288.137 - Succession and loss of control of advanced biofuel facilities and production.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 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 and loss of control of advanced biofuel facilities and production. (a) Contract succession. An entity who...

  10. 7 CFR 4288.137 - Succession and loss of control of advanced biofuel facilities and production.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 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 of advanced biofuel facilities and production. (a) Contract succession. An entity who becomes the eligible...

  11. 7 CFR 4288.137 - Succession and loss of control of advanced biofuel facilities and production.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 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 of advanced biofuel facilities and production. (a) Contract succession. An entity who becomes the eligible...

  12. Recent applications of metabolomics to advance microbial biofuel production.

    PubMed

    Martien, Julia I; Amador-Noguez, Daniel

    2017-02-01

    Biofuel production from plant biomass is a promising source of renewable energy [1]. However, efficient biofuel production involves the complex task of engineering high-performance microorganisms, which requires detailed knowledge of metabolic function and regulation. This review highlights the potential of mass-spectrometry-based metabolomic analysis to guide rational engineering of biofuel-producing microbes. We discuss recent studies that apply knowledge gained from metabolomic analyses to increase the productivity of engineered pathways, characterize the metabolism of emerging biofuel producers, generate novel bioproducts, enable utilization of lignocellulosic feedstock, and improve the stress tolerance of biofuel producers.

  13. Systems biology of yeast: enabling technology for development of cell factories for production of advanced biofuels.

    PubMed

    de Jong, Bouke; Siewers, Verena; Nielsen, Jens

    2012-08-01

    Transportation fuels will gradually shift from oil based fuels towards alternative fuel resources like biofuels. Current bioethanol and biodiesel can, however, not cover the increasing demand for biofuels and there is therefore a need for advanced biofuels with superior fuel properties. Novel cell factories will provide a production platform for advanced biofuels. However, deep cellular understanding is required for improvement of current biofuel cell factories. Fast screening and analysis (-omics) methods and metabolome-wide mathematical models are promising techniques. An integrated systems approach of these techniques drives diversity and quantity of several new biofuel compounds. This review will cover the recent technological developments that support improvement of the advanced biofuels 1-butanol, biodiesels and jetfuels.

  14. Recent trends in metabolic engineering of microorganisms for the production of advanced biofuels.

    PubMed

    Cheon, Seungwoo; Kim, Hye Mi; Gustavsson, Martin; Lee, Sang Yup

    2016-12-01

    As climate change has become one of the major global risks, our heavy dependence on petroleum-derived fuels has received much public attention. To solve such problems, production of sustainable fuels has been intensively studied over the past years. Thanks to recent advances in synthetic biology and metabolic engineering technologies, bio-based platforms for advanced biofuels production have been developed using various microorganisms. The strategies for production of advanced biofuels have converged upon four major metabolic routes: the 2-ketoacid pathway, the fatty acid synthesis (FAS) pathway, the isoprenoid pathway, and the reverse β-oxidation pathway. Additionally, the polyketide synthesis pathway has recently been attracting interest as a promising alternative biofuel production route. In this article, recent trends in advanced biofuels production are reviewed by categorizing them into three types of advanced biofuels: alcohols, biodiesel and jet fuel, and gasoline. Focus is given on the strategies of employing synthetic biology and metabolic engineering for the development of microbial strains producing advanced fuels. Finally, the prospects for future advances needed to achieve much more efficient bio-based production of advanced biofuels are discussed, focusing on designing advanced biofuel production pathways coupled with screening, modifying, and creating novel enzymes.

  15. Metabolic Engineering for Advanced Biofuels Production and Recent Advances Toward Commercialization.

    PubMed

    Meadows, Corey W; Kang, Aram; Lee, Taek S

    2017-07-21

    Research on renewable biofuels produced by microorganisms has enjoyed considerable advances in academic and industrial settings. As the renewable ethanol market approaches maturity, the demand is rising for the commercialization of more energy-dense fuel targets. Many strategies implemented in recent years have considerably increased the diversity and number of fuel targets that can be produced by microorganisms. Moreover, strain optimization for some of these fuel targets has ultimately led to their production at industrial scale. In this review, the recent metabolic engineering approaches for augmenting biofuel production derived from alcohols, isoprenoids, and fatty acids in several microorganisms are discussed. In addition, the successful commercialization ventures for each class of biofuel targets are discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. An energy-limited model of algal biofuel production: Toward the next generation of advanced biofuels

    DOE PAGES

    Dunlop, Eric H.; Coaldrake, A. Kimi; Silva, Cory S.; ...

    2013-10-22

    Algal biofuels are increasingly important as a source of renewable energy. The absence of reliable thermodynamic and other property data, and the large amount of kinetic data that would normally be required have created a major barrier to simulation. Additionally, the absence of a generally accepted flowsheet for biofuel production means that detailed simulation of the wrong approach is a real possibility. This model of algal biofuel production estimates the necessary data and places it into a heuristic model using a commercial simulator that back-calculates the process structure required. Furthermore, complex kinetics can be obviated for now by putting themore » simulator into energy limitation and forcing it to solve for the missing design variables, such as bioreactor surface area, productivity, and oil content. The model does not attempt to prescribe a particular approach, but provides a guide towards a sound engineering approach to this challenging and important problem.« less

  17. An energy-limited model of algal biofuel production: Toward the next generation of advanced biofuels

    SciTech Connect

    Dunlop, Eric H.; Coaldrake, A. Kimi; Silva, Cory S.; Seider, Warren D.

    2013-10-22

    Algal biofuels are increasingly important as a source of renewable energy. The absence of reliable thermodynamic and other property data, and the large amount of kinetic data that would normally be required have created a major barrier to simulation. Additionally, the absence of a generally accepted flowsheet for biofuel production means that detailed simulation of the wrong approach is a real possibility. This model of algal biofuel production estimates the necessary data and places it into a heuristic model using a commercial simulator that back-calculates the process structure required. Furthermore, complex kinetics can be obviated for now by putting the simulator into energy limitation and forcing it to solve for the missing design variables, such as bioreactor surface area, productivity, and oil content. The model does not attempt to prescribe a particular approach, but provides a guide towards a sound engineering approach to this challenging and important problem.

  18. 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.

  19. 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

  20. Microalgal triacylglycerols as feedstocks for biofuel production: perspectives and advances.

    PubMed

    Hu, Qiang; Sommerfeld, Milton; Jarvis, Eric; Ghirardi, Maria; Posewitz, Matthew; Seibert, Michael; Darzins, Al

    2008-05-01

    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.

  1. 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.

  2. 75 FR 21191 - Subpart B-Advanced Biofuel Payment Program; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-23

    ...--Advanced Biofuel Payment Program; Correction AGENCY: Rural Business-Cooperative Service, USDA. ACTION... existing advanced biofuel production and to encourage new production of advanced biofuels. As...

  3. Advanced Biofuels and Beyond: Chemistry Solutions for Propulsion and Production.

    PubMed

    Leitner, Walter; Klankermayer, Jürgen; Pischinger, Stefan; Pitsch, Heinz; Kohse-Höinghaus, Katharina

    2017-02-10

    Sustainably produced biofuels are being discussed intensively as one possible component in the energy scenarios for future ground transportation, especially when they are derived from lignocellulosic biomass. Traditionally, research activities on their production focus on the synthesis process, while leaving their combustion properties to subsequent evaluation by a different community. The present article adopts an integrative view of engine combustion and fuel synthesis, focusing on the chemical aspects as the common denominator. We wish to demonstrate that fundamental understanding of the combustion process can be instrumental to derive design criteria for the molecular structure of fuel candidates that can then be targets for the analysis of synthetic pathways and the development of catalytic production routes. With such an integrative approach to fuel design, it will be possible to improve systematically the entire system, spanning biomass feedstock, conversion process, fuel, engine, and pollutants with a perspective to improve the carbon footprint, increase efficiency, and reduce emissions of the transportation sector along the whole value chain.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  5. 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 CO₂ emissions. Several alternatives have been proposed to develop a sustainable industrial society and reduce greenhouse emissions. The idea of biological conversion of CO₂ to fuel and chemicals is receiving increased attention. In particular, the direct conversion of CO₂ 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.

  6. 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

  7. 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

  8. 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.

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

    DOE PAGES

    Torto-Alalibo, Trudy; Purwantini, Endang; Lomax, Jane; ...

    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

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. Tolerance engineering in bacteria for the production of advanced biofuels and chemicals.

    PubMed

    Mukhopadhyay, Aindrila

    2015-08-01

    During microbial production of solvent-like compounds, such as advanced biofuels and bulk chemicals, accumulation of the final product can negatively impact the cultivation of the host microbe and limit the production levels. Consequently, improving solvent tolerance is becoming an essential aspect of engineering microbial production strains. Mechanisms ranging from chaperones to transcriptional factors have been used to obtain solvent-tolerant strains. However, alleviating growth inhibition does not invariably result in increased production. Transporters specifically have emerged as a powerful category of proteins that bestow tolerance and often improve production but are difficult targets for cellular expression. Here we review strain engineering, primarily as it pertains to bacterial solvent tolerance, and the benefits and challenges associated with the expression of membrane-localized transporters in improving solvent tolerance and production. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. 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.

  16. 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.

  17. 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.

  18. National Alliance for Advanced Biofuels and Bio-Products Final Technical Report

    SciTech Connect

    Olivares, Jose A.; Baxter, Ivan; Brown, Judith; Carleton, Michael; Cattolico, Rose Anne; Taraka, Dale; Detter, John C.; Devarenne, Timothy P.; Dutcher, Susan K.; Fox, David T.; Goodenough, Ursula; Jaworski, Jan; Kramer, David; Lipton, Mary S.; McCormick, Margaret; Merchant, Sabeeha; Molnar, Istvan; Panisko, Ellen A.; Pellegrini, Matteo; Polle, Juergen; Sabarsky, Martin; Sayre, Richard T.; Starkenburg,, Shawn; Stormo, Gary; Twary, Scott N.; Unkefer, Clifford J.; Unkefer, Pat J.; Yuan, Joshua S.; Arnold, Bob; Bai, Xuemei; Boeing, Wiebke; Brown, Lois; Gujarathi, Ninad; Huesemann, Michael; Lammers, Pete; Laur, Paul; Khandan, Nirmala; Parsons, Ronald; Samocha, Tzachi; Thomasson, Alex; Unc, Adrian; Waller, Pete; Bonner, James; Coons, Jim; Fernando, Sandun; Goodall, Brian; Kadam, Kiran; Lacey, Ronald; Wei, Liu; Marrone, Babs; Nikolov, Zivko; Trewyn, Brian; Albrecht, Karl; Capareda, Sergio; Cheny, Scott; Deng, Shuguang; Elliott, Douglas; Cesar, Granda; Hallen, Richard; Lupton, Steven; Lynch, Sharry; Marchese, Anthony; Nieweg, Jennifer; Ogden, Kimberly; Oyler, James; Reardon, Ken; Roberts, William; Sams, David; Schaub, Tanner; Silks, Pete; Archibeque, Shawn; Foster, James; Gaitlan, Delbert; Lawrence, Addison; Lodge-Ivey, Shanna; Wickersham, Tyron; Blowers, Paul; Davis, Ryan; Downes, C. Meghan; Dunlop, Eric; Frank, Edward; Handler, Robert; Newby, Deborah; Pienkos, Philip; Richardson, James; Seider, Warren; Shonnard, David; Skaggs, Richard

    2014-09-30

    The main objective of NAABB was to combine science, technology, and engineering expertise from across the nation to break down critical technical barriers to commercialization of algae-based biofuels. The approach was to address technology development across the entire value chain of algal biofuels production, from selection of strains to cultivation, harvesting, extraction, fuel conversion, and agricultural coproduct production. Sustainable practices and financial feasibility assessments ununderscored the approach and drove the technology development.

  19. 76 FR 24343 - Advanced Biofuel Payment Program; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-02

    ... Service Rural Utilities Service 7 CFR Part 4288 RIN 0570-AA75 Advanced Biofuel Payment Program; Correction... Advanced Biofuel Payment Program authorized under the Food, Conservation, and Energy Act of 2008. This... contracts with advanced biofuel producers to pay such producers for the production of eligible...

  20. 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.

  1. 76 FR 7935 - Advanced Biofuel Payment Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-11

    ... ethanol facilities will produce gaseous advanced biofuels via anaerobic digesters. This biogas will be... producer'' provisions for determining whether an advanced biofuel producer of biogas or solid advanced biofuels is a ``larger producer'' or a ``smaller producer.'' For biogas and solid advanced biofuel, this...

  2. 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

  3. Oleaginous fungal lipid fermentation on combined acid- and alkali-pretreated corn stover hydrolysate for advanced biofuel production.

    PubMed

    Ruan, Zhenhua; Zanotti, Michael; Archer, Steven; Liao, Wei; Liu, Yan

    2014-07-01

    A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production.

  4. 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.

  5. Global Economic Effects of USA Biofuel Policy and the Potential Contribution from Advanced Biofuels

    SciTech Connect

    Gbadebo Oladosu; Keith Kline; Paul Leiby; Rocio Uria-Martinez; Maggie Davis; Mark Downing; Laurence Eaton

    2012-01-01

    This study evaluates the global economic effects of the USA renewable fuel standards (RFS2), and the potential contribution from advanced biofuels. Our simulation results imply that these mandates lead to an increase of 0.21 percent in the global gross domestic product (GDP) in 2022, including an increase of 0.8 percent in the USA and 0.02 percent in the rest of the world (ROW); relative to our baseline, no-RFS scenario. The incremental contributions to GDP from advanced biofuels in 2022 are estimated at 0.41 percent and 0.04 percent in the USA and ROW, respectively. Although production costs of advanced biofuels are higher than for conventional biofuels in our model, their economic benefits result from reductions in oil use, and their smaller impacts on food markets compared with conventional biofuels. Thus, the USA advanced biofuels targets are expected to have positive economic benefits.

  6. TERRA: Building New Communities for Advanced Biofuels

    SciTech Connect

    Cornelius, Joe; Mockler, Todd; Tuinstra, Mitch

    2016-03-01

    ARPA-E’s Transportation Energy Resources from Renewable Agriculture (TERRA) program is bringing together top experts from different disciplines – agriculture, robotics and data analytics – to rethink the production of advanced biofuel crops. ARPA-E Program Director Dr. Joe Cornelius discusses the TERRA program and explains how ARPA-E’s model enables multidisciplinary collaboration among diverse communities. The video focuses on two TERRA projects—Donald Danforth Center and Purdue University—that are developing and integrating cutting-edge remote sensing platforms, complex data analytics tools and plant breeding technologies to tackle the challenge of sustainably increasing biofuel stocks.

  7. Advances in microalgae engineering and synthetic biology applications for biofuel production.

    PubMed

    Gimpel, Javier A; Specht, Elizabeth A; Georgianna, D Ryan; Mayfield, Stephen P

    2013-06-01

    Among the technologies being examined to produce renewable fuels, microalgae are viewed by many in the scientific community as having the greatest potential to become economically viable. Algae are capable of producing greater than 50,000 kg/acre/year of biomass [1]. Additionally, most algae naturally accumulate energy-dense oils that can easily be converted into transportation fuels. To reach economic parity with fossil fuels there are still several challenges. These include identifying crop protection strategies, improving harvesting and oil extraction processes, and increasing biomass productivity and oil content. All of these challenges can be impacted by genetic, molecular, and ultimately synthetic biology techniques, and all of these technologies are being deployed to enable algal biofuels to become economically competitive with fossil fuels.

  8. Reassessing Escherichia coli as a cell factory for biofuel production.

    PubMed

    Wang, Chonglong; Pfleger, Brian F; Kim, Seon-Won

    2017-03-11

    Via metabolic engineering, industrial microorganisms have the potential to convert renewable substrates into a wide range of biofuels that can address energy security and environmental challenges associated with current fossil fuels. The user-friendly bacterium, Escherichia coli, remains one of the most frequently used hosts for demonstrating production of biofuel candidates including alcohol-, fatty acid- and terpenoid-based biofuels. In this review, we summarize the metabolic pathways for synthesis of these biofuels and assess enabling technologies that assist in regulating biofuel synthesis pathways and rapidly assembling novel E. coli strains. These advances maintain E. coli's position as a prominent host for developing cell factories for biofuel production.

  9. 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. © The Author(s) 2014.

  10. Montana Advanced Biofuels Great Falls Approval

    EPA Pesticide Factsheets

    This November 20, 2015 letter from EPA approves the petition from Montana Advanced Biofuels, LLC, Great Falls facility, regarding ethanol produced through a dry mill process, qualifying under the Clean Air Act for advanced biofuel (D-code 5) and renewable

  11. Biofuels and biodiversity: principles for creating better policies for biofuel production.

    PubMed

    Groom, Martha J; Gray, Elizabeth M; Townsend, Patricia A

    2008-06-01

    Biofuels are a new priority in efforts to reduce dependence on fossil fuels; nevertheless, the rapid increase in production of biofuel feedstock may threaten biodiversity. There are general principles that should be used in developing guidelines for certifying biodiversity-friendly biofuels. First, biofuel feedstocks should be grown with environmentally safe and biodiversity-friendly agricultural practices. The sustainability of any biofuel feedstock depends on good growing practices and sound environmental practices throughout the fuel-production life cycle. Second, the ecological footprint of a biofuel, in terms of the land area needed to grow sufficient quantities of the feedstock, should be minimized. The best alternatives appear to be fuels of the future, especially fuels derived from microalgae. Third, biofuels that can sequester carbon or that have a negative or zero carbon balance when viewed over the entire production life cycle should be given high priority. Corn-based ethanol is the worst among the alternatives that are available at present, although this is the biofuel that is most advanced for commercial production in the United States. We urge aggressive pursuit of alternatives to corn as a biofuel feedstock. Conservation biologists can significantly broaden and deepen efforts to develop sustainable fuels by playing active roles in pursuing research on biodiversity-friendly biofuel production practices and by helping define biodiversity-friendly biofuel certification standards.

  12. 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.

  13. TERRA: Building New Communities for Advanced Biofuels

    ScienceCinema

    Cornelius, Joe; Mockler, Todd; Tuinstra, Mitch

    2016-07-12

    ARPA-E’s Transportation Energy Resources from Renewable Agriculture (TERRA) program is bringing together top experts from different disciplines – agriculture, robotics and data analytics – to rethink the production of advanced biofuel crops. ARPA-E Program Director Dr. Joe Cornelius discusses the TERRA program and explains how ARPA-E’s model enables multidisciplinary collaboration among diverse communities. The video focuses on two TERRA projects—Donald Danforth Center and Purdue University—that are developing and integrating cutting-edge remote sensing platforms, complex data analytics tools and plant breeding technologies to tackle the challenge of sustainably increasing biofuel stocks.

  14. 77 FR 5229 - Notice of Contract Proposals (NOCP) for Payments to Eligible Advanced Biofuel Producers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-02

    ... Payments to Eligible Advanced Biofuel Producers AGENCY: Rural Business-Cooperative Service and Rural... availability of up to $25 million to make payments to advanced biofuel producers for the production of eligible... participating in the Advanced Biofuel Payment Program for Fiscal Year 2012 were accepted from October 1,...

  15. Alternative Crops and Biofuel Production

    SciTech Connect

    Kenkel, Philip; Holcomb, Rodney B.

    2013-03-01

    In order for the biofuel industry to meet the RFS benchmarks for biofuels, new feedstock sources and production systems will have to be identified and evaluated. The Southern Plains has the potential to produce over a billion gallons of biofuels from regionally produced alternative crops, agricultural residues, and animal fats. While information on biofuel conversion processes is available, it is difficult for entrepreneurs, community planners and other interested individuals to determine the feasibility of biofuel processes or to match production alternatives with feed stock availability and community infrastructure. This project facilitates the development of biofuel production from these regionally available feed stocks. Project activities are concentrated in five major areas. The first component focused on demonstrating the supply of biofuel feedstocks. This involves modeling the yield and cost of production of dedicated energy crops at the county level. In 1991 the DOE selected switchgrass as a renewable source to produce transportation fuel after extensive evaluations of many plant species in multiple location (Caddel et al,. 2010). However, data on the yield and cost of production of switchgrass are limited. This deficiency in demonstrating the supply of biofuel feedstocks was addressed by modeling the potential supply and geographic variability of switchgrass yields based on relationship of available switchgrass yields to the yields of other forage crops. This model made it possible to create a database of projected switchgrass yields for five different soil types at the county level. A major advantage of this methodology is that the supply projections can be easily updated as improved varieties of switchgrass are developed and additional yield data becomes available. The modeling techniques are illustrated using the geographic area of Oklahoma. A summary of the regional supply is then provided.

  16. A Survey of Biofuel Production potentials in Russia

    NASA Astrophysics Data System (ADS)

    Lykova, Natalya; Gustafsson, Jan-Erik

    2010-01-01

    Due to the abundance of fossil fuel resources in Russia, the development of the renewable energy market there was delayed. Recent technological advancement has led to an increasing interest in biofuel production. The aim of research was to evaluate how biofuels are introduced into the current energy scheme of the country. The potential production of biofuels was estimated based on sustainable approaches which provide solution for carbon emission reduction and environmental benefits. Russia still requires biofuel policy to make biofuels compatible with traditional fossil fuels.

  17. Center for Advanced Biofuel Systems (CABS) Final Report

    SciTech Connect

    Kutchan, Toni M.

    2015-12-02

    One of the great challenges facing current and future generations is how to meet growing energy demands in an environmentally sustainable manner. Renewable energy sources, including wind, geothermal, solar, hydroelectric, and biofuel energy systems, are rapidly being developed as sustainable alternatives to fossil fuels. Biofuels are particularly attractive to the U.S., given its vast agricultural resources. The first generation of biofuel systems was based on fermentation of sugars to produce ethanol, typically from food crops. Subsequent generations of biofuel systems, including those included in the CABS project, will build upon the experiences learned from those early research results and will have improved production efficiencies, reduced environmental impacts and decreased reliance on food crops. Thermodynamic models predict that the next generations of biofuel systems will yield three- to five-fold more recoverable energy products. To address the technological challenges necessary to develop enhanced biofuel systems, greater understanding of the non-equilibrium processes involved in solar energy conversion and the channeling of reduced carbon into biofuel products must be developed. The objective of the proposed Center for Advanced Biofuel Systems (CABS) was to increase the thermodynamic and kinetic efficiency of select plant- and algal-based fuel production systems using rational metabolic engineering approaches grounded in modern systems biology. The overall strategy was to increase the efficiency of solar energy conversion into oils and other specialty biofuel components by channeling metabolic flux toward products using advanced catalysts and sensible design:1) employing novel protein catalysts that increase the thermodynamic and kinetic efficiencies of photosynthesis and oil biosynthesis; 2) engineering metabolic networks to enhance acetyl-CoA production and its channeling towards lipid synthesis; and 3) engineering new metabolic networks for the

  18. 78 FR 34975 - Notice of Contract Proposals (NOCP) for the Advanced Biofuels Payment Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-11

    ... availability of $98.6 million to make payments to advanced biofuel producers for the production of eligible... Appropriations Act, 2013, Public Law 113-6. DATES: Applications for participating in the Advanced Biofuel Payment... be submitted in accordance with 7 CFR 4288, Subpart B, section 4288.130(d). The Biofuel...

  19. Drop-in biofuel production via conventional (lipid/fatty acid) and advanced (biomass) routes. Part I

    DOE PAGES

    Karatzos, Sergios; van Dyk, J. Susan; McMillan, James D.; ...

    2017-01-23

    Drop-in biofuels that are 'functionally identical to petroleum fuels and fully compatible with existing infrastructure' are needed for sectors such as aviation where biofuels such as bioethanol/biodiesel cannot be used. The technologies used to produce drop-in biofuels can be grouped into the four categories: oleochemical, thermochemical, biochemical, and hybrid technologies. Commercial volumes of conventional drop-in biofuels are currently produced through the oleochemical pathway, to make products such as renewable diesel and biojet fuel. However, the cost, sustainability, and availability of the lipid/fatty acid feedstocks are significant challenges that need to be addressed. In the longer-term, it is likely that commercialmore » growth in drop-in biofuels will be based on lignocellulosic feedstocks. However, these technologies have been slow to develop and have been hampered by several technoeconomic challenges. For example, the gasification/Fischer-Tropsch (FT) synthesis route suffers from high capital costs and economies of scale difficulties, while the economical production of high quality syngas remains a significant challenge. Although pyrolysis/hydrothermal liquefaction (HTL) based technologies are promising, the upgrading of pyrolysis oils to higher specification fuels has encountered several technical challenges, such as high catalyst cost and short catalyst lifespan. Biochemical routes to drop-in fuels have the advantage of producing single molecules with simple chemistry. Moreover, the high value of these molecules in other markets such as renewable chemical precursors and fragrances will limit their use for fuel. In the near-term, (1-5 years) it is likely that, 'conventional' drop-in biofuels will be produced predominantly via the oleochemical route, due to the relative simplicity and maturity of this pathway.« less

  20. 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.

  1. 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.

  2. Advancing Biofuels: Balancing for Sustainability

    USDA-ARS?s Scientific Manuscript database

    As with most technologies, use of biofuels has both benefits and risks, which vary by feedstock. Expected benefits include increased energy independence, reduced consumption of fossil fuels, reduced emission of greenhouse gases and invigorated rural economies. Anticipated risks include potential com...

  3. Challenges in engineering microbes for biofuels production.

    PubMed

    Stephanopoulos, Gregory

    2007-02-09

    Economic and geopolitical factors (high oil prices, environmental concerns, and supply instability) have been prompting policy-makers to put added emphasis on renewable energy sources. For the scientific community, recent advances, embodied in new insights into basic biology and technology that can be applied to metabolic engineering, are generating considerable excitement. There is justified optimism that the full potential of biofuel production from cellulosic biomass will be obtainable in the next 10 to 15 years.

  4. Fostering sustainable feedstock production for advanced biofuels on underutilised land in Europe

    NASA Astrophysics Data System (ADS)

    Mergner, Rita; Janssen, Rainer; Rutz, Dominik; Knoche, Dirk; Köhler, Raul; Colangeli, Marco; Gyuris, Peter

    2017-04-01

    Background In context of growing competition between land uses, bioenergy development is often seen as one of possible contributors to such competition. However, the potential of underutilized land (contaminated, abandoned, marginal, fallow land etc.) which is not used or cannot be used for productive activities is not exhausted and offers an attractive alternative for sustainable production of different biomass feedstocks in Europe. Depending on biomass feedstocks, different remediation activities can be carried out in addition. Bioenergy crops have the potential to be grown profitably on underutilized land and can therefore offer an attractive source of income on the local level contributing to achieving the targets of the Renewable Energy Directive (EC/2009). The FORBIO project The FORBIO project demonstrates the viability of using underutilised land in EU Member States for sustainable bioenergy feedstock production that does not affect the supply of food, feed and land currently used for recreational or conservation purposes. Project activities will serve to build up and strengthen local bioenergy value chains that are competitive and that meet the highest sustainability standards, thus contributing to the market uptake of sustainable bioenergy in the EU. Presented results The FORBIO project will develop a methodology to assess the sustainable bioenergy production potential on available underutilized lands in Europe at local, site-specific level. Based on this methodology, the project will produce multiple feasibility studies in three selected case study locations: Germany (lignite mining and sewage irrigation fields in the metropolis region of Berlin and Brandenburg), Italy (contaminated land from industrial activities in Sulcis, Portoscuso) and Ukraine (underutilised marginal agricultural land in the North of Kiev). The focus of the presentation will be on the agronomic and techno-economic feasibility studies in Germany, Italy and Ukraine. Agronomic

  5. 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

  6. Techno-economic analysis of advanced biofuel production based on bio-oil gasification.

    PubMed

    Li, Qi; Zhang, Yanan; Hu, Guiping

    2015-09-01

    This paper evaluates the economic feasibility of an integrated production pathway combining fast pyrolysis and bio-oil gasification. The conversion process is simulated with Aspen Plus® for a 2000 metric ton per day facility. Techno-economic analysis of this integrated pathway has been conducted. A total capital investment of $510 million has been estimated and the minimum fuel selling price (MSP) is $5.59 per gallon of gasoline equivalent. The sensitivity analysis shows that the MSP is most sensitive to internal rate of return, fuel yield, biomass feedstock cost, and fixed capital investment. Monte-Carlo simulation shows that MSP for bio-oil gasification would be more than $6/gal with a probability of 0.24, which indicates this pathway is still at high risk with current economic and technical situation.

  7. Anaerobic gut fungi: Advances in isolation, culture, and cellulolytic enzyme discovery for biofuel production.

    PubMed

    Haitjema, Charles H; Solomon, Kevin V; Henske, John K; Theodorou, Michael K; O'Malley, Michelle A

    2014-08-01

    Anaerobic gut fungi are an early branching family of fungi that are commonly found in the digestive tract of ruminants and monogastric herbivores. It is becoming increasingly clear that they are the primary colonizers of ingested plant biomass, and that they significantly contribute to the decomposition of plant biomass into fermentable sugars. As such, anaerobic fungi harbor a rich reservoir of undiscovered cellulolytic enzymes and enzyme complexes that can potentially transform the conversion of lignocellulose into bioenergy products. Despite their unique evolutionary history and cellulolytic activity, few species have been isolated and studied in great detail. As a result, their life cycle, cellular physiology, genetics, and cellulolytic metabolism remain poorly understood compared to aerobic fungi. To help address this limitation, this review briefly summarizes the current body of knowledge pertaining to anaerobic fungal biology, and describes progress made in the isolation, cultivation, molecular characterization, and long-term preservation of these microbes. We also discuss recent cellulase- and cellulosome-discovery efforts from gut fungi, and how these interesting, non-model microbes could be further adapted for biotechnology applications. © 2014 Wiley Periodicals, Inc.

  8. Transition Metal Phosphide Nanoparticles Supported on SBA-15 as Highly Selective Hydrodeoxygenation Catalysts for the Production of Advanced Biofuels.

    PubMed

    Yang, Yongxing; Ochoa-Hernández, Cristina; de la Peña O'Shea, Víctor A; Pizarro, Patricia; Coronado, Juan M; Serrano, David P

    2015-09-01

    for hydrodeoxygenation MoP/SBA-15 appears as a very promising catalyst for the production of advanced biofuels.

  9. Engineering algae for biohydrogen and biofuel production.

    PubMed

    Beer, Laura L; Boyd, Eric S; Peters, John W; Posewitz, Matthew C

    2009-06-01

    There is currently substantial interest in utilizing eukaryotic algae for the renewable production of several bioenergy carriers, including starches for alcohols, lipids for diesel fuel surrogates, and H2 for fuel cells. Relative to terrestrial biofuel feedstocks, algae can convert solar energy into fuels at higher photosynthetic efficiencies, and can thrive in salt water systems. Recently, there has been considerable progress in identifying relevant bioenergy genes and pathways in microalgae, and powerful genetic techniques have been developed to engineer some strains via the targeted disruption of endogenous genes and/or transgene expression. Collectively, the progress that has been realized in these areas is rapidly advancing our ability to genetically optimize the production of targeted biofuels.

  10. Recent advances in engineering propionyl-CoA metabolism for microbial production of value-added chemicals and biofuels.

    PubMed

    Srirangan, Kajan; Bruder, Mark; Akawi, Lamees; Miscevic, Dragan; Kilpatrick, Shane; Moo-Young, Murray; Chou, C Perry

    2016-08-25

    Diminishing fossil fuel reserves and mounting environmental concerns associated with petrochemical manufacturing practices have generated significant interests in developing whole-cell biocatalytic systems for the production of value-added chemicals and biofuels. Although acetyl-CoA is a common natural biogenic precursor for the biosynthesis of numerous metabolites, propionyl-CoA is unpopular and non-native to most organisms. Nevertheless, with its C3-acyl moiety as a discrete building block, propionyl-CoA can serve as another key biogenic precursor to several biological products of industrial importance. As a result, engineering propionyl-CoA metabolism, particularly in genetically tractable hosts with the use of inexpensive feedstocks, has paved an avenue for novel biomanufacturing. Herein, we present a systematic review on manipulation of propionyl-CoA metabolism as well as relevant genetic and metabolic engineering strategies for microbial production of value-added chemicals and biofuels, including odd-chain alcohols and organic acids, bio(co)polymers and polyketides. [Formula: see text].

  11. National Advanced Biofuels Consortium (NABC), Biofuels for Advancing America (Fact Sheet)

    SciTech Connect

    Not Available

    2010-06-01

    Introduction to the National Advanced Biofuels Consortium, a collaboration between 17 national laboratory, university, and industry partners that is conducting cutting-edge research to develop infrastructure-compatible, sustainable, biomass-based hydrocarbon fuels.

  12. 75 FR 11836 - Bioenergy Program for Advanced Biofuels

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... advanced biofuel produced from October 1, 2008 through September 30, 2009. SUMMARY: RBS is announcing additional payments to advanced biofuel producers determined eligible in Fiscal Year 2009 for the Bioenergy... executed contract, but did not submit a request for payment for the advanced biofuel produced in FY...

  13. Engineering industrial yeast for renewable advanced biofuels applications

    USDA-ARS?s Scientific Manuscript database

    The industrial yeast Saccharomyces cerevisiae is a candidate for the next-generation biocatalyst development due to its unique genomic background and robust performance in fermentation-based production. In order to meet challenges of renewable and sustainable advanced biofuels conversion including ...

  14. 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.

  15. 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

  16. 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

  17. Coupling of algal biofuel production with wastewater.

    PubMed

    Bhatt, Neha Chamoli; 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.

  18. 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

  19. 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. © 2014 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  20. 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.

  1. Systems analysis and futuristic designs of advanced biofuel factory concepts.

    SciTech Connect

    Chianelli, Russ; Leathers, James; Thoma, Steven George; Celina, Mathias Christopher; Gupta, Vipin P.

    2007-10-01

    The U.S. is addicted to petroleum--a dependency that periodically shocks the economy, compromises national security, and adversely affects the environment. If liquid fuels remain the main energy source for U.S. transportation for the foreseeable future, the system solution is the production of new liquid fuels that can directly displace diesel and gasoline. This study focuses on advanced concepts for biofuel factory production, describing three design concepts: biopetroleum, biodiesel, and higher alcohols. A general schematic is illustrated for each concept with technical description and analysis for each factory design. Looking beyond current biofuel pursuits by industry, this study explores unconventional feedstocks (e.g., extremophiles), out-of-favor reaction processes (e.g., radiation-induced catalytic cracking), and production of new fuel sources traditionally deemed undesirable (e.g., fusel oils). These concepts lay the foundation and path for future basic science and applied engineering to displace petroleum as a transportation energy source for good.

  2. Review of the cultivation program within the national alliance for advanced biofuels and bioproducts

    USDA-ARS?s Scientific Manuscript database

    The cultivation efforts within the National Alliance for Advanced Biofuels and Bioproducts (NAABB) were developed to provide four major goals for the consortium, which included biomass production for downstream experimentation, development of new assessment tools for cultivation, development of new ...

  3. 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.

  4. 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.

  5. 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

  6. Biofuel production by recombinant microorganisms

    DOEpatents

    Liao, James C.; Atsumi, Shota; Cann, Anthony F.

    2017-07-04

    Provided herein are metabolically-modified microorganisms useful for producing biofuels. More specifically, provided herein are methods of producing high alcohols including isobutanol, 1-butanol, 1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-phenylethanol from a suitable substrate.

  7. 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.

  8. 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

  9. Potential of biofilm-based biofuel production.

    PubMed

    Wang, Zhi-Wu; Chen, Shulin

    2009-05-01

    Biofilm technology has been extensively applied to wastewater treatment, but its potential application in biofuel production has not been explored. Current technologies of converting lignocellulose materials to biofuel are hampered by costly processing steps in pretreatment, saccharification, and product recovery. Biofilms may have a potential to improve efficiency of these processes. Advantages of biofilms include concentration of cell-associated hydrolytic enzymes at the biofilm-substrate interface to increase reaction rates, a layered microbial structure in which multiple species may sequentially convert complex substrates and coferment hexose and pentose as hydrolysates diffuse outward, and the possibility of fungal-bacterial symbioses that allow simultaneous delignification and saccharification. More importantly, the confined microenvironment within a biofilm selectively rewards cells with better phenotypes conferred from intercellular gene or signal exchange, a process which is absent in suspended cultures. The immobilized property of biofilm, especially when affixed to a membrane, simplifies the separation of biofuel from its producer and promotes retention of biomass for continued reaction in the fermenter. Highly consolidated bioprocessing, including delignification, saccharification, fermentation, and separation in a single reactor, may be possible through the application of biofilm technology. To date, solid-state fermentation is the only biofuel process to which the advantages of biofilms have been applied, even though it has received limited attention and improvements. The transfer of biofilm technology from environmental engineering has the potential to spur great innovations in the optimization of biofuel production.

  10. Role of Escherichia coli in Biofuel Production.

    PubMed

    Koppolu, Veerendra; Vasigala, Veneela Kr

    2016-01-01

    Increased energy consumption coupled with depleting petroleum reserves and increased greenhouse gas emissions have renewed our interest in generating fuels from renewable energy sources via microbial fermentation. Central to this problem is the choice of microorganism that catalyzes the production of fuels at high volumetric productivity and yield from cheap and abundantly available renewable energy sources. Microorganisms that are metabolically engineered to redirect renewable carbon sources into desired fuel products are contemplated as best choices to obtain high volumetric productivity and yield. Considering the availability of vast knowledge in genomic and metabolic fronts, Escherichia coli is regarded as a primary choice for the production of biofuels. Here, we reviewed the microbial production of liquid biofuels that have the potential to be used either alone or in combination with the present-day fuels. We specifically highlighted the metabolic engineering and synthetic biology approaches used to improve the production of biofuels from E. coli over the past few years. We also discussed the challenges that still exist for the biofuel production from E. coli and their possible solutions.

  11. Role of Escherichia coli in Biofuel Production

    PubMed Central

    Koppolu, Veerendra; Vasigala, Veneela KR

    2016-01-01

    Increased energy consumption coupled with depleting petroleum reserves and increased greenhouse gas emissions have renewed our interest in generating fuels from renewable energy sources via microbial fermentation. Central to this problem is the choice of microorganism that catalyzes the production of fuels at high volumetric productivity and yield from cheap and abundantly available renewable energy sources. Microorganisms that are metabolically engineered to redirect renewable carbon sources into desired fuel products are contemplated as best choices to obtain high volumetric productivity and yield. Considering the availability of vast knowledge in genomic and metabolic fronts, Escherichia coli is regarded as a primary choice for the production of biofuels. Here, we reviewed the microbial production of liquid biofuels that have the potential to be used either alone or in combination with the present-day fuels. We specifically highlighted the metabolic engineering and synthetic biology approaches used to improve the production of biofuels from E. coli over the past few years. We also discussed the challenges that still exist for the biofuel production from E. coli and their possible solutions. PMID:27441002

  12. 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.

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

    USDA-ARS?s Scientific Manuscript database

    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 ...

  14. 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.

  15. Life cycle assessment of cellulosic and advanced biofuel crops

    USDA-ARS?s Scientific Manuscript database

    Estimating the carbon intensity of biofuel production is important in order to meet greenhouse gas (GHG) targets set by government policy. Nitrous oxide emissions are the largest source and soil carbon the largest sink of GHGs for determining the carbon intensity of biofuels during their production ...

  16. Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies

    SciTech Connect

    Soloiu, Valentin A.

    2012-03-31

    The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.

  17. Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies

    SciTech Connect

    Soloiu, Valentin

    2012-03-31

    The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.

  18. Laccase applications in biofuels production: current status and future prospects.

    PubMed

    Kudanga, Tukayi; Le Roes-Hill, Marilize

    2014-08-01

    The desire to reduce dependence on the ever diminishing fossil fuel reserves coupled with the impetus towards green energy has seen increased research in biofuels as alternative sources of energy. Lignocellulose materials are one of the most promising feedstocks for advanced biofuels production. However, their utilisation is dependent on the efficient hydrolysis of polysaccharides, which in part is dependent on cost-effective and benign pretreatment of biomass to remove or modify lignin and release or expose sugars to hydrolytic enzymes. Laccase is one of the enzymes that are being investigated not only for potential use as pretreatment agents in biofuel production, mainly as a delignifying enzyme, but also as a biotechnological tool for removal of inhibitors (mainly phenolic) of subsequent enzymatic processes. The current review discusses the major advances in the application of laccase as a potential pretreatment strategy, the underlying principles as well as directions for future research in the search for better enzyme-based technologies for biofuel production. Future perspectives could include synergy between enzymes that may be required for optimal results and the adoption of the biorefinery concept in line with the move towards the global implementation of the bioeconomy strategy.

  19. Enzymatic biofuel cells: 30 years of critical advancements.

    PubMed

    Rasmussen, Michelle; Abdellaoui, Sofiene; Minteer, Shelley D

    2016-02-15

    Enzymatic biofuel cells are bioelectronic devices that utilize oxidoreductase enzymes to catalyze the conversion of chemical energy into electrical energy. This review details the advancements in the field of enzymatic biofuel cells over the last 30 years. These advancements include strategies for improving operational stability and electrochemical performance, as well as device fabrication for a variety of applications, including implantable biofuel cells and self-powered sensors. It also discusses the current scientific and engineering challenges in the field that will need to be addressed in the future for commercial viability of the technology.

  20. Exploring new strategies for cellulosic biofuels production

    Treesearch

    Paul Langan; S. Gnankaran; Kirk D. Rector; Norma Pawley; David T. Fox; Dae Won Cho; Kenneth E. Hammel

    2011-01-01

    A research program has been initiated to formulate new strategies for efficient low-cost lignocellulosic biomass processing technologies for the production of biofuels. This article reviews results from initial research into lignocellulosic biomass structure, recalcitrance, and pretreatment. In addition to contributing towards a comprehensive understanding of...

  1. 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...

  2. 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...

  3. 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.

  4. Enzymatic deconstruction of xylan for biofuel production.

    PubMed

    Dodd, Dylan; Cann, Isaac K O

    2009-02-18

    The combustion of fossil-derived fuels has a significant impact on atmospheric carbon dioxide (CO(2)) 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 CO(2) 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.

  5. 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

  6. Yeast synthetic biology toolbox and applications for biofuel production.

    PubMed

    Tsai, Ching-Sung; Kwak, Suryang; Turner, Timothy L; Jin, Yong-Su

    2015-02-01

    Yeasts are efficient biofuel producers with numerous advantages outcompeting bacterial counterparts. While most synthetic biology tools have been developed and customized for bacteria especially for Escherichia coli, yeast synthetic biological tools have been exploited for improving yeast to produce fuels and chemicals from renewable biomass. Here we review the current status of synthetic biological tools and their applications for biofuel production, focusing on the model strain Saccharomyces cerevisiae We describe assembly techniques that have been developed for constructing genes, pathways, and genomes in yeast. Moreover, we discuss synthetic parts for allowing precise control of gene expression at both transcriptional and translational levels. Applications of these synthetic biological approaches have led to identification of effective gene targets that are responsible for desirable traits, such as cellulosic sugar utilization, advanced biofuel production, and enhanced tolerance against toxic products for biofuel production from renewable biomass. Although an array of synthetic biology tools and devices are available, we observed some gaps existing in tool development to achieve industrial utilization. Looking forward, future tool development should focus on industrial cultivation conditions utilizing industrial strains.

  7. Three generation production biotechnology of biomass into bio-fuel

    NASA Astrophysics Data System (ADS)

    Zheng, Chaocheng

    2017-08-01

    The great change of climate change, depletion of natural resources, and scarcity of fossil fuel in the whole world nowadays have witnessed a sense of urgency home and abroad among scales of researchers, development practitioners, and industrialists to search for completely brand new sustainable solutions in the area of biomass transforming into bio-fuels attributing to our duty-that is, it is our responsibility to take up this challenge to secure our energy in the near future with the help of sustainable approaches and technological advancements to produce greener fuel from nature organic sources or biomass which comes generally from organic natural matters such as trees, woods, manure, sewage sludge, grass cuttings, and timber waste with a source of huge green energy called bio-fuel. Biomass includes most of the biological materials, livings or dead bodies. This energy source is ripely used industrially, or domestically for rather many years, but the recent trend is on the production of green fuel with different advance processing systems in a greener. More sustainable method. Biomass is becoming a booming industry currently on account of its cheaper cost and abundant resources all around, making it fairly more effective for the sustainable use of the bio-energy. In the past few years, the world has witnessed a remarkable development in the bio-fuel production technology, and three generations of bio-fuel have already existed in our society. The combination of membrane technology with the existing process line can play a vital role for the production of green fuel in a sustainable manner. In this paper, the science and technology for sustainable bio-fuel production will be introduced in detail for a cleaner world.

  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

    2016-02-29

    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.

  9. Partnering with Industry to Advance Biofuels and Bioproducts (Fact Sheet)

    SciTech Connect

    Not Available

    2011-12-01

    Fact sheet describing NREL's Integrated Biorefinery Research Facility, a biochemical pilot plant and partnership facility containing equipment and lab space for pretreatement, enzymatic hydrolysis, fermentation, compositional analysis, and downstream processing. For more than 30 years, the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) has been at the leading edge of research and technology advancements to develop renewable fuels and bioproducts. NREL works to develop cost-competitive alternatives to conventional transportation fuels and value-added biobased chemicals that can be used to manufacture clothing, plastics, lubricants, and other products. NREL is developing technologies and processes to produce a range of sustainable, energy-dense advanced biofuels that are compatible with our existing transportation fuel infrastructure. As part of that effort, NREL's National Bioenergy Center has entered into more than 90 collaborations in the past five years with companies ranging in size from start-ups to those that appear on Fortune magazine's Fortune 100 list. The new Integrated Biorefinery Research Facility (IBRF) showcases NREL's commitment to collaboration and to meeting the nation's biofuels and bioproducts development and deployment goals. Designed to speed the growth of the biofuels and bioproducts industries, the IBRF is a unique $33.5 million pilot facility capable of supporting a variety of projects. The IBRF is available to industry partners who work with NREL through cooperative research and development, technical, and analytical service agreements. With 27,000 ft2 of high bay space, the IBRF provides industry partners with the opportunity to operate, test, and develop their own biorefining technology and equipment.

  10. 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. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  11. 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

  12. Genetic engineering of algae for enhanced biofuel production.

    PubMed

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

    2010-04-01

    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 H(2) 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 H(2) 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.

  13. Policy options to support biofuel production.

    PubMed

    Mabee, W E

    2007-01-01

    Biofuels for use in the transportation sector have been produced on a significant scale since the 1970s, using a variety of technologies. The biofuels widely available today are predominantly sugar- and starch-based bioethanol, and oilseed- and waste oil-based biodiesel, although new technologies under development may allow the use of lignocellulosic feedstocks. Measures to promote the use of biofuels include renewable fuel mandates, tax incentives, and direct funding for capital projects or fleet upgrades. This paper provides a review of the policies behind the successful establishment of the biofuel industry in countries around the world. The impact of direct funding programs and excise tax exemptions are examined using the United States as a case study. It is found that the success of five major bioethanol producing states (Illinois, Iowa, Nebraska, South Dakota, and Minnesota) is closely related to the presence of funding designed to support the industry in its start-up phase, while tax exemptions on bioethanol use do not influence the development of production capacity. The study concludes that successful policy interventions can take many forms, but that success is equally dependent upon external factors, which include biomass availability, an active industry, and competitive energy prices.

  14. 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. © 2014 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

  15. Integrated Biorefinery for Biofuels Production

    SciTech Connect

    Miller, Gabriel

    2011-09-02

    This project has focused on very low grade fats, oil and greases found in municipal, commercial and industrial facilities around the country. These wastes are often disposed in landfills, wastewater treatment plants or farm fields or are blended illegally into animal feeds. Using any of these waste fatty materials that are unfit for human or animal nutrition as a clean alternative fuel makes good sense. This project defines the aforementioned wastes in terms of quality and prevalence in the US, then builds on specific promising pathways for utilizing these carbon neutral wastes. These pathways are discussed and researched at bench-scale, and in one instance, at pilot-scale. The three primary pathways are as follows: The production of Renewable Diesel Oil (RDO) as a stand-alone fuel or blended with standard distillate or residual hydrocarbons; The production of RDO as a platform for the further manufacture of Biodiesel utilizing acid esterification; The production of RDO as a platform for the manufacture of an ASTM Diesel Fuel using one or more catalysts to effect a decarboxylation of the carboxylics present in RDO This study shows that Biodiesel and ASTM Diesel produced at bench-scale (utilizing RDO made from grease trap waste as an input) could not meet industry specifications utilizing the technologies that were selected by the investigators. Details of these investigations are discussed in this report and will hopefully provide a starting point for other researchers interested in these pathways in future studies. Although results were inconclusive in finding ways to utilize RDO technology, in effect, as a pretreatment for commonly discussed technologies such as Biodiesel and ASTM Diesel, this study does shed light on the properties, performance and cost of utilizing waste greases directly as a retail liquid fuel (RDO). The utilization as a retail RDO as a boiler fuel, or for other such applications, is the most important finding of the study.

  16. Prospective and development of butanol as an advanced biofuel.

    PubMed

    Xue, Chuang; Zhao, Xin-Qing; Liu, Chen-Guang; Chen, Li-Jie; Bai, Feng-Wu

    2013-12-01

    Butanol has been acknowledged as an advanced biofuel, but its production through acetone-butanol-ethanol (ABE) fermentation by clostridia is still not economically competitive, due to low butanol yield and titer. In this article, update progress in butanol production is reviewed. Low price and sustainable feedstocks such as lignocellulosic residues and dedicated energy crops are needed for butanol production at large scale to save feedstock cost, but processes are more complicated, compared to those established for ABE fermentation from sugar- and starch-based feedstocks. While rational designs targeting individual genes, enzymes or pathways are effective for improving butanol yield, global and systems strategies are more reasonable for engineering strains with stress tolerance controlled by multigenes. Compared to solvent-producing clostridia, engineering heterologous species such as Escherichia coli and Saccharomyces cerevisiae with butanol pathway might be a solution for eliminating the formation of major byproducts acetone and ethanol so that butanol yield can be improved significantly. Although batch fermentation has been practiced for butanol production in industry, continuous operation is more productive for large scale production of butanol as a biofuel, but a single chemostat bioreactor cannot achieve this goal for the biphasic ABE fermentation, and tanks-in-series systems should be optimized for alternative feedstocks and new strains. Moreover, energy saving is limited for the distillation system, even total solvents in the fermentation broth are increased significantly, since solvents are distilled to ~40% by the beer stripper, and more than 95% water is removed with the stillage without phase change, even with conventional distillation systems, needless to say that advanced chemical engineering technologies can distil solvents up to ~90% with the beer stripper, and the multistage pressure columns can well balance energy consumption for solvent fraction

  17. 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. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  18. Genomic Advances to Improve Biomass for Biofuels (Genomics and Bioenergy)

    SciTech Connect

    Rokhsar, Daniel

    2008-02-11

    Lawrence Berkeley National Lab bioscientist Daniel Rokhsar discusses genomic advances to improve biomass for biofuels. He presented his talk Feb. 11, 2008 in Berkeley, California as part of Berkeley Lab's community lecture series. Rokhsar works with the U.S. Department of Energy's Joint Genome Institute and Berkeley Lab's Genomics Division.

  19. Crop residues for advanced biofuels workshop: A synposis

    USDA-ARS?s Scientific Manuscript database

    Crop residues are being harvested for a variety of purposes including their use as livestock feed and to produce advanced biofuels. Crop residue harvesting, by definition, reduces the potential annual carbon input to the soil from aboveground biomass but does not affect input from plant roots. The m...

  20. 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.

  1. Biofuels

    NASA Image and Video Library

    What’s green, slimy and packed full of energy? Algae, of course! This biofuel is just one of the many renewable energies NASA studies. Biofuels could generate and store energy for long-term human...

  2. 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.

  3. Perspectives on engineering strategies for improving biofuel production from microalgae--a critical review.

    PubMed

    Ho, Shih-Hsin; Ye, Xiaoting; Hasunuma, Tomohisa; Chang, Jo-Shu; Kondo, Akihiko

    2014-12-01

    Although the potential for biofuel production from microalgae via photosynthesis has been intensively investigated, information on the selection of a suitable operation strategy for microalgae-based biofuel production is lacking. Many published reports describe competitive strains and optimal culture conditions for use in biofuel production; however, the major impediment to further improvements is the absence of effective engineering strategies for microalgae cultivation and biofuel production. This comprehensive review discusses recent advances in understanding the effects of major environmental stresses and the characteristics of various engineering operation strategies on the production of biofuels (mainly biodiesel and bioethanol) using microalgae. The performances of microalgae-based biofuel-producing systems under various environmental stresses (i.e., irradiance, temperature, pH, nitrogen depletion, and salinity) and cultivation strategies (i.e., fed-batch, semi-continuous, continuous, two-stage, and salinity-gradient) are compared. The reasons for variations in performance and the underlying theories of the various production strategies are also critically discussed. The aim of this review is to provide useful information to facilitate development of innovative and feasible operation technologies for effectively increasing the commercial viability of microalgae-based biofuel production.

  4. 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.

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

    PubMed

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

    2008-12-01

    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.

  6. 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.

  7. Protein engineering in designing tailored enzymes and microorganisms for biofuels production

    PubMed Central

    Wen, Fei; Nair, Nikhil U; Zhao, Huimin

    2009-01-01

    Summary Lignocellulosic biofuels represent a sustainable, renewable, and the only foreseeable alternative energy source to transportation fossil fuels. However, the recalcitrant nature of lignocellulose poses technical hurdles to an economically viable biorefinery. Low enzymatic hydrolysis efficiency and low productivity, yield, and titer of biofuels are among the top cost contributors. Protein engineering has been used to improve the performances of lignocellulose-degrading enzymes, as well as proteins involved in biofuel synthesis pathways. Unlike its great success seen in other industrial applications, protein engineering has achieved only modest results in improving the lignocellulose-to-biofuels efficiency. This review will discuss the unique challenges that protein engineering faces in the process of converting lignocellulose to biofuels and how they are addressed by recent advances in this field. PMID:19660930

  8. Protein engineering in designing tailored enzymes and microorganisms for biofuels production.

    PubMed

    Wen, Fei; Nair, Nikhil U; Zhao, Huimin

    2009-08-01

    Lignocellulosic biofuels represent a sustainable, renewable, and the only foreseeable alternative energy source to transportation fossil fuels. However, the recalcitrant nature of lignocellulose poses technical hurdles to an economically viable biorefinery. Low enzymatic hydrolysis efficiency and low productivity, yield, and titer of biofuels are among the top cost contributors. Protein engineering has been used to improve the performance of lignocellulose-degrading enzymes, as well as proteins involved in biofuel synthesis pathways. Unlike its great success seen in other industrial applications, protein engineering has achieved only modest results in improving the lignocellulose-to-biofuels efficiency. This review will discuss the unique challenges that protein engineering faces in the process of converting lignocellulose to biofuels and how they are addressed by recent advances in this field.

  9. Synthesis of three advanced biofuels from ionic liquid-pretreated switchgrass using engineered Escherichia coli

    PubMed Central

    Bokinsky, Gregory; Peralta-Yahya, Pamela P.; George, Anthe; Holmes, Bradley M.; Steen, Eric J.; Dietrich, Jeffrey; Soon Lee, Taek; Tullman-Ercek, Danielle; Voigt, Christopher A.; Simmons, Blake A.; Keasling, Jay D.

    2011-01-01

    One approach to reducing the costs of advanced biofuel production from cellulosic biomass is to engineer a single microorganism to both digest plant biomass and produce hydrocarbons that have the properties of petrochemical fuels. Such an organism would require pathways for hydrocarbon production and the capacity to secrete sufficient enzymes to efficiently hydrolyze cellulose and hemicellulose. To demonstrate how one might engineer and coordinate all of the necessary components for a biomass-degrading, hydrocarbon-producing microorganism, we engineered a microorganism naïve to both processes, Escherichia coli, to grow using both the cellulose and hemicellulose fractions of several types of plant biomass pretreated with ionic liquids. Our engineered strains express cellulase, xylanase, beta-glucosidase, and xylobiosidase enzymes under control of native E. coli promoters selected to optimize growth on model cellulosic and hemicellulosic substrates. Furthermore, our strains grow using either the cellulose or hemicellulose components of ionic liquid-pretreated biomass or on both components when combined as a coculture. Both cellulolytic and hemicellulolytic strains were further engineered with three biofuel synthesis pathways to demonstrate the production of fuel substitutes or precursors suitable for gasoline, diesel, and jet engines directly from ionic liquid-treated switchgrass without externally supplied hydrolase enzymes. This demonstration represents a major advance toward realizing a consolidated bioprocess. With improvements in both biofuel synthesis pathways and biomass digestion capabilities, our approach could provide an economical route to production of advanced biofuels. PMID:22123987

  10. Synthesis of three advanced biofuels from ionic liquid-pretreated switchgrass using engineered Escherichia coli.

    PubMed

    Bokinsky, Gregory; Peralta-Yahya, Pamela P; George, Anthe; Holmes, Bradley M; Steen, Eric J; Dietrich, Jeffrey; Lee, Taek Soon; Tullman-Ercek, Danielle; Voigt, Christopher A; Simmons, Blake A; Keasling, Jay D

    2011-12-13

    One approach to reducing the costs of advanced biofuel production from cellulosic biomass is to engineer a single microorganism to both digest plant biomass and produce hydrocarbons that have the properties of petrochemical fuels. Such an organism would require pathways for hydrocarbon production and the capacity to secrete sufficient enzymes to efficiently hydrolyze cellulose and hemicellulose. To demonstrate how one might engineer and coordinate all of the necessary components for a biomass-degrading, hydrocarbon-producing microorganism, we engineered a microorganism naïve to both processes, Escherichia coli, to grow using both the cellulose and hemicellulose fractions of several types of plant biomass pretreated with ionic liquids. Our engineered strains express cellulase, xylanase, beta-glucosidase, and xylobiosidase enzymes under control of native E. coli promoters selected to optimize growth on model cellulosic and hemicellulosic substrates. Furthermore, our strains grow using either the cellulose or hemicellulose components of ionic liquid-pretreated biomass or on both components when combined as a coculture. Both cellulolytic and hemicellulolytic strains were further engineered with three biofuel synthesis pathways to demonstrate the production of fuel substitutes or precursors suitable for gasoline, diesel, and jet engines directly from ionic liquid-treated switchgrass without externally supplied hydrolase enzymes. This demonstration represents a major advance toward realizing a consolidated bioprocess. With improvements in both biofuel synthesis pathways and biomass digestion capabilities, our approach could provide an economical route to production of advanced biofuels.

  11. 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.

  12. Rapid saccharification for production of cellulosic biofuels.

    PubMed

    Lee, Dae-Seok; Wi, Seung Gon; Lee, Soo Jung; Lee, Yoon-Gyo; Kim, Yeong-Suk; Bae, Hyeun-Jong

    2014-04-01

    The economical production of biofuels is hindered by the recalcitrance of lignocellulose to processing, causing high consumption of processing enzymes and impeding hydrolysis of pretreated lignocellulosic biomass. We determined the major rate-limiting factor in the hydrolysis of popping pre-treated rice straw (PPRS) by examining cellulase adsorption to lignin and cellulose, amorphogenesis of PPRS, and re-hydrolysis. Based on the results, equivalence between enzyme loading and the open structural area of cellulose was required to significantly increase productive adsorption of cellulase and to accelerate enzymatic saccharification of PPRS. Amorphogenesis of PPRS by phosphoric acid treatment to expand open structural area of the cellulose fibers resulted in twofold higher cellulase adsorption and increased the yield of the first re-hydrolysis step from 13% to 46%. The total yield from PPRS was increased to 84% after 3h. These results provide evidence that cellulose structure is one of major effects on the enzymatic hydrolysis.

  13. The Good, the Bad, and the Ugly: Comparing the Climate Mitigation Potential of Advanced Biofuels

    NASA Astrophysics Data System (ADS)

    Cassidy, E. S.

    2014-12-01

    The federal policy known as the Renewable Fuel Standard mandates that by 2022, 21 billion gallons of advanced biofuels will be used in the U.S. fuel supply. So far this policy has resulted in drastically increased production of corn ethanol and only a small amount of advanced fuels. While most corn ethanol plants are not required to achieve a reduction in greenhouse gas emissions (when compared to gasoline), advanced biofuels are required to reduce emissions by 50 or 60 percent. But not all fuels that qualify for advanced status according to the Environmental Protection Agency have the same climate mitigation potential. This study ranks advanced fuel pathways approved by the EPA from good, to bad…to worse. Climate mitigation potential of these fuels is compared to previous research and examined using the EPA's modeling framework.

  14. 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

  15. 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.

  16. 75 FR 50986 - Notice of Contract Proposal (NOCP) for Payments to Eligible Advanced Biofuel Producers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ... Biofuel Producers AGENCY: Rural Business-Cooperative Service, USDA. ACTION: Notice to accept applications from previously excluded advanced biofuel producers and to modify the award methodology for remaining... funds under the Advanced Biofuel Payment Program. The March 12, 2010 Notice of Contract Proposal...

  17. 76 FR 13345 - Notice of Contract Proposal (NOCP) for Payments to Eligible Advanced Biofuel Producers

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-11

    ... Payments to Eligible Advanced Biofuel Producers AGENCY: Rural Business-Cooperative Service and Rural... enter into Contracts to make payments to eligible advanced biofuel producers under the Bioenergy Program... starch, in a biofuel facility located in a State. The Notice announces the availability of up to...

  18. Improving Butanol Fermentation To Enter the Advanced Biofuel Market

    PubMed Central

    Tracy, Bryan P.

    2012-01-01

    ABSTRACT 1-Butanol is a large-volume, intermediate chemical with favorable physical and chemical properties for blending with or directly substituting for gasoline. The per-volume value of butanol, as a chemical, is sufficient for investing into the recommercialization of the classical acetone-butanol-ethanol (ABE) (E. M. Green, Curr. Opin. Biotechnol. 22:337–343, 2011) fermentation process. Furthermore, with modest improvements in three areas of the ABE process, operating costs can be sufficiently decreased to make butanol an economically viable advanced biofuel. The three areas of greatest interest are (i) maximizing yields of butanol on any particular substrate, (ii) expanding substrate utilization capabilities of the host microorganism, and (iii) reducing the energy consumption of the overall production process, in particular the separation and purification operations. In their study in the September/October 2012 issue of mBio, Jang et al. [mBio 3(5):e00314-12, 2012] describe a comprehensive study on driving glucose metabolism in Clostridium acetobutylicum to the production of butanol. Moreover, they execute a metabolic engineering strategy to achieve the highest yet reported yields of butanol on glucose. PMID:23232720

  19. Sweet sorghum as biofuel feedstock: recent advances and available resources.

    PubMed

    Mathur, Supriya; Umakanth, A V; Tonapi, V A; Sharma, Rita; Sharma, Manoj K

    2017-01-01

    Sweet sorghum is a promising target for biofuel production. It is a C4 crop with low input requirements and accumulates high levels of sugars in its stalks. However, large-scale planting on marginal lands would require improved varieties with optimized biofuel-related traits and tolerance to biotic and abiotic stresses. Considering this, many studies have been carried out to generate genetic and genomic resources for sweet sorghum. In this review, we discuss various attributes of sweet sorghum that make it an ideal candidate for biofuel feedstock, and provide an overview of genetic diversity, tools, and resources available for engineering and/or marker-assisting breeding of sweet sorghum. Finally, the progress made so far, in identification of genes/quantitative trait loci (QTLs) important for agronomic traits and ongoing molecular breeding efforts to generate improved varieties, has been discussed.

  20. An integrated approach: advances in the use of Clostridium for biofuel.

    PubMed

    Kök, M Samil

    2015-01-01

    Almost 90% of our energy comes from fossil fuels, which are both limited and polluting, hence the need to find alternative sources. Biofuels can provide a sustainable and renewable source of energy for the future. Recent significant advances in genetic engineering and fermentation technology have made microbial bio-based production of chemicals from renewable resources more viable. Clostridium species are considered as promising micro-organisms for the production of a wide range of chemicals for industrial use. However, a number of scientific challenges still need to be overcome to facilitate an economically viable production system. These include the use of cheap non-food-based substrates, a better understanding of the metabolic processes involved, improvement of strains through genetic engineering and innovation in process technology. This paper reviews recent developments in these areas, advancing the use of Clostridium within an industrial context especially for the production of biofuels.

  1. 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

  2. The South's outlook for sustainable forest bioenergy and biofuels production

    Treesearch

    David Wear; Robert Abt; Janaki Alavalapati; Greg Comatas; Mike Countess; Will McDow

    2010-01-01

    The future of a wood-based biofuel/bioenergy sector could hold important implications for the use, structure and function of forested landscapes in the South. This paper examines a set of questions regarding the potential effects of biofuel developments both on markets for traditional timber products and on the provision of various non-timber ecosystem services. In...

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

    PubMed

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

    2016-01-01

    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.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  5. Potential of Arabidopsis systems biology to advance the biofuel field.

    PubMed

    Vanholme, Ruben; Van Acker, Rebecca; Boerjan, Wout

    2010-11-01

    Plant biomass is a renewable and potentially sustainable resource for the production of liquid biofuels and a multitude of bio-based materials. To tailor plants for biofuel production, a powerful gene discovery program targeted to cell wall recalcitrance genes is needed. In parallel, a system is required that reveals the pleiotropic effects of gene modifications and that delivers the fundamental knowledge necessary for successful gene stacking. In our opinion, these objectives can be pioneered through a systems biology approach in Arabidopsis. We develop our ideas with a focus on the lignin biosynthetic pathway, because lignin is among the most important factors determining cell wall recalcitrance. Copyright © 2010 Elsevier Ltd. All rights reserved.

  6. Biofuel Crops Expansion: Evaluating the Impact on the Agricultural Water Scarcity Costs and Hydropower Production with Hydro Economic Modeling

    NASA Astrophysics Data System (ADS)

    Marques, G.

    2015-12-01

    Biofuels such as ethanol from sugar cane remain an important element to help mitigate the impacts of fossil fuels on the atmosphere. However, meeting fuel demands with biofuels requires technological advancement for water productivity and scale of production. This may translate into increased water demands for biofuel crops and potential for conflicts with incumbent crops and other water uses including domestic, hydropower generation and environmental. It is therefore important to evaluate the effects of increased biofuel production on the verge of water scarcity costs and hydropower production. The present research applies a hydro-economic optimization model to compare different scenarios of irrigated biofuel and hydropower production, and estimates the potential tradeoffs. A case study from the Araguari watershed in Brazil is provided. These results should be useful to (i) identify improved water allocation among competing economic demands, (ii) support water management and operations decisions in watersheds where biofuels are expected to increase, and (iii) identify the impact of bio fuel production in the water availability and economic value. Under optimized conditions, adoption of sugar cane for biofuel production heavily relies on the opportunity costs of other crops and hydropower generation. Areas with a lower value crop groups seem more suitable to adopt sugar cane for biofuel when the price of ethanol is sufficiently high and the opportunity costs of hydropower productions are not conflicting. The approach also highlights the potential for insights in water management from studying regional versus larger scales bundled systems involving water use, food production and power generation.

  7. Renewable Enhanced Feedstocks for Advanced Biofuels and Bioproducts (REFABB)

    SciTech Connect

    Peoples, Oliver; Snell, Kristi

    2016-06-09

    % yield, demonstrated the need to consider up-front the limitations of trying to adopt existing equipment to a task for which subsequent basic research studies indicated it was not suitable. New information was developed in the most complex of the chemical conversions studied, advanced catalysis to make acrylic acid, a chemical used widely to make paints, and this was published in a scientific journal. In regard to the technical effectiveness, the crop science aspects were for the most part remarkably effective in addressing the underlying objectives indicating the soundness of the technical approach. With time, it should be possible to fully develop the advanced biomass biorefinery feedstock. Challenges within the thermolysis step to recover crotonic acid meant that by the end of the project we were not able to demonstrate an economic case based on data from scaled up equipment. Solving this will take further research and development work. As a general statement, the broadest public good is in demonstrating the value of funding a very unique approach to the complex problem of enabling large-scale biomass biorefineries which resulted in significant progress towards the ultimate goal and a clearer understanding of the technical hurdles remaining. Perhaps not surprisingly, some of the broader benefits to the public come from the use of the REFABB project innovations in areas unrelated to the initial objective. It is worth highlighting the breakthrough developments in identifying three single global regulator genes which can be engineered into plants to dramatically increase photosynthesis and carbon capturing ability. These genes have tremendous potential for use in major food crops, in particular corn to enhance grain yield and based on recent findings, increase the root density, a critical key to increasing carbon sequestration in agriculture and improving the sustainability of global food and biofuel production.

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

    SciTech Connect

    Sastri, B.; Lee, A.

    2008-09-15

    . 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.

  9. 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.

  10. 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.

  11. Regional water footprints of potential biofuel production in China.

    PubMed

    Xie, Xiaomin; Zhang, Tingting; Wang, Liming; Huang, Zhen

    2017-01-01

    Development of biofuels is considered as one of the important ways to replace conventional fossil energy and mitigate climate change. However, rapid increase of biofuel production could cause other environmental concerns in China such as water stress. This study is intended to evaluate the life-cycle water footprints (WF) of biofuels derived from several potential non-edible feedstocks including cassava, sweet sorghum, and Jatropha curcas in China. Different water footprint types including blue water, green water, and grey water are considered in this study. Based on the estimated WF, water deprivation impact and water stress degree on local water environment are further analyzed for different regions in China. On the basis of the feedstock resource availability, sweet sorghum, cassava, and Jatropha curcas seeds are considered as the likely feedstocks for biofuel production in China. The water footprint results show that the feedstock growth is the most water footprint intensive process, while the biofuel conversion and transportation contribute little to total water footprints. Water footprints vary significantly by region with climate and soil variations. The life-cycle water footprints of cassava ethanol, sweet sorghum ethanol, and Jatropha curcas seeds biodiesel were estimated to be 73.9-222.2, 115.9-210.4, and 64.7-182.3 L of water per MJ of biofuel, respectively. Grey water footprint dominates the life-cycle water footprint for each type of the biofuels. Development of biofuels without careful water resource management will exert significant impacts on local water resources. The water resource impacts vary significantly among regions. For example, based on blue and grey water consumption, Gansu province in China will suffer much higher water stress than other regions do due to limited available water resources and large amount of fertilizer use in that province. In term of blue water, Shandong province is shown with the most severe water stress issue

  12. Engineering of plant cell walls for enhanced biofuel production.

    PubMed

    Loqué, Dominique; Scheller, Henrik V; Pauly, Markus

    2015-06-01

    The biomass of plants consists predominately of cell walls, a sophisticated composite material composed of various polymer networks including numerous polysaccharides and the polyphenol lignin. In order to utilize this renewable, highly abundant resource for the production of commodity chemicals such as biofuels, major hurdles have to be surpassed to reach economical viability. Recently, major advances in the basic understanding of the synthesis of the various wall polymers and its regulation has enabled strategies to alter the qualitative composition of wall materials. Such emerging strategies include a reduction/alteration of the lignin network to enhance polysaccharide accessibility, reduction of polymer derived processing inhibitors, and increases in polysaccharides with a high hexose/pentose ratio.

  13. Metabolic engineering of biosynthetic pathway for production of renewable biofuels.

    PubMed

    Singh, Vijai; Mani, Indra; Chaudhary, Dharmendra Kumar; Dhar, Pawan Kumar

    2014-02-01

    Metabolic engineering is an important area of research that involves editing genetic networks to overproduce a certain substance by the cells. Using a combination of genetic, metabolic, and modeling methods, useful substances have been synthesized in the past at industrial scale and in a cost-effective manner. Currently, metabolic engineering is being used to produce sufficient, economical, and eco-friendly biofuels. In the recent past, a number of efforts have been made towards engineering biosynthetic pathways for large scale and efficient production of biofuels from biomass. Given the adoption of metabolic engineering approaches by the biofuel industry, this paper reviews various approaches towards the production and enhancement of renewable biofuels such as ethanol, butanol, isopropanol, hydrogen, and biodiesel. We have also identified specific areas where more work needs to be done in the future.

  14. Environmental effect of constructed wetland as biofuel production system

    NASA Astrophysics Data System (ADS)

    Liu, Dong

    2017-04-01

    Being as a renewable energy, biofuel has attracted worldwide attention. Clean biofuel production is an effective way to mitigate global climate change and energy crisis. Biofuel may offer a promising alternative to fossil fuels, but serious concerns arise about the adverse greenhouse gas consequences from using nitrogen fertilizers. Waste-nitrogen recycling is an attractive idea. Here we advocate a win-win approach to biofuel production which takes advantage of excessive nitrogen in domestic wastewater treated via constructed wetland (CW) in China. This study will carry on environmental effect analysis of CW as a biomass generation system through field surveys and controllable simulated experiments. This study intends to evaluate net energy balance, net greenhouse effect potential and ecosystem service of CW as biomass generation system, and make comparation with traditional wastewater treatment plant and other biofuel production systems. This study can provide a innovation mode in order to solve the dilemma between energy crops competed crops on production land and excessive nitrogen fertilizer of our traditional energy plant production. Data both from our experimental CWs in China and other researches on comparable CWs worldwide showed that the biomass energy yield of CWs can reach 182.3 GJ ha-1 yr-1, which was two to eight times higher than current biofuel-production systems. Energy output from CW was ˜137% greater than energy input for biofuel production. If CWs are designed with specific goal of biofuel production, biofuel production can be greatly enhanced through the optimization of N supply, hydraulic structures, and species selection in CWs. Assuming that 2.0 Tg (1 Tg = 1012 g) waste nitrogen contained in domestic wastewater is treated by CWs, biofuel production can account for 1.2% of national gasoline consumption in China. The proportion would increase to 6.7% if extra nitrogen (9.5 Tg) from industrial wastewater and agricultural runoff was included

  15. Biofuel Production: Considerations for USACE Civil Works Business Lines

    DTIC Science & Technology

    2014-12-01

    Agricultural Management Influence on Long-Term Soil Organic Carbon Dynamics: Implications for Biofuel Production.” Agronomy Journal 103(1): 234–246. ERDC...impact, namely in terms of soil resources, water quality and water use, biodiversity, and ecosystem services (Gollany et al. 2011). It is important to...analyze biomass feedstocks, biopower, and biofuels data from the U.S. Department of Energy (DoE), U.S. EPA, and the U.S. Department of Agriculture

  16. 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.

  17. Optimization of Biofuel Production from Transgenic Microalgae

    DTIC Science & Technology

    2008-05-31

    determine empirically the best LHC content for optimal growth at high light intensities. Non-destructive oil extraction : Harvesting algae and... extracting oil accounts for 50% of the cost of producing algal biofuels. Much of this cost is associated with concentrating algae from 0.1% of the mass...during the extraction process so a new culure must be grown each time the algae are harvested. A more efficient oil extraction technology would

  18. 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.

  19. Advanced Biorefineries for Production of Fuel Ethanol

    USDA-ARS?s Scientific Manuscript database

    This review, "Advanced biorefineries for production of fuel ethanol," is a chapter in the Wiley book entitled Biomass to Biofuels: Strategies for Global Industries and is intended to cover all major ethanol production processes to date. The chapter discusses current fuel ethanol production processe...

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

    DOEpatents

    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.

  1. 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.

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

    DOEpatents

    Wohlbach, Dana J.; Gasch, Audrey P.

    2016-11-29

    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.

  3. [Advanced biofuel-oriented engineering of fatty acid pathway: a review].

    PubMed

    Zhou, Yongjin J; Zhao, Zongbao K

    2011-09-01

    Biofuel is in high demand as an alternative energy source for petroleum and diesel. Fatty acid-based biofuel has higher energy density and better compatibility with existing infrastructures. Microbial fatty acid biosynthetic pathway is important to develop biofuel. In this article, recent progresses on the modification and reconstruction of fatty acid metabolism for the production of biofuel were reviewed, with a focus on micro-diesel, long chain fatty alcohol and alkane. Problems, solutions and directions for further development of fatty acid-based biofuel were also discussed in the respect of synthetic biology.

  4. Enhancing microbial production of biofuels by expanding microbial metabolic pathways.

    PubMed

    Yu, Ping; Chen, Xingge; Li, Peng

    2016-08-10

    Fatty acid, isoprenoid, and alcohol pathways have been successfully engineered to produce biofuels. By introducing three genes, atfA, adhE, and pdc, into Escherichia coli to expand fatty acid pathway, up to 1.28 g/L of fatty acid ethyl esters can be achieved. The isoprenoid pathway can be expanded to produce bisabolene with a high titer of 900 mg/L in Saccharomyces cerevisiae. Short- and long-chain alcohols can also be effectively biosynthesized by extending the carbon chain of ketoacids with an engineered "+1" alcohol pathway. Thus, it can be concluded that expanding microbial metabolic pathways has enormous potential for enhancing microbial production of biofuels for future industrial applications. However, some major challenges for microbial production of biofuels should be overcome to compete with traditional fossil fuels: lowering production costs, reducing the time required to construct genetic elements and to increase their predictability and reliability, and creating reusable parts with useful and predictable behavior. To address these challenges, several aspects should be further considered in future: mining and transformation of genetic elements related to metabolic pathways, assembling biofuel elements and coordinating their functions, enhancing the tolerance of host cells to biofuels, and creating modular subpathways that can be easily interconnected. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  5. Utilization of biofuel production residuals for food applications

    USDA-ARS?s Scientific Manuscript database

    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 ...

  6. 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…

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

    USDA-ARS?s Scientific Manuscript database

    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. Value Added Products from Renewable Biofuels

    SciTech Connect

    Blum, Paul

    2014-07-31

    Cellulosic ethanol is an emerging biofuel that will make strong contributions to American domestic energy needs. In the US midwest the standard method for pretreatment of biomass uses hot acid to deconstruct lignocellulose. While other methods work, they are not in common use. Therefore it is necessary to work within this context to achieve process improvements and reductions in biofuel cost. Technology underlying this process could supplement and even replace commodity enzymes with engineered microbes to convert biomass-derived lignocellulose feedstocks into biofuels and valueadded chemicals. The approach that was used here was based on consolidated bioprocessing. Thermoacidophilic microbes belonging to the Domain Archaea were evaluated and modfied to promote deconvolution and saccharification of lignocellulose. Biomass pretreatment (hot acid) was combined with fermentation using an extremely thermoacidophilic microbial platform. The identity and fate of released sugars was controlled using metabolic blocks combined with added biochemical traits where needed. LC/MS analysis supported through the newly established Nebraska Bioenergy Facility provided general support for bioenergy researchers at the University of Nebraska. The primary project strategy was to use microbes that naturally flourish in hot acid (thermoacidophiles) with conventional biomass pretreatment that uses hot acid. The specific objectives were: to screen thermoacidophilic taxa for the ability to deconvolute lignocellulose and depolymerize associated carbohydrates; evaluate and respond to formation of “inhibitors” that arose during incubation of lignocellulose under heated acidic conditions; identify and engineer “sugar flux channeling and catabolic blocks” that redirect metabolic pathways to maximize sugar concentrations; expand the hydrolytic capacity of extremely thermoacidophilic microbes through the addition of deconvolution traits; and establish the Nebraska Bioenergy Facility (NBF

  10. 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.

  11. 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.

  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.

  14. Review of the cultivation program within the National Alliance for Advanced Biofuels and Bioproducts

    DOE PAGES

    Lammers, Peter J.; Huesemann, Michael; Boeing, Wiebke; ...

    2016-12-12

    The cultivation efforts within the National Alliance for Advanced Biofuels and Bioproducts (NAABB) were developed to provide four major goals for the consortium, which included biomass production for downstream experimentation, development of new assessment tools for cultivation, development of new cultivation reactor technologies, and development of methods for robust cultivation. The NAABB consortium testbeds produced over 1500 kg of biomass for downstream processing. The biomass production included a number of model production strains, but also took into production some of the more promising strains found through the prospecting efforts of the consortium. Cultivation efforts at large scale are intensive andmore » costly, therefore the consortium developed tools and models to assess the productivity of strains under various environmental conditions, at lab scale, and validated these against scaled outdoor production systems. Two new pond-based bioreactor designs were tested for their ability to minimize energy consumption while maintaining, and even exceeding, the productivity of algae cultivation compared to traditional systems. Also, molecular markers were developed for quality control and to facilitate detection of bacterial communities associated with cultivated algal species, including the Chlorella spp. pathogen, Vampirovibrio chlorellavorus, which was identified in at least two test site locations in Arizona and New Mexico. Finally, the consortium worked on understanding methods to utilize compromised municipal wastewater streams for cultivation. In conclusion, this review provides an overview of the cultivation methods and tools developed by the NAABB consortium to produce algae biomass, in robust low energy systems, for biofuel production.« less

  15. Review of the cultivation program within the National Alliance for Advanced Biofuels and Bioproducts

    SciTech Connect

    Lammers, Peter J.; Huesemann, Michael; Boeing, Wiebke; Anderson, Daniel B.; Arnold, Robert G.; Bai, Xuemei; Bhole, Manish; Brhanavan, Yalini; Brown, Louis; Brown, Jola; Brown, Judith K.; Chisholm, Stephen; Meghan Downes, C.; Fulbright, Scott; Ge, Yufeng; Holladay, Jonathan E.; Ketheesan, Balachandran; Khopkar, Avinash; Koushik, Ambica; Laur, Paul; Marrone, Babetta L.; Mott, John B.; Nirmalakhandan, Nagamany; Ogden, Kimberly L.; Parsons, Ronald L.; Polle, Juergen; Ryan, Randy D.; Samocha, Tzachi; Sayre, Richard T.; Seger, Mark; Selvaratnam, Thinesh; Sui, Ruixiu; Thomasson, Alex; Unc, Adrian; Van Voorhies, Wayne; Waller, Peter; Yao, Yao; Olivares, José A.

    2016-12-12

    The cultivation efforts within the National Alliance for Advanced Biofuels and Bioproducts (NAABB) were developed to provide four major goals for the consortium, which included biomass production for downstream experimentation, development of new assessment tools for cultivation, development of new cultivation reactor technologies, and development of methods for robust cultivation. The NAABB consortium testbeds produced over 1500 kg of biomass for downstream processing. The biomass production included a number of model production strains, but also took into production some of the more promising strains found through the prospecting efforts of the consortium. Cultivation efforts at large scale are intensive and costly, therefore the consortium developed tools and models to assess the productivity of strains under various environmental conditions, at lab scale, and validated these against scaled outdoor production systems. Two new pond-based bioreactor designs were tested for their ability to minimize energy consumption while maintaining, and even exceeding, the productivity of algae cultivation compared to traditional systems. Also, molecular markers were developed for quality control and to facilitate detection of bacterial communities associated with cultivated algal species, including the Chlorella spp. pathogen, Vampirovibrio chlorellavorus, which was identified in at least two test site locations in Arizona and New Mexico. Finally, the consortium worked on understanding methods to utilize compromised municipal wastewater streams for cultivation. In conclusion, this review provides an overview of the cultivation methods and tools developed by the NAABB consortium to produce algae biomass, in robust low energy systems, for biofuel production.

  16. Genetically engineered crops for biofuel production: regulatory perspectives.

    PubMed

    Lee, David; Chen, Alice; Nair, Ramesh

    2008-01-01

    There are numerous challenges in realizing the potential of biofuels that many policy makers have envisioned. The technical challenges in making the production of biofuels economical and on a scale to replace a significant fraction of transportation fuel have been well described, along with the potential environmental concerns. The use of biotechnology can potentially address many of these technical challenges and environmental concerns, but brings significant regulatory hurdles that have not been discussed extensively in the scientific community. This review will give an overview of the approaches being developed to produce transgenic biofuel feedstocks, particularly cellulosic ethanol, and the regulatory process in the United States that oversees the development and commercialization of new transgenic plants. We hope to illustrate that the level of regulation for transgenic organisms is not proportional to their potential risk to human health or the environment, and that revisions to the regulatory system in the U.S. currently under consideration are necessary to streamline the process.

  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. 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...

  19. Small scale production of biofuels: a feasibility assessment

    SciTech Connect

    Geyler, J.

    1980-01-01

    Current public policy fails to adequately address one of the most exigent concerns of the agricultural producer: the cost and availability of energy. Specifically, they are interested in energy production alternatives that are feasible and economic for implementation by smaller agricultural producers. After a extended review of much of the available popular and technical literature, as well as conducting interviews with numerous individuals knowledgeable in the field of alternative energy production, the Roosevelt-Custer Regional Council for Development has prepared this preliminary feasibility assessment on the small scale production of biofuels in North Dakota. The production of energy from renewable sources is not chimerical; it is reality. Currently, North Dakotan's rely on energy produced from agricultural products to run their automobiles and to heat their homes, as well as to dry the crops on which much of the North Dakota economy depends. Over the next 20 years, this reliance on renewable energy sources is expected to triple. Unfortunately, most of the processes currently used to produce these biofuels are not adaptable for use by the smaller producer/consumer. Today, economics simply preclude the small scale production of biofuels. A deplorable consequence of this lag between demand and technical feasibility is the appearance of the quick-buck consultant. These individuals have not limited their activities to North Dakota but, in fact, they have appeared over the length and breadth of this Nation. This report then is an assessment of the feasibility of producing biofuels in North Dakota by the small scale producer. Specific types of biofuels to be critiqued are: alcohol; vegetable oils; biogas/methane; and biomass briquettes.

  20. Small scale production of biofuels: a feasibility assessment

    SciTech Connect

    Geyler, J.

    1980-01-01

    Current public policy fails to adequately address one of the most exigent concerns of the agricultural producer: the cost and availability of energy. Specifically, they are interested in energy production alternatives that are feasible and economic for implementation by smaller agricultural producers. After an extended review of much of the available popular and technical literature, as well as conducting interviews with numerous individuals knowledgeable in the field of alternative energy production, the Roosevelt-Custer Regional Council for Development has prepared this preliminary feasibility assessment on the small scale production of biofuels in North Dakota. The production of energy from renewable sources is not commerical; it is reality. Currently, North Dakotan's rely on energy produced from agricultural products to run their automobiles and to heat their homes, as well as to dry the crops on which much of the North Dakota economy depends. Over the next 20 years, this reliance on renewable energy sources is expected to triple. Unfortunately, most of the processes currently used to produce these biofuels are not adaptable for use by the smaller producer/consumer. Today, economics simply preclude the small scale production of biofuels. A deplorable consequence of this lag between demand and technical feasibility is the appearance of the quick-buck consultant. These individuals have not limited their activities to North Dakota but, in fact, they have appeared over the length and breadth of this nation. This report then is an assessment of the feasibility of producing biofuels in North Dakota by the small scale producer. Specific types of biofuels to be critiqued are: alcohol; vegetable oils; biogas/methane; and biomass briquettes.

  1. Wastewater treatment high rate algal ponds for biofuel production.

    PubMed

    Park, J B K; Craggs, R J; Shilton, A N

    2011-01-01

    While research and development of algal biofuels are currently receiving much interest and funding, they are still not commercially viable at today's fossil fuel prices. However, a niche opportunity may exist where algae are grown as a by-product of high rate algal ponds (HRAPs) operated for wastewater treatment. In addition to significantly better economics, algal biofuel production from wastewater treatment HRAPs has a much smaller environmental footprint compared to commercial algal production HRAPs which consume freshwater and fertilisers. In this paper the critical parameters that limit algal cultivation, production and harvest are reviewed and practical options that may enhance the net harvestable algal production from wastewater treatment HRAPs including CO(2) addition, species control, control of grazers and parasites and bioflocculation are discussed.

  2. 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

  3. Trade-offs between Biofuels Energy Production, Land Use and Water Use in Florida

    SciTech Connect

    Fidler, Michal; Capece, John; Hanlon, Edward; Alsharif, Kamal

    2014-02-11

    Objective of the presentation is to document land use and water use implications of biomass production to demonstrate the overall resources implications associated with bioethanol production for Florida’s transportation sector needs. Rationale for using biofuels (BF) is explained, so are advantages & challenges of BF production and use. Land use changes (LUC) in Florida are presented and consequences outlined. It is documented that Florida’s agricultural land is a very limited resource, with only 0.43 ac/person comparing to the global average of 1.71 ac/person. The direct relation of increased biofuels production causing increased water use is explained. Favorable climate, water resources, advanced research, traditional leading agricultural role, minor oil reserves, no refineries and increasing energy demands are the main reasons why Florida considers pursuing BF production in large scale. Eight various bioethanol crops produced in Florida were considered in this study (Miscanthus, Switchgrass, Sweet Sorghum, Corn, Elephantgrass, Sugarcane, Energycane, Eucalyptus). Biomass yield and bioethanol yield of these crops are documented. Bioethanol needs of Florida are estimated and related land requirements for the needed bioethanol production calculated. Projections for various bioethanol blends (E15 to E85) are then presented. Finally, water demand for biofuels production is quantified. It is concluded that land use requirement for production of all ethanol in E85 fuel blend in Florida is roughly the same as the total available ag land in Florida for the best yielding biofuels crops (energycane, eucalyptus). Water demand for production of all ethanol needed for E100 would increase current overall water consumption in Florida between 65% and 100% for the most common biofuels crops. Vehicular energy is only 33% of Floridians energy consumption, so even all Florida’s agricultural land was given up for biofuels, it would still produce only 33% of Florida’s total

  4. 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.

  5. 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

  6. Microalgal cultivation with biogas slurry for biofuel production.

    PubMed

    Zhu, Liandong; Yan, Cheng; Li, Zhaohua

    2016-11-01

    Microalgal growth requires a substantial amount of chemical fertilizers. An alternative to the utilization of fertilizer is to apply biogas slurry produced through anaerobic digestion to cultivate microalgae for the production of biofuels. Plenty of studies have suggested that anaerobic digestate containing high nutrient contents is a potentially feasible nutrient source to culture microalgae. However, current literature indicates a lack of review available regarding microalgal cultivation with biogas slurry for the production of biofuels. To help fill this gap, this review highlights the integration of digestate nutrient management with microalgal production. It first unveils the current status of microalgal production, providing basic background to the topic. Subsequently, microalgal cultivation technologies using biogas slurry are discussed in detail. A scale-up scheme for simultaneous biogas upgrade and digestate application through microalgal cultivation is then proposed. Afterwards, several uncertainties that might affect this practice are explored. Finally, concluding remarks are put forward. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. 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.

  8. 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

  9. 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.

  10. Dynamic Modeling of Learning in Emerging Energy Industries: The Example of Advanced Biofuels in the United States

    SciTech Connect

    Vimmerstedt, Laura; Peterson, Steve; Bush, Brian

    2016-05-01

    This paper (and its supplemental model) presents novel approaches to modeling interactions and related policies among investment, production, and learning in an emerging competitive industry. New biomass-to-biofuels pathways are being developed and commercialized to support goals for U.S. advanced biofuel use, such as those in the Energy Independence and Security Act of 2007. We explore the impact of learning rates and techno-economics in a learning model excerpted from the Biomass Scenario Model (BSM), developed by the U.S. Department of Energy and the National Renewable Energy Laboratory to explore the impact of biofuel policy on the evolution of the biofuels industry. The BSM integrates investment, production, and learning among competing biofuel conversion options that are at different stages of industrial development. We explain the novel methods used to simulate the impact of differing assumptions about mature industry techno-economics and about learning rates while accounting for the different maturity levels of various conversion pathways. A sensitivity study shows that the parameters studied (fixed capital investment, process yield, progress ratios, and pre-commercial investment) exhibit highly interactive effects, and the system, as modeled, tends toward market dominance of a single pathway due to competition and learning dynamics.

  11. Dynamic Modeling of Learning in Emerging Energy Industries: The Example of Advanced Biofuels in the United States: Preprint

    SciTech Connect

    Vimmerstedt, Laura J.; Bush, Brian W.; Peterson, Steven O.

    2015-09-03

    This paper (and its supplemental model) presents novel approaches to modeling interactions and related policies among investment, production, and learning in an emerging competitive industry. New biomass-to-biofuels pathways are being developed and commercialized to support goals for U.S. advanced biofuel use, such as those in the Energy Independence and Security Act of 2007. We explore the impact of learning rates and techno-economics in a learning model excerpted from the Biomass Scenario Model (BSM), developed by the U.S. Department of Energy and the National Renewable Energy Laboratory to explore the impact of biofuel policy on the evolution of the biofuels industry. The BSM integrates investment, production, and learning among competing biofuel conversion options that are at different stages of industrial development. We explain the novel methods used to simulate the impact of differing assumptions about mature industry techno-economics and about learning rates while accounting for the different maturity levels of various conversion pathways. A sensitivity study shows that the parameters studied (fixed capital investment, process yield, progress ratios, and pre-commercial investment) exhibit highly interactive effects, and the system, as modeled, tends toward market dominance of a single pathway due to competition and learning dynamics.

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

    DOEpatents

    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.

  13. 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.

  14. 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

  15. 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.

  16. Energy return on investment for algal biofuel production coupled with wastewater treatment.

    PubMed

    Beal, Colin M; Stillwell, Ashlynn S; King, Carey W; Cohen, Stuart M; Berberoglu, Halil; Bhattarai, Rajendra P; Connelly, Rhykka L; Webber, Michael E; Hebner, Robert E

    2012-09-01

    This study presents a second-order energy return on investment analysis to evaluate the mutual benefits of combining an advanced wastewater treatment plant (WWTP) (with biological nutrient removal) with algal biofuel production. With conventional, independently operated systems, algae production requires significant material inputs, which require energy directly and indirectly, and the WWTP requires significant energy inputs for treatment of the waste streams. The second-order energy return on investment values for independent operation of the WWTP and the algal biofuels production facility were determined to be 0.37 and 0.42, respectively. By combining the two, energy inputs can be reduced significantly. Consequently, the integrated system can outperform the isolated system, yielding a second-order energy return on investment of 1.44. Combining these systems transforms two energy sinks to a collective (second-order) energy source. However, these results do not include capital, labor, and other required expenses, suggesting that profitable deployment will be challenging.

  17. Alternative biofuel production in non-natural hosts.

    PubMed

    McEwen, Jordan T; Atsumi, Shota

    2012-10-01

    Global energy and environmental concerns have stimulated increased efforts in synthesizing petroleum-derived products from renewable resources. Biological production of metabolites for fuel is increasingly becoming a feasible, renewable, environmentally sound alternative. However, many of these chemicals are not highly produced in any known native organism. Here we review the current progress of modifying microorganisms with heterogeneous elements for the production of biofuels. This strategy has been extensively employed in a variety of hosts for the development of production of various alcohols, fatty acids, alkenes and alkanes.

  18. The Navy Biofuel Initiative Under the Defense Production Act

    DTIC Science & Technology

    2012-06-22

    Market for Biomass -Based Diesel Fuel in the Renewable Fuel Standard (RFS), by Brent D. Yacobucci, The Market for Biomass -Based Diesel Fuel in the...defense.17 During the 1970s, DOE directed a synthetic fuels program toward commercializing coal liquefaction, coal gasification , and oil shale... Biomass : Background and Policy, by Anthony Andrews and Jeffrey Logan. The Navy Biofuel Initiative Under the Defense Production Act Congressional

  19. Developments and perspectives of photobioreactors for biofuel production.

    PubMed

    Morweiser, Michael; Kruse, Olaf; Hankamer, Ben; Posten, Clemens

    2010-07-01

    The production of biofuels from microalgae requires efficient photobioreactors in order to meet the tight constraints of energy efficiency and economic profitability. Current cultivation systems are designed for high-value products rather than for mass production of cheap energy carriers. Future bioreactors will imply innovative solutions in terms of energy efficiency, light and gas transfer or attainable biomass concentration to lower the energy demand and cut down production costs. A new generation of highly developed reactor designs demonstrates the enormous potential of photobioreactors. However, a net energy production with microalgae remains challenging. Therefore, it is essential to review all aspects and production steps for optimization potential. This includes a custom process design according to production organism, desired product and production site. Moreover, the potential of microalgae to synthesize valuable products additionally to the energetic use can be integrated into a production concept as well as waste streams for carbon supply or temperature control.

  20. Assessing extension and outreach education levels for biofuel feedstock production in the Western United States

    USDA-ARS?s Scientific Manuscript database

    A growing biofuels industry requires the development of effective methods to educate farmers, government, and agribusiness about biofuel feedstock production if the market is going to significantly expand beyond first generation biofuels. Extension and outreach education provides a conduit for impor...

  1. Review of the algal biology program within the National Alliance for Advanced Biofuels and Bioproducts

    SciTech Connect

    Unkefer, Clifford Jay; Sayre, Richard Thomas; Magnuson, Jon K.; Anderson, Daniel B.; Baxter, Ivan; Blaby, Ian K.; Brown, Judith K.; Carleton, Michael; Cattolico, Rose Ann; Dale, Taraka T.; Devarenne, Timothy P.; Downes, C. Meghan; Dutcher, Susan K.; Fox, David Thomas; Goodenough, Ursula; Jaworski, Jan; Holladay, Jonathan E.; Kramer, David M.; Koppisch, Andrew Thomas; Lipton, Mary S.; Marrone, Babetta Louise; McCormick, Margaret; Molnar, Istvan; Mott, John Blaine; Ogden, Kimberly L.; Panisko, Ellen A.; Pellegrini, Matteo; Polle, Juergen; Richardson, James W.; Sabarsky, Martin; Starkenburg, Shawn Robert; Stormo, Gary D.; Teshima, Munehiro; Twary, Scott Nicholas; Unkefer, Pat J.; Yuan, Joshua S.; Olivares, Jose Antonio

    2016-06-21

    In 2010,when the National Alliance for Advanced Biofuels and Bioproducts (NAABB) consortium began, little was known about the molecular basis of algal biomass or oil production. Very few algal genome sequences were available and efforts to identify the best-producing wild species through bioprospecting approaches had largely stalled after the U.S. Department of Energy's Aquatic Species Program. This lack of knowledge included how reduced carbon was partitioned into storage products like triglycerides or starch and the role played by metabolite remodeling in the accumulation of energy-dense storage products. Furthermore, genetic transformation and metabolic engineering approaches to improve algal biomass and oil yields were in their infancy. Genome sequencing and transcriptional profiling were becoming less expensive, however; and the tools to annotate gene expression profiles under various growth and engineered conditions were just starting to be developed for algae. It was in this context that an integrated algal biology program was introduced in the NAABB to address the greatest constraints limiting algal biomass yield. Our review describes the NAABB algal biology program, including hypotheses, research objectives, and strategies to move algal biology research into the twenty-first century and to realize the greatest potential of algae biomass systems to produce biofuels.

  2. Review of the algal biology program within the National Alliance for Advanced Biofuels and Bioproducts

    DOE PAGES

    Unkefer, Clifford Jay; Sayre, Richard Thomas; Magnuson, Jon K.; ...

    2016-06-21

    In 2010,when the National Alliance for Advanced Biofuels and Bioproducts (NAABB) consortium began, little was known about the molecular basis of algal biomass or oil production. Very few algal genome sequences were available and efforts to identify the best-producing wild species through bioprospecting approaches had largely stalled after the U.S. Department of Energy's Aquatic Species Program. This lack of knowledge included how reduced carbon was partitioned into storage products like triglycerides or starch and the role played by metabolite remodeling in the accumulation of energy-dense storage products. Furthermore, genetic transformation and metabolic engineering approaches to improve algal biomass and oilmore » yields were in their infancy. Genome sequencing and transcriptional profiling were becoming less expensive, however; and the tools to annotate gene expression profiles under various growth and engineered conditions were just starting to be developed for algae. It was in this context that an integrated algal biology program was introduced in the NAABB to address the greatest constraints limiting algal biomass yield. Our review describes the NAABB algal biology program, including hypotheses, research objectives, and strategies to move algal biology research into the twenty-first century and to realize the greatest potential of algae biomass systems to produce biofuels.« less

  3. 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.

  4. A Brief Literature Overview of Various Routes to Biorenewable Fuels from Lipids for the National Alliance for Advanced Biofuels and Bio-products (NAABB) Consortium

    SciTech Connect

    Albrecht, Karl O.; Hallen, Richard T.

    2011-03-29

    Renewable methods of producing transportation fuels are currently the focus of numerous large research efforts across the globe. Renewable fuel produced from algal lipids is one aspect of this research that could have profound implications on future transportation fuel requirements. However, technical challenges remain in several areas of algal-lipid-based fuels. These challenges include the identification and development of robust and productive algal species as well as extraction methods to recover the produced lipids. Not the least of these technical challenges is the conversion of the algae lipids to fungible fuels. This brief literature review focuses primarily on state-of-the-art “downstream” applications of producing fuel from fats and lipids, which can be applied to ongoing research with algae-derived lipids.

  5. Maintaining site productivity during biofuel harvest operations

    Treesearch

    Deborah Page-Dumoese; Mark Kimsey

    2012-01-01

    Demand for forest biomass for bioenergy production and other uses is expected to increase to four times the current level in the next one to five years. The search for alternative energy sources, including forest bioenergy, increases pressure on the productive capacity of our western forestlands. The questions are: Can forest soils in the western U.S. support more...

  6. Assessing the potential of polyculture to accelerate algal biofuel production

    DOE PAGES

    Newby, Deborah T.; Mathews, Teresa J.; Pate, Ron C.; ...

    2016-10-24

    To date, the algal biofuel industry has focused on the cultivation of monocultures of highly productive algal strains, but scaling up production remains challenging. However, algal monocultures are difficult to maintain because they are easily contaminated by wild algal strains, grazers, and pathogens. In contrast, theory suggests that polycultures (multispecies assemblages) can promote both ecosystem stability and productivity. A greater understanding of species interactions and how communities change with time will need to be developed before polycultures can be successfully applied to large-scale algal production efforts. Here in this paper we review the agricultural and ecological literature to explore opportunitiesmore » for increased annual biomass production through the use of algal polycultures. We discuss case studies where algal polycultures have been successfully maintained for industries other than the biofuel industry, as well as the few studies that have compared biomass production of algal polycultures to that of monocultures. Assemblages that include species with complementary traits are of particular promise. These assemblages have the potential not only to increase crop productivity and stability, but they may also be capable of utilizing natural resources (e.g. light, nutrients, water) more efficiently via tighter niche packing. Therefore, algal polycultures show promise for enhancing biomass productivity, enabling sustainable production and reducing overall production costs.« less

  7. Assessing the potential of polyculture to accelerate algal biofuel production

    SciTech Connect

    Newby, Deborah T.; Mathews, Teresa J.; Pate, Ron C.; Huesemann, Michael H.; Lane, Todd W.; Wahlen, Bradley D.; Mandal, Shovon; Engler, Robert K.; Feris, Kevin P.; Shurin, Jon B.

    2016-10-24

    To date, the algal biofuel industry has focused on the cultivation of monocultures of highly productive algal strains, but scaling up production remains challenging. However, algal monocultures are difficult to maintain because they are easily contaminated by wild algal strains, grazers, and pathogens. In contrast, theory suggests that polycultures (multispecies assemblages) can promote both ecosystem stability and productivity. A greater understanding of species interactions and how communities change with time will need to be developed before polycultures can be successfully applied to large-scale algal production efforts. Here in this paper we review the agricultural and ecological literature to explore opportunities for increased annual biomass production through the use of algal polycultures. We discuss case studies where algal polycultures have been successfully maintained for industries other than the biofuel industry, as well as the few studies that have compared biomass production of algal polycultures to that of monocultures. Assemblages that include species with complementary traits are of particular promise. These assemblages have the potential not only to increase crop productivity and stability, but they may also be capable of utilizing natural resources (e.g. light, nutrients, water) more efficiently via tighter niche packing. Therefore, algal polycultures show promise for enhancing biomass productivity, enabling sustainable production and reducing overall production costs.

  8. Assessing the potential of polyculture to accelerate algal biofuel production

    SciTech Connect

    Newby, Deborah T.; Mathews, Teresa J.; Pate, Ron C.; Huesemann, Michael H.; Lane, Todd W.; Wahlen, Bradley D.; Mandal, Shovon; Engler, Robert K.; Feris, Kevin P.; Shurin, Jon B.

    2016-10-24

    To date, the algal biofuel industry has focused on the cultivation of monocultures of highly productive algal strains, but scaling up production remains challenging. However, algal monocultures are difficult to maintain because they are easily contaminated by wild algal strains, grazers, and pathogens. In contrast, theory suggests that polycultures (multispecies assemblages) can promote both ecosystem stability and productivity. A greater understanding of species interactions and how communities change with time will need to be developed before polycultures can be successfully applied to large-scale algal production efforts. Here in this paper we review the agricultural and ecological literature to explore opportunities for increased annual biomass production through the use of algal polycultures. We discuss case studies where algal polycultures have been successfully maintained for industries other than the biofuel industry, as well as the few studies that have compared biomass production of algal polycultures to that of monocultures. Assemblages that include species with complementary traits are of particular promise. These assemblages have the potential not only to increase crop productivity and stability, but they may also be capable of utilizing natural resources (e.g. light, nutrients, water) more efficiently via tighter niche packing. Therefore, algal polycultures show promise for enhancing biomass productivity, enabling sustainable production and reducing overall production costs.

  9. Assessing the potential of polyculture to accelerate algal biofuel production

    DOE PAGES

    Newby, Deborah T.; Mathews, Teresa J.; Pate, Ron C.; ...

    2016-10-24

    To date, the algal biofuel industry has focused on the cultivation of monocultures of highly productive algal strains, but scaling up production remains challenging. However, algal monocultures are difficult to maintain because they are easily contaminated by wild algal strains, grazers, and pathogens. In contrast, theory suggests that polycultures (multispecies assemblages) can promote both ecosystem stability and productivity. A greater understanding of species interactions and how communities change with time will need to be developed before polycultures can be successfully applied to large-scale algal production efforts. Here in this paper we review the agricultural and ecological literature to explore opportunitiesmore » for increased annual biomass production through the use of algal polycultures. We discuss case studies where algal polycultures have been successfully maintained for industries other than the biofuel industry, as well as the few studies that have compared biomass production of algal polycultures to that of monocultures. Assemblages that include species with complementary traits are of particular promise. These assemblages have the potential not only to increase crop productivity and stability, but they may also be capable of utilizing natural resources (e.g. light, nutrients, water) more efficiently via tighter niche packing. Therefore, algal polycultures show promise for enhancing biomass productivity, enabling sustainable production and reducing overall production costs.« less

  10. 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.

  11. Production of biofuels via bio-oil upgrading & refining

    SciTech Connect

    Elliott, Douglas C.

    2016-03-18

    This chapter provides cursory reviews of biomass liquefaction, relevant petroleum processing technology, and relevant model compound studies. More detail is provided for upgrading of biomass liquefaction products, including an overview of potential fractionation and catalytic processing methods, hydroprocessing as the primary means of interest, scale of operation, operating conditions and catalysts, and product properties. Batch results are included where needed to provide a more complete narrative, but continuous-flow operations are emphasized as being more informative. Liquid fuel products from biomass through direct liquefaction and hydroprocessing are discussed, such as fuel properties based on chemical analysis and comparison of petroleum fuels and biofuels.

  12. Cofactor engineering for more efficient production of chemicals and biofuels.

    PubMed

    Wang, Meng; Chen, Biqiang; Fang, Yunming; Tan, Tianwei

    2017-09-20

    Cofactors are involved in numerous intracellular reactions and critically influence redox balance and cellular metabolism. Cofactor engineering can support and promote the biocatalysis process, even help driving thermodynamically unfavorable reactions forwards. To achieve efficient production of chemicals and biofuels, cofactor engineering strategies such as altering cofactor supply or modifying reactants' cofactor preference have been developed to maintain redox balance. This review focuses primarily on the effects of cofactor engineering on carbon and energy metabolism. Coupling carbon metabolism with cofactor engineering can promote large-scale production, and even offer possibilities for producing new products or converting new materials. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Tailoring lignin biosynthesis for efficient and sustainable biofuel production.

    PubMed

    Liu, Chang-Jun; Cai, Yuanheng; Zhang, Xuebin; Gou, Mingyue; Yang, Huijun

    2014-12-01

    Increased global interest in a bio-based economy has reinvigorated the research on the cell wall structure and composition in plants. In particular, the study of plant lignification has become a central focus, with respect to its intractability and negative impact on the utilization of the cell wall biomass for producing biofuels and bio-based chemicals. Striking progress has been achieved in the last few years both on our fundamental understanding of lignin biosynthesis, deposition and assembly, and on the interplay of lignin synthesis with the plant growth and development. With the knowledge gleaned from basic studies, researchers are now able to invent and develop elegant biotechnological strategies to sophisticatedly manipulate the quantity and structure of lignin and thus to create economically viable bioenergy feedstocks. These concerted efforts open an avenue for the commercial production of cost-competitive biofuel to meet our energy needs.

  14. 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, Luísa; 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.

  15. Estimation of economic impacts of cellulosic biofuel production: a comparative analysis of three biofuel pathways: Economic impacts of biofuel production

    SciTech Connect

    Zhang, Yimin; Goldberg, Marshall; Tan, Eric; Meyer, Pimphan Aye

    2016-03-07

    The development of a cellulosic biofuel industry utilizing domestic biomass resources is expected to create opportunities for economic growth resulting from the construction and operation of new biorefineries. We applied an economic input-output model to estimate potential economic impacts, particularly gross job growth, resulting from the construction and operation of biorefineries using three different technology pathways: 1) cellulosic ethanol via biochemical conversion in Iowa, 2) renewable diesel blendstock via biological conversion in Georgia, and 3) renewable diesel and gasoline blendstock via fast pyrolysis in Mississippi. Combining direct, indirect, and induced effects, capital investment associated with the construction of a biorefinery processing 2,000 dry metric tons of biomass per day (DMT/day) could yield between 5,960 and 8,470 full-time equivalent (FTE) jobs during the construction period. Fast pyrolysis biorefineries produce the most jobs on a project level thanks to the highest capital requirement among the three pathways. Normalized for one million dollars of capital investment, the fast pyrolysis biorefineries are estimated to yield slighter more jobs (12.1 jobs) than the renewable diesel (11.8 jobs) and the cellulosic ethanol (11.6 jobs) biorefineries. While operating biorefineries is not labor-intensive, the annual operation of a 2,000 DMT/day biorefinery could support between 720 and 970 jobs when the direct, indirect, and induced effects are considered. The major factor, which results in the variations among the three pathways, is the type of biomass feedstock used for biofuels. The agriculture/forest, services, and trade industries are the primary sectors that will benefit from the ongoing operation of biorefineries.

  16. Biofuel production from Jerusalem artichoke tuber inulins

    USDA-ARS?s Scientific Manuscript database

    Jerusalem artichoke has high productivity of tubers that are rich in inulins, a fructan polymer. These inulins can be easily broken down into fructose and glucose for conversion into ethanol by fermentation. This review focuses on tuber and inulin yields, effect of cultivar and environment on tuber ...

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

    USDA-ARS?s Scientific Manuscript database

    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-...

  18. Maturation of biomass-to-biofuels conversion technology pathways for rapid expansion of biofuels production: A system dynamics perspective

    DOE PAGES

    Vimmerstedt, Laura J.; Bush, Brian W.; Hsu, Dave D.; ...

    2014-08-12

    The Biomass Scenario Model (BSM) is a system-dynamics simulation model intended to explore the potential for rapid expansion of the biofuels industry. The model is not predictive — it uses scenario assumptions based on various types of data to simulate industry development, emphasizing how incentives and technological learning-by-doing might accelerate industry growth. The BSM simulates major sectors of the biofuels industry, including feedstock production and logistics, conversion, distribution, and end uses, as well as interactions among sectors. The model represents conversion of biomass to biofuels as a set of technology pathways, each of which has allowable feedstocks, capital and operatingmore » costs, allowable products, and other defined characteristics. This study and the BSM address bioenergy modeling analytic needs that were identified in recent literature reviews. Simulations indicate that investments are most effective at expanding biofuels production through learning-by-doing when they are coordinated with respect to timing, pathway, and target sector within the biofuels industry. Effectiveness metrics include timing and magnitude of increased production, incentive cost and cost effectiveness, and avoidance of windfall profits. Investment costs and optimal investment targets have inherent risks and uncertainties, such as the relative value of investment in more-mature versus less mature pathways. These can be explored through scenarios, but cannot be precisely predicted. Dynamic competition, including competition for cellulosic feedstocks and ethanol market shares, intensifies during times of rapid growth. Ethanol production increases rapidly, even up to Renewable Fuel Standards-targeted volumes of biofuel, in simulations that allow higher blending proportions of ethanol in gasoline-fueled vehicles. Published 2014. This document is a U.S. Government work and is in the public domain in the USA. Biofuels, Bioproducts, Biorefining published by John

  19. Maturation of biomass-to-biofuels conversion technology pathways for rapid expansion of biofuels production: A system dynamics perspective

    SciTech Connect

    Vimmerstedt, Laura J.; Bush, Brian W.; Hsu, Dave D.; Inman, Daniel; Peterson, Steven O.

    2014-08-12

    The Biomass Scenario Model (BSM) is a system-dynamics simulation model intended to explore the potential for rapid expansion of the biofuels industry. The model is not predictive — it uses scenario assumptions based on various types of data to simulate industry development, emphasizing how incentives and technological learning-by-doing might accelerate industry growth. The BSM simulates major sectors of the biofuels industry, including feedstock production and logistics, conversion, distribution, and end uses, as well as interactions among sectors. The model represents conversion of biomass to biofuels as a set of technology pathways, each of which has allowable feedstocks, capital and operating costs, allowable products, and other defined characteristics. This study and the BSM address bioenergy modeling analytic needs that were identified in recent literature reviews. Simulations indicate that investments are most effective at expanding biofuels production through learning-by-doing when they are coordinated with respect to timing, pathway, and target sector within the biofuels industry. Effectiveness metrics include timing and magnitude of increased production, incentive cost and cost effectiveness, and avoidance of windfall profits. Investment costs and optimal investment targets have inherent risks and uncertainties, such as the relative value of investment in more-mature versus less mature pathways. These can be explored through scenarios, but cannot be precisely predicted. Dynamic competition, including competition for cellulosic feedstocks and ethanol market shares, intensifies during times of rapid growth. Ethanol production increases rapidly, even up to Renewable Fuel Standards-targeted volumes of biofuel, in simulations that allow higher blending proportions of ethanol in gasoline-fueled vehicles. Published 2014. This document is a U.S. Government work and is in the public domain in the USA. Biofuels, Bioproducts, Biorefining published by John Wiley

  20. Optimization of Biofuel Production From Transgenic Microalgae

    DTIC Science & Technology

    2013-02-27

    photosynthesis by up to 80%. We have also completed the proteome analysis for the diatom Cyclotella when induced to accumulate oil after silicon...identification of several proteins when over-expressed in transgenic algae enhance photosynthesis by up to 80%. We have also completed the proteome...respiration Photosynthesis /Calvin Cycle Figure 1. Proteins that change most in abundance following glucose-induced oil production. Many of

  1. 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.

  2. 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.

  3. Environmental indicators for sustainable production of algal biofuels

    DOE PAGES

    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

  4. Downgrading recent estimates of land available for biofuel production.

    PubMed

    Fritz, Steffen; See, Linda; van der Velde, Marijn; Nalepa, Rachel A; Perger, Christoph; Schill, Christian; McCallum, Ian; Schepaschenko, Dmitry; Kraxner, Florian; Cai, Ximing; Zhang, Xiao; Ortner, Simone; Hazarika, Rubul; Cipriani, Anna; Di Bella, Carlos; Rabia, Ahmed H; Garcia, Alfredo; Vakolyuk, Mar'yana; Singha, Kuleswar; Beget, Maria E; Erasmi, Stefan; Albrecht, Franziska; Shaw, Brian; Obersteiner, Michael

    2013-02-05

    Recent estimates of additional land available for bioenergy production range from 320 to 1411 million ha. These estimates were generated from four scenarios regarding the types of land suitable for bioenergy production using coarse-resolution inputs of soil productivity, slope, climate, and land cover. In this paper, these maps of land availability were assessed using high-resolution satellite imagery. Samples from these maps were selected and crowdsourcing of Google Earth images was used to determine the type of land cover and the degree of human impact. Based on this sample, a set of rules was formulated to downward adjust the original estimates for each of the four scenarios that were previously used to generate the maps of land availability for bioenergy production. The adjusted land availability estimates range from 56 to 1035 million ha depending upon the scenario and the ruleset used when the sample is corrected for bias. Large forest areas not intended for biofuel production purposes were present in all scenarios. However, these numbers should not be considered as definitive estimates but should be used to highlight the uncertainty in attempting to quantify land availability for biofuel production when using coarse-resolution inputs with implications for further policy development.

  5. 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

  6. Fermentation broth components influence droplet coalescence and hinder advanced biofuel recovery during fermentation.

    PubMed

    Heeres, Arjan S; Schroën, Karin; Heijnen, Joseph J; van der Wielen, Luuk A M; Cuellar, Maria C

    2015-08-01

    Developments in synthetic biology enabled the microbial production of long chain hydrocarbons, which can be used as advanced biofuels in aviation or transportation. Currently, these fuels are not economically competitive due to their production costs. The current process offers room for improvement: by utilizing lignocellulosic feedstock, increasing microbial yields, and using cheaper process technology. Gravity separation is an example of the latter, for which droplet growth by coalescence is crucial. The aim of this study was to study the effect of fermentation broth components on droplet coalescence. Droplet coalescence was measured using two setups: a microfluidic chip and regular laboratory scale stirred vessel (2 L). Some fermentation broth components had a large impact on droplet coalescence. Especially components present in hydrolysed cellulosic biomass and mannoproteins from the yeast cell wall retard coalescence. To achieve a technically feasible gravity separation that can be integrated with the fermentation, the negative effects of these components on coalescence should be minimized. This could be achieved by redesign of the fermentation medium or adjusting the fermentation conditions, aiming to minimize the release of surface active components by the microorganisms. This way, another step can be made towards economically feasible advanced biofuel production. © 2015 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-Non-Commercial-NoDerivs Licence, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

  7. [Application of systems biology and synthetic biology in strain improvement for biofuel production].

    PubMed

    Zhao, Xinqing; Bai, Fengwu; Li, Yin

    2010-07-01

    Biofuels are renewable and environmentally friendly, but high production cost makes them economically not competitive, and the development of robust strains is thus one of the prerequisites. In this article, strain improvement studies based on the information from systems biology studies are reviewed, with a focus on their applications on stress tolerance improvement. Furthermore, the contribution of systems biology, synthetic biology and metabolic engineering in strain development for biofuel production is discussed, with an expectation for developing more robust strains for biofuel production.

  8. Nanostructured material-based biofuel cells: recent advances and future prospects.

    PubMed

    Zhao, Cui-E; Gai, Panpan; Song, Rongbin; Chen, Ying; Zhang, Jianrong; Zhu, Jun-Jie

    2017-03-06

    During the past decade, biofuel cells (BFCs) have emerged as an emerging technology on account of their ability to directly generate electricity from biologically renewable catalysts and fuels. Due to the boost in nanotechnology, significant advances have been accomplished in BFCs. Although it is still challenging to promote the performance of BFCs, adopting nanostructured materials for BFC construction has been extensively proposed as an effective and promising strategy to achieve high energy production. In this review, we presented the major novel nanostructured materials applied for BFCs and highlighted the breakthroughs in this field. Based on different natures of the bio-catalysts and electron transfer process at the bio-electrode surfaces, the fundamentals of BFC systems, including enzymatic biofuel cells (EBFCs) and microbial fuel cells (MFCs), have been elucidated. In particular, the principle of electrode materials design has been detailed in terms of enhancing electrical communications between biological catalysts and electrodes. Furthermore, we have provided the applications of BFCs and potential challenges of this technology.

  9. 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.

  10. 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.

  11. 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. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Microwave-assisted pyrolysis of biomass for liquid biofuels production.

    PubMed

    Yin, Chungen

    2012-09-01

    Production of 2nd-generation biofuels from biomass residues and waste feedstock is gaining great concerns worldwide. Pyrolysis, a thermochemical conversion process involving rapid heating of feedstock under oxygen-absent condition to moderate temperature and rapid quenching of intermediate products, is an attractive way for bio-oil production. Various efforts have been made to improve pyrolysis process towards higher yield and quality of liquid biofuels and better energy efficiency. Microwave-assisted pyrolysis is one of the promising attempts, mainly due to efficient heating of feedstock by "microwave dielectric heating" effects. This paper presents a state-of-the-art review of microwave-assisted pyrolysis of biomass. First, conventional fast pyrolysis and microwave dielectric heating is briefly introduced. Then microwave-assisted pyrolysis process is thoroughly discussed stepwise from biomass pretreatment to bio-oil collection. The existing efforts are summarized in a table, providing a handy overview of the activities (e.g., feedstock and pretreatment, reactor/pyrolysis conditions) and findings (e.g., pyrolysis products) of various investigations.

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

    PubMed

    Menetrez, Marc Y

    2012-07-03

    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.

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. The role of biochemical engineering in the production of biofuels from microalgae.

    PubMed

    Costa, Jorge Alberto Vieira; de Morais, Michele Greque

    2011-01-01

    Environmental changes that have occurred due to the use of fossil fuels have driven the search for alternative sources that have a lower environmental impact. First-generation biofuels were derived from crops such as sugar cane, corn and soybean, which contribute to water scarcity and deforestation. Second-generation biofuels originated from lignocellulose agriculture and forest residues, however these needed large areas of land that could be used for food production. Based on technology projections, the third generation of biofuels will be derived from microalgae. Microalgae are considered to be an alternative energy source without the drawbacks of the first- and second-generation biofuels. Depending upon the growing conditions, microalgae can produce biocompounds that are easily converted into biofuels. The biofuels from microalgae are an alternative that can keep the development of human activity in harmony with the environment. This study aimed to present the main biofuels that can be derived from microalgae. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. A perspective: photosynthetic production of fatty acid-based biofuels in genetically engineered cyanobacteria.

    PubMed

    Lu, Xuefeng

    2010-01-01

    Biofuels are expected to play a key role in the development of a sustainable, economical and environmentally safe source of energy. Microbes offer great potential for applications in technology based biofuel production. Three fundamental questions need to be addressed in order for the development of microbial synthesis of biofuels to be successful. Firstly, what energy resource platform could be used to make biofuels. Secondly, what type of biofuel is the ideal fuel molecule that should be targeted. Finally, what microbial system could be used to transform energy resources into the targeted biofuel molecules. In this perspective, the potential of using photosynthetic microbes (cyanobacteria in particular) in the solar energy driven conversion of carbon dioxide to fatty acid-based biofuels is explored. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Potential of lipid metabolism in marine diatoms for biofuel production.

    PubMed

    d'Ippolito, Giuliana; Sardo, Angela; Paris, Debora; Vella, Filomena Monica; Adelfi, Maria Grazia; Botte, Pierpaolo; Gallo, Carmela; Fontana, Angelo

    2015-01-01

    Diatoms are an ecologically relevant group of microalgae that are not commonly considered for bio-oil production even if they are responsible for massive blooms at sea. Seventeen diatom species were screened for their capacity to produce biomass and lipids, in relation to their growth rate. Triglyceride levels were also assessed as a preferential source of biofuels. Using statistical analysis, two centric diatoms, Thalassiosira weissflogii and Cyclotella cryptica, were selected as good candidates for oil production. Lipid levels significantly increased when the two diatoms were cultivated in a two-stage process under nitrogen limitation. The effect was less pronounced in cultures where silicon was reduced to 20% of the standard supply. Nitrogen limitation did not affect growth rates but led to lipid remodeling and de novo synthesis of triacylglycerols. Triacylglycerols in T. weissflogii and C. cryptica can account for up to 82% and 88% of total glycerolipids, thereby suggesting that the two species are promising candidates for large-scale experimentation for biofuel production.

  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.

  2. Water quality under increased biofuel production and future climate change and uncertainty

    NASA Astrophysics Data System (ADS)

    Demissie, Y. K.; Yan, E.

    2015-12-01

    Over the past decade, biofuel has emerged as an important renewable energy source to supplement gasoline and reduce the associated greenhouse gas emission. Many countries, for instant, have adopted biofuel production goals to blend 10% or more of gasoline with biofuels within 10 to 20 years. However, meeting these goals requires sustainable production of biofuel feedstock which can be challenging under future change in climate and extreme weather conditions, as well as the likely impacts of biofuel feedstock production on water quality and availability. To understand this interrelationship and the combined effects of increased biofuel production and climate change on regional and local water resources, we have performed watershed hydrology and water quality analyses for the Ohio River Basin. The basin is one of the major biofuel feedstock producing region in the United States, which also currently contributes about half of the flow and one third of phosphorus and nitrogen loadings to the Mississippi River that eventually flows to the Gulf of Mexico. The analyses integrate future scenarios and climate change and biofuel development through various mixes of landuse and agricultural management changes and examine their potential impacts on regional and local hydrology, water quality, soil erosion, and agriculture productivity. The results of the study are expected to provide much needed insight about the sustainability of large-scale biofuel feedstock production under the future climate change and uncertainty, and helps to further optimize the feedstock production taking into consideration the water-use efficiency.

  3. 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

  4. 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.

  5. Recent advances on enzymatic glucose/oxygen and hydrogen/oxygen biofuel cells: Achievements and limitations

    NASA Astrophysics Data System (ADS)

    Cosnier, Serge; Gross, Andrew J.; Le Goff, Alan; Holzinger, Michael

    2016-09-01

    The possibility of producing electrical power from chemical energy with biological catalysts has induced the development of biofuel cells as viable energy sources for powering portable and implanted electronic devices. These power sources employ biocatalysts, called enzymes, which are highly specific and catalytic towards the oxidation of a biofuel and the reduction of oxygen or hydrogen peroxide. Enzymes, on one hand, are promising candidates to replace expensive noble metal-based catalysts in fuel cell research. On the other hand, they offer the exciting prospect of a new generation of fuel cells which harvest energy from body fluids. Biofuel cells which use glucose as a fuel are particularly interesting for generating electricity to power electronic devices inside a living body. Hydrogen consuming biofuel cells represent an emerging alternative to platinum catalysts due to comparable efficiencies and the capability to operate at lower temperatures. Currently, these technologies are not competitive with existing commercialised fuel cell devices due to limitations including insufficient power outputs and lifetimes. The advantages and challenges facing glucose biofuel cells for implantation and hydrogen biofuel cells will be summarised along with recent promising advances and the future prospects of these exotic energy-harvesting devices.

  6. 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

  7. Enhancing microalgal photosynthesis and productivity in wastewater treatment high rate algal ponds for biofuel production.

    PubMed

    Sutherland, Donna L; Howard-Williams, Clive; Turnbull, Matthew H; Broady, Paul A; Craggs, Rupert J

    2015-05-01

    With microalgal biofuels currently receiving much attention, there has been renewed interest in the combined use of high rate algal ponds (HRAP) for wastewater treatment and biofuel production. This combined use of HRAPs is considered to be an economically feasible option for biofuel production, however, increased microalgal productivity and nutrient removal together with reduced capital costs are needed before it can be commercially viable. Despite HRAPs being an established technology, microalgal photosynthesis and productivity is still limited in these ponds and is well below the theoretical maximum. This paper critically evaluates the parameters that limit microalgal light absorption and photosynthesis in wastewater HRAPs and examines biological, chemical and physical options for improving light absorption and utilisation, with the view of enhancing biomass production and nutrient removal.

  8. Cyanobacterial metabolic engineering for biofuel and chemical production.

    PubMed

    Oliver, Neal J; Rabinovitch-Deere, Christine A; Carroll, Austin L; Nozzi, Nicole E; Case, Anna E; Atsumi, Shota

    2016-12-01

    Rising levels of atmospheric CO2 are contributing to the global greenhouse effect. Large scale use of atmospheric CO2 may be a sustainable and renewable means of chemical and liquid fuel production to mitigate global climate change. Photosynthetic organisms are an ideal platform for efficient, natural CO2 conversion to a broad range of chemicals. Cyanobacteria are especially attractive for these purposes, due to their genetic malleability and relatively fast growth rate. Recent years have yielded a range of work in the metabolic engineering of cyanobacteria and have led to greater knowledge of the host metabolism. Understanding of endogenous and heterologous carbon regulation mechanisms leads to the expansion of productive capacity and chemical variety. This review discusses the recent progress in metabolic engineering of cyanobacteria for biofuel and bulk chemical production since 2014.

  9. BioFuelDB: a database and prediction server of enzymes involved in biofuels production.

    PubMed

    Chaudhary, Nikhil; Gupta, Ankit; Gupta, Sudheer; Sharma, Vineet K

    2017-01-01

    In light of the rapid decrease in fossils fuel reserves and an increasing demand for energy, novel methods are required to explore alternative biofuel production processes to alleviate these pressures. A wide variety of molecules which can either be used as biofuels or as biofuel precursors are produced using microbial enzymes. However, the common challenges in the industrial implementation of enzyme catalysis for biofuel production are the unavailability of a comprehensive biofuel enzyme resource, low efficiency of known enzymes, and limited availability of enzymes which can function under extreme conditions in the industrial processes. We have developed a comprehensive database of known enzymes with proven or potential applications in biofuel production through text mining of PubMed abstracts and other publicly available information. A total of 131 enzymes with a role in biofuel production were identified and classified into six enzyme classes and four broad application categories namely 'Alcohol production', 'Biodiesel production', 'Fuel Cell' and 'Alternate biofuels'. A prediction tool 'Benz' was developed to identify and classify novel homologues of the known biofuel enzyme sequences from sequenced genomes and metagenomes. 'Benz' employs a hybrid approach incorporating HMMER 3.0 and RAPSearch2 programs to provide high accuracy and high speed for prediction. Using the Benz tool, 153,754 novel homologues of biofuel enzymes were identified from 23 diverse metagenomic sources. The comprehensive data of curated biofuel enzymes, their novel homologs identified from diverse metagenomes, and the hybrid prediction tool Benz are presented as a web server which can be used for the prediction of biofuel enzymes from genomic and metagenomic datasets. The database and the Benz tool is publicly available at http://metabiosys.iiserb.ac.in/biofueldb& http://metagenomics.iiserb.ac.in/biofueldb.

  10. Improving photosynthesis and metabolic networks for the competitive production of phototroph-derived biofuels.

    PubMed

    Work, Victoria H; D'Adamo, Sarah; Radakovits, Randor; Jinkerson, Robert E; Posewitz, Matthew C

    2012-06-01

    To improve bioenergy production from photosynthetic microorganisms it is necessary to optimize an extensive network of highly integrated biological processes. Systematic advances in pathway engineering and culture modification have resulted in strains with increased yields of biohydrogen, lipids, and carbohydrates, three bioenergy foci. However, additional improvements in photosynthetic efficiency are necessary to establish a viable system for biofuel production. Advances in optimizing light capture, energy transfer, and carbon fixation are essential, as the efficiencies of these processes are the principal determinants of productivity. However, owing to their regulatory, catalytic, and structural complexities, manipulating these pathways poses considerable challenges. This review covers novel developments in the optimization of photosynthesis, carbon fixation, and metabolic pathways for the synthesis of targeted bioenergy carriers. Copyright © 2011 Elsevier Ltd. All rights reserved.

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

    USDA-ARS?s Scientific Manuscript database

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

    Treesearch

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

    2011-01-01

    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...

  13. Burkholderia cepacia lipase is a promising biocatalyst for biofuel production.

    PubMed

    Sasso, Francesco; Natalello, Antonino; Castoldi, Simone; Lotti, Marina; Santambrogio, Carlo; Grandori, Rita

    2016-07-01

    Lipases resistant to inhibition and denaturation by methanol are valuable tools for biotechnological applications, in particular for biofuel production. Microbial lipases have attracted a great deal of interest because of their stability at high concentrations of organic solvents. Burkholderia cepacia lipase (BCL) is tested here for robustness towards methanol in terms of conformational stability and catalytic activity in transesterification assays. This lipase turns out to be even more tolerant than the homologous and better characterized enzyme from Burkholderia glumae. BCL unfolding transition, as monitored by far-UV circular dichroism (CD) and intrinsic fluorescence, displays a Tm above 60°C in the presence of 50% methanol. The protein unfolds at low pH, and the organic solvent affects the nature of the denatured state under acidic conditions. The protein performs well in transesterification assays upon prolonged incubations at high methanol concentrations. BCL is highly tolerant to methanol and displays particularly high conformational stability under conditions employed for transesterification reactions. These features depict BCL as a promising enzyme for biofuel industry.

  14. Review of the harvesting and extraction program within the National Alliance for Advanced Biofuels and Bioproducts

    DOE PAGES

    Marrone, Babetta L.; Lacey, Ronald E.; Anderson, Daniel B.; ...

    2017-08-07

    Energy-efficient and scalable harvesting and lipid extraction processes must be developed in order for the algal biofuels and bioproducts industry to thrive. The major challenge for harvesting is the handling of large volumes of cultivation water to concentrate low amounts of biomass. For lipid extraction, the major energy and cost drivers are associated with disrupting the algae cell wall and drying the biomass before solvent extraction of the lipids. Here we review the research and development conducted by the Harvesting and Extraction Team during the 3-year National Alliance for Advanced Biofuels and Bioproducts (NAABB) algal consortium project. The harvesting andmore » extraction team investigated five harvesting and three wet extraction technologies at lab bench scale for effectiveness, and conducted a techoeconomic study to evaluate their costs and energy efficiency compared to available baseline technologies. Based on this study, three harvesting technologies were selected for further study at larger scale. We evaluated the selected harvesting technologies: electrocoagulation, membrane filtration, and ultrasonic harvesting, in a field study at minimum scale of 100 L/h. None of the extraction technologies were determined to be ready for scale-up; therefore, an emerging extraction technology (wet solvent extraction) was selected from industry to provide scale-up data and capabilities to produce lipid and lipid-extracted materials for the NAABB program. One specialized extraction/adsorption technology was developed that showed promise for recovering high value co-products from lipid extracts. Overall, the NAABB Harvesting and Extraction Team improved the readiness level of several innovative, energy efficient technologies to integrate with algae production processes and captured valuable lessons learned about scale-up challenges.« less

  15. Climatic impacts of managed landscapes for sustainable biofuel feedstocks production.

    NASA Astrophysics Data System (ADS)

    Gelfand, I.; Kravchenko, A. N.; Hamilton, S. K.; Jackson, R. D.; Thelen, K.; Robertson, G. P.

    2016-12-01

    Sustainable production of biofuels cannot be achieved without multiple-use landscapes where food, feed, and fuel can be co-produced without environmental harm. Here we use field level measurements in seven biofuel feedstock production systems grown under similar climatic conditions, but on different soils in two Midwestern (USA) states to understand their relative climatic impacts. We studied annual corn stover, and 6 perennial ecosystems including three polycultures: successional vegetation, restored prairie and a 3-species grass mix; and 3 monocultures: poplar, switchgrass, and miscanthus. All studied ecosystems were grown in replicated plots on moderately fertile soils of SW Michigan and highly fertile soils of central Wisconsin. We measured components of greenhouse gas (GHG) balances over 6 years. On the fertile soil perennial monocultures had GHG emission reductions potentials of 53% relative to fossil fuels, while polycultures had 64% reduction; corn stover had an 84% emissions reduction. Net sequestration ranged from 0.6 MgCO2e ha-1yr-1 (successional vegetation) to 3.1 MgCO2e ha-1yr-1, (corn stover). Among feedstocks produced on less fertile soils, perennial monocultures had GHG emissions reduction of 80%, and polycultures had emission reduction of 54%; miscanthus and poplar exhibited the largest sequestration potentials of 5.9 and 3.9 MgCO2e ha-1yr-1 respectively, while polycultures sequestered less then 1.0 MgCO2e ha-1yr-1 on average and corn stover was intermediate with 1.4 MgCO2e ha-1yr-1. All studied systems averaged energy production of 30 GJ ha-1 yr-1, except miscanthus (71 GJ ha-1 yr-1) and successional vegetation (20 GJ ha-1 yr-1). Our results inform the design of multiple-use landscapes: more fertile soils could produce food and feed with residuals collected for bioethanol production and more marginal soils could be used for various poly- or mono-cultures of purpose grown biofuel feedstocks but with differential climate benefits.

  16. Genomic Advances to Improve Biomass for Biofuels (LBNL Science at the Theater)

    SciTech Connect

    Rokhsar, Daniel

    2008-02-11

    Lawrence Berkeley National Lab bioscientist Daniel Rokhsar discusses genomic advances to improve biomass for biofuels. He presented his talk Feb. 11, 2008 in Berkeley, California as part of Berkeley Lab's community lecture series. Rokhsar works with the U.S. Department of Energy's Joint Genome Institute and Berkeley Lab's Genomics Division.

  17. Genomic Advances to Improve Biomass for Biofuels (LBNL Science at the Theater)

    ScienceCinema

    Rokhsar, Daniel

    2016-07-12

    Lawrence Berkeley National Lab bioscientist Daniel Rokhsar discusses genomic advances to improve biomass for biofuels. He presented his talk Feb. 11, 2008 in Berkeley, California as part of Berkeley Lab's community lecture series. Rokhsar works with the U.S. Department of Energy's Joint Genome Institute and Berkeley Lab's Genomics Division.

  18. Iron oxide filled magnetic carbon nanotube-enzyme conjugates for recycling of amyloglucosidase: toward useful applications in biofuel production process.

    PubMed

    Goh, Wei Jiang; Makam, Venkata S; Hu, Jun; Kang, Lifeng; Zheng, Minrui; Yoong, Sia Lee; Udalagama, Chammika N B; Pastorin, Giorgia

    2012-12-11

    Biofuels are fast advancing as a new research area to provide alternative sources of sustainable and clean energy. Recent advances in nanotechnology have sought to improve the efficiency of biofuel production, enhancing energy security. In this study, we have incorporated iron oxide nanoparticles into single-walled carbon nanotubes (SWCNTs) to produce magnetic single-walled carbon nanotubes (mSWCNTs). Our objective is to bridge both nanotechnology and biofuel production by immobilizing the enzyme, Amyloglucosidase (AMG), onto mSWCNTs using physical adsorption and covalent immobilization, with the aim of recycling the immobilized enzyme, toward useful applications in biofuel production processes. We have demonstrated that the enzyme retains a certain percentage of its catalytic efficiency (up to 40%) in starch prototype biomass hydrolysis when used repeatedly (up to ten cycles) after immobilization on mSWCNTs, since the nanotubes can be easily separated from the reaction mixture using a simple magnet. The enzyme loading, activity, and structural changes after immobilization onto mSWCNTs were also studied. In addition, we have demonstrated that the immobilized enzyme retains its activity when stored at 4 °C for at least one month. These results, combined with the unique intrinsic properties of the nanotubes, pave the way for greater efficiency in carbon nanotube-enzyme bioreactors and reduced capital costs in industrial enzyme systems.

  19. Onsite Army Biofuel Production: Opportunities, Thresholds and Considerations

    DTIC Science & Technology

    2013-09-30

    use of biofuels. The Army lacks a specific management plan to develop and produce cellu- losic biofuels. Critics envision land grabs, deforestation ...support tool to assist installations in evaluating potential alternative energy sources and associated cost/ benefits . The intent was to develop and...releases of greenhouse gases can be expected, thereby cre- ating a biofuel carbon debt and effectively offsetting any benefits derived from replacement

  20. Biomass recalcitrance: engineering plants and enzymes for biofuels production.

    PubMed

    Himmel, Michael E; Ding, Shi-You; Johnson, David K; Adney, William S; Nimlos, Mark R; Brady, John W; Foust, Thomas D

    2007-02-09

    Lignocellulosic biomass has long been recognized as a potential sustainable source of mixed sugars for fermentation to biofuels and other biomaterials. Several technologies have been developed during the past 80 years that allow this conversion process to occur, and the clear objective now is to make this process cost-competitive in today's markets. Here, we consider the natural resistance of plant cell walls to microbial and enzymatic deconstruction, collectively known as "biomass recalcitrance." It is this property of plants that is largely responsible for the high cost of lignocellulose conversion. To achieve sustainable energy production, it will be necessary to overcome the chemical and structural properties that have evolved in biomass to prevent its disassembly.

  1. 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.

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

    SciTech Connect

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

    2015-10-23

    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 in this paper we review synthetic metabolic pathways based on fatty acid and isoprenoid metabolism to produce alkanes and other molecules suitable as biofuels. Lastly, we further discuss engineering strategies to optimize engineered biosynthetic routes, as well as the potential of synthetic biology for sustainable manufacturing.

  3. Toward glycerol biorefinery: metabolic engineering for the production of biofuels and chemicals from glycerol.

    PubMed

    Chen, Zhen; Liu, Dehua

    2016-01-01

    As an inevitable by-product of the biofuel industry, glycerol is becoming an attractive feedstock for biorefinery due to its abundance, low price and high degree of reduction. Converting crude glycerol into value-added products is important to increase the economic viability of the biofuel industry. Metabolic engineering of industrial strains to improve its performance and to enlarge the product spectrum of glycerol biotransformation process is highly important toward glycerol biorefinery. This review focuses on recent metabolic engineering efforts as well as challenges involved in the utilization of glycerol as feedstock for the production of fuels and chemicals, especially for the production of diols, organic acids and biofuels.

  4. Aquatic plant Azolla as the universal feedstock for biofuel production.

    PubMed

    Miranda, Ana F; Biswas, Bijoy; Ramkumar, Narasimhan; Singh, Rawel; Kumar, Jitendra; James, Anton; Roddick, Felicity; Lal, Banwari; Subudhi, Sanjukta; Bhaskar, Thallada; Mouradov, Aidyn

    2016-01-01

    The quest for sustainable production of renewable and cheap biofuels has triggered an intensive search for domestication of the next generation of bioenergy crops. Aquatic plants which can rapidly colonize wetlands are attracting attention because of their ability to grow in wastewaters and produce large amounts of biomass. Representatives of Azolla species are some of the fastest growing plants, producing substantial biomass when growing in contaminated water and natural ecosystems. Together with their evolutional symbiont, the cyanobacterium Anabaena azollae, Azolla biomass has a unique chemical composition accumulating in each leaf including three major types of bioenergy molecules: cellulose/hemicellulose, starch and lipids, resembling combinations of terrestrial bioenergy crops and microalgae. The growth of Azolla filiculoides in synthetic wastewater led up to 25, 69, 24 and 40 % reduction of NH4-N, NO3-N, PO4-P and selenium, respectively, after 5 days of treatment. This led to a 2.6-fold reduction in toxicity of the treated wastewater to shrimps, common inhabitants of wetlands. Two Azolla species, Azolla filiculoides and Azolla pinnata, were used as feedstock for the production of a range of functional hydrocarbons through hydrothermal liquefaction, bio-hydrogen and bio-ethanol. Given the high annual productivity of Azolla, hydrothermal liquefaction can lead to the theoretical production of 20.2 t/ha-year of bio-oil and 48 t/ha-year of bio-char. The ethanol production from Azolla filiculoides, 11.7 × 10(3) L/ha-year, is close to that from corn stover (13.3 × 10(3) L/ha-year), but higher than from miscanthus (2.3 × 10(3) L/ha-year) and woody plants, such as willow (0.3 × 10(3) L/ha-year) and poplar (1.3 × 10(3) L/ha-year). With a high C/N ratio, fermentation of Azolla biomass generates 2.2 mol/mol glucose/xylose of hydrogen, making this species a competitive feedstock for hydrogen production compared with other bioenergy crops. The

  5. BioFuelDB: a database and prediction server of enzymes involved in biofuels production

    PubMed Central

    Gupta, Sudheer

    2017-01-01

    Background In light of the rapid decrease in fossils fuel reserves and an increasing demand for energy, novel methods are required to explore alternative biofuel production processes to alleviate these pressures. A wide variety of molecules which can either be used as biofuels or as biofuel precursors are produced using microbial enzymes. However, the common challenges in the industrial implementation of enzyme catalysis for biofuel production are the unavailability of a comprehensive biofuel enzyme resource, low efficiency of known enzymes, and limited availability of enzymes which can function under extreme conditions in the industrial processes. Methods We have developed a comprehensive database of known enzymes with proven or potential applications in biofuel production through text mining of PubMed abstracts and other publicly available information. A total of 131 enzymes with a role in biofuel production were identified and classified into six enzyme classes and four broad application categories namely ‘Alcohol production’, ‘Biodiesel production’, ‘Fuel Cell’ and ‘Alternate biofuels’. A prediction tool ‘Benz’ was developed to identify and classify novel homologues of the known biofuel enzyme sequences from sequenced genomes and metagenomes. ‘Benz’ employs a hybrid approach incorporating HMMER 3.0 and RAPSearch2 programs to provide high accuracy and high speed for prediction. Results Using the Benz tool, 153,754 novel homologues of biofuel enzymes were identified from 23 diverse metagenomic sources. The comprehensive data of curated biofuel enzymes, their novel homologs identified from diverse metagenomes, and the hybrid prediction tool Benz are presented as a web server which can be used for the prediction of biofuel enzymes from genomic and metagenomic datasets. The database and the Benz tool is publicly available at http://metabiosys.iiserb.ac.in/biofueldb& http://metagenomics.iiserb.ac.in/biofueldb. PMID:28875065

  6. 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.

  7. Processing of cellulose for the advancement of biofuels

    NASA Astrophysics Data System (ADS)

    Watson, Brian James

    2011-12-01

    The enzymatic degradation of cellulose polymers is currently a rate-limiting step in the bioconversion of biomass to biofuels. Cellulose polymers self assemble to form crystalline structures stabilized by a complex network of intermolecular interactions such as hydrogen bonding. The network of interactions in crystalline cellulose (cellulose nanostructure) poses an energy barrier that limits enzymatic degradation as apparent from the activity of Cel5H. To improve the degradability of cellulose the intermolecular interactions must be disrupted. The interactions of the cellulose nanostructure prevent solubilization by water and most other common solvents, but some organic solvents aid degradation of cellulose suggesting they influence cellulose nanostructure. The objective of this work is to understand the influence of solvents on cellulose nanostructure with the goal of improving the degradability of cellulose nanostructure using solvents. To understand solvent interaction with cellulose, phosphoric acid was used to first solubilize cellulose (PAS cellulose) followed by adding an organic liquid or water to wash the phosphate from the system. The Flory Huggins theory was used to predict wash liquids that could favorably interact with cellulose. A favorable wash liquid was predicted to prevent the reformation of crystalline domains to yield a disrupted cellulose nanostructure, which should be more degradable. Low molecular weight alcohols and glycols were calculated to be favorable wash liquids. Washing PAS cellulose with the predicted favorable liquids yielded semi-transparent gel-like materials compared to the opaque white precipitate formed when water or unfavorable solvents were used in the wash. Fractal analysis of small angle neutron scattering (SANS) of these apparent gels indicated cellulose polymers likely have the properties of clustered rods. This partial disruption increased degradability relative to the water washed PAS cellulose. The apparent rod

  8. 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.

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

    USDA-ARS?s Scientific Manuscript database

    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....

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

    DOE PAGES

    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

  11. 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.

  12. 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

  13. "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

  14. 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

  15. 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

    2012-10-07

    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.

  16. Innovation in biological production and upgrading of methane and hydrogen for use as gaseous transport biofuel.

    PubMed

    Xia, Ao; Cheng, Jun; Murphy, Jerry D

    2016-01-01

    Biofuels derived from biomass will play a major role in future renewable energy supplies in transport. Gaseous biofuels have superior energy balances, offer greater greenhouse gas emission reductions and produce lower pollutant emissions than liquid biofuels. Biogas derived through fermentation of wet organic substrates will play a major role in future transport systems. Biogas (which is composed of approximately 60% methane/hydrogen and 40% carbon dioxide) requires an upgrading process to reduce the carbon dioxide content to less than 3% before it is used as compressed gas in transport. This paper reviews recent developments in fermentative biogas production and upgrading as a transport fuel. Third generation gaseous biofuels may be generated using marine-based algae via two-stage fermentation, cogenerating hydrogen and methane. Alternative biological upgrading techniques, such as biological methanation and microalgal biogas upgrading, have the potential to simultaneously upgrade biogas, increase gaseous biofuel yield and reduce carbon dioxide emission.

  17. 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

    2015-07-07

    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.

  18. Dynamic Modeling of Learning in Emerging Energy Industries: The Example of Advanced Biofuels in the United States; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Peterson, Steve; Bush, Brian; Vimmerstedt, Laura

    2015-07-19

    This paper (and its supplemental model) presents novel approaches to modeling interactions and related policies among investment, production, and learning in an emerging competitive industry. New biomass-to-biofuels pathways are being developed and commercialized to support goals for U.S. advanced biofuel use, such as those in the Energy Independence and Security Act of 2007. We explore the impact of learning rates and techno-economics in a learning model excerpted from the Biomass Scenario Model (BSM), developed by the U.S. Department of Energy and the National Renewable Energy Laboratory to explore the impact of biofuel policy on the evolution of the biofuels industry. The BSM integrates investment, production, and learning among competing biofuel conversion options that are at different stages of industrial development. We explain the novel methods used to simulate the impact of differing assumptions about mature industry techno-economics and about learning rates while accounting for the different maturity levels of various conversion pathways. A sensitivity study shows that the parameters studied (fixed capital investment, process yield, progress ratios, and pre-commercial investment) exhibit highly interactive effects, and the system, as modeled, tends toward market dominance of a single pathway due to competition and learning dynamics.

  19. 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)...

  20. 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)...

  1. Final Technical Report - Use of Systems Biology Approaches to Develop Advanced Biofuel-Synthesizing Cyanobacterial Strains

    SciTech Connect

    Pakrasi, Himadri

    2016-09-01

    The overall objective of this project was to use a systems biology approach to evaluate the potentials of a number of cyanobacterial strains for photobiological production of advanced biofuels and/or their chemical precursors. Cyanobacteria are oxygen evolving photosynthetic prokaryotes. Among them, certain unicellular species such as Cyanothece can also fix N2, a process that is exquisitely sensitive to oxygen. To accommodate such incompatible processes in a single cell, Cyanothece produces oxygen during the day, and creates an O2-limited intracellular environment during the night to perform O2-sensitive processes such as N2-fixation. Thus, Cyanothece cells are natural bioreactors for the storage of captured solar energy with subsequent utilization at a different time during a diurnal cycle. Our studies include the identification of a novel, fast-growing, mixotrophic, transformable cyanobacterium. This strain has been sequenced and will be made available to the community. In addition, we have developed genome-scale models for a family of cyanobacteria to assess their metabolic repertoire. Furthermore, we developed a method for rapid construction of metabolic models using multiple annotation sources and a metabolic model of a related organism. This method will allow rapid annotation and screening of potential phenotypes based on the newly available genome sequences of many organisms.

  2. Use of proteomic tools in microbial engineering for biofuel production.

    PubMed

    Mao, Shaoming; Jia, Kaizhi; Zhang, Yanping; Li, Yin

    2012-01-01

    The production of biofuels from renewable sources by microbial engineering has gained increased attention due to energy and environmental concerns. Butanol is one of the important gasoline-substitute fuels and can be produced by native microorganism Clostridium acetobutylicum. To develop a fundamental tool to understand C. acetobutylicum, a high resolution proteome reference map for this species has been established. To better understand the relationship between butanol tolerance and butanol yield, we performed a comparative proteomic analysis between the wild-type strain DSM 1731 and its mutant Rh8 at acidogenic and solventogenic phases, respectively. The 102 differentially expressed proteins that are mainly involved in protein folding, solvent formation, amino acid metabolism, protein synthesis, nucleotide metabolism, transport, and others were detected. Hierarchical clustering analysis revealed that over 70% of the 102 differentially expressed proteins in mutant Rh8 were either upregulated (e.g., chaperones and solvent formation related) or downregulated (e.g., amino acid metabolism and protein synthesis related) in both acidogenic and solventogenic phase, which, respectively, are only upregulated or downregulated in solventogenic phase in the wild-type strain.

  3. 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.

  4. 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.

  5. Recent progress and future challenges in algal biofuel production

    PubMed Central

    Shurin, Jonathan B.; Burkart, Michael D.; Mayfield, Stephen P.

    2016-01-01

    Modern society is fueled by fossil energy produced millions of years ago by photosynthetic organisms. Cultivating contemporary photosynthetic producers to generate energy and capture carbon from the atmosphere is one potential approach to sustaining society without disrupting the climate. Algae, photosynthetic aquatic microorganisms, are the fastest growing primary producers in the world and can therefore produce more energy with less land, water, and nutrients than terrestrial plant crops. We review recent progress and challenges in developing bioenergy technology based on algae. A variety of high-value products in addition to biofuels can be harvested from algal biomass, and these may be key to developing algal biotechnology and realizing the commercial potential of these organisms. Aspects of algal biology that differentiate them from plants demand an integrative approach based on genetics, cell biology, ecology, and evolution. We call for a systems approach to research on algal biotechnology rooted in understanding their biology, from the level of genes to ecosystems, and integrating perspectives from physical, chemical, and social sciences to solve one of the most critical outstanding technological problems. PMID:27781084

  6. Membranes with artificial free-volume for biofuel production

    DOE PAGES

    Petzetakis, Nikos; Doherty, Cara M.; Thornton, Aaron W.; ...

    2015-06-24

    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. Here, we have used this method to fabricate a series of membranes with identical compositions but with different amounts of free-volume. We use the termmore » 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. Moreover, we found that the introduction of artificial free-volume improves both alcohol permeability and selectivity.« less

  7. Membranes with artificial free-volume for biofuel production

    SciTech Connect

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

    2015-06-24

    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. Here, 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. Moreover, we found that the introduction of artificial free-volume improves both alcohol permeability and selectivity.

  8. 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.

  9. 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

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

    SciTech Connect

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

    2014-12-02

    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. Furthermore, energy conservation and identifying and effectively protecting habitats with high-conservation value are critical first steps toward protecting biodiversity under any fuel production scenario.

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

    DOE PAGES

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

    2014-12-02

    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. Furthermore, 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

  12. Estimation of economic impacts of cellulosic biofuel production: a comparative analysis of three biofuel pathways

    SciTech Connect

    Zhang, Yimin; Goldberg, Marshall; Tan, Eric; Meyer, Pimphan Aye

    2016-03-07

    The development of a cellulosic biofuel industry utilizing domestic biomass resources is expected to create opportunities for economic growth resulting from the construction and operation of new biorefineries. We applied an economic input-output model to estimate potential economic impacts, particularly gross job growth, resulting from the construction and operation of biorefineries using three different technology pathways: (i) cellulosic ethanol via biochemical conversion in Iowa, (ii) renewable diesel blendstock via biological conversion in Georgia, and (iii) renewable diesel and gasoline blendstock via fast pyrolysis in Mississippi. Combining direct, indirect (revenue- and supply-chain-related), and induced effects, capital investment associated with the construction of a biorefinery processing 2000 dry metric tons of biomass per day (DMT/day) could yield between 5960 and 8470 full-time equivalent (FTE) jobs during the construction period, depending on the biofuel pathways. Fast pyrolysis biorefineries produce the most jobs on a project level thanks to the highest capital requirement among the three pathways. Normalized on the scale of $1 million of capital investment, the fast pyrolysis biorefineries are estimated to yield slighter higher numbers of jobs (12.1 jobs) than the renewable diesel (11.8 jobs) and the cellulosic ethanol (11.6 jobs) biorefineries. While operating biorefineries is not labor-intensive, the annual operation of a 2000 DMT/day biorefinery could support between 720 and 970 jobs when the direct, indirect, and induced effects are considered. The major factor, which results in the variations among the three pathways, is the type of biomass feedstock used for biofuels. Unlike construction jobs, these operation-related jobs are necessary over the entire life of the biorefineries. In conclusion, our results show that indirect effects stimulated by the operation of biorefineries are the primary contributor to job growth. The agriculture

  13. Estimation of economic impacts of cellulosic biofuel production: a comparative analysis of three biofuel pathways

    DOE PAGES

    Zhang, Yimin; Goldberg, Marshall; Tan, Eric; ...

    2016-03-07

    The development of a cellulosic biofuel industry utilizing domestic biomass resources is expected to create opportunities for economic growth resulting from the construction and operation of new biorefineries. We applied an economic input-output model to estimate potential economic impacts, particularly gross job growth, resulting from the construction and operation of biorefineries using three different technology pathways: (i) cellulosic ethanol via biochemical conversion in Iowa, (ii) renewable diesel blendstock via biological conversion in Georgia, and (iii) renewable diesel and gasoline blendstock via fast pyrolysis in Mississippi. Combining direct, indirect (revenue- and supply-chain-related), and induced effects, capital investment associated with the constructionmore » of a biorefinery processing 2000 dry metric tons of biomass per day (DMT/day) could yield between 5960 and 8470 full-time equivalent (FTE) jobs during the construction period, depending on the biofuel pathways. Fast pyrolysis biorefineries produce the most jobs on a project level thanks to the highest capital requirement among the three pathways. Normalized on the scale of $1 million of capital investment, the fast pyrolysis biorefineries are estimated to yield slighter higher numbers of jobs (12.1 jobs) than the renewable diesel (11.8 jobs) and the cellulosic ethanol (11.6 jobs) biorefineries. While operating biorefineries is not labor-intensive, the annual operation of a 2000 DMT/day biorefinery could support between 720 and 970 jobs when the direct, indirect, and induced effects are considered. The major factor, which results in the variations among the three pathways, is the type of biomass feedstock used for biofuels. Unlike construction jobs, these operation-related jobs are necessary over the entire life of the biorefineries. In conclusion, our results show that indirect effects stimulated by the operation of biorefineries are the primary contributor to job growth. The agriculture

  14. Estimation of Economic Impacts of Cellulosic Biofuel Production: A Comparative Analysis of Three Biofuel Pathways

    SciTech Connect

    Zhang, Yimin; Goldberg, Marshall; Tan, Eric; Meyer, Pimphan Aye

    2016-05-01

    The development of a cellulosic biofuel industry utilizing domestic biomass resources is expected to create opportunities for economic growth resulting from the construction and operation of new biorefineries. We applied an economic input-output model to estimate potential economic impacts, particularly gross job growth, resulting from the construction and operation of biorefineries using three different technology pathways: (i) cellulosic ethanol via biochemical conversion in Iowa, (ii) renewable diesel blendstock via biological conversion in Georgia, and (iii) renewable diesel and gasoline blendstock via fast pyrolysis in Mississippi. Combining direct, indirect (revenue- and supply-chain-related), and induced effects, capital investment associated with the construction of a biorefinery processing 2000 dry metric tons of biomass per day (DMT/day) could yield between 5960 and 8470 full-time equivalent (FTE) jobs during the construction period, depending on the biofuel pathways. Fast pyrolysis biorefineries produce the most jobs on a project level thanks to the highest capital requirement among the three pathways. Normalized on the scale of $1 million of capital investment, the fast pyrolysis biorefineries are estimated to yield slighter higher numbers of jobs (12.1 jobs) than the renewable diesel (11.8 jobs) and the cellulosic ethanol (11.6 jobs) biorefineries. While operating biorefineries is not labor-intensive, the annual operation of a 2000 DMT/day biorefinery could support between 720 and 970 jobs when the direct, indirect, and induced effects are considered. The major factor, which results in the variations among the three pathways, is the type of biomass feedstock used for biofuels. Unlike construction jobs, these operation-related jobs are necessary over the entire life of the biorefineries. Our results show that indirect effects stimulated by the operation of biorefineries are the primary contributor to job growth. The agriculture/forest, services, and

  15. 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.

  16. 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.

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

    PubMed

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

    2015-01-01

    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

  18. Intentions of UK farmers toward biofuel crop production: implications for policy targets and land use change.

    PubMed

    Mattison, Elizabeth H A; Norris, Ken

    2007-08-15

    The United States and the European Union have set targets for biofuel production to decrease reliance on fossil fuels and to reduce fossil carbon emissions. Attainment of biofuel targets depends upon policy and infrastructure development but also on production of suitable raw materials. Production of relevant crops relies on the decisions that farmers make in their economic and political environment. We need to identify any farmer-related barriers to biofuel production and to determine whether novel policy and technology are required to meet targets. These aspects of the emerging biofuel industry are relevant across international barriers and have not yet been addressed quantitatively. We describe a case study from the UK of farmers' intentions toward producing two biofuel crops for which refining capacity either exists or is under construction. Given farmers' intentions, current land use, and conversion efficiency, we estimate potential biofuel production. These estimates indicate that EU targets are not achievable using domestically grown raw materials without policy intervention, use of alternative feedstocks, and either significant improvements in processing efficiency or large-scale changes in land use.

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

    PubMed Central

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

    2017-01-01

    SUMMARY 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

  20. 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. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  1. 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.

  2. 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.

  3. One-pot bioconversion of algae biomass into terpenes for advanced biofuels and bioproducts

    SciTech Connect

    Davis, Ryan Wesley; Wu, Weihua

    2016-01-01

    In this study, rising demand for transportation fuels, diminishing reserved of fossil oil, and the concerns with fossil fuel derived environmental pollution as well as the green-house gas emission derived climate change have resulted in the compelling need for alternative, sustainable new energy sources(1). Algae-based biofuels have been considered one of the promising alternatives to fossil fuels as they can overcome some of these issues (2-4). The current state-of-art of algal biofuel technologies have primarily focused on biodiesel production through prompting high algal lipid yields under the nutrient stress conditions. There are less interests of using algae-based carbohydrate and proteins as carbon sources for the fermentative production of liquid fuel compounds or other high-value bioproducts(5-7).

  4. One-pot bioconversion of algae biomass into terpenes for advanced biofuels and bioproducts

    DOE PAGES

    Davis, Ryan Wesley; Wu, Weihua

    2016-01-01

    In this study, rising demand for transportation fuels, diminishing reserved of fossil oil, and the concerns with fossil fuel derived environmental pollution as well as the green-house gas emission derived climate change have resulted in the compelling need for alternative, sustainable new energy sources(1). Algae-based biofuels have been considered one of the promising alternatives to fossil fuels as they can overcome some of these issues (2-4). The current state-of-art of algal biofuel technologies have primarily focused on biodiesel production through prompting high algal lipid yields under the nutrient stress conditions. There are less interests of using algae-based carbohydrate and proteinsmore » as carbon sources for the fermentative production of liquid fuel compounds or other high-value bioproducts(5-7).« less

  5. 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.

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

    Treesearch

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

    2015-01-01

    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...

  7. 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

  8. 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.

  9. Present and potential future oilseed production systems for biofuels

    USDA-ARS?s Scientific Manuscript database

    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...

  10. 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…

  11. 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…

  12. Biofuels, fossil energy ratio, and the future of energy production

    NASA Astrophysics Data System (ADS)

    Consiglio, David

    2017-05-01

    Two hundred years ago, much of humanity's energy came from burning wood. As energy needs outstripped supplies, we began to burn fossil fuels. This transition allowed our civilization to modernize rapidly, but it came with heavy costs including climate change. Today, scientists and engineers are taking another look at biofuels as a source of energy to fuel our ever-increasing consumption.

  13. Unraveling water quality and quantity effects of biofuels production

    USDA-ARS?s Scientific Manuscript database

    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 ...

  14. 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.

  15. A Techno-Economic Analysis of Emission Controls on Hydrocarbon Biofuel Production

    SciTech Connect

    Bhatt, Arpit; Zhang, Yimin; Davis, Ryan; Eberle, Annika; Heath, Garvin

    2016-06-23

    Biofuels have the potential to reduce our dependency on petroleum-derived transportation fuels and decrease greenhouse gas (GHG) emissions. Although the overall GHG emissions from biofuels are expected to be lower when compared to those of petroleum fuels, the process of converting biomass feedstocks into biofuels emits various air pollutants, which may be subject to federal air quality regulation or emission limits. While prior research has evaluated the technical and economic feasibility of biofuel technologies, gaps still exist in understanding the regulatory issues associated with the biorefineries and their economic implications on biofuel production costs (referred to as minimum fuel selling price (MFSP) in this study). The aim of our research is to evaluate the economic impact of implementing emission reduction technologies at biorefineries and estimate the cost effectiveness of two primary control technologies that may be required for air permitting purposes. We analyze a lignocellulosic sugars-to-hydrocarbon biofuel production pathway developed by the National Renewable Energy Laboratory (NREL) and implement air emission controls in Aspen Plus to evaluate how they affect the MFSP. Results from this analysis can help inform decisions about biorefinery siting and sizing, as well as mitigate the risks associated with air permitting.

  16. Techno-economic and Monte Carlo probabilistic analysis of microalgae biofuel production system.

    PubMed

    Batan, Liaw Y; Graff, Gregory D; Bradley, Thomas H

    2016-11-01

    This study focuses on the characterization of the technical and economic feasibility of an enclosed photobioreactor microalgae system with annual production of 37.85 million liters (10 million gallons) of biofuel. The analysis characterizes and breaks down the capital investment and operating costs and the production cost of unit of algal diesel. The economic modelling shows total cost of production of algal raw oil and diesel of $3.46 and $3.69 per liter, respectively. Additionally, the effects of co-products' credit and their impact in the economic performance of algal-to-biofuel system are discussed. The Monte Carlo methodology is used to address price and cost projections and to simulate scenarios with probabilities of financial performance and profits of the analyzed model. Different markets for allocation of co-products have shown significant shifts for economic viability of algal biofuel system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Interactions of Woody Biofuel Feedstock Production Systems with Water Resources: Considerations for Sustainability

    SciTech Connect

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

    2008-04-15

    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. Finally, 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.

  18. Biofuel production from palm oil with supercritical alcohols: effects of the alcohol to oil molar ratios on the biofuel chemical composition and properties.

    PubMed

    Sawangkeaw, Ruengwit; Teeravitud, Sunsanee; Bunyakiat, Kunchana; Ngamprasertsith, Somkiat

    2011-11-01

    Biofuel production from palm oil with supercritical methanol (SCM) and supercritical ethanol (SCE) at 400 °C and 15 MPa were evaluated. At the optimal alcohol to oil molar ratios of 12:1 and 18:1 for the SCM and SCE processes, respectively, the biofuel samples were synthesized in a 1.2-L reactor and the resulting biofuel was analyzed for the key properties including those for the diesel and biodiesel standard specifications. Biofuel samples derived from both the SCM and SCE processes could be used as an alternative fuel after slight improvement in their acid value and free glycerol content. The remarkable advantages of this novel process were: the additional fuel yield of approximately of 5% and 10% for SCM and SCE, respectively; the lower energy consumption for alcohol preheating, pumping and recovering than the biodiesel production with supercritical alcohols that use a high alcohol to oil molar ratio of 42:1.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Large-scale production of diesel-like biofuels - process design as an inherent part of microorganism development.

    PubMed

    Cuellar, Maria C; Heijnen, Joseph J; van der Wielen, Luuk A M

    2013-06-01

    Industrial biotechnology is playing an important role in the transition to a bio-based economy. Currently, however, industrial implementation is still modest, despite the advances made in microorganism development. Given that the fuels and commodity chemicals sectors are characterized by tight economic margins, we propose to address overall process design and efficiency at the start of bioprocess development. While current microorganism development is targeted at product formation and product yield, addressing process design at the start of bioprocess development means that microorganism selection can also be extended to other critical targets for process technology and process scale implementation, such as enhancing cell separation or increasing cell robustness at operating conditions that favor the overall process. In this paper we follow this approach for the microbial production of diesel-like biofuels. We review current microbial routes with both oleaginous and engineered microorganisms. For the routes leading to extracellular production, we identify the process conditions for large scale operation. The process conditions identified are finally translated to microorganism development targets. We show that microorganism development should be directed at anaerobic production, increasing robustness at extreme process conditions and tailoring cell surface properties. All the same time, novel process configurations integrating fermentation and product recovery, cell reuse and low-cost technologies for product separation are mandatory. This review provides a state-of-the-art summary of the latest challenges in large-scale production of diesel-like biofuels.

  4. 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

  5. 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.

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

    Treesearch

    Carl C. Trettin; Devendra Amatya; Mark Coleman

    2008-01-01

    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...

  7. Interactions of woody biofuel feedstock production systems with water resources: considerations for sustainability

    Treesearch

    Carl C. Trettin; Devendra Amatya; Mark Coleman

    2008-01-01

    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...

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

    USDA-ARS?s Scientific Manuscript database

    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...

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

    DOE PAGES

    Tang, Xiaoyu; da Costa Sousa, Leonardo; Jin, Mingjie; ...

    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

  10. 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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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) (σ=60), 3 times more methane than was produced by the LEA, 140 cm(3)-CH4 g-VS(-1) (σ=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.

  16. Salinity induced oxidative stress enhanced biofuel production potential of microalgae Scenedesmus sp. CCNM 1077.

    PubMed

    Pancha, Imran; Chokshi, Kaumeel; Maurya, Rahulkumar; Trivedi, Khanjan; Patidar, Shailesh Kumar; Ghosh, Arup; Mishra, Sandhya

    2015-01-01

    Microalgal biomass is considered as potential feedstock for biofuel production. Enhancement of biomass, lipid and carbohydrate contents in microalgae is important for the commercialization of microalgal biofuels. In the present study, salinity stress induced physiological and biochemical changes in microalgae Scenedesmus sp. CCNM 1077 were studied. During single stage cultivation, 33.13% lipid and 35.91% carbohydrate content was found in 400 mM NaCl grown culture. During two stage cultivation, salinity stress of 400 mM for 3 days resulted in 24.77% lipid (containing 74.87% neutral lipid) along with higher biomass compared to single stage, making it an efficient strategy to enhance biofuel production potential of Scenedesmus sp. CCNM 1077. Apart from biochemical content, stress biomarkers like hydrogen peroxide, lipid peroxidation, ascorbate peroxidase, proline and mineral contents were also studied to understand the role of reactive oxygen species (ROS) mediated lipid accumulation in microalgae Scenedesmus sp. CCNM 1077.

  17. 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.

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

    PubMed

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

    2016-04-01

    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.

  19. Metabolic and process engineering of Clostridium cellulovorans for biofuel production from cellulose.

    PubMed

    Yang, Xiaorui; Xu, Mengmeng; Yang, Shang-Tian

    2015-11-01

    Production of cellulosic biofuels has drawn increasing attention. However, currently no microorganism can produce biofuels, particularly butanol, directly from cellulosic biomass efficiently. Here we engineered a cellulolytic bacterium, Clostridium cellulovorans, for n-butanol and ethanol production directly from cellulose by introducing an aldehyde/alcohol dehydrogenase (adhE2), which converts butyryl-CoA to n-butanol and acetyl-CoA to ethanol. The engineered strain was able to produce 1.42 g/L n-butanol and 1.60 g/L ethanol directly from cellulose. Moreover, the addition of methyl viologen as an artificial electron carrier shifted the metabolic flux from acid production to alcohol production, resulting in a high biofuel yield of 0.39 g/g from cellulose, comparable to ethanol yield from corn dextrose by yeast fermentation. This study is the first metabolic engineering of C. cellulovorans for n-butanol and ethanol production directly from cellulose with significant titers and yields, providing a promising consolidated bioprocessing (CBP) platform for biofuel production from cellulosic biomass.

  20. A Thermophilic Ionic Liquid-Tolerant Cellulase Cocktail for the Production of Cellulosic Biofuels

    PubMed Central

    Park, Joshua I.; Steen, Eric J.; Burd, Helcio; Evans, Sophia S.; Redding-Johnson, Alyssa M.; Batth, Tanveer; Benke, Peter I.; D'haeseleer, Patrik; Sun, Ning; Sale, Kenneth L.; Keasling, Jay D.; Lee, Taek Soon; Petzold, Christopher J.; Mukhopadhyay, Aindrila; Singer, Steven W.; Simmons, Blake A.; Gladden, John M.

    2012-01-01

    Generation of biofuels from sugars in lignocellulosic biomass is a promising alternative to liquid fossil fuels, but efficient and inexpensive bioprocessing configurations must be developed to make this technology commercially viable. One of the major barriers to commercialization is the recalcitrance of plant cell wall polysaccharides to enzymatic hydrolysis. Biomass pretreatment with ionic liquids (ILs) enables efficient saccharification of biomass, but residual ILs inhibit both saccharification and microbial fuel production, requiring extensive washing after IL pretreatment. Pretreatment itself can also produce biomass-derived inhibitory compounds that reduce microbial fuel production. Therefore, there are multiple points in the process from biomass to biofuel production that must be interrogated and optimized to maximize fuel production. Here, we report the development of an IL-tolerant cellulase cocktail by combining thermophilic bacterial glycoside hydrolases produced by a mixed consortia with recombinant glycoside hydrolases. This enzymatic cocktail saccharifies IL-pretreated biomass at higher temperatures and in the presence of much higher IL concentrations than commercial fungal cocktails. Sugars obtained from saccharification of IL-pretreated switchgrass using this cocktail can be converted into biodiesel (fatty acid ethyl-esters or FAEEs) by a metabolically engineered strain of E. coli. During these studies, we found that this biodiesel-producing E. coli strain was sensitive to ILs and inhibitors released by saccharification. This cocktail will enable the development of novel biomass to biofuel bioprocessing configurations that may overcome some of the barriers to production of inexpensive cellulosic biofuels. PMID:22649505

  1. A thermophilic ionic liquid-tolerant cellulase cocktail for the production of cellulosic biofuels.

    PubMed

    Park, Joshua I; Steen, Eric J; Burd, Helcio; Evans, Sophia S; Redding-Johnson, Alyssa M; Batth, Tanveer; Benke, Peter I; D'haeseleer, Patrik; Sun, Ning; Sale, Kenneth L; Keasling, Jay D; Lee, Taek Soon; Petzold, Christopher J; Mukhopadhyay, Aindrila; Singer, Steven W; Simmons, Blake A; Gladden, John M

    2012-01-01

    Generation of biofuels from sugars in lignocellulosic biomass is a promising alternative to liquid fossil fuels, but efficient and inexpensive bioprocessing configurations must be developed to make this technology commercially viable. One of the major barriers to commercialization is the recalcitrance of plant cell wall polysaccharides to enzymatic hydrolysis. Biomass pretreatment with ionic liquids (ILs) enables efficient saccharification of biomass, but residual ILs inhibit both saccharification and microbial fuel production, requiring extensive washing after IL pretreatment. Pretreatment itself can also produce biomass-derived inhibitory compounds that reduce microbial fuel production. Therefore, there are multiple points in the process from biomass to biofuel production that must be interrogated and optimized to maximize fuel production. Here, we report the development of an IL-tolerant cellulase cocktail by combining thermophilic bacterial glycoside hydrolases produced by a mixed consortia with recombinant glycoside hydrolases. This enzymatic cocktail saccharifies IL-pretreated biomass at higher temperatures and in the presence of much higher IL concentrations than commercial fungal cocktails. Sugars obtained from saccharification of IL-pretreated switchgrass using this cocktail can be converted into biodiesel (fatty acid ethyl-esters or FAEEs) by a metabolically engineered strain of E. coli. During these studies, we found that this biodiesel-producing E. coli strain was sensitive to ILs and inhibitors released by saccharification. This cocktail will enable the development of novel biomass to biofuel bioprocessing configurations that may overcome some of the barriers to production of inexpensive cellulosic biofuels.

  2. Evaluating the relative impacts of operational and financial factors on the competitiveness of an algal biofuel production facility.

    PubMed

    Hise, Adam M; Characklis, Gregory W; Kern, Jordan; Gerlach, Robin; Viamajala, Sridhar; Gardner, Robert D; Vadlamani, Agasteswar

    2016-11-01

    Algal biofuels are becoming more economically competitive due to technological advances and government subsidies offering tax benefits and lower cost financing. These factors are linked, however, as the value of technical advances is affected by modeling assumptions regarding the growth conditions, process design, and financing of the production facility into which novel techniques are incorporated. Two such techniques, related to algal growth and dewatering, are evaluated in representative operating and financing scenarios using an integrated techno-economic model. Results suggest that these techniques can be valuable under specified conditions, but also that investment subsidies influence cost competitive facility design by incentivizing development of more capital intensive facilities (e.g., favoring hydrothermal liquefaction over transesterification-based facilities). Evaluating novel techniques under a variety of operational and financial scenarios highlights the set of site-specific conditions in which technical advances are most valuable, while also demonstrating the influence of subsidies linked to capital intensity.

  3. 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

  4. Biofuels from food processing wastes.

    PubMed

    Zhang, Zhanying; O'Hara, Ian M; Mundree, Sagadevan; Gao, Baoyu; Ball, Andrew S; Zhu, Nanwen; Bai, Zhihui; Jin, Bo

    2016-04-01

    Food processing industry generates substantial high organic wastes along with high energy uses. The recovery of food processing wastes as renewable energy sources represents a sustainable option for the substitution of fossil energy, contributing to the transition of food sector towards a low-carbon economy. This article reviews the latest research progress on biofuel production using food processing wastes. While extensive work on laboratory and pilot-scale biosystems for energy production has been reported, this work presents a review of advances in metabolic pathways, key technical issues and bioengineering outcomes in biofuel production from food processing wastes. Research challenges and further prospects associated with the knowledge advances and technology development of biofuel production are discussed.

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

    USDA-ARS?s Scientific Manuscript database

    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...

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

    USDA-ARS?s Scientific Manuscript database

    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....

  7. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  9. 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.

  10. Estimating Sugarcane Water Requirements for Biofuel Feedstock Production in Maui, Hawaii Using Satellite Imagery

    USDA-ARS?s Scientific Manuscript database

    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...

  11. Soil water infiltration affected by biofuel and grain crop production systems in claypan landscape

    USDA-ARS?s Scientific Manuscript database

    The effect of soil management systems on water infiltration is very crucial within claypan landscapes to maximize production as well as minimize environmental risks. The objective of this study was to assess the effect of topsoil thickness on water infiltration in claypan soils for grain and biofuel...

  12. 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.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  14. Environmental and resource burdens associated with world biofuel production out to 2050: footprint components from carbon emissions and land use to waste arisings and water consumption.

    PubMed

    Hammond, Geoffrey P; Li, Bo

    2016-09-01

    Environmental or 'ecological' footprints have been widely used in recent years as indicators of resource consumption and waste absorption presented in terms of biologically productive land area [in global hectares (gha)] required per capita with prevailing technology. In contrast, 'carbon footprints' are the amount of carbon (or carbon dioxide equivalent) emissions for such activities in units of mass or weight (like kilograms per functional unit), but can be translated into a component of the environmental footprint (on a gha basis). The carbon and environmental footprints associated with the world production of liquid biofuels have been computed for the period 2010-2050. Estimates of future global biofuel production were adopted from the 2011 International Energy Agency (IEA) 'technology roadmap' for transport biofuels. This suggests that, although first generation biofuels will dominate the market up to 2020, advanced or second generation biofuels might constitute some 75% of biofuel production by 2050. The overall environmental footprint was estimated to be 0.29 billion (bn) gha in 2010 and is likely to grow to around 2.57 bn gha by 2050. It was then disaggregated into various components: bioproductive land, built land, carbon emissions, embodied energy, materials and waste, transport, and water consumption. This component-based approach has enabled the examination of the Manufactured and Natural Capital elements of the 'four capitals' model of sustainability quite broadly, along with specific issues (such as the linkages associated with the so-called energy-land-water nexus). Bioproductive land use was found to exhibit the largest footprint component (a 48% share in 2050), followed by the carbon footprint (23%), embodied energy (16%), and then the water footprint (9%). Footprint components related to built land, transport and waste arisings were all found to account for an insignificant proportion to the overall environmental footprint, together amounting to

  15. Life cycle assessment of biofuel production from brown seaweed in Nordic conditions.

    PubMed

    Alvarado-Morales, Merlin; Boldrin, Alessio; Karakashev, Dimitar B; Holdt, Susan L; Angelidaki, Irini; Astrup, Thomas

    2013-02-01

    The use of algae for biofuel production is expected to play an important role in securing energy supply in the next decades. A consequential life cycle assessment (LCA) and an energy analysis of seaweed-based biofuel production were carried out in Nordic conditions to document and improve the sustainability of the process. Two scenarios were analyzed for the brown seaweed (Laminaria digitata), namely, biogas production (scenario 1) and bioethanol+biogas production (scenario 2). Potential environmental impact categories under investigation were Global Warming, Acidification and Terrestrial Eutrophication. The production of seaweed was identified to be the most energy intensive step. Scenario 1 showed better performance compared to scenario 2 for all impact categories, partly because of the energy intensive bioethanol separation process and the consequently lower overall efficiency of the system. For improved environmental performance, focus should be on optimization of seaweed production, bioethanol distillation, and management of digestate on land.

  16. 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

  17. 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.

  18. Lipid metabolism and potentials of biofuel and high added-value oil production in red algae.

    PubMed

    Sato, Naoki; Moriyama, Takashi; Mori, Natsumi; Toyoshima, Masakazu

    2017-04-01

    Biomass production is currently explored in microalgae, macroalgae and land plants. Microalgal biofuel development has been performed mostly in green algae. In the Japanese tradition, macrophytic red algae such as Pyropia yezoensis and Gelidium crinale have been utilized as food and industrial materials. Researches on the utilization of unicellular red microalgae such as Cyanidioschyzon merolae and Porphyridium purpureum started only quite recently. Red algae have relatively large plastid genomes harboring more than 200 protein-coding genes that support the biosynthetic capacity of the plastid. Engineering the plastid genome is a unique potential of red microalgae. In addition, large-scale growth facilities of P. purpureum have been developed for industrial production of biofuels. C. merolae has been studied as a model alga for cell and molecular biological analyses with its completely determined genomes and transformation techniques. Its acidic and warm habitat makes it easy to grow this alga axenically in large scales. Its potential as a biofuel producer is recently documented under nitrogen-limited conditions. Metabolic pathways of the accumulation of starch and triacylglycerol and the enzymes involved therein are being elucidated. Engineering these regulatory mechanisms will open a possibility of exploiting the full capability of production of biofuel and high added-value oil. In the present review, we will describe the characteristics and potential of these algae as biotechnological seeds.

  19. 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.

  20. 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

  1. 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.

  2. 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).

  3. 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.

  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.

  5. Engineering biofuel tolerance in non-native producing microorganisms.

    PubMed

    Jin, Hu; Chen, Lei; Wang, Jiangxin; Zhang, Weiwen

    2014-01-01

    Large-scale production of renewable biofuels through microbiological processes has drawn significant attention in recent years, mostly due to the increasing concerns on the petroleum fuel shortages and the environmental consequences of the over-utilization of petroleum-based fuels. In addition to native biofuel-producing microbes that have been employed for biofuel production for decades, recent advances in metabolic engineering and synthetic biology have made it possible to produce biofuels in several non-native biofuel-producing microorganisms. Compared to native producers, these non-native systems carry the advantages of fast growth, simple nutrient requirements, readiness for genetic modifications, and even the capability to assimilate CO2 and solar energy, making them competitive alternative systems to further decrease the biofuel production cost. However, the tolerance of these non-native microorganisms to toxic biofuels is naturally low, which has restricted the potentials of their application for high-efficiency biofuel production. To address the issues, researches have been recently conducted to explore the biofuel tolerance mechanisms and to construct robust high-tolerance strains for non-native biofuel-producing microorganisms. In this review, we critically summarize the recent progress in this area, focusing on three popular non-native biofuel-producing systems, i.e. Escherichia coli, Lactobacillus and photosynthetic cyanobacteria.

  6. 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.

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

    PubMed

    Cremonez, Paulo André; Feroldi, Michael; de Jesus de Oliveira, Carlos; Teleken, Joel Gustavo; Alves, Helton José; Sampaio, Silvio Cézar

    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.

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

    PubMed Central

    Colin, Verónica Leticia; Rodríguez, Analía; Cristóbal, Héctor 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

  9. 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.

  10. 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.

  11. Zymomonas mobilis as a model system for production of biofuels and biochemicals.

    PubMed

    Yang, Shihui; Fei, Qiang; Zhang, Yaoping; Contreras, Lydia M; Utturkar, Sagar M; Brown, Steven D; Himmel, Michael E; Zhang, Min

    2016-11-01

    Zymomonas mobilis is a natural ethanologen with many desirable industrial biocatalyst characteristics. In this review, we will discuss work to develop Z. mobilis as a model system for biofuel production from the perspectives of substrate utilization, development for industrial robustness, potential product spectrum, strain evaluation and fermentation strategies. This review also encompasses perspectives related to classical genetic tools and emerging technologies in this context. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  12. Zymomonas mobilis as a model system for production of biofuels and biochemicals

    DOE PAGES

    Yang, Shihui; Fei, Qiang; Zhang, Yaoping; ...

    2016-09-15

    Zymomonas mobilis is a natural ethanologen with many desirable industrial biocatalyst characteristics. In this review, we will discuss work to develop Z. mobilis as a model system for biofuel production from the perspectives of substrate utilization, development for industrial robustness, potential product spectrum, strain evaluation and fermentation strategies. Lastly, this review also encompasses perspectives related to classical genetic tools and emerging technologies in this context.

  13. Interactive association between biopolymers and biofunctions in carinata seeds as energy feedstock and their coproducts (carinata meal) from biofuel and bio-oil processing before and after biodegradation: current advanced molecular spectroscopic investigations.

    PubMed

    Yu, Peiqiang; Xin, Hangshu; Ban, Yajing; Zhang, Xuewei

    2014-05-07

    Recent advances in biofuel and bio-oil processing technology require huge supplies of energy feedstocks for processing. Very recently, new carinata seeds have been developed as energy feedstocks for biofuel and bio-oil production. The processing results in a large amount of coproducts, which are carinata meal. To date, there is no systematic study on interactive association between biopolymers and biofunctions in carinata seed as energy feedstocks for biofuel and bioethanol processing and their processing coproducts (carinata meal). Molecular spectroscopy with synchrotron and globar sources is a rapid and noninvasive analytical technique and is able to investigate molecular structure conformation in relation to biopolymer functions and bioavailability. However, to date, these techniques are seldom used in biofuel and bioethanol processing in other research laboratories. This paper aims to provide research progress and updates with molecular spectroscopy on the energy feedstock (carinata seed) and coproducts (carinata meal) from biofuel and bioethanol processing and show how to use these molecular techniques to study the interactive association between biopolymers and biofunctions in the energy feedstocks and their coproducts (carinata meal) from biofuel and bio-oil processing before and after biodegradation.

  14. Favouring butyrate production for a new generation biofuel by acidogenic glucose fermentation using cells immobilised on γ-alumina.

    PubMed

    Syngiridis, Kostas; Bekatorou, Argyro; Kandylis, Panagiotis; Larroche, Christian; Kanellaki, Maria; Koutinas, Athanasios A

    2014-06-01

    The effect of γ-alumina as a fermentation advancing tool and as carrier for culture immobilisation, regarding VFAs and ethanol production during acidogenic fermentation of glucose, was examined at various process conditions (sugar concentration, pH) and operation modes (continuous with and without effluent recirculation and batch). The results showed that at high initial pH (8.9) the continuous acidogenic fermentation of glucose led to high yields of VFAs and favoured the accumulation of butyric acid. The batch process on the other hand at pH 6.5, favoured the ethanol-type fermentation. The results indicate that in the frame of technology development for new generation biofuels, using γ-alumina as a process advancing tool at optimum process conditions (pH, initial glucose concentration and mode of operation), the produced VFAs profile and ethanol concentration may be manipulated. Copyright © 2014. Published by Elsevier Ltd.

  15. 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.

  16. 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.

  17. Hybrid-renewable processes for biofuels production: concentrated solar pyrolysis of biomass residues

    SciTech Connect

    George, Anthe; Geier, Manfred; Dedrick, Daniel E.

    2014-10-01

    The viability of thermochemically-derived biofuels can be greatly enhanced by reducing the process parasitic energy loads. Integrating renewable power into biofuels production is one method by which these efficiency drains can be eliminated. There are a variety of such potentially viable "hybrid-renewable" approaches; one is to integrate concentrated solar power (CSP) to power biomass-to-liquid fuels (BTL) processes. Barriers to CSP integration into BTL processes are predominantly the lack of fundamental kinetic and mass transport data to enable appropriate systems analysis and reactor design. A novel design for the reactor has been created that can allow biomass particles to be suspended in a flow gas, and be irradiated with a simulated solar flux. Pyrolysis conditions were investigated and a comparison between solar and non-solar biomass pyrolysis was conducted in terms of product distributions and pyrolysis oil quality. A novel method was developed to analyse pyrolysis products, and investigate their stability.

  18. 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.

  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.

  20. Engineering of microorganisms for the production of biofuels and perspectives based on systems metabolic engineering approaches.

    PubMed

    Jang, Yu-Sin; Park, Jong Myoung; Choi, Sol; Choi, Yong Jun; Seung, Do Young; Cho, Jung Hee; Lee, Sang Yup

    2012-01-01

    The increasing oil price and environmental concerns caused by the use of fossil fuel have renewed our interest in utilizing biomass as a sustainable resource for the production of biofuel. It is however essential to develop high performance microbes that are capable of producing biofuels with very high efficiency in order to compete with the fossil fuel. Recently, the strategies for developing microbial strains by systems metabolic engineering, which can be considered as metabolic engineering integrated with systems biology and synthetic biology, have been developed. Systems metabolic engineering allows successful development of microbes that are capable of producing several different biofuels including bioethanol, biobutanol, alkane, and biodiesel, and even hydrogen. In this review, the approaches employed to develop efficient biofuel producers by metabolic engineering and systems metabolic engineering approaches are reviewed with relevant example cases. It is expected that systems metabolic engineering will be employed as an essential strategy for the development of microbial strains for industrial applications. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Advanced glycation end products

    PubMed Central

    Gkogkolou, Paraskevi; Böhm, Markus

    2012-01-01

    Aging is the progressive accumulation of damage to an organism over time leading to disease and death. Aging research has been very intensive in the last years aiming at characterizing the pathophysiology of aging and finding possibilities to fight age-related diseases. Various theories of aging have been proposed. In the last years advanced glycation end products (AGEs) have received particular attention in this context. AGEs are formed in high amounts in diabetes but also in the physiological organism during aging. They have been etiologically implicated in numerous diabetes- and age-related diseases. Strategies inhibiting AGE accumulation and signaling seem to possess a therapeutic potential in these pathologies. However, still little is known on the precise role of AGEs during skin aging. In this review the existing literature on AGEs and skin aging will be reviewed. In addition, existing and potential anti-AGE strategies that may be beneficial on skin aging will be discussed. PMID:23467327

  2. Wastewater treatment high rate algal ponds (WWT HRAP) for low-cost biofuel production.

    PubMed

    Mehrabadi, Abbas; Craggs, Rupert; Farid, Mohammed M

    2015-05-01

    Growing energy demand and water consumption have increased concerns about energy security and efficient wastewater treatment and reuse. Wastewater treatment high rate algal ponds (WWT HRAPs) are a promising technology that could help solve these challenges concurrently where climate is favorable. WWT HRAPs have great potential for biofuel production as a by-product of WWT, since the costs of algal cultivation and harvest for biofuel production are covered by the wastewater treatment function. Generally, 800-1400 GJ/ha/year energy (average biomass energy content: 20 GJ/ton; HRAP biomass productivity: 40-70 tons/ha/year) can be produced in the form of harvestable biomass from WWT HRAP which can be used to provide community-level energy supply. In this paper the benefits of WWT HRAPs are compared with conventional mass algal culture systems. Moreover, parameters to effectively increase algal energy content and overall energy production from WWT HRAP are discussed including selection of appropriate algal biomass biofuel conversion pathways.

  3. 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.

  4. Production and harvesting of microalgae for wastewater treatment, biofuels, and bioproducts.

    PubMed

    Christenson, Logan; Sims, Ronald

    2011-01-01

    The integration of microalgae-based biofuel and bioproducts production with wastewater treatment has major advantages for both industries. However, major challenges to the implementation of an integrated system include the large-scale production of algae and the harvesting of microalgae in a way that allows for downstream processing to produce biofuels and other bioproducts of value. Although the majority of algal production systems use suspended cultures in either open ponds or closed reactors, the use of attached cultures may offer several advantages. With regard to harvesting methods, better understanding and control of autoflocculation and bioflocculation could improve performance and reduce chemical addition requirements for conventional mechanical methods that include centrifugation, tangential filtration, gravity sedimentation, and dissolved air flotation. There are many approaches currently used by companies and industries using clean water at laboratory, bench, and pilot scale; however, large-scale systems for controlled algae production and/or harvesting for wastewater treatment and subsequent processing for bioproducts are lacking. Further investigation and development of large-scale production and harvesting methods for biofuels and bioproducts are necessary, particularly with less studied but promising approaches such as those involving attached algal biofilm cultures.

  5. Engineering microbes for tolerance to next-generation biofuels

    PubMed Central

    2011-01-01

    A major challenge when using microorganisms to produce bulk chemicals such as biofuels is that the production targets are often toxic to cells. Many biofuels are known to reduce cell viability through damage to the cell membrane and interference with essential physiological processes. Therefore, cells must trade off biofuel production and survival, reducing potential yields. Recently, there have been several efforts towards engineering strains for biofuel tolerance. Promising methods include engineering biofuel export systems, heat shock proteins, membrane modifications, more general stress responses, and approaches that integrate multiple tolerance strategies. In addition, in situ recovery methods and media supplements can help to ease the burden of end-product toxicity and may be used in combination with genetic approaches. Recent advances in systems and synthetic biology provide a framework for tolerance engineering. This review highlights recent targeted approaches towards improving microbial tolerance to next-generation biofuels with a particular emphasis on strategies that will improve production. PMID:21936941

  6. 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.

  7. 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.

  8. 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

    2013-02-06

    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.

  9. 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.

  10. 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

  11. Lipid recovery from wet oleaginous microbial biomass for biofuel production: A critical review

    DOE PAGES

    Dong, Tao; Knoshaug, Eric P.; Pienkos, Philip T.; ...

    2016-06-15

    Biological lipids derived from oleaginous microorganisms are promising precursors for renewable biofuel productions. Direct lipid extraction from wet cell-biomass is favored because it eliminates the need for costly dehydration. However, the development of a practical and scalable process for extracting lipids from wet cell-biomass is far from ready to be commercialized, instead, requiring intensive research and development to understand the lipid accessibility, mechanisms in mass transfer and establish robust lipid extraction approaches that are practical for industrial applications. Furthermore, this paper aims to present a critical review on lipid recovery in the context of biofuel productions with special attention tomore » cell disruption and lipid mass transfer to support extraction from wet biomass.« less

  12. 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

  13. 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.

  14. Toward cell-free biofuel production: Stable immobilization of oligomeric enzymes.

    PubMed

    Grimaldi, J; Collins, C H; Belfort, G

    2014-01-01

    To overcome the main challenges facing alcohol-based biofuel production, we propose an alternate simplified biofuel production scheme based on a cell-free immobilized enzyme system. In this paper, we measured the activity of two tetrameric enzymes, a control enzyme with a colorimetric assay, β-galactosidase, and an alcohol-producing enzyme, alcohol dehydrogenase, immobilized on multiple surface curvatures and chemistries. Several solid supports including silica nanoparticles (convex), mesopourous silica (concave), diatomaceous earth (concave), and methacrylate (concave) were examined. High conversion rates and low protein leaching was achieved by covalent immobilization of both enzymes on methacrylate resin. Alcohol dehydrogenase (ADH) exhibited long-term stability and over 80% conversion of aldehyde to alcohol over 16 days of batch cycles. The complete reaction scheme for the conversion of acid to aldehyde to alcohol was demonstrated in vitro by immobilizing ADH with keto-acid decarboxylase free in solution. © 2014 American Institute of Chemical Engineers.

  15. Enhanced biofuel production through coupled acetic acid and xylose consumption by engineered yeast.

    PubMed

    Wei, Na; Quarterman, Josh; Kim, Soo Rin; Cate, Jamie H D; Jin, Yong-Su

    2013-01-01

    The anticipation for substituting conventional fossil fuels with cellulosic biofuels is growing in the face of increasing demand for energy and rising concerns of greenhouse gas emissions. However, commercial production of cellulosic biofuel has been hampered by inefficient fermentation of xylose and the toxicity of acetic acid, which constitute substantial portions of cellulosic biomass. Here we use a redox balancing strategy to enable efficient xylose fermentation and simultaneous in situ detoxification of cellulosic feedstocks. By combining a nicotinamide adenine dinucleotide (NADH)-consuming acetate consumption pathway and an NADH-producing xylose utilization pathway, engineered yeast converts cellulosic sugars and toxic levels of acetate together into ethanol under anaerobic conditions. The results demonstrate a breakthrough in making efficient use of carbon compounds in cellulosic biomass and present an innovative strategy for metabolic engineering whereby an undesirable redox state can be exploited to drive desirable metabolic reactions, even improving productivity and yield.

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

    PubMed

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

    2008-06-01

    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.

  17. 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.

  18. Energy Security Requires Diversity: An Argument for The Defense Production Act Title III Biofuel Initiative

    DTIC Science & Technology

    2013-06-19

    the United States . 125 The President is further authorized to ensure that critical components, critical technology items, essential materials , and...plant mass that is not part of human diet and is not cultivated or is a byproduct of cultivated (for example forest woody biomass , corn stover...security. The United States Navy has taken the lead in this charge by proposing the Defense Production Act (DPA) Title III Biofuel Initiative to

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. Effects on carbon and nitrogen emissions due to swine manure removal for biofuel production.

    PubMed

    Weaver, Kim H; Harper, Lowry A; Brown, Sarah M

    2012-01-01

    Methane (CH) and ammonia (NH) are emitted from swine-manure processing lagoons, contributing to global climate change and reducing air quality. Manure diverted to biofuel production is proposed as a means to reduce CH emissions. At a swine confined animal feeding operation in the U.S. Central Great Basin, animal manure was diverted from 12 farms to a biofuel facility and converted to methanol. Ammonia emissions were determined using the De Visscher Model from measured data of dissolved lagoon ammoniacal N concentrations, pH, temperature, and wind speed at the lagoon sites. Other lagoon gas emissions were measured with subsurface gas collection devices and gas chromatography analysis. During 2 yr of study, CO and CH emissions from the primary lagoons decreased 11 and 12%, respectfully, as a result of the biofuel process, compared with concurrently measured control lagoon emissions. Ammonia emissions increased 47% compared with control lagoons. The reduction of CH and increase in NH emissions agrees with a short-term study measured at this location by Lagrangian inverse dispersion analysis. The increase in NH emissions was primarily due to an increase in lagoon solution pH attributable to decreased methanogenesis. Also observed due to biofuel production was a 20% decrease in conversion of total ammoniacal N to N, a secondary process for the removal of N in anaerobic waste lagoons. The increase in NH emissions can be partially attributed to the decrease in N production by a proposed NH conversion to N mechanism. This mechanism predicts that a decrease in NH conversion to N increases ammoniacal N pH. Both effects increase NH emissions. It is unknown whether the decrease in NH conversion to N is a direct or physical result of the decrease in methanogenesis. Procedures and practices intended to reduce emissions of one pollutant can have an unintended consequence on the emissions of another pollutant. Copyright © by the American Society of Agronomy, Crop Science Society

  4. Hybridization and adaptive evolution of diverse Saccharomyces species for cellulosic biofuel production.

    PubMed

    Peris, David; Moriarty, Ryan V; Alexander, William G; Baker, EmilyClare; Sylvester, Kayla; Sardi, Maria; Langdon, Quinn K; Libkind, Diego; Wang, Qi-Ming; Bai, Feng-Yan; Leducq, Jean-Baptiste; Charron, Guillaume; Landry, Christian R; Sampaio, José Paulo; Gonçalves, Paula; Hyma, Katie E; Fay, Justin C; Sato, Trey K; Hittinger, Chris Todd

    2017-01-01

    Lignocellulosic biomass is a common resource across the globe, and its fermentation offers a promising option for generating renewable liquid transportation fuels. The deconstruction of lignocellulosic biomass releases sugars that can be fermented by microbes, but these processes also produce fermentation inhibitors, such as aromatic acids and aldehydes. Several research projects have investigated lignocellulosic biomass fermentation by the baker's yeast Saccharomyces cerevisiae. Most projects have taken synthetic biological approaches or have explored naturally occurring diversity in S. cerevisiae to enhance stress tolerance, xylose consumption, or ethanol production. Despite these efforts, improved strains with new properties are needed. In other industrial processes, such as wine and beer fermentation, interspecies hybrids have combined important traits from multiple species, suggesting that interspecies hybridization may also offer potential for biofuel research. To investigate the efficacy of this approach for traits relevant to lignocellulosic biofuel production, we generated synthetic hybrids by crossing engineered xylose-fermenting strains of S. cerevisiae with wild strains from various Saccharomyces species. These interspecies hybrids retained important parental traits, such as xylose consumption and stress tolerance, while displaying intermediate kinetic parameters and, in some cases, heterosis (hybrid vigor). Next, we exposed them to adaptive evolution in ammonia fiber expansion-pretreated corn stover hydrolysate and recovered strains with improved fermentative traits. Genome sequencing showed that the genomes of these evolved synthetic hybrids underwent rearrangements, duplications, and deletions. To determine whether the genus Saccharomyces contains additional untapped potential, we screened a genetically diverse collection of more than 500 wild, non-engineered Saccharomyces isolates and uncovered a wide range of capabilities for traits relevant to

  5. 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

  6. 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.

  7. 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.

  8. Production of biofuel using molluscan pseudofeces derived from algal cells

    DOEpatents

    Das, Keshav C.; Chinnasamy, Senthil; Shelton, James; Wilde, Susan B.; Haynie, Rebecca S.; Herrin, James A.

    2012-08-28

    Embodiments of the present disclosure provide for novel strategies to harvest algal lipids using mollusks which after feeding algae from the growth medium can convert algal lipids into their biomass or excrete lipids in their pseudofeces which makes algae harvesting energy efficient and cost effective. The bioconverter, filter-feeding mollusks and their pseudofeces can be harvested and converted to biocrude using an advanced thermochemical liquefaction technology. Methods, systems, and materials are disclosed for the harvest and isolation of algal lipids from the mollusks, molluscan feces and molluscan pseudofeces.

  9. 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.

  10. Production of biofuels from pretreated microalgae biomass by anaerobic fermentation with immobilized Clostridium acetobutylicum cells.

    PubMed

    Efremenko, E N; Nikolskaya, A B; Lyagin, I V; Senko, O V; Makhlis, T A; Stepanov, N A; Maslova, O V; Mamedova, F; Varfolomeev, S D

    2012-06-01

    The purpose of this work was to study the possible use of pretreated biomass of various microalgae and cyanobacteria as substrates for acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobutylicum cells immobilized into poly(vinyl alcohol) cryogel. To this end, the biochemical composition of photosynthetic microorganisms cultivated under various conditions was studied. The most efficient technique for pretreating microalgal biomass for its subsequent conversion into biofuels appeared to be thermal decomposition at 108 °C. For the first time the maximum productivity of the ABE fermentation in terms of hydrogen (8.5 mmol/L medium/day) was obtained using pretreated biomass of Nannochloropsis sp. Maximum yields of butanol and ethanol were observed with Arthrospira platensis biomass used as the substrate. Immobilized Clostridium cells were demonstrated to be suitable for multiple reuses (for a minimum of five cycles) in ABE fermentation for producing biofuels from pretreated microalgal biomass. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Assessing microalgae biorefinery routes for the production of biofuels via hydrothermal liquefaction.

    PubMed

    López Barreiro, Diego; Samorì, Chiara; Terranella, Giuseppe; Hornung, Ursel; Kruse, Andrea; Prins, Wolter

    2014-12-01

    The interest in third generation biofuels from microalgae has been rising during the past years. Meanwhile, it seems not economically feasible to grow algae just for biofuels. Co-products with a higher value should be produced by extracting a particular algae fraction to improve the economics of an algae biorefinery. The present study aims at analyzing the influence of two main microalgae components (lipids and proteins) on the composition and quantity of biocrude oil obtained via hydrothermal liquefaction of two strains (Nannochloropsis gaditana and Scenedesmus almeriensis). The algae were liquefied as raw biomass, after extracting lipids and after extracting proteins in microautoclave experiments at different temperatures (300-375°C) for 5 and 15min. The results indicate that extracting the proteins from the microalgae prior to HTL may be interesting to improve the economics of the process while at the same time reducing the nitrogen content of the biocrude oil.

  12. Broadband Microwave Study of Reaction Intermediates and Products Through the Pyrolysis of Oxygenated Biofuels

    NASA Astrophysics Data System (ADS)

    Abeysekera, Chamara; Hernandez-Castillo, Alicia O.; Fritz, Sean; Zwier, Timothy S.

    2017-06-01

    The rapidly growing list of potential plant-derived biofuels creates a challenge for the scientific community to provide a molecular-scale understanding of their combustion. Development of accurate combustion models rests on a foundation of experimental data on the kinetics and product branching ratios of their individual reaction steps. Therefore, new spectroscopic tools are necessary to selectively detect and characterize fuel components and reactive intermediates generated by pyrolysis and combustion. Substituted furans, including furanic ethers, are considered second-generation biofuel candidates. Following the work of the Ellison group, an 8-18 GHz microwave study was carried out on the unimolecular and bimolecular decomposition of the smallest furanic ether, 2-methoxy furan, and it`s pyrolysis intermediate, the 2-furanyloxy radical, formed in a high-temperature pyrolysis source coupled to a supersonic expansion. Details of the experimental setup and analysis of the spectrum of the radical will be discussed.

  13. Inhibition of microbial biofuel production in drought-stressed switchgrass hydrolysate

    DOE PAGES

    Ong, Rebecca Garlock; Higbee, Alan; Bottoms, Scott; ...

    2016-11-08

    Here, interannual variability in precipitation, particularly drought, can affect lignocellulosic crop biomass yields and composition, and is expected to increase biofuel yield variability. However, the effect of precipitation on downstream fermentation processes has never been directly characterized. In order to investigate the impact of interannual climate variability on biofuel production, corn stover and switchgrass were collected during 3 years with significantly different precipitation profiles, representing a major drought year (2012) and 2 years with average precipitation for the entire season (2010 and 2013). All feedstocks were AFEX (ammonia fiber expansion)-pretreated, enzymatically hydrolyzed, and the hydrolysates separately fermented using xylose-utilizing strainsmore » of Saccharomyces cerevisiae and Zymomonas mobilis. As a result, a chemical genomics approach was also used to evaluate the growth of yeast mutants in the hydrolysates.« less

  14. Inhibition of microbial biofuel production in drought-stressed switchgrass hydrolysate

    SciTech Connect

    Ong, Rebecca Garlock; Higbee, Alan; Bottoms, Scott; Dickinson, Quinn; Xie, Dan; Smith, Scott A.; Serate, Jose; Pohlmann, Edward; Jones, Arthur Daniel; Coon, Joshua J.; Sato, Trey K.; Sanford, Gregg R.; Eilert, Dustin; Oates, Lawrence G.; Piotrowski, Jeff S.; Bates, Donna M.; Cavalier, David; Zhang, Yaoping

    2016-11-08

    Here, interannual variability in precipitation, particularly drought, can affect lignocellulosic crop biomass yields and composition, and is expected to increase biofuel yield variability. However, the effect of precipitation on downstream fermentation processes has never been directly characterized. In order to investigate the impact of interannual climate variability on biofuel production, corn stover and switchgrass were collected during 3 years with significantly different precipitation profiles, representing a major drought year (2012) and 2 years with average precipitation for the entire season (2010 and 2013). All feedstocks were AFEX (ammonia fiber expansion)-pretreated, enzymatically hydrolyzed, and the hydrolysates separately fermented using xylose-utilizing strains of Saccharomyces cerevisiae and Zymomonas mobilis. As a result, a chemical genomics approach was also used to evaluate the growth of yeast mutants in the hydrolysates.

  15. 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

    2016-04-15

    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.

  16. Bioprospecting for hyper-lipid producing microalgal strains for sustainable biofuel production.

    PubMed

    Mutanda, T; Ramesh, D; Karthikeyan, S; Kumari, S; Anandraj, A; Bux, F

    2011-01-01

    Global petroleum reserves are shrinking at a fast pace, increasing the demand for alternate fuels. Microalgae have the ability to grow rapidly, and synthesize and accumulate large amounts (approximately 20-50% of dry weight) of neutral lipid stored in cytosolic lipid bodies. A successful and economically viable algae based biofuel industry mainly depends on the selection of appropriate algal strains. The main focus of bioprospecting for microalgae is to identify unique high lipid producing microalgae from different habitats. Indigenous species of microalgae with high lipid yields are especially valuable in the biofuel industry. Isolation, purification and identification of natural microalgal assemblages using conventional techniques is generally time consuming. However, the recent use of micromanipulation as a rapid isolating tool allows for a higher screening throughput. The appropriate media and growth conditions are also important for successful microalgal proliferation. Environmental parameters recorded at the sampling site are necessary to optimize in vitro growth. Identification of species generally requires a combination of morphological and genetic characterization. The selected microalgal strains are grown in upscale systems such as raceway ponds or photobireactors for biomass and lipid production. This paper reviews the recent methodologies adopted for site selection, sampling, strain selection and identification, optimization of cultural conditions for superior lipid yield for biofuel production. Energy generation routes of microalgal lipids and biomass are discussed in detail.

  17. Lactobacillus casei as a biocatalyst for biofuel production.

    PubMed

    Vinay-Lara, Elena; Wang, Song; Bai, Lina; Phrommao, Ekkarat; Broadbent, Jeff R; Steele, James L

    2016-09-01

    Microbial fermentation of sugars from plant biomass to alcohols represents an alternative to petroleum-based fuels. The optimal biocatalyst for such fermentations needs to overcome hurdles such as high concentrations of alcohols and toxic compounds. Lactic acid bacteria, especially lactobacilli, have high innate alcohol tolerance and are remarkably adaptive to harsh environments. This study assessed the potential of five Lactobacillus casei strains as biocatalysts for alcohol production. L. casei 12A was selected based upon its innate alcohol tolerance, high transformation efficiency and ability to utilize plant-derived carbohydrates. A 12A derivative engineered to produce ethanol (L. casei E1) was compared to two other bacterial biocatalysts. Maximal growth rate, maximal optical density and ethanol production were determined under conditions similar to those present during alcohol production from lignocellulosic feedstocks. L. casei E1 exhibited higher innate alcohol tolerance, better growth in the presence of corn stover hydrolysate stressors, and resulted in higher ethanol yields.

  18. Biofuel production from Jerusalem artichoke tuber inulins: a review

    DOE PAGES

    Bhagia, Samarthya; Akinosho, Hannah; Ferreira, Jorge F. S.; ...

    2017-06-01

    Jerusalem artichoke (JA) has a high productivity of tubers that are rich in inulins, a fructan polymer. These inulins can be easily broken down into fructose and glucose for conversion into ethanol by fermentation. This paper discusses tuber and inulin yields, effect of cultivar and environment on tuber productivity, and approaches to fermentation for ethanol production. Consolidated bioprocessing with Kluyveromyces marxianus has been the most popular approach for fermentation into ethanol. Apart from ethanol, fructose can be dehydrated into into 5-hydrolxymethylfurfural followed by catalytic conversion into hydrocarbons. Finally, findings from several studies indicate that this plant from tubers alone canmore » produce ethanol at yields that rival corn and sugarcane ethanol. JA has tremendous potential for use as a bioenergy feedstock.« less

  19. 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.

  20. Engineering modular polyketide synthases for production of biofuels and industrial chemicals.

    PubMed

    Cai, Wenlong; Zhang, Wenjun

    2017-09-22

    Polyketide synthases (PKSs) are one of the most profound biosynthetic factories for producing polyketides with diverse structures and biological activities. These enzymes have been historically studied and engineered to make un-natural polyketides for drug discovery, and have also recently been explored for synthesizing biofuels and industrial chemicals due to their versatility and customizability. Here, we review recent advances in the mechanistic understanding and engineering of modular PKSs for producing polyketide-derived chemicals, and provide perspectives on this relatively new application of PKSs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Outdoor Cultivation of Marine Diatoms for Year-Round Production of Biofuels.

    PubMed

    Matsumoto, Mitsufumi; Nojima, Daisuke; Nonoyama, Tomomi; Ikeda, Kiichi; Maeda, Yoshiaki; Yoshino, Tomoko; Tanaka, Tsuyoshi

    2017-03-25

    Biofuel production using microalgae is believed to have the advantage of continuous year-round production over crop plants, which have strong seasonality. However, actual year-round production of microalgal lipids using outdoor mass cultivation has rarely been demonstrated. In our previous study, it was demonstrated that the oleaginous diatom, Fistulifera solaris, was culturable in outdoor bioreactors from spring to autumn, whereas biomass and lipid production in winter failed because F. solaris did not grow below 15 °C. Therefore, another candidate strain that is culturable in winter is required. In this study, a cold-tolerant diatom, Mayamaea sp. JPCC CTDA0820, was selected as a promising candidate for biofuel production in winter. Laboratory-scale characterization revealed that this diatom was culturable at temperatures as low as 10 °C. Subsequently, F. solaris (April-October) and Mayamaea sp. JPCC CTDA0820 (November-March) were cultured in outdoor open-pond bioreactors, wherein year-round production of diatom lipids was successfully demonstrated. The maximal values of areal productivities of biomass and lipids reached to 9.79 and 1.80 g/(m² day) for F. solaris, and 8.62 and 0.92 g/(m² day) for Mayamaea sp. JPCC CTDA0820, respectively. With the combined use of these two diatom species, stable year-round production of microalgal lipids became possible.

  2. Outdoor Cultivation of Marine Diatoms for Year-Round Production of Biofuels

    PubMed Central

    Matsumoto, Mitsufumi; Nojima, Daisuke; Nonoyama, Tomomi; Ikeda, Kiichi; Maeda, Yoshiaki; Yoshino, Tomoko; Tanaka, Tsuyoshi

    2017-01-01

    Biofuel production using microalgae is believed to have the advantage of continuous year-round production over crop plants, which have strong seasonality. However, actual year-round production of microalgal lipids using outdoor mass cultivation has rarely been demonstrated. In our previous study, it was demonstrated that the oleaginous diatom, Fistulifera solaris, was culturable in outdoor bioreactors from spring to autumn, whereas biomass and lipid production in winter failed because F. solaris did not grow below 15 °C. Therefore, another candidate strain that is culturable in winter is required. In this study, a cold-tolerant diatom, Mayamaea sp. JPCC CTDA0820, was selected as a promising candidate for biofuel production in winter. Laboratory-scale characterization revealed that this diatom was culturable at temperatures as low as 10 °C. Subsequently, F. solaris (April–October) and Mayamaea sp. JPCC CTDA0820 (November–March) were cultured in outdoor open-pond bioreactors, wherein year-round production of diatom lipids was successfully demonstrated. The maximal values of areal productivities of biomass and lipids reached to 9.79 and 1.80 g/(m2 day) for F. solaris, and 8.62 and 0.92 g/(m2 day) for Mayamaea sp. JPCC CTDA0820, respectively. With the combined use of these two diatom species, stable year-round production of microalgal lipids became possible. PMID:28346334

  3. Processing of Brassica seeds for feedstock in biofuels production

    USDA-ARS?s Scientific Manuscript database

    Several Brassica species are currently being evaluated to develop regionalized production systems based on their suitability to the environment and with the prevailing practices of growing commodity food crops like wheat, corn, and soybeans. This integrated approach to farming will provide high qual...

  4. 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.

  5. 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.

  6. Production of biofuels and biochemicals: in need of an ORACLE.

    PubMed

    Miskovic, Ljubisa; Hatzimanikatis, Vassily

    2010-08-01

    The engineering of cells for the production of fuels and chemicals involves simultaneous optimization of multiple objectives, such as specific productivity, extended substrate range and improved tolerance - all under a great degree of uncertainty. The achievement of these objectives under physiological and process constraints will be impossible without the use of mathematical modeling. However, the limited information and the uncertainty in the available information require new methods for modeling and simulation that will characterize the uncertainty and will quantify, in a statistical sense, the expectations of success of alternative metabolic engineering strategies. We discuss these considerations toward developing a framework for the Optimization and Risk Analysis of Complex Living Entities (ORACLE) - a computational method that integrates available information into a mathematical structure to calculate control coefficients. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Microalgae-based biorefinery--from biofuels to natural products.

    PubMed

    Yen, Hong-Wei; Hu, I-Chen; Chen, Chun-Yen; Ho, Shih-Hsin; Lee, Duu-Jong; Chang, Jo-Shu

    2013-05-01

    The potential for biodiesel production from microalgal lipids and for CO2 mitigation due to photoautotrophic growth of microalgae have recently been recognized. Microalgae biomass also has other valuable components, including carbohydrates, long chain fatty acids, pigments and proteins. The microalgae-based carbohydrates consist mainly of cellulose and starch without lignin; thus they can be ready carbon source for the fermentation industry. Some microalgae can produce long chain fatty acids (such as DHA and EPA) as valuable health food supplements. In addition, microalgal pigments and proteins have considerable potential for many medical applications. This review article presents comprehensive information on the current state of these commercial applications, as well as the utilization and characteristics of the microalgal components, in addition to the key factors and challenges that should be addressed during the production of these materials, and thus provides a useful report that can aid the development of an efficient microalgae-based biorefinery process.

  8. Evaluation of filamentous green algae as feedstocks for biofuel production.

    PubMed

    Zhang, Wei; Zhao, Yonggang; Cui, Binjie; Wang, Hui; Liu, Tianzhong

    2016-11-01

    Compared with unicellular microalgae, filamentous algae have high resistance to grazer-predation and low-cost recovery in large-scale production. Green algae, as the most diverse group of algae, included numerous filamentous genera and species. In this study, records of filamentous genera and species in green algae were firstly censused and classified. Then, seven filamentous strains subordinated in different genera were cultivated in bubbled-column to investigate their growth rate and energy molecular (lipid and starch) capacity. Four strains including Stigeoclonium sp., Oedogonium nodulosum, Hormidium sp. and Zygnema extenue were screened out due to their robust growth. And they all could accumulate triacylglycerols and starch in their biomass, but with different capacity. After nitrogen starvation, Hormidium sp. and Oedogonium nodulosum respectively exhibited high capacity of lipid (45.38% in dry weight) and starch (46.19% in dry weight) accumulation, which could be of high potential as feedstocks for biodiesel and bioethanol production.

  9. CO{sub 2} capture and biofuels production with microalgae

    SciTech Connect

    Benemann, J.R.

    1995-11-01

    Microalgae cultivation in large open ponds is the only biological process capable of directly utilizing power plant flue gas CO{sub 2} for production of renewable fuels, such as biodiesel, thus mitigating the potential for global warming. Past and recent systems studies have concluded that in principle this concept could be economically feasible, but that this technology still requires both fundamental and applied long-term R&D.

  10. 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.

  11. 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

  12. Characterization of sugarcane (Saccharum spp.) leaf senescence: implications for biofuel production.

    PubMed

    Martins, Maria Thereza Bazzo; de Souza, Wagner Rodrigo; da Cunha, Bárbara Andrade Dias Brito; Basso, Marcos Fernando; de Oliveira, Nelson Geraldo; Vinecky, Felipe; Martins, Polyana Kelly; de Oliveira, Patrícia Abrão; Arenque-Musa, Bruna Cersózimo; de Souza, Amanda Pereira; Buckeridge, Marcos Silveira; Kobayashi, Adilson Kenji; Quirino, Betania Ferraz; Molinari, Hugo Bruno Correa

    2016-01-01

    Second-generation ethanol (2G-bioethanol) uses lignocellulosic feedstocks for ethanol production. Sugarcane is one among the most suitable crops for biofuel production. Its juice is extracted for sugar production, while sugarcane bagasse, straw, and senescing leaves are considered industrial waste. Senescence is the age-dependent deterioration of plant cells, ultimately leading to cell death and completion of the plant life cycle. Because senescing leaves may also be used for biofuel production, understanding the process of natural senescence, including remobilization of nutrients and its effect on cell walls can provide useful information for 2G-bioethanol production from sugarcane leaves. The natural senescence process in leaves of the commercial sugarcane cultivar RB867515 was investigated. Senescence was characterized by strong reduction in photosynthetic pigments content, remobilization of the nutrients N, P, K, B, Cu, Fe, and Zn, and accumulation of Ca, S, Mg, B, Mn, and Al. No significant changes in the cell-wall composition occurred, and only small changes in the expression of cell wall-related genes were observed, suggesting that cell walls are preserved during senescence. Senescence-marker genes, such as SAG12-like and XET-like genes, were also identified in sugarcane and found to be highly expressed. Our study on nutrient remobilization under senescence in a vigorous sugarcane cultivar can contribute to the understanding on how nutrient balance in a high-yielding crop is achieved. In general, neutral monosaccharide profile did not change significantly with leaf senescence, suggesting that senescing leaves of sugarcane can be as a feedstock for biofuel production using pretreatments established for non-senescing leaves without additional efforts. Based on our findings, the potential biotechnological applications for the improvement of sugarcane cultivars are discussed.

  13. 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

  14. 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%).

  15. 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.

  16. Biofuel feedstocks

    USDA-ARS?s Scientific Manuscript database

    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...

  17. Synergistic temperature and ethanol effect on Saccharomyces cerevisiae dynamic behaviour in ethanol bio-fuel production.

    PubMed

    Aldiguier, A S; Alfenore, S; Cameleyre, X; Goma, G; Uribelarrea, J L; Guillouet, S E; Molina-Jouve, C

    2004-07-01

    The impact of ethanol and temperature on the dynamic behaviour of Saccharomyces cerevisiae in ethanol biofuel production was studied using an isothermal fed-batch process at five different temperatures. Fermentation parameters and kinetics were quantified. The best performances were found at 30 and 33 degrees C around 120 g l(-1) ethanol produced in 30 h with a slight benefit for growth at 30 degrees C and for ethanol production at 33 degrees C. Glycerol formation, enhanced with increasing temperatures, was coupled with growth for all fermentations; whereas, a decoupling phenomenon occurred at 36 and 39 degrees C pointing out a possible role of glycerol in yeast thermal protection.

  18. 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, α-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).

  19. 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.

  20. Exploration of Natural Biomass Utilization Systems (NBUS) for advanced biofuel--from systems biology to synthetic design.

    PubMed

    Xie, Shangxian; Syrenne, Ryan; Sun, Su; Yuan, Joshua S

    2014-06-01

    Efficient degradation and utilization of lignocellulosic biomass remains a challenge for sustainable and affordable biofuels. Various natural biomass utilization systems (NBUS) evolved the capacity to combat the recalcitrance of plant cell walls. The study of these NBUS could enable the development of efficient and cost-effective biocatalysts, microorganisms, and bioprocesses for biofuels and bioproducts. Here, we reviewed the recent research progresses for several NBUS, ranging from single cell microorganisms to consortiums such as cattle rumen and insect guts. These studies aided the discovery of biomass-degrading enzymes and the elucidation of the evolutionary and functional relevance in these systems. In particular, advances in the next generation 'omics' technologies offered new opportunities to explore NBUS in a high-throughput manner. Systems biology helped to facilitate the rapid biocatalyst discovery and detailed mechanism analysis, which could in turn guide the reverse design of engineered microorganisms and bioprocesses for cost-effective and efficient biomass conversion.

  1. 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.

  2. Primary productivity and the prospects for biofuels in the United Kingdom

    NASA Astrophysics Data System (ADS)

    Lawson, G. J.; Callaghan, T. V.

    1983-09-01

    Estimates of land use and plant productivity are combined to predict total annual primary production in the UK as 252 million tonnes dry matter (10.5 t ha-1yr-1). Annual above ground production is predicted to be 165 Mt (6.9 t ha-1yr-1). Within these totals, intensive agriculture contributes 60%, productive woodland 8%, natural vegetation 26% and urban vegetation 5%. However, only 25% of total plant production is cropped by man and animals, and most of this is subsequently discarded as wastes and residues. 2112 PJ of organic material is available for fuel without reducing food or fibre production, but since much of this could not be economically collected, 859 PJ is calculated as a more realistic biofuel contribution by the year 2000. After deducting 50% conversion losses, this could save P1 billion (1979 prices) in oil imports. Short rotation energy plantations, forest residues, coppice woodlands, animal and crop wastes, industrial and domestic wastes, catch crops, natural vegetation and urban vegetation all have immediate or short term potential as biofuel sources. Sensitive planning is required to reduce environmental impact, but in some cases more diverse wildlife habitats may be created.

  3. An integrated assessment of location-dependent scaling for microalgae biofuel production facilities

    DOE PAGES

    Coleman, André M.; Abodeely, Jared M.; Skaggs, Richard L.; ...

    2014-06-19

    Successful development of a large-scale microalgae-based biofuels industry requires comprehensive analysis and understanding of the feedstock supply chain—from facility siting and design through processing and 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 partially addressed 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 microalgae production facility.more » This is done by analyzing how variability and uncertainty over space and through time affect 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. To provide a baseline analysis, the IAF was applied in this paper to a set of sites in the southeastern U.S. with the potential to cumulatively produce 5 billion gallons per year. Finally, the results indicate costs can be reduced by scaling downstream processing capabilities to fit site-specific growing conditions, available and economically viable resources, and specific microalgal strains.« less

  4. An integrated assessment of location-dependent scaling for microalgae biofuel production facilities

    SciTech Connect

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

    2014-07-01

    Successful development of a large-scalemicroalgae-based biofuels industry requires comprehensive analysis and understanding of the feedstock supply chain—fromfacility siting and design through processing and 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 partially addressed 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 microalgae production facility. This is done by analyzing howvariability and uncertainty over space and through time affect 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. To provide a baseline analysis, the IAF was applied to a set of sites in the southeastern U.S. with the potential to cumulatively produce 5 billion gallons per year. The results indicate costs can be reduced by scaling downstream processing capabilities to fit site-specific growing conditions, available and economically viable resources, and specific microalgal strains.

  5. 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.

  6. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. 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

  8. Microalgae for high-value compounds and biofuels production: a review with focus on cultivation under stress conditions.

    PubMed

    Markou, Giorgos; Nerantzis, Elias

    2013-12-01

    Microalgal biomass as feedstock for biofuel production is an attracting alternative to terrestrial plant utilization for biofuels production. However, today the microalgal cultivation systems for energy production purposes seem not yet to be economically feasible. Microalgae, though cultivated under stress conditions, such as nutrient starvation, high salinity, high temperature etc. accumulate considerable amounts (up to 60-65% of dry weight) of lipids or carbohydrates along with several secondary metabolites. Especially some of the latter are valuable compounds with an enormous range of industrial applications. The simultaneous production of lipids or carbohydrates for biofuel production and of secondary metabolites in a biorefinery concept might allow the microalgal production to be economically feasible. This paper aims to provide a review on the available literature about the cultivation of microalgae for the accumulation of high-value compounds along with lipids or carbohydrates focusing on stress cultivation conditions.

  9. Recent Inventions and Trends in Algal Biofuels Research.

    PubMed

    Karemore, Ankush; Nayak, Manoranjan; Sen, Ramkrishna

    2016-01-01

    In recent times, when energy crisis compounded by global warming and climate change is receiving worldwide attention, the emergence of algae, as a better feedstock for third-generation biofuels than energy crops or plants, holds great promise. As compared to conventional biofuels feedstocks, algae offer several advantages and can alone produce a significant amount of biofuels sustainably in a shorter period to fulfill the rising demand for energy. Towards commercialisation, there have been numerous efforts put for- ward for the development of algae-derived biofuel. This article reviews and summarizes the recent inventions and the current trends that are reported and captured in relevant patents pertaining to the novel methods of algae biomass cultivation and processing for biofuels and value-added products. In addition, the recent advancement in techniques and technologies for microalgal biofuel production has been highlighted. Various steps involved in the production of algal biofuels have been considered in this article. Moreover, the work that advances to improve the efficiency and cost-effectiveness of the processes for the manufacture of biofuels has been presented. Our survey was conducted in the patent databases: WIPO, Spacenet and USPTO. There are still some technological bottlenecks that could be overcome by designing advanced photobioreactor and raceway ponds, developing new and low cost technologies for biomass cultivation, harvesting, drying and extraction. Recent advancement in algae biofuels methods is directed toward developing efficient and integrated systems to produce biofuels by overcoming the current challenges. However, further research effort is required to scale-up and improve the efficiency of these methods in the upstream and downstream technologies to make the cost of biofuels competitive with petroleum fuels.

  10. 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.

  11. Surface water retention systems for cattail production as a biofuel.

    PubMed

    Berry, Pamela; Yassin, Fuad; Grosshans, Richard; Lindenschmidt, Karl-Erich

    2017-12-01

    Surface water retention systems act to reduce nutrient pollution by collecting excess nutrients within a watershed via runoff. Harvesting aquatic biomass, such as the invasive cattail, from retention systems removes nutrients absorbed by the plant from the ecosystem permanently. Harvested biomass can be used as a renewable energy source in place of fossil fuels, offsetting carbon emissions. The purpose of this research was to simulate cattail harvest from surface water retention systems to determine their ability to provide suitable growing conditions with annual fluctuations in water availability. The economic and environmental benefits associated with nutrient removal and carbon offsets were also calculated and monetized. A proposed upstream and existing downstream water retention system in southern Manitoba were modelled using a system dynamics model with streamflow inputs provided by a physical hydrologic model, Modélisation Environmentale Communautaire - Surface and Hydrology (MESH). Harvesting cattail and other unconventional feedstocks, such as reeds, sedges, and grasses, from retention systems provided a viable revenue stream for landowners over a ten-year period. This practice generates income for landowners via biomass and carbon credit production on otherwise underutilized marginal cropland invaded with cattail. The economic benefits promote wetland habitat restoration while managing cattail growth to maintain biodiversity. Excess nitrogen and phosphorus are also removed from the ecosystem, reducing downstream nutrient loading. Utilizing surface water retention systems for cattail harvest is a best management strategy for nutrient retention on the landscape and improving agricultural resilience. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Production of biofuels, limonene and pectin from citrus wastes.

    PubMed

    Pourbafrani, Mohammad; Forgács, Gergely; Horváth, Ilona Sárvári; Niklasson, Claes; Taherzadeh, Mohammad J

    2010-06-01

    Production of ethanol, biogas, pectin and limonene from citrus wastes (CWs) by an integrated process was investigated. CWs were hydrolyzed by dilute-acid process in a pilot plant reactor equipped with an explosive drainage. Hydrolysis variables including temperature and residence time were optimized by applying a central composite rotatable experimental design (CCRD). The best sugar yield (0.41g/g of the total dry CWs) was obtained by dilute-acid hydrolysis at 150 degrees C and 6min residence time. At this condition, high solubilization of pectin present in the CWs was obtained, and 77.6% of total pectin content of CWs could be recovered by solvent recovery. Degree of esterification and ash content of produced pectin were 63.7% and 4.23%, respectively. In addition, the limonene of the CWs was effectively removed through flashing of the hydrolyzates into an expansion tank. The sugars present in the hydrolyzates were converted to ethanol using baker's yeast, while an ethanol yield of 0.43g/g of the fermentable sugars was obtained. Then, the stillage and the remaining solid materials of the hydrolyzed CWs were anaerobically digested to obtain biogas. In summary, one ton of CWs with 20% dry weight resulted in 39.64l ethanol, 45m(3) methane, 8.9l limonene, and 38.8kg pectin. Copyright 2010 Elsevier Ltd. All rights reserved.

  13. 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.

  14. 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.

  15. Belowground impacts of perennial grass cultivation for sustainable biofuel feedstock production in the tropics

    DOE PAGES

    Sumiyoshi, Yudai; Crow, Susan E.; Litton, Creighton M.; ...

    2016-07-08

    Perennial grasses can sequester soil organic carbon (SOC) in sustainably managed biofuel systems, directly mitigating atmospheric CO2 concentrations while simultaneously generating biomass for renewable energy. Our objective was to quantify SOC accumulation and identify the primary drivers of belowground C dynamics in a zero-tillage production system of tropical perennial C4 grasses grown for biofuel feedstock in Hawaii. Specifically, the quantity, quality, and fate of soil C inputs were determined for eight grass accessions – four varieties each of napier grass and guinea grass. Carbon fluxes (soil CO2 efflux, aboveground net primary productivity, litterfall, total belowground carbon flux, root decay constant),more » C pools (SOC pool and root biomass), and C quality (root chemistry, C and nitrogen concentrations, and ratios) were measured through three harvest cycles following conversion of a fallow field to cultivated perennial grasses. A wide range of SOC accumulation occurred, with both significant species and accession effects. Aboveground biomass yield was greater, and root lignin concentration was lower for napier grass than guinea grass. Structural equation modeling revealed that root lignin concentration was the most important driver of SOC pool: varieties with low root lignin concentration, which was significantly related to rapid root decomposition, accumulated the greatest amount of SOC. Roots with low lignin concentration decomposed rapidly, but the residue and associated microbial biomass/by-products accumulated as SOC. In general, napier grass was better suited for promoting soil C sequestration in this system. Further, high-yielding varieties with low root lignin concentration provided the greatest climate change mitigation potential in a ratoon system. By understanding the factors affecting SOC accumulation and the net greenhouse gas trade-offs within a biofuel production system will aid in crop selection to meet multiple goals toward

  16. 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

  17. 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.

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

    PubMed

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

    2015-04-24

    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.

  19. 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

  20. Sustainability of soil fertility and the use of lignocellulosic crop harvest residues for the production of biofuels: a literature review.

    PubMed

    Reijnders, L

    2013-01-01

    Use of lignocellulosic crop harvest residues for liquid or gaseous biofuel production may impact soil quality, long-term soil fertility and the major determinants of the latter, stocks of soil organic carbon and nutrients. When soil organic carbon stocks of mineral cropland soils are to be maintained, there is scope for the removal of lignocellulosic harvest residues in several systems with much reduced tillage or no tillage. The scope for such removal might be increased when suitably treated residues from the conversion of harvest residues into biofuel are returned to cropland soils. For mineral cropland soils under conventional tillage, the scope for the production of liquid biofuels from harvest residues is likely to be less than in the case of no-till systems. When fertility of cropland soils is to be sustainable, nutrients present in suitably treated biofuel production residues have to be returned to these soils. Apparently, the actual return of carbon and nutrients present in residues of biofuel production from crop harvest residues to arable soils currently predominantly concerns the application of digestates of anaerobic digestion. The effects thereof on soil fertility and quality need further clarification. Further clarification about the effects on soil fertility and quality of chars and of co-products of lignocellulosic ethanol production is also needed.

  1. 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

  2. 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.

  3. 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.

  4. Utilizing Anaerobic Fungi for Two-stage Sugar Extraction and Biofuel Production from Lignocellulosic Biomass.

    PubMed

    Ranganathan, Abhaya; Smith, Olivia P; Youssef, Noha H; Struchtemeyer, Christopher G; Atiyeh, Hasan K; Elshahed, Mostafa S

    2017-01-01

    Lignocellulosic biomass is a vast and underutilized resource for the production of sugars and biofuels. However, the structural complexity of lignocellulosic biomass and the need for multiple pretreatment and enzymatic steps for sugar release renders this process economically challenging. Here, we report a novel approach for direct, single container, exogenous enzyme-free conversion of lignocellulosic biomass to sugars and biofuels using the anaerobic fungal isolate strain C1A. This approach utilizes simple physiological manipulations for timely inhibition and uncoupling of saccharolytic and fermentative capabilities of strain C1A, leading to the accumulation of sugar monomers (glucose and xylose) in the culture medium. The produced sugars, in addition to fungal hyphal lysate, are subsequently converted by Escherichia coli strain K011 to ethanol. Using this approach, we successfully recovered 17.0% (w/w) of alkali-pretreated corn stover (20.0% of its glucan and xylan content) as sugar monomers in the culture media. More importantly, 14.1% of pretreated corn stover (17.1% of glucan and xylan content) was recovered as ethanol at a final concentration of 28.16 mM after the addition of the ethanologenic strain K011. The high ethanol yield obtained is due to its accumulation as a minor fermentation end product by strain C1A during its initial growth phase, the complete conversion of sugars to ethanol by strain K011, and the possible conversion of unspecified substrates in the hyphal lysate of strain C1A to ethanol by strain K011. This study presents a novel, versatile, and exogenous enzyme-free strategy that utilizes a relatively unexplored group of organisms (anaerobic fungi) for direct biofuel production from lignocellulosic biomass.

  5. Utilizing Anaerobic Fungi for Two-stage Sugar Extraction and Biofuel Production from Lignocellulosic Biomass

    PubMed Central

    Ranganathan, Abhaya; Smith, Olivia P.; Youssef, Noha H.; Struchtemeyer, Christopher G.; Atiyeh, Hasan K.; Elshahed, Mostafa S.

    2017-01-01

    Lignocellulosic biomass is a vast and underutilized resource for the production of sugars and biofuels. However, the structural complexity of lignocellulosic biomass and the need for multiple pretreatment and enzymatic steps for sugar release renders this process economically challenging. Here, we report a novel approach for direct, single container, exogenous enzyme-free conversion of lignocellulosic biomass to sugars and biofuels using the anaerobic fungal isolate strain C1A. This approach utilizes simple physiological manipulations for timely inhibition and uncoupling of saccharolytic and fermentative capabilities of strain C1A, leading to the accumulation of sugar monomers (glucose and xylose) in the culture medium. The produced sugars, in addition to fungal hyphal lysate, are subsequently converted by Escherichia coli strain K011 to ethanol. Using this approach, we successfully recovered 17.0% (w/w) of alkali-pretreated corn stover (20.0% of its glucan and xylan content) as sugar monomers in the culture media. More importantly, 14.1% of pretreated corn stover (17.1% of glucan and xylan content) was recovered as ethanol at a final concentration of 28.16 mM after the addition of the ethanologenic strain K011. The high ethanol yield obtained is due to its accumulation as a minor fermentation end product by strain C1A during its initial growth phase, the complete conversion of sugars to ethanol by strain K011, and the possible conversion of unspecified substrates in the hyphal lysate of strain C1A to ethanol by strain K011. This study presents a novel, versatile, and exogenous enzyme-free strategy that utilizes a relatively unexplored group of organisms (anaerobic fungi) for direct biofuel production from lignocellulosic biomass. PMID:28443088

  6. 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.

  7. Projecting future grassland productivity to assess thesustainability of potential biofuel feedstock areas in theGreater Platte River Basin

    USGS Publications Warehouse

    Gu, Yingxin; Wylie, Bruce K.; Boyte, Stephen; Phuyal, Khem P.

    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.

  8. 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.

  9. 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.

  10. 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.

  11. Metabolic and cellular organization in evolutionarily diverse microalgae as related to biofuels production.

    PubMed

    Hildebrand, Mark; Abbriano, Raffaela M; Polle, Juergen E W; Traller, Jesse C; Trentacoste, Emily M; Smith, Sarah R; Davis, Aubrey K

    2013-06-01

    Microalgae are among the most diverse organisms on the planet, and as a result of symbioses and evolutionary selection, the configuration of core metabolic networks is highly varied across distinct algal classes. The differences in photosynthesis, carbon fixation and processing, carbon storage, and the compartmentation of cellular and metabolic processes are substantial and likely to transcend into the efficiency of various steps involved in biofuel molecule production. By highlighting these differences, we hope to provide a framework for comparative analyses to determine the efficiency of the different arrangements or processes. This sets the stage for optimization on the based on information derived from evolutionary selection to diverse algal classes and to synthetic systems.

  12. Metabolic engineering of Cyanobacteria and microalgae for enhanced production of biofuels and high-value products.

    PubMed

    Gomaa, M A; Al-Haj, L; Abed, R M M

    2016-10-01

    A lot of research has been performed on Cyanobacteria and microalgae with the aim to produce numerous biotechnological products. However, native strains have a few shortcomings, like limitations in cultivation, harvesting and product extraction, which prevents reaching optimal production value at lowest costs. Such limitations require the intervention of genetic engineering to produce strains with superior properties. Promising advancements in the cultivation of Cyanobacteria and microalgae have been achieved by improving photosynthetic efficiency through increasing RuBisCO activity and truncation of light-harvesting antennae. Genetic engineering has also contributed to final product extraction by inducing autolysis and product secretory systems, to enable direct product recovery without going through costly extraction steps. In this review, we summarize the different enzymes and pathways that have been targeted thus far for improving cultivation aspects, harvesting and product extraction in Cyanobacteria and microalgae. With synthetic biology advancements, genetically engineered strains can be generated to resolve demanding process issues and achieve economic practicality. This comprehensive overview of gene modifications will be useful to researchers in the field to employ on their strains to increase their yields and improve the economic feasibility of the production process. © 2016 The Society for Applied Microbiology.

  13. Soil carbon change and net energy associated with biofuel production on marginal lands: a regional modeling perspective.

    PubMed

    Bandaru, Varaprasad; Izaurralde, R César; Manowitz, David; Link, Robert; Zhang, Xuesong; Post, Wilfred M

    2013-11-01

    The use of marginal lands for biofuel production has been proposed as a promising solution for meeting biofuel demands while avoiding food-feed-fuel conflicts. However, uncertainty surrounds whether marginal lands can be reliably located, as well as their inherent biofuel potential and the possible environmental impacts. We developed a quantitative approach that integrates high-resolution land cover and land productivity to classify productive croplands and nonarable marginal lands in a nine-county region in southern Michigan. The classified lands were then examined with the spatially explicit modeling framework using the Environmental Policy Integrated Climate (EPIC) model to estimate net energy (NE) and soil organic carbon (SOC) changes associated with the cultivation of different annual and perennial production systems. Simulation results suggest that biofuel production systems underperform on marginal lands when compared to productive croplands. However, we found perennial grasses could perform better than annual crops. Hence, when growing perennial bioenergy crops on marginal lands instead of productive croplands, less additional land (about 0.09 ha per each hectare planted) would be needed to achieve the same NE than if growing annual bioenergy crops (additional 0.17 ha per hectare planted). Miscanthus ( × ) and switchgrass ( L.) can produce 112.43 and 74.61 GJ ha yr NE, respectively, and have the potential to sequester, on average, 0.59 and 0.23 Mg C ha yr SOC, respectively. Notably, simulation results indicate substantial variability of the NE and SOC storage potential across the study region. Thus, although perennial energy crops are promising options for biofuel production on marginal lands, given the large spatial variability, regional- and site-specific management strategies are required for sustainable biofuel production. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  14. Microalgal carbohydrates: an overview of the factors influencing carbohydrates production, and of main bioconversion technologies for production of biofuels.

    PubMed

    Markou, Giorgos; Angelidaki, Irini; Georgakakis, Dimitris

    2012-11-01

    Microalgal biomass seems to be a promising feedstock for biofuel generation. Microalgae have relative high photosynthetic efficiencies, high growth rates, and some species can thrive in brackish water or seawater and wastewater from the food- and agro-industrial sector. Today, the main interest in research is the cultivation of microalgae for lipids production to generate biodiesel. However, there are several other biological or thermochemical conversion technologies, in which microalgal biomass could be used as substrate. However, the high protein content or the low carbohydrate content of the majority of the microalgal species might be a constraint for their possible use in these technologies. Moreover, in the majority of biomass conversion technologies, carbohydrates are the main substrate for production of biofuels. Nevertheless, microalgae biomass composition could be manipulated by several cultivation techniques, such as nutrient starvation or other stressed environmental conditions, which cause the microalgae to accumulate carbohydrates. This paper attempts to give a general overview of techniques that can be used for increasing the microalgal biomass carbohydrate content. In addition, biomass conversion technologies, related to the conversion of carbohydrates into biofuels are discussed.

  15. 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

  16. Acid-Catalyzed Algal Biomass Pretreatment for Integrated Lipid and Carbohydrate-Based Biofuels Production

    SciTech Connect

    Laurens, L. M. L.; Nagle, N.; Davis, R.; Sweeney, N.; Van Wychen, S.; Lowell, A.; Pienkos, P. T.

    2014-11-12

    One of the major challenges associated with algal biofuels production in a biorefinery-type setting is improving biomass utilization in its entirety, increasing the process energetic yields and providing economically viable and scalable co-product concepts. We demonstrate the effectiveness of a novel, integrated technology based on moderate temperatures and low pH to convert the carbohydrates in wet algal biomass to soluble sugars for fermentation, while making lipids more accessible for downstream extraction and leaving a protein-enriched fraction behind. We studied the effect of harvest timing on the conversion yields, using two algal strains; Chlorella and Scenedesmus, generating biomass with distinctive compositional ratios of protein, carbohydrate, and lipids. We found that the late harvest Scenedesmus biomass had the maximum theoretical biofuel potential at 143 gasoline gallon equivalent (GGE) combined fuel yield per dry ton biomass, followed by late harvest Chlorella at 128 GGE per ton. Our experimental data show a clear difference between the two strains, as Scenedesmus was more successfully converted in this process with a demonstrated 97 GGE per ton. Our measurements indicated a release of >90% of the available glucose in the hydrolysate liquors and an extraction and recovery of up to 97% of the fatty acids from wet biomass. Techno-economic analysis for the combined product yields indicates that this process exhibits the potential to improve per-gallon fuel costs by up to 33% compared to a lipids-only process for one strain, Scenedesmus, grown to the mid-point harvest condition.

  17. 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.

  18. Utilization of grasses for potential biofuel production and phytoremediation of heavy metal contaminated soils.

    PubMed

    Balsamo, Ronald A; Kelly, William J; Satrio, Justinus A; Ruiz-Felix, M Nydia; Fetterman, Marisa; Wynn, Rodd; Hagel, Kristen

    2015-01-01

    This research focuses on investigating the use of common biofuel grasses to assess their potential as agents of long-term remediation of contaminated soils using lead as a model heavy metal ion. We present evidence demonstrating that switch grass and Timothy grass may be potentially useful for long-term phytoremediation of heavy metal contaminated soils and describe novel techniques to track and remove contaminants from inception to useful product. Enzymatic digestion and thermochemical approaches are being used to convert this lignocellulosic feedstock into useful product (sugars, ethanol, biocrude oil+biochar). Preliminary studies on enzymatic hydrolysis and fast pyrolysis of the Switchgrass materials that were grown in heavy metal contaminated soil and non-contaminated soils show that the presence of lead in the Switchgrass material feedstock does not adversely affect the outcomes of the conversion processes. These results indicate that the modest levels of contaminant uptake allow these grass species to serve as phytoremediation agents as well as feedstocks for biofuel production in areas degraded by industrial pollution.

  19. Elevated acetyl-CoA by amino acid recycling fuels microalgal neutral lipid accumulation in exponential growth phase for biofuel production.

    PubMed

    Yao, Lina; Shen, Hui; Wang, Nan; Tatlay, Jaspaul; Li, Liang; Tan, Tin Wee; Lee, Yuan Kun

    2017-04-01

    Microalgal neutral lipids [mainly in the form of triacylglycerols (TAGs)], feasible substrates for biofuel, are typically accumulated during the stationary growth phase. To make microalgal biofuels economically competitive with fossil fuels, generating strains that trigger TAG accumulation from the exponential growth phase is a promising biological approach. The regulatory mechanisms to trigger TAG accumulation from the exponential growth phase (TAEP) are important to be uncovered for advancing economic feasibility. Through the inhibition of pyruvate dehydrogenase kinase by sodium dichloroacetate, acetyl-CoA level increased, resulting in TAEP in microalga Dunaliella tertiolecta. We further reported refilling of acetyl-CoA pool through branched-chain amino acid catabolism contributed to an overall sixfold TAEP with marginal compromise (4%) on growth in a TAG-rich D. tertiolecta mutant from targeted screening. Herein, a three-step α loop-integrated metabolic model is introduced to shed lights on the neutral lipid regulatory mechanism. This article provides novel approaches to compress lipid production phase and heightens lipid productivity and photosynthetic carbon capture via enhancing acetyl-CoA level, which would optimize renewable microalgal biofuel to fulfil the demanding fuel market.

  20. 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.

  1. Biorefinery developments for advanced biofuels from a widening array of biomass feedstocks

    USDA-ARS?s Scientific Manuscript database

    When the United States passed the Renewable Fuel Standards (RFS) of 2007 into law it mandated that, by the year 2022, 36 billion gallons of biofuels be produced annually in the U.S. to displace petroleum. This targeted quota, which required that at least half of domestic transportation fuel be “adva...

  2. Review of the harvesting and extraction of advanced biofuels and bioproducts

    Treesearch

    Babette L. Marrone;  Ronald E.  Lacey;  Daniel B. Anderson;  James Bonner;  Jim Coons;  Taraka Dale;  Cara Meghan Downes;  Sandun Fernando;  Christopher  Fuller;  Brian Goodall;  Johnathan E. Holladay;  Kiran Kadam;  Daniel  Kalb;  Wei  Liu;  John B. Mott;  Zivko Nikolov;  Kimberly L. Ogden;  Richard T. Sayre;  Brian G. Trewyn;  José A. Olivares

    2017-01-01

    Energy-efficient and scalable harvesting and lipid extraction processes must be developed in order for the algal biofuels and bioproducts industry to thrive. The major challenge for harvesting is the handling of large volumes of cultivation water to concentrate low amounts of biomass. For lipid extraction, the major energy and cost drivers are associated with...

  3. Raffinate waste as a nitrogen replacement to increase the sustainable use of marine microalgae for biofuel production

    NASA Astrophysics Data System (ADS)

    Swink, C.; Palenik, B.

    2016-02-01

    High lipid content and the ability to be grown on areal non-agricultural land make microalgae one of the few viable candidates for long-term sustainable biofuel production. However, many challenges arise when attempting to scale-up production of algae biofuels at a successful industrial level. A series of growth experiments and toxicity tests were conducted to test the adaptability of 10 different strains of microalgae to grow in cultures containing two types of "raffinate" waste product as a nitrogen replacement. The results of these tests revealed that all strains of microalgae could successfully grow in cultures containing raffinate produced by means of hydrothermal liquefaction, even in bag culture, but not in cultures containing raffinate produced by a lipid trap extraction method. The application of these results is a method of reducing the costs of producing biofuel from marine and freshwater microalgae by creating a more self-sustaining recycling of nutrients from high temperature liquefaction waste.

  4. 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.

  5. 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

    2015-08-07

    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.

  6. 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.

  7. 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.

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

    PubMed

    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

    2011-08-09

    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.

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

    PubMed Central

    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.

    2011-01-01

    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. PMID:21788494

  10. Comparative Proteomics Analysis of Engineered Saccharomyces cerevisiae with Enhanced Biofuel Precursor Production

    PubMed Central

    Tang, Xiaoling; Feng, Huixing; Zhang, Jianhua; Chen, Wei Ning

    2013-01-01

    The yeast Saccharomyces cerevisiae was metabolically modified for enhanced biofuel precursor production by knocking out genes encoding mitochondrial isocitrate dehydrogenase and over-expression of a heterologous ATP-citrate lyase. A comparative iTRAQ-coupled 2D LC-MS/MS analysis was performed to obtain a global overview of ubiquitous protein expression changes in S. cerevisiae engineered strains. More than 300 proteins were identified. Among these proteins, 37 were found differentially expressed in engineered strains and they were classified into specific categories based on their enzyme functions. Most of the proteins involved in glycolytic and pyruvate branch-point pathways were found to be up-regulated and the proteins involved in respiration and glyoxylate pathway were however found to be down-regulated in engineered strains. Moreover, the metabolic modification of S. cerevisiae cells resulted in a number of up-regulated proteins involved in stress response and differentially expressed proteins involved in amino acid metabolism and protein biosynthesis pathways. These LC-MS/MS based proteomics analysis results not only offered extensive information in identifying potential protein-protein interactions, signal pathways and ubiquitous cellular changes elicited by the engineered pathways, but also provided a meaningful biological information platform serving further modification of yeast cells for enhanced biofuel production. PMID:24376832

  11. Optimization of Biofuel and Biochar Production from the Slow Pyrolysis of Biomass

    NASA Astrophysics Data System (ADS)

    Fang, J.; Gao, B.; Nsf Reu in Water Resources

    2010-12-01

    Slow pyrolysis was performed on biomass samples (i.e., energy cane and air potato) to determine the most energy efficient conditions for producing biofuel and biochar. The potential of air potato as a source of fuel and char was also investigated. Dry biomass samples of 10, 15 and 20 g were heated in a reactor at a final temperatures of 300, 450, or 600 °C, and the minimum amount of time required to complete pyrolysis was recorded. Maximum biochar yield was obtained at 300°C for both energy cane and air potato at all masses, and maximum bio-oil yield was obtained at 450°C for all samples. Pyrolysis required the least amount of time at 450°C. Bio-oil yields for air potato were slightly lower than that of energy cane, while biochar yield was slightly higher. Since air potato showed similar product yields to energy cane, this indicates it has potential to be a good feedstock for biofuel and biochar productions.

  12. Characterization of marine microalga, Scenedesmus sp. strain JPCC GA0024 toward biofuel production.

    PubMed

    Matsunaga, Tadashi; Matsumoto, Mitsufumi; Maeda, Yoshiaki; Sugiyama, Hiroshi; Sato, Reiko; Tanaka, Tsuyoshi

    2009-09-01

    A marine microalga, strain JPCC GA0024 was selected as high amount of neutral lipid producers from marine microalgal culture collection toward biofuel production. The strain was tentatively identified as Scenedesmus rubescens by 18S rDNA analysis. The growth of strain JPCC GA0024 was influenced by artificial seawater concentrations. The optimum growth of 0.79 g/l was obtained at 100% artificial seawater. The lipid accumulation reached 73.0% of dry cell weight at 100% artificial seawater without additional nutrients for 11 days. Gas chromatography/mass spectrometry analysis indicates that lipid fraction mainly contained hydrocarbons including mainly hexadecane (C(16) H(34)) and 1-docosene (C(22) H(44)). Furthermore, calorimetric analysis revealed that the energy content of strain JPCC GA0024 was 6,160 kcal/kg (25.8 MJ/kg) of calorific value, which was equivalent to the coal engery. The strain JPCC GA0024, S. rubescens, will become a promising resource that can grow as a dominant species in the seawater for the production of both liquid and solid biofuels.

  13. Fermentation of glycerol and production of valuable chemical and biofuel molecules.

    PubMed

    Mattam, Anu Jose; Clomburg, James M; Gonzalez, Ramon; Yazdani, Syed Shams

    2013-06-01

    Glycerol has attracted the attention of scientific and industrial communities due to its generation in bulk quantities as a byproduct of biofuel industries. With the rapid growth of these industries in recent years, glycerol is frequently treated as a very low-value byproduct or even a waste product with a disposal cost associated to it. Glycerol is not only abundant and inexpensive but also can generate more reducing equivalents than glucose or xylose. This unique characteristic of glycerol offers a tremendous opportunity for its biological conversion to valuable products at higher yield. This review focuses on research efforts to utilize glycerol as a carbon source for the production of a variety of fuels and chemicals by both native and metabolically engineered microorganisms.

  14. Thermodynamic analysis of lignocellulosic biofuel production via a biochemical process: guiding technology selection and research focus.

    PubMed

    Sohel, M Imroz; Jack, Michael W

    2011-02-01

    The aim of this paper is to present an exergy analysis of bioethanol production process from lignocellulosic feedstock via a biochemical process to asses the overall thermodynamic efficiency and identify the main loss processes. The thermodynamic efficiency of the biochemical process was found to be 35% and the major inefficiencies of this process were identified as: the combustion of lignin for process heat and power production and the simultaneous scarification and co-fermentation process accounting for 67% and 27% of the lost exergy, respectively. These results were also compared with a previous analysis of a thermochemical process for producing biofuel. Despite fundamental differences, the biochemical and thermochemical processes considered here had similar levels of thermodynamic efficiency. Process heat and power production was the major contributor to exergy loss in both of the processes. Unlike the thermochemical process, the overall efficiency of the biochemical process largely depends on how the lignin is utilized.

  15. Potential for production of perennial biofuel feedstocks in conservation buffers on the Coastal Plain of Georgia, USA

    USDA-ARS?s Scientific Manuscript database

    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 co...

  16. Production facilities for second generation biofuels in the USA and the EU – current status and future perspectives

    SciTech Connect

    Janssen, Ranier; Turhollow, Jr, Anthony F.; Rutz, Dominik; Mergner, Rita

    2013-10-23

    Second generation biofuel production facilities have been slower to reach large-scale production than was anticipated a few years ago even though in Europe, the Renewable Energy Directive has incentives for, and in the United States there are also financial incentives and, the Energy Independence and Security Act of 2007 has targets for second generation biofuels. There have been a number of facilities that have been cancelled, but starting in 2013 it appears that significant quantities of second generation biofuels will be produced. A variety of conversion processes, thermal and biological, as well as hybrids of the two is being utilized. There will be a variety of fuels ethanol, drop-in fuels (e.g. gasoline, diesel), biodiesel, steam, electricity, bio-oil, sugars, and chemicals; and a variety of feedstocks crop residues, wood, wood wastes, energy crops, waste oils and municipal solid waste (MSW). One approach to reducing the risk of moving from first to second generation biofuel production has been to take incremental steps such as converting the cellulosic part of grains into ethanol in addition to the starch portion. Many of the second generation biofuel facilities are co-located with first generation biofuel production facilities to share infrastructure as well as trade by-products (e.g. excess steam). One of the challenges has been financing, but both private and government sources are being utilized. Private sources include internal corporate funds and debt offerings, and venture capital. Furthermore, government sources include the U.S. federal government, the European Union, European national governments, and state and local governments.

  17. Evaluation of net ecosystem production (2000-2008) for potential grassland biofuel feedstock sites in the Greater Platte River Basin

    NASA Astrophysics Data System (ADS)

    Gu, Y.; Wylie, B. K.; Zhang, L.

    2011-12-01

    Net Ecosystem Production (NEP) is a measure of net carbon accumulation by ecosystems and is an important variable for assessing and understanding the terrestrial carbon cycle and global climate change. We developed a 9-year (2000-2008) time series of NEP data for grasslands within the Great Plains based on flux tower observations, satellite remote sensing, biophysical and climate conditions, and weather data. In this study, we assessed a 9-year time series of NEP in the Greater Platte River Basin to investigate the historical trends of carbon flux (i.e., NEP) for sites possibly suitable for biofuel expansion (productive grasslands) and sites not suitable for biofuel expansion (less productive or degraded grasslands). The suitability of sites was identified using our dynamic modeling of ecosystem performance method. The average annual NEP for sites that were suitable for biofuel feedstock production was from 71 to 169 g C m-2 year-1 during 2000-2008, indicating a strong carbon sink (i.e., more carbon is stored than released) in these areas. The average annual NEP for sites that were not suitable for biofuel feedstock production was from -47 to 69 g C m-2 year-1 during 2000-2008, showing a weak carbon source or a weak carbon sink in these areas. The 9-year accumulated NEP was 200 g C m-2 for the non-suitable areas (a weak carbon sink) and 1166 g C m-2 for the suitable areas (a strong carbon sink). These results demonstrate that our dynamic modeling of ecosystem performance method can identify sites desirable for biofuel feedstock development. Results from this study provide useful information for land managers and decision makers to make optimal land use decisions regarding biofuel feedstock development and sustainability.

  18. 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.

  19. 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 consider