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1

future science group 9ISSN 1759-726910.4155/BFS.11.151 2012 Future Science Ltd Synthetic biology approaches to biofuel production  

E-print Network

approaches to biofuel production Editorial Biofuels (2012) 3(1), 9­12 "...it is important for synthetic there is a tendency, par- ticularly in the algae biofuel space, to prioritize high yields without sufficient regard large enough volumes of biofuels at a low enough cost to make this significant leap in the national

Hasty, Jeff

2

Economics of Current and Future Biofuels  

SciTech Connect

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

Tao, L.; Aden, A.

2009-06-01

3

iBioSeminar: Technical Issues Associated with Future Large-Scale Cellulosic Biofuels Production  

NSDL National Science Digital Library

This presentation describes the rationale for using plant biomass as a source of fuels and presents information about how much energy could be obtained in this way. Examples of the kinds of plants that are likely to be used are presented along with comments on some of the issues, such as losses to disease and effects of various cropping systems on soil quality, that need additional research. The potential for various types of biofuels are compared and some of the technical challenges in production of cellulosic fuels are outlined.

Chris Somerville (Carnegie Institution for Science;)

2007-05-01

4

LIHD biofuels: toward a sustainable future  

E-print Network

LIHD biofuels: toward a sustainable future 115 Linda Wallace, Department of Botany and Microbiology of America www.frontiersinecology.org Will biofuels help to wean the US off of oil, or at least off simple. First, we need to understand what is meant by the term "biofuel". All biofuels are organic

Palmer, Michael W.

5

Cyanobacterial biofuel production.  

PubMed

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

Machado, Iara M P; Atsumi, Shota

2012-11-30

6

Biofuels  

Microsoft Academic Search

It is the cost and abundant availability of raw materials that determine the economic feasibility of biofuel production. Considering\\u000a these constrains, agro-industrial residues may offer cheaper options as raw materials for biofuel production. This chapter\\u000a thus aims at presenting the current status and future directions of biofuel production using both conventional substrates\\u000a and agro-industrial residues as raw materials and critically

Soham Chattopadhyay; Asmita Mukerji; Ramkrishna Sen

7

The Ecology of Algal Biofuel Production  

NSDL National Science Digital Library

Algae offer a promising alternative to terrestrially grown vascular plants as a future source of biofuel (feedstock). Doing so would decrease the worldâs dependence on petroleum fuels, reduce the diversion of edible agricultural crops from food production to energy production, reduce fertilizer use, environmental contamination, and water demands associated with terrestrial biofuel crop cultivation. Combining facilities for the production of algae with sources of domestic or agricultural wastewater would greatly reduce the amount of nitrogen and phosphorus polluting surface waters, and the scientific principles of ecology provide valuable guidance for the design and stable operation of large-scale algal biofuel production facilities.

Val Smith (University of Kansas;)

2011-03-15

8

Spatial Modeling of Geographic Patterns in Biodiversity and Biofuel Production  

E-print Network

Spatial Modeling of Geographic Patterns in Biodiversity and Biofuel Production How can the US of biodiversity. The future of the biofuel industry will depend on public investment and trust that industry for increasing biofuel production have already come under fire because of real and perceived threats

9

Biofuels versus food production: Does biofuels production increase food prices?  

Microsoft Academic Search

Rapidly growing fossil energy consumption in the transport sector in the last two centuries caused problems such as increasing greenhouse gas emissions, growing energy dependency and supply insecurity. One approach to solve these problems could be to increase the use of biofuels.Preferred feedstocks for current 1st generation biofuels production are corn, wheat, sugarcane, soybean, rapeseed and sunflowers. The major problem

Amela Ajanovic

2011-01-01

10

Future of Liquid Biofuels for APEC Economies  

SciTech Connect

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

Milbrandt, A.; Overend, R. P.

2008-05-01

11

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...

12

Production of biofuels from microalgae  

Microsoft Academic Search

The production of biofuels from microalgae, especially biodiesel, has become a topic of great interest in recent years. However,\\u000a many of the published papers do not consider the question of scale up and the feasibility of the various processes to be operated\\u000a at the very large scale required if algal biofuels are to make a meaningful contribution to renewable fuels.

Sophie Fon Sing; Andreas Isdepsky; Michael A. Borowitzka; Navid Reza Moheimani

13

Invitation/Program Technology Watch Day on Future Biofuels  

E-print Network

Invitation/Program Technology Watch Day on Future Biofuels and 4. TMFB International Workshop;International Research Centers Focussing on Future Biofuels are Presenting Their Research Approaches and Current Concerning Future Biofuels DBFZ ­ Deutsches Biomasseforschungszentrum M. Seiffert, F. Mueller-Langer German

14

Impacts of Biofuel Production and Navigation Impediments on Agricultural Transportation and Markets  

E-print Network

This study investigated the impacts of U.S. biofuel production and barge navigation impediments on agricultural transportation and markets. Both past and future impacts of U.S. biofuel production levels mandated by the Renewable Fuel Standards...

Ahmedov, Zafarbek

2013-08-22

15

Biofuels and bio-products derived from  

E-print Network

NEED Biofuels and bio- products derived from lignocellulosic biomass (plant materials) are part improve the energy and carbon efficiencies of biofuels production from a barrel of biomass using chemical and thermal catalytic mechanisms. The Center for Direct Catalytic Conversion of Biomass to Biofuels IMPACT

Ginzel, Matthew

16

Coupling of algal biofuel production with wastewater.  

PubMed

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

Bhatt, Neha Chamoli; Panwar, Amit; Bisht, Tara Singh; Tamta, Sushma

2014-01-01

17

Coupling of Algal Biofuel Production with Wastewater  

PubMed Central

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

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

2014-01-01

18

Defossiling Fuel: How Synthetic Biology Can Transform Biofuel Production  

E-print Network

Defossiling Fuel: How Synthetic Biology Can Transform Biofuel Production David F. Savage , Jeffrey through natural intermediates to final molecule is long, and biofuel production is perhaps the ultimate engineering, economic, political, and environmental realities. Are biofuels sustainable? Consider U

19

Algae biofuels: versatility for the future of bioenergy.  

PubMed

The world continues to increase its energy use, brought about by an expanding population and a desire for a greater standard of living. This energy use coupled with the realization of the impact of carbon dioxide on the climate, has led us to reanalyze the potential of plant-based biofuels. Of the potential sources of biofuels the most efficient producers of biomass are the photosynthetic microalgae and cyanobacteria. These versatile organisms can be used for the production of bioethanol, biodiesel, biohydrogen, and biogas. In fact, one of the most economic methods for algal biofuels production may be the combined biorefinery approach where multiple biofuels are produced from one biomass source. PMID:22104720

Jones, Carla S; Mayfield, Stephen P

2012-06-01

20

Constructed wetlands as biofuel production systems  

NASA Astrophysics Data System (ADS)

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.

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

2012-03-01

21

Is Large-Scale Production of Biofuel Possible?  

NSDL National Science Digital Library

By genetically engineering certain crops, there is potential to produce biofuels commercially. Additionally: 1) Producing biofuels can decrease the worldâs dependence on petroleum fuel. 2)Using biofuels can alleviate environmental contamination from fossil fuel production and use. 3)Farming bioenergy crops could improve rural economies. 4)Establishing sustainability for the biofuel sector can avoid costly production processes.

Miriam Sticklen (Michigan State University;)

2010-07-17

22

RESEARCH ARTICLE A model for improving microbial biofuel production using  

E-print Network

RESEARCH ARTICLE A model for improving microbial biofuel production using a synthetic feedback loop 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

Dunlop, Mary

23

Health impact assessment of liquid biofuel production  

Microsoft Academic Search

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

Rok Fink; Sao Medved

2012-01-01

24

A Realistic Technology and Engineering Assessment of Algae Biofuel Production  

E-print Network

A Realistic Technology and Engineering Assessment of Algae Biofuel Production T of microalgae biofuels production through an analysis of five production scenarios. These scenarios, or cases microalgae biofuel technologies for both oil and biogas production, provides an initial assessment of the US

Quinn, Nigel

25

Global Biofuel Production and Food Security: Implications for Asia Pacific  

E-print Network

Global Biofuel Production and Food Security: Implications for Asia Pacific 56th AARES Annual Conference Fremantle, Western Australia 7-10 February 2012 William T. Coyle #12;Global Biofuel Production and Food Security: Making the Connection --Past analysis and the evidence about biofuels and spiking

26

Metabolic Engineering of oleaginous yeast for the production of biofuels  

E-print Network

The past few years have introduced a flurry of interest over renewable energy sources. Biofuels have gained attention as renewable alternatives to liquid transportation fuels. Microbial platforms for biofuel production ...

Tai, Mitchell

2012-01-01

27

Policy options to support biofuel production.  

PubMed

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. PMID:17846726

Mabee, W E

2007-01-01

28

USDA Biofuels Strategic Production Report June 23, 2010  

E-print Network

USDA Biofuels Strategic Production Report June 23, 2010 1 A USDA Regional Roadmap to Meeting the Biofuels Goals of the Renewable Fuels Standard by 2022 I. INTRODUCTION The U.S. Department of Agriculture. The strategy targets barriers to the development of a successful biofuels market that will achieve, or surpass

29

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

SciTech Connect

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).

Kevin L Kenney

2011-09-01

30

Challenges in Engineering Microbes for Biofuels Production  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. 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.

Gregory Stephanopoulos (Massachusetts Institute of Technology;Department of Chemical Engineering)

2007-02-09

31

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

NASA Astrophysics Data System (ADS)

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

Demissie, Y. K.

2013-12-01

32

Limitation of Biofuel Production in Europe from the Forest Market  

NASA Astrophysics Data System (ADS)

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.

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

2013-04-01

33

Environmental indicators for sustainable production of algal biofuels  

SciTech Connect

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

Efroymson, Rebecca Ann [ORNL; Dale, Virginia H [ORNL

2014-01-01

34

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)...

35

An overview of algae biofuel production and potential environmental impact.  

PubMed

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

Menetrez, Marc Y

2012-07-01

36

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

Code of Federal Regulations, 2012 CFR

...Succession and loss of control of advanced biofuel facilities and production. 4288.137...AGRICULTURE PAYMENT PROGRAMS Advanced Biofuel Payment Program General Provisions ...Succession and loss of control of advanced biofuel facilities and production. (a)...

2012-01-01

37

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

...Succession and loss of control of advanced biofuel facilities and production. 4288.137...AGRICULTURE PAYMENT PROGRAMS Advanced Biofuel Payment Program General Provisions Payment...Succession and loss of control of advanced biofuel facilities and production. (a)...

2014-01-01

38

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

Code of Federal Regulations, 2013 CFR

...Succession and loss of control of advanced biofuel facilities and production. 4288.137...AGRICULTURE PAYMENT PROGRAMS Advanced Biofuel Payment Program General Provisions ...Succession and loss of control of advanced biofuel facilities and production. (a)...

2013-01-01

39

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

Federal Register 2010, 2011, 2012, 2013

...Production Incentives for Cellulosic Biofuels: Notice of Program Intent AGENCY: Office...EPAct 2005). Through this notice, biofuels producers and other interested parties...Production Incentives for Cellulosic Biofuels; Reverse Auction Procedures and...

2010-07-22

40

Biofuels  

NASA Video Gallery

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...

41

High biofuel production of Botryococcus braunii using optimized cultivation strategies  

E-print Network

and algae biomass increases rapidly as well as the biofuelbiofuel obtained from microalgae right now, scientists are searching for other valuable products from algaeand biofuel productivity. Currently all the culture media use a single source of nitrogen to feed algae,

Yu, Wei

2014-01-01

42

Next-generation biomass feedstocks for biofuel production  

PubMed Central

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

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

2008-01-01

43

Properties of Danish biofuels and the requirements for power production  

Microsoft Academic Search

Owing to government demand, ELSAM (the power pool of the western part of Denmark) obliged to utilize large amounts of biofuels for power production.Straw and wood chips are the most abundant biofuels in Denmark, and an overview of fuel composition in comparison with coal is given. The high content of potassium and chlorine in straw causes a number of serious

Bo Sander

1997-01-01

44

Biofuel Production in Microorganisms: From Phototrophs to Obligate Anaerobes  

NSDL National Science Digital Library

The Advanced Technology Environmental and Energy Center (ATEEC) provides this presentation on biofuel production in microorganisms. The material would be useful in an advanced course on biofuel technology; it includes advanced biological concepts and includes an in depth analysis of the issue. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

Eckert, Carrie

2011-03-08

45

The potential of sustainable algal biofuel production using wastewater resources  

Microsoft Academic Search

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

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

2011-01-01

46

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

PubMed

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

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

2014-02-01

47

High biofuel production of Botryococcus braunii using optimized cultivation strategies.  

E-print Network

??This thesis describes how using a heterotrophy-recovery-autotrophy route (called the green cycle) for the cultivation of Botryococcus braunii results in high biofuel production. Our experiments (more)

Yu, Wei

2014-01-01

48

White paper report from working groups attending the international conference on research and educational opportunities in bio-fuel crop production  

Microsoft Academic Search

A conference on current research and educational programs in production of crops for bio-fuel was sponsored and organized by the EARTH University and the University of Florida in November, 2008. The meeting addressed current research on crops for bio-fuel production with discussions of research alternatives for future crop production systems, land use issues, ethics of food vs. fuel production, and

K. T. Morgan; R. A. Gilbert; Z. A. Helsel; L. Buacum; R. Leon; J. Perret

2010-01-01

49

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

SciTech Connect

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

Sastri, B.; Lee, A.

2008-09-15

50

Slab waveguide photobioreactors for microalgae based biofuel production{{ Erica Eunjung Jung,a  

E-print Network

Slab waveguide photobioreactors for microalgae based biofuel production{{ Erica Eunjung Jung are a promising feedstock for sustainable biofuel production. At present, however, there are a number to substantial interest in increasing biofuel production. Biofuels can be produced from a number of different

Erickson, David

51

Advanced biofuel production by the yeast Saccharomyces cerevisiae.  

PubMed

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. PMID:23628723

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

2013-06-01

52

Questions, Answers and Clarifications Commercial Scale Advanced Biofuels Production Facilities Solicitation  

E-print Network

Questions, Answers and Clarifications Commercial Scale Advanced Biofuels Production Facilities biofuels production facility? A.1 An existing biofuels facility is an existing facility that, as of the application due date of PON-13-601, produces (or did produce) biofuels in California. Q.2 Must an eligible

53

Challenges in Engineering Microbes for Biofuels Production  

Microsoft Academic Search

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

Gregory Stephanopoulos

2007-01-01

54

Enzymatic deconstruction of xylan for biofuel production  

PubMed Central

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

DODD, DYLAN; CANN, ISAAC K. O.

2010-01-01

55

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

Microsoft Academic Search

This study by the U.S. Department of Energy (DOE) estimates the worldwide potential to produce biofuels including biofuels for export. It was undertaken to improve our understanding of the potential for imported biofuels to satisfy the requirements of Title II of the 2007 Energy Independence and Security Act (EISA) in the coming decades. Many other countries biofuels production and policies

B. Sastri; A. Lee

2008-01-01

56

The economic feasibility of sugar beet biofuel production in central North Dakota  

Microsoft Academic Search

This study examines the financial feasibility of producing ethanol biofuel from sugar beets in central North Dakota. Under the Energy Independence and Security Act (EISA) of 2007, biofuel from sugar beets uniquely qualifies as an advanced biofuel. EISA mandates production of 21 billion gallons of advanced biofuels annually by 2022. A stochastic simulation financial model was calibrated with irrigated sugar

Thein A. Maung; Cole R. Gustafson

2011-01-01

57

The Economic Feasibility of Sugarbeet Biofuel Production in Central North Dakota  

Microsoft Academic Search

This study examines the financial feasibility of producing ethanol biofuel from sugar beets in central North Dakota. Under the Energy Independence and Security Act (EISA) of 2007, biofuel from sugar beets uniquely qualifies as an advanced biofuel. EISA mandates production of 15 billion gallons of advanced biofuels annually by 2022. A stochastic simulation financial model was calibrated with irrigated sugar

Thein A. Maung; Cole R. Gustafson

2010-01-01

58

The Economic Feasibility of Energy Sugar Beet Biofuel Production in Central North Dakota  

Microsoft Academic Search

This study examines the financial feasibility of producing ethanol biofuel from sugar beets in central North Dakota. Under the Energy Independence and Security Act (EISA) of 2007, biofuel from sugar beets uniquely qualifies as an advanced biofuel. EISA mandates production of 15 billion gallons of advanced biofuels annually by 2022. A stochastic simulation financial model was calibrated with irrigated sugar

Thein A. Maung; Cole R. Gustafson

2010-01-01

59

Bioeconomic Sustainability of Cellulosic Biofuel Production on Marginal Lands  

ERIC Educational Resources Information Center

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

Gutierrez, Andrew Paul; Ponti, Luigi

2009-01-01

60

Fueling the future: Evaluating the sustainability of biofuels  

NSDL National Science Digital Library

In this activity, students consider the impact and sustainability of use of different classes of biofuels on the economy, the environment, and society. Students also learn about bioelectricity and how converting biomass to electricity may be the more efficient way to fuel cars in the 21st century.

Haine, Dana; University Of North Carolina, School O.

61

Economic analysis of harvesting corn cobs for biofuel production  

Microsoft Academic Search

Cellulosic biofuels may be on the brink of commercial production. Corn residues are one source that has been evaluated by several researchers. However, another resource would be just the corn cobs, and little work has been done on cobs alone. ^ This research analyzes the per ton payment farmers need to receive in order to harvest cobs. To achieve the

Matthew J Erickson

2010-01-01

62

Microalgae production as a biofuel feedstock: risks and challenges  

Microsoft Academic Search

From a sustainability perspective, the potential risks associated with microalgae production for biofuel extraction will be investigated in this paper, including the environmental, economic, social and cultural dimensions. Environmentally, four main concerns are mapped out: first, there are potential water safety risks, such as water resource abuse, water pollution and groundwater recharge deficiency; second, unreasonable construction will lead to land-use

Liandong Zhu; Tarja Ketola

2012-01-01

63

Microalgae production as a biofuel feedstock: risks and challenges  

Microsoft Academic Search

From a sustainability perspective, the potential risks associated with microalgae production for biofuel extraction will be investigated in this paper, including the environmental, economic, social and cultural dimensions. Environmentally, four main concerns are mapped out: first, there are potential water safety risks, such as water resource abuse, water pollution and groundwater recharge deficiency; second, unreasonable construction will lead to land-use

Liandong Zhu; Tarja Ketola

2011-01-01

64

Biofuel production by in vitro synthetic enzymatic pathway biotransformation.  

PubMed

Cell-free synthetic pathway biotransformation (SyPaB) is the implementation of complicated biochemical reactions by in vitro assembling a number of enzymes or their complexes and coenzymes. Assembly of numerous enzymes without cellular membrane, gene regulation, or undesired pathway can circumvent some of the obstacles to modifying living microorganisms. Several synthetic pathways for the production of liquid biofuels--alcohols and hydrocarbon precursors (polyols) as well as gaseous biofuel--hydrogen have been presented. The present constraints to SyPaB include the lack of stable enzymes as Lego-like building blocks, the different optimal reaction conditions for individual enzyme, and the use of costly labile coenzymes. It is expected that high-yield SyPaB will be an important platform for producing low-cost biofuels and biochemicals. PMID:20566280

Zhang, Y-H Percival; Sun, Jibin; Zhong, Jian-Jiang

2010-10-01

65

Influence of biofuel crops on mosquito production and oviposition site selection  

E-print Network

Influence of biofuel crops on mosquito production and oviposition site selection E P H A N T U S J of biofuels production may cause unintended land-use changes and potentially alter ecosystem services and Miscanthus) biofuel crops on production and oviposition site selection by two vector mosquitoes, the yellow

Allan, Brian

66

Potential Direct and Indirect Effects of Global Cellulosic Biofuel Production on Greenhouse  

E-print Network

Potential Direct and Indirect Effects of Global Cellulosic Biofuel Production on Greenhouse Gas on recycled paper #12;1 Potential Direct and Indirect Effects of Global Cellulosic Biofuel Production. Melillo*, John M. Reilly§ , and Sergey Paltsev§ Abstract The production of cellulosic biofuels may have

67

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

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

68

Wastewater treatment high rate algal ponds for biofuel production.  

PubMed

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. PMID:20674341

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

2011-01-01

69

Tappable Pine Trees: Commercial Production of Terpene Biofuels in Pine  

SciTech Connect

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 woodterpenes 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.

None

2012-01-01

70

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes  

E-print Network

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversity-fold expansion of biofuel production (4), which will likely drive further expansion of corn area

Landis, Doug

71

Photobioreactor Design for Commercial Biofuel Production from Microalgae Aditya M. Kunjapur* and R. Bruce Eldridge  

E-print Network

Photobioreactor Design for Commercial Biofuel Production from Microalgae Aditya M. Kunjapur* and R This review paper describes systems used to cultivate microalgae for biofuel production. It addresses general of biofuel. This paper also highlights the concept of combining open and closed systems and concludes

Eldridge, R. Bruce

72

Comparative genomics of xylose-fermenting fungi for enhanced biofuel production  

E-print Network

Comparative genomics of xylose-fermenting fungi for enhanced biofuel production Dana J. Wohlbacha for review February 24, 2011) Cellulosic biomass is an abundant and underused substrate for biofuel creates specific challenges for microbial biofuel production from cellulosic material. Although engineered

Gasch, Audrey P.

73

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

SciTech Connect

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 bacteriaincreasing the organisms access to its energy source and improving the efficiency of the biofuel-creation process. Finally, LBNL is tethering electrocatalysts to the bacterias 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.

None

2010-08-01

74

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

PubMed Central

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

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

2008-01-01

75

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

SciTech Connect

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.

Hemme, Christopher [University of Oklahoma; Mouttaki, Housna [University of Oklahoma; Lee, Yong-Jin [University of Oklahoma, Norman; Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Copeland, A [U.S. Department of Energy, Joint Genome Institute; Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Glavina Del Rio, Tijana [U.S. Department of Energy, Joint Genome Institute; Tice, Hope [U.S. Department of Energy, Joint Genome Institute; Saunders, Elizabeth H [Los Alamos National Laboratory (LANL); Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Han, Cliff [Los Alamos National Laboratory (LANL); Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Mikhailova, Natalia [U.S. Department of Energy, Joint Genome Institute; He, Zhili [University of Oklahoma; Wu, Liyou [University of Oklahoma, Norman; Van Nostrand, Joy [University of Oklahoma, Norman; Henrissat, Bernard [Universite d'Aix-Marseille I & II; HE, Qiang [ORNL; Lawson, Paul A. [University of Oklahoma, Norman; Tanner, Ralph S. [University of Oklahoma, Norman; Lynd, Lee R [Thayer School of Engineering at Dartmouth; Wiegel, Juergen [University of Georgia, Athens, GA; Fields, Dr. Matthew Wayne [Montana State University; Arkin, Adam [Lawrence Berkeley National Laboratory (LBNL); Schadt, Christopher Warren [ORNL; Stevenson, Bradley S. [University of Oklahoma, Norman; McInerney, Michael J. [University of Oklahoma, Norman; Yang, Yunfeng [ORNL; Dong, Hailiang [Miami University, Oxford, OH; Xing, Defeng [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology; Ren, Nanqi [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology; Wang, Aijie [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology; Ding, Shi-You [National Energy Renewable Laboratory; Himmel, Michael E [National Renewable Energy Laboratory (NREL); Taghavi, Safiyh [Brookhaven National Laboratory (BNL)/U.S. Department of Energy; Van Der Lelie, Daniel [Brookhaven National Laboratory (BNL); Rubin, Edward M. [U.S. Department of Energy, Joint Genome Institute; Zhou, Jizhong [University of Oklahoma

2010-01-01

76

Genetic engineering of algae for enhanced biofuel production.  

PubMed

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. PMID:20139239

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

2010-04-01

77

Genetic Engineering of Algae for Enhanced Biofuel Production ?  

PubMed Central

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

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

2010-01-01

78

Multiphase Flow Modeling of Biofuel Production Processes  

Microsoft Academic Search

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

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

2011-01-01

79

Comparative cost analysis of algal oil production for biofuels  

Microsoft Academic Search

Economic analysis is an essential evaluation for considering feasibility and viability of large-scale, photoautotrophic algae-based, biofuel production. Thus far, economic analysis has been conducted on a scenario-by-scenario basis which does not allow for cross-comparisons. In 2008, a comparative study was carried out using a cross-section of cost analyses consisting of 12 public studies. The resulting triacylglyceride cost had a spread

Amy Sun; Ryan Davis; Meghan Starbuck; Ami Ben-Amotz; Ron Pate; Philip T. Pienkos

2011-01-01

80

Piedmont Biofuels Homepage  

NSDL National Science Digital Library

The Piedmont Biofuels homepage provides access to information about small industrial production of biodiesel, biofuels educational programs at Cental Carolina Community College, and volunteer opportunities in biofuels.

2006-10-31

81

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

E-print Network

REVIEW AND SYNTHESIS Industrial-strength ecology: trade-offs and opportunities in algal biofuel biofuel technologies approaches these problems from a cellular or genetic perspective, attempting either for biofuel productivity and resilience. We argue that a community engineering approach that manages

82

Life-Cycle Greenhouse Gas and Energy Analyses of Algae Biofuels Production  

E-print Network

Life-Cycle Greenhouse Gas and Energy Analyses of Algae Biofuels Production Transportation Energy The Issue Algae biofuels directly address the Energy Commission's Public Interest Energy Research the sustainability of algae biofuels suggests that the lifecycle performance of these fuels is a critical

83

Alternative and Renewable fuels and Vehicle Technology Program Subject Area: Biofuels production Facilities  

E-print Network

Alternative and Renewable fuels and Vehicle Technology Program Subject Area: Biofuels production: Commercial Facilities · Applicant's Legal Name: Yokayo Biofuels, Inc. · Name of project: A Catalyst for Success · Project Description: Yokayo Biofuels, an industry veteran with over 10 years experience

84

Diagram of the Biofuel Production Process (SPORL -Alcohol Production):Introduction: The Northwest Advanced Renewables Alliance (NARA) is an organization  

E-print Network

Diagram of the Biofuel Production Process (SPORL - Alcohol Production):Introduction: The Northwest Advanced Renewables Alliance (NARA) is an organization that aims to create a sustainable aviation biofuels to determine the atmospheric emissions and emission sources that may be released from proposed NARA biofuels

Collins, Gary S.

85

Biofuel Production in Italy and Europe: Benefits and Costs, in the Light of the Present European Union Biofuel Policy  

Microsoft Academic Search

We present and critically evaluate in this paper biofuel production options in Italy, in order to provide the reader with\\u000a the order of magnitudes of the performance indicators involved. Also, we discuss biofuel viability and desirability at the\\u000a European level, according to the recent EU regulations and energy policy decisions.\\u000a \\u000a Fuels from biomass are most often proposed as substitutes for

Sergio Ulgiati; Daniela Russi; Marco Raugei

86

Microalgal Triacylglycerols as Feedstocks for Biofuel Production: Perspectives and Advances  

SciTech Connect

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.

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

2008-01-01

87

National Microalgae Biofuel Production Potential and Resource Demand  

SciTech Connect

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.

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

2011-04-14

88

Catalytic pyrolysis of biomass for biofuels production  

Microsoft Academic Search

Fast pyrolysis bio-oils currently produced in demonstration and semi-commercial plants have potential as a fuel for stationary power production using boilers or turbines but they require significant modification to become an acceptable transportation fuel. Catalytic upgrading of pyrolysis vapors using zeolites is a potentially promising method for removing oxygen from organic compounds and converting them to hydrocarbons. This work evaluated

Richard French; Stefan Czernik

2010-01-01

89

Biofuel Production Initiative at Claflin University.  

National Technical Information Service (NTIS)

Fossil fuel is a non-renewable resource that causes environmental hazards such as global warming and the release of toxic gases. Most importantly, while oil production reached its peak in 2005, the demand for oil worldwide will double in the next two deca...

K. Chowdhury

2011-01-01

90

National microalgae biofuel production potential and resource demand  

NASA Astrophysics Data System (ADS)

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.

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

2011-03-01

91

PETRO: Higher Productivity Crops for Biofuels  

SciTech Connect

PETRO Project: The 10 projects that comprise ARPA-Es 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.

None

2012-01-01

92

Biofuels Feedstock Development Program: 1995 activities and future directions  

SciTech Connect

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

Ferrell, J.E.; Wright, L.L.; Tuskan, G.A. [Oak Ridge National Laboratory, TN (United States)] [and others

1995-12-31

93

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

PubMed

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

Vuichard, Nicolas; Ciais, Philippe; Wolf, Adam

2009-11-15

94

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

SciTech Connect

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.

Zhang, X [University of Maryland; Izaurralde, R. C. [University of Maryland; Manowitz, D. [University of Maryland; West, T. O. [University of Maryland; Thomson, A. M. [University of Maryland; Post, Wilfred M [ORNL; Bandaru, Vara Prasad [ORNL; Nichols, Jeff [ORNL; Williams, J. [AgriLIFE, Temple, TX

2010-10-01

95

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

SciTech Connect

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.

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

96

Integrated biorefineries with engineered microbes and high-value co-products for profitable biofuels production  

Microsoft Academic Search

Corn-based fuel ethanol production processes provide several advantages which could be synergistically applied to overcome\\u000a limitations of biofuel processes based on lignocellulose. These include resources such as equipment, manpower, nutrients,\\u000a water, and heat. The fact that several demonstration-scale biomass ethanol processes are using corn as a platform supports\\u000a this viewpoint. This report summarizes the advantages of first-generation corn-based biofuel processes

W. R. Gibbons; S. R. Hughes

2009-01-01

97

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

Microsoft Academic Search

\\u000a Corn-based fuel ethanol production processes provide several advantages which could be synergistically applied to overcome\\u000a limitations of biofuel processes based on lignocellulose. These include resources such as equipment, manpower, nutrients,\\u000a water, and heat. The fact that several demonstration-scale biomass ethanol processes are using corn as a platform supports\\u000a this viewpoint. This report summarizes the advantages of first-generation corn-based biofuel processes

William Gibbons; Stephen Hughes

98

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

SciTech Connect

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.

Dunlop, Mary; Keasling, Jay; Mukhopadhyay, Aindrila

2011-07-14

99

The impact of extreme drought on the biofuel feedstock production  

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

100

Production of advanced biofuels in engineered E. coli.  

PubMed

Commercial fermentation processes have long taken advantage of the synthetic power of living systems to rapidly and efficiently transform simple carbon sources into complex molecules. In this regard, the ability of yeasts to produce ethanol from glucose at exceptionally high yields has served as a key feature in its use as a fuel, but is also limited by the poor molecular properties of ethanol as a fuel such as high water miscibility and low energy density. Advances in metabolic engineering and synthetic biology allow us to begin constructing new high-flux pathways for production of next generation biofuels that are key to building a sustainable pipeline for liquid transportation fuels. PMID:23659832

Wen, Miao; Bond-Watts, Brooks B; Chang, Michelle C Y

2013-06-01

101

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

Microsoft Academic Search

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

Logan Christenson; Ronald Sims

2011-01-01

102

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

NASA Astrophysics Data System (ADS)

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

Gillon, Sean Thomas

103

Grazing Strategies for Beef Production Escalating energy costs and alternative cropping systems for biofuels production have  

E-print Network

Grazing Strategies for Beef Production Escalating energy costs and alternative cropping systems for biofuels production have dramatically increased costs of fertilizer, seed, and feed grains. These increased pri- mary costs for beef production have created a shift in models previously used to man- age both

104

Biofuel Production Initiative at Claflin University Final Report  

SciTech Connect

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

Chowdhury, Kamal

2011-07-20

105

Biofuels for the future Biocoal: Full steam ahead  

E-print Network

question we hear at grocery stores can sometimes divide families and friends. Some people may cite the amount of energy and water used for production of a paper bag as they chose the plastic option. Others to the question is easy: bring your own bag. (Assuming one doesn't leave their reusable bags at home!) But, what

Netoff, Theoden

106

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.

107

Biofuels in the US: Today and in the Future  

Microsoft Academic Search

By 2015 the US corn market can be expected to support 15B gallons of ethanol from corn grain, utilizing less than a quarter of overall US corn production and leaving a net of 12.3 billion bushels (B bu) of corn available for feed, food, and export marketsup 3.0B bu from 2006 and 0.9B bu from 2007. Unlike the speculation that

Martha A. Schlicher

2008-01-01

108

Resource demand implications for US algae biofuels production scale-up  

Microsoft Academic Search

Photosynthetic microalgae with the potential for high biomass and oil productivities have long been viewed as a promising class of feedstock for biofuels to displace petroleum-based transportation fuels. Algae offer the additional benefits of potentially being produced without using high-value arable land and fresh water, thereby reducing the competition for those resources between expanding biofuels production and conventional agriculture. Algae

Ron Pate; Geoff Klise; Ben Wu

2011-01-01

109

Cultivation of algae with indigenous species Potentials for regional biofuel production  

Microsoft Academic Search

The massive need for sustainable energy has led to an increased interest in new energy resources, such as production of algae, for use as biofuel. There are advantages to using algae, for example, land use is much less than in terrestrial biofuel production, and several algae species can double their mass in 1day under optimized conditions. Most algae are phototrophs

M. Odlare; E. Nehrenheim; E. Thorin; M. Gavare; M. Grube

2011-01-01

110

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

Microsoft Academic Search

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

Michael H. Huesemann; John R. Benemann

2009-01-01

111

Life cycle and landscape impacts of biofuel production  

NASA Astrophysics Data System (ADS)

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.

Hill, J.

2012-12-01

112

Technical Feasibility Study on Biofuels Production from Pyrolysis of Nannochloropsis oculata and Algal Bio-oil Upgrading  

E-print Network

Increasing environmental concerns over greenhouse gas emissions, depleting petroleum reserves and rising oil prices has stimulated interest on biofuels production from biomass sources. This study explored on biofuels production from pyrolysis...

Maguyon, Monet

2013-12-02

113

Your World Magazine - Biofuels: Energy for Your Future  

SciTech Connect

Policymakers have been talking for years about measures to cut back how much petroleum we use. Interest has spiked recently, with government and private companies coming together to push forward scientific research and development of alternative fuel products such as ethanol. Biotechnology is helping make alternative energy sources easier - and more affordable - to produce. Most of the world's energy needs are met with oil and natural gas, which come from fossil fuel. No one knows how long the supply can last. Biobased fuels come from natural sources that can be replaced quickly. Along with corn, there are many other grains, grasses, trees, and even agricultural wastes being investigated for their usefulness and environmental friendliness as alternative fuel sources. Careers in this emerging new field emphasize chemistry and engineering. Look into it for a potential career - it's definitely a job full of energy.

Biotechnology Institute

2006-10-01

114

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

PubMed Central

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

2014-01-01

115

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

SciTech Connect

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

Oladosu, Gbadebo A [ORNL] [ORNL; Kline, Keith L [ORNL] [ORNL

2013-01-01

116

Optimization of light use efficiency for biofuel production in algae.  

PubMed

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

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

2013-12-01

117

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

SciTech Connect

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

Wang, M.; Huo, H.; Arora, S. (Energy Systems)

2011-01-01

118

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

Microsoft Academic Search

Long-term sustainability of a biofuel economy necessitates environmentally friendly biofuel production systems. We describe a biophysical modeling framework developed to understand and quantify the environmental value and impact (e.g. water balance, nutrients balance, carbon balance, and soil quality) of different biomass cropping systems. This modeling framework consists of three major components: 1) a Geographic Information System (GIS) based data processing

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

2009-01-01

119

Use of tamarisk as a potential feedstock for biofuel production.  

SciTech Connect

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.

Sun, Amy Cha-Tien; Norman, Kirsten

2011-01-01

120

Plant genetic engineering for biofuel production: towards affordable cellulosic ethanol  

Microsoft Academic Search

Biofuels provide a potential route to avoiding the global political instability and environmental issues that arise from reliance on petroleum. Currently, most biofuel is in the form of ethanol generated from starch or sugar, but this can meet only a limited fraction of global fuel requirements. Conversion of cellulosic biomass, which is both abundant and renewable, is a promising alternative.

Mariam B. Sticklen

2008-01-01

121

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

EPA Science Inventory

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

122

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

NASA Astrophysics Data System (ADS)

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

Stanzel, Philipp; Kling, Harald; Nicholson, Kit

2014-05-01

123

The impact of first-generation biofuels on the depletion of the global phosphorus reserve.  

PubMed

The large majority of biofuels to date is "first-generation" biofuel made from agricultural commodities. All first-generation biofuel production systems require phosphorus (P) fertilization. P is an essential plant nutrient, yet global reserves are finite. We argue that committing scarce P to biofuel production involves a trade-off between climate change mitigation and future food production. We examine biofuel production from seven types of feedstock, and find that biofuels at present consume around 2% of the global inorganic P fertilizer production. For all examined biofuels, with the possible exception of sugarcane, the contribution to P depletion exceeds the contribution to mitigating climate change. The relative benefits of biofuels can be increased through enhanced recycling of P, but high increases in P efficiency are required to balance climate change mitigation and P depletion impacts. We conclude that, with the current production systems, the production of first-generation biofuels compromises food production in the future. PMID:22351599

Hein, Lars; Leemans, Rik

2012-06-01

124

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

SciTech Connect

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

Huesemann, Michael H.; Benemann, John R.

2009-12-31

125

Environmental Costs and Benefits of Transportation Biofuel Production from Food and Lignocellulose-Based Energy Crops: A Review  

Microsoft Academic Search

Transportation biofuel production in the United States is currently dominated by ethanol from the grain of maize and, to a\\u000a much lesser extent, biodiesel from soybeans. Although using these biofuels avoids many of the environmentally detrimental\\u000a aspects of petroleum-based fossil fuels, biofuel production has its own environmental costs, largely related to fossil fuel\\u000a use in converting crops to biofuels and

Jason Hill

126

Environmental costs and benefits of transportation biofuel production from food- and lignocellulose-based energy crops. A review  

Microsoft Academic Search

Transportation biofuel production in the United States is currently dominated by ethanol from the grain of maize and, to a\\u000a much lesser extent, biodiesel from soybeans. Although using these biofuels avoids many of the environmentally detrimental\\u000a aspects of petroleum-based fossil fuels, biofuel production has its own environmental costs, largely related to fossil fuel\\u000a use in converting crops to biofuels and

Jason Hill

2007-01-01

127

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

SciTech Connect

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

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

2008-08-01

128

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

SciTech Connect

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.

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

2009-12-02

129

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

PubMed

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

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

2010-01-01

130

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

PubMed

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

Demissie, Yonas; Yan, Eugene; Wu, May

2012-08-21

131

future science group 5ISSN 1759-726910.4155/BFS.12.76 2013 Future Science Ltd Special FocuS: advanced FeedStockS For advanced bioFuelS  

E-print Network

future science group 5ISSN 1759-726910.4155/BFS.12.76 � 2013 Future Science Ltd Special Focu biofuel plant [3]. Accounting for the US Department of Transportation's legal weight limit of 21.8 tons. For reprint orders, please contact reprints@future-science.com #12;Biofuels (2013) 4(1) future science group6

132

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

E-print Network

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 ...

Caiazzo, Fabio

133

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

EPA Science Inventory

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

134

Computer simulations suggest a new strategy to design enhanced enzymes for biofuels production.  

E-print Network

Computer simulations suggest a new strategy to design enhanced enzymes for biofuels production. Large-scale computer simulations predict that the addition of glycosylation on carbohydrate Energy Laboratory (NREL) used computer simulation to predict that adding glycosylation

135

Second generation biofuels: Economics and policies  

Microsoft Academic Search

This study reviews economics of production of second generation biofuels from various feedstocks, including crop and wood\\/forestry residues, lignocellulosic energy crops, jatropha, and algae. The study indicates that while second generation biofuels could significantly contribute to the future energy supply mix, cost is a major barrier to its commercial production in the near to medium term. Depending upon type of

Miguel A. Carriquiry; Xiaodong Du; Govinda R. Timilsina

2011-01-01

136

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

NASA Astrophysics Data System (ADS)

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

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

2011-09-01

137

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

SciTech Connect

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 MITs biofuel-production system.

None

2010-07-15

138

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

PubMed

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. PMID:17874759

Mattison, Elizabeth H A; Norris, Ken

2007-08-15

139

Sustainability standards for biofuels : analyses of the current standards and recommendations of the future direction  

E-print Network

Past decades have seen development and expansion of biofuels industry around the world thanks to the environmental and economic contribution that biofuels have promised. As more and more people became concerned about the ...

Lee, Leebong

2014-01-01

140

Energy Policy 36 (2008) 15771583 Towards a sustainably certifiable futures contract for biofuels  

E-print Network

for biofuels John A. Mathews? Macquarie Graduate School of Management, Macquarie University, Sydney, NSW 2109 are biofuels to be certified as produced in a sustainable and responsible fashion? In the global debate over through which a global biofuels market is being created. In this contribution, I propose a solution

141

Future prospects for production of methanol and hydrogen from biomass  

NASA Astrophysics Data System (ADS)

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

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

142

Reclaimed Water and Secondary Wastewater as Alternative Growing Media for Green Algae for Biofuel Production  

Microsoft Academic Search

The microalga Botryococcus braunii is one of many photosynthtic algae species being investigated as renewable feedstocks for production of biofuels. One key advantage of algae as biofuel feedstock, in view of the growing scarcity of fresh water worldwide, is the potential of algae to grow in low-quality water, including in the nutrient-containing effluents from wastewater-treatment plants. Indeed, algae could also

Sara S. Kuwahara; Joel L. Cuello

143

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

PubMed

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

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

2014-02-01

144

Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France and  

E-print Network

.forsell@mines-paristech.fr Tel: + 33 (0)4 97 15 70 78 Abstract In the context of mitigating climate change and increase energy change and increase energy security, the European Union (EU) has set the following targets: by 20201 Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France

Boyer, Edmond

145

Methodology for calculation of carbon balances for biofuel crops production  

NASA Astrophysics Data System (ADS)

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

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

2012-04-01

146

Lifecycle Assessment of Biofuel Production from Wood Pyrolysis Technology  

ERIC Educational Resources Information Center

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

Manyele, S. V.

2007-01-01

147

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

Microsoft Academic Search

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

Katrina Lea Christiansen

2011-01-01

148

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

NASA Astrophysics Data System (ADS)

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

Kou, Nannan

149

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

NASA Astrophysics Data System (ADS)

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.

Pumkaew, Watcharapol

150

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

Microsoft Academic Search

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

Thiam Leng Chew; Subhash Bhatia

2008-01-01

151

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

SciTech Connect

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 heatingthe same process used to render wood into charcoal, caramelize sugar, and dry roast coffee and beans. RTIs catalytic biomass pyrolysis differs from conventional flash pyrolysis in that its end product contains less oxygen, metals, and nitrogenall 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.

None

2010-01-01

152

Microalgae as a raw material for biofuels production  

Microsoft Academic Search

Biofuels demand is unquestionable in order to reduce gaseous emissions (fossil CO2, nitrogen and sulfur oxides) and their purported greenhouse, climatic changes and global warming effects, to face the frequent\\u000a oil supply crises, as a way to help non-fossil fuel producer countries to reduce energy dependence, contributing to security\\u000a of supply, promoting environmental sustainability and meeting the EU target of

Luisa Gouveia; Ana Cristina Oliveira

2009-01-01

153

Biofuel Production from Catalytic Cracking of Palm Oil  

Microsoft Academic Search

Palm oil, a renewable source, has been cracked at atmospheric pressure, a reaction temperature of 450C, and a weight hourly space velocity of 2.5 h to produce biofuel in a fixed-bed microreactor. The reaction was carried out over microporous HZSM-5 zeolite, mesoporous MCM-41, and composite micromesoporous zeolite as catalysts in order to study the influence of catalyst pore size and

OOI YEAN SANG

2003-01-01

154

Heterologous expression of plant cell wall degrading enzymes for effective production of cellulosic biofuels.  

PubMed

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

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

2012-01-01

155

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

PubMed

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

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

2014-11-01

156

An auto-inducible mechanism for ionic liquid resistance in microbial biofuel production.  

PubMed

Ionic liquids (ILs) are emerging as superior solvents for numerous industrial applications, including the pretreatment of biomass for the microbial production of biofuels. However, some of the most effective ILs used to solubilize cellulose inhibit microbial growth, decreasing efficiency in the overall process. Here we identify an IL-resistance mechanism consisting of two adjacent genes from Enterobacter lignolyticus, a rain forest soil bacterium that is tolerant to an imidazolium-based IL. These genes retain their full functionality when transferred to an Escherichia coli biofuel host, with IL resistance established by an inner membrane transporter, regulated by an IL-inducible repressor. Expression of the transporter is dynamically adjusted in direct response to IL, enabling growth and biofuel production at levels of IL that are toxic to native strains. This natural auto-regulatory system provides the basis for engineering IL-tolerant microbes, which should accelerate progress towards effective conversion of lignocellulosic biomass to fuels and renewable chemicals. PMID:24667370

Ruegg, Thomas L; Kim, Eun-Mi; Simmons, Blake A; Keasling, Jay D; Singer, Steven W; Soon Lee, Taek; Thelen, Michael P

2014-01-01

157

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

NASA Astrophysics Data System (ADS)

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

Li, Qi

158

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

PubMed Central

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

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

159

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

NASA Astrophysics Data System (ADS)

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

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

2010-12-01

160

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

161

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

NASA Astrophysics Data System (ADS)

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

Brown, Duncan

162

Biofuels from Lignocellulosic Biomass  

Microsoft Academic Search

\\u000a Biomass feedstock, which is mainly lignocellulose, has considerable potential to contribute to the future production of biofuels\\u000a and to the mitigation of carbon dioxide emissions. Several challenges exist in the production, harvesting, and conversion\\u000a aspects of lignocellulose, and these must be resolved in order to reach economic viability. A broad array of research projects\\u000a are underway to address the technical

Xiaorong Wu; James McLaren; Ron Madl; Donghai Wang

163

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

PubMed

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. PMID:23238340

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

2013-02-01

164

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

PubMed

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

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

165

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

SciTech Connect

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

McGill, Ralph [Sentech, Inc., Fuels, Engines, and Emissions Consulting, Knoxville, TN (United States)

2008-05-15

166

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

NASA Astrophysics Data System (ADS)

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.

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

2012-12-01

167

Symposium 16 Photoprotection, Photoinhibition and Dynamics 523 Improving the Photosynthetic Productivity and Light Utilization in Algal Biofuel Systems  

E-print Network

-term, and algae offer some of the best potential for a sustainable supply of renewable biofuels (Chisti, 2007 Productivity and Light Utilization in Algal Biofuel Systems: Metabolic and Physiological Characterization to as `IM') of the green alga Chlamydomonas reinhardtii with several unique attributes that has potential

Govindjee

168

A High-Resolution National Microalgae Biofuel Production and Resource Assessment  

NASA Astrophysics Data System (ADS)

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.

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

2012-12-01

169

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

SciTech Connect

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

Elcock, D.; Environmental Science Division

2010-06-01

170

Soil and crop response to harvesting corn residues for biofuel production  

Microsoft Academic Search

Corn (Zea mays L.) stover is considered one of the prime lignocellulosic feedstocks for biofuel production. While producing renewable energy from biomass is necessary, impacts of harvesting corn stover on soil organic carbon (SOC) sequestration, agricultural productivity, and environmental quality must be also carefully and objectively assessed. We conducted a 2 1\\/2year study of stover management in long-term (>8yr) no-tillage

Humberto Blanco-Canqui; R. Lal

2007-01-01

171

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

Microsoft Academic Search

A system dynamics model is developed to assess the availability and feasibility of non-traditional water sources from dairy wastewater, produced water from crude oil production and from coal-bed methane gas extraction for the production of algal-based biofuel. The conceptual framework is based on two locales within New Mexico, the San Juan basin in the northwest and the Permian basin in

A. C. Sun; M. D. Reno

2008-01-01

172

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

PubMed

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

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

2013-01-15

173

Algal biofuels.  

PubMed

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

Razeghifard, Reza

2013-11-01

174

Genetic resources for advanced biofuel production described with the Gene Ontology  

PubMed Central

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

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

2014-01-01

175

Biofuel production from catalytic cracking of woody oils  

Microsoft Academic Search

The catalytic cracking reactions of several kinds of woody oils have been studied. The products were analyzed by GCMS and FTIR and show the formation of olefins, paraffins and carboxylic acids. Several kinds of catalysts were compared. It was found that the fraction distribution of product was modified by using base catalysts such as CaO. The products from woody oils

Junming Xu; Jianchun Jiang; Jie Chen; Yunjuan Sun

2010-01-01

176

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

PubMed Central

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

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

2013-01-01

177

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

PubMed

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

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

2013-02-01

178

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

PubMed Central

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

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

179

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

PubMed

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, ?-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. PMID:24449684

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

2014-01-01

180

Biofuels Issues and Trends  

EIA Publications

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.

2012-01-01

181

Biofuels Production by Cell-Free Synthetic Enzymatic Technology  

Microsoft Academic Search

Biomass is the only renewable resource that can provide a sufficient fraction of both future transportation fuels and renewable materials at the same time. Synthetic biology is an emerging interdisciplinary area that combines science and engineering in order to design and build novel biological functions and systems. Different from in vivo synthetic biology, cell-free in vitro synthetic biology is a

Y. H. Percival Zhang; Xinhao Ye; Yiran Wang

2008-01-01

182

Biofuel production in Escherichia coli : the role of metabolic engineering and synthetic biology  

Microsoft Academic Search

The microbial production of biofuels is a promising avenue for the development of viable processes for the generation of fuels\\u000a from sustainable resources. In order to become cost and energy effective, these processes must utilize organisms that can\\u000a be optimized to efficiently produce candidate fuels from a variety of feedstocks. Escherichia coli has become a promising host organism for the

James M. Clomburg; Ramon Gonzalez

2010-01-01

183

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

Microsoft Academic Search

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 33C around 120gl -1 ethanol produced in 30h with a slight benefit for growth at 30C and for

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

2004-01-01

184

Microalgae for the production of bulk chemicals and biofuels  

Microsoft Academic Search

The feasibility of microalgae production for biodiesel was discussed. Although algae are not yet produced at large scale for bulk applications, there are opportunities to develop this process in a sustainable way. It remains unlikely, however, that the process will be developed for biodiesel as the only end product from microalgae. In order to develop a more sustainable and economically

Rene H Wijffels; Maria J Barbosa; Michel H M Eppink

2010-01-01

185

Forecasting energy security impacts of biofuels using regional climate models  

NASA Astrophysics Data System (ADS)

Production of biofuels in the U.S. is growing rapidly, with corn providing the dominant feedstock for current production and corn stover potentially providing a critical feedstock source for future cellulosic ethanol production. While production of domestic biofuels is thought to improve energy security, future changes in climate may impact crop yield variability and erode the energy security benefits of biofuels. Here we examine future yield variability for corn and soy using RegCM regional climate data from NARCAPP, historical agronomic data, and statistical models of yield variability. Our simulations of historical yield anomalies using monthly temperature and precipitation data from RegCM show robust relationships to observed yield anomalies. Simulations of future yield anomalies show increased yield variability relative to historical yield variability in the region of high corn production. Since variability in energy supply is a critical concern for energy security we suggest that the climate-induced yield variability on critical biofuels feedstocks be explored more widely.

Yang, X.; Campbell, E.; Snyder, M. A.; Sloan, L.; Kueppers, L. M.

2010-12-01

186

Development of New Technologies of Solid and Gaseous Biofuel Production  

NASA Astrophysics Data System (ADS)

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

Zaichenko, Victor

187

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

188

Economic Policy and Resource Implications of Biofuel Feedstock Production  

E-print Network

with huge taxpayer expenditures without due diligence to the consequences. The evaluation of the water quality impacts of converting pastureland to intensive biomass production for fuel in a southern Texas watershed suggest significant increases erosion...

Adusumilli, Naveen

2012-10-19

189

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

NASA Astrophysics Data System (ADS)

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

Vanloocke, A.; Bernacchi, C.

2008-12-01

190

Review of environmental, economic and policy aspects of biofuels  

Microsoft Academic Search

The world is witnessing a sudden growth in production of biofuels, especially those suited for replacing oil like ethanol and biodiesel. This paper synthesizes what the environmental, economic, and policy literature predicts about the possible effects of these types of biofuels. Another motivation is to identify gaps in understanding and recommend areas for future work. The analysis finds three key

David Zilberman; Deepak Rajagopal

2007-01-01

191

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

Microsoft Academic Search

\\u000a This issue of In Vitro Plant is dedicated to various aspects of biofuel research and development. The editors have sought the experts in this field\\u000a and solicited manuscripts for this special issue publication from various academic institutions, government (USDA, DOE), industry\\u000a (Mendel, Alellyx, Canavilas, Syngenta, Monsanto), and various countries (USA, China, Brazil, India, and Australia). This has\\u000a resulted in state-of-the-art

David Songstad; Prakash Lakshmanan; John Chen; William Gibbons; Stephen Hughes; R. Nelson

192

Historical perspective of biofuels: learning from the past to rediscover the future  

Microsoft Academic Search

This issue of in vitro plant is dedicated to various aspects of biofuel research and development. The editors have sought the experts in this field\\u000a and solicited manuscripts for this special issue publication from various academic institutions, government (USDA, DOE), industry\\u000a (Mendel, Alellyx, Canavilas, Syngenta, Monsanto), and various countries (USA, China, Brazil, India, and Australia). This has\\u000a resulted in state-of-the-art

D. D. Songstad; P. Lakshmanan; J. Chen; W. Gibbons; S. Hughes; R. Nelson

2009-01-01

193

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

NASA Astrophysics Data System (ADS)

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

Singh, Navneet R.

194

Biofuels from Corn Stover: Pyrolytic Production and Catalytic Upgrading Studies  

E-print Network

of phenolic compounds, with significant proportions of aromatic and aliphatic compounds. The gas product has energy content ranging from 10.1 to 21.7 MJ m-3, attributed to significant quantities of methane, hydrogen and carbon dioxide. Mass and energy...

Capunitan, Jewel Alviar

2013-01-15

195

Second Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production  

E-print Network

of fossil fuels is now widely accepted as unsustainable due to depleting resources and the accumulation of greenhouse gases in the environment that have already exceeded the "dangerously high" threshold of 450 ppm CO2-e. To achieve environmental and economic sustainability, fuel production processes are required

Kudela, Raphael M.

196

Production and Characterization of Biofuel from Coconut Oil  

Microsoft Academic Search

The biggest challenge for developing countries in relation to energy consumption is to develop and implement technologies that help reduce the emissions of gases and particulate matter (dust and smoke), which have both local and possible global environmental impacts. In order to be more environmentally conscious, we need to endeavor to use resources that preferentially create fewer pollutants as by-products.

A. S. Abdulkareem; J. O. Odigure; M. B. Kuranga

2010-01-01

197

Second Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production  

Microsoft Academic Search

The use of fossil fuels is now widely accepted as unsustainable due to depleting resources and the accumulation of greenhouse\\u000a gases in the environment that have already exceeded the dangerously high threshold of 450ppm CO2-e. To achieve environmental and economic sustainability, fuel production processes are required that are not only renewable,\\u000a but also capable of sequestering atmospheric CO2. Currently, nearly

Peer M. Schenk; Skye R. Thomas-Hall; Evan Stephens; Jan H. Mussgnug; Clemens Posten; Olaf Kruse; Ben Hankamer

2008-01-01

198

Techno-Economic Analysis of Biofuels Production Based on Gasification  

SciTech Connect

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.

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

2010-11-01

199

Bio-Fuel Production Assisted with High Temperature Steam Electrolysis  

SciTech Connect

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

Grant Hawkes; James O'Brien; Michael McKellar

2012-06-01

200

The benefits of biofuels  

SciTech Connect

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.

Hinman, N.D. [National Renewable Energy Lab., Golden, CO (United States)

1997-07-01

201

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

NASA Astrophysics Data System (ADS)

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

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

2008-12-01

202

Primary productivity and the prospects for biofuels in the United Kingdom  

NASA Astrophysics Data System (ADS)

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.

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

1983-09-01

203

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

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

204

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

PubMed

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. PMID:23928208

Markou, Giorgos; Nerantzis, Elias

2013-12-01

205

Catalytic Fast Pyrolysis for the Production of the Hydrocarbon Biofuels  

SciTech Connect

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

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

2013-01-01

206

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

PubMed

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

Cadoret, Jean-Paul; Bernard, Olivier

2008-01-01

207

Green chemistry, biofuels, and biorefinery.  

PubMed

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

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

2012-01-01

208

Perennial grass production for biofuels: Soil conversion considerations  

SciTech Connect

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.

McLaughlin, S.B. [Oak Ridge National Lab., TN (United States); Bransby, D.I. [Auburn Univ., AL (United States). Dept. of Agronomy and Soils; Parrish, D. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States). Dept. of Crop, Soil, and Environmental Sciences

1994-10-01

209

Microwave-assisted pyrolysis of microalgae for biofuel production.  

PubMed

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

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

2011-04-01

210

Production of biofuels, limonene and pectin from citrus wastes.  

PubMed

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. PMID:20149643

Pourbafrani, Mohammad; Forgcs, Gergely; Horvth, Ilona Srvri; Niklasson, Claes; Taherzadeh, Mohammad J

2010-06-01

211

Understanding and engineering enzymes for enhanced biofuel production.  

SciTech Connect

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.

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

2009-01-01

212

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

USGS Publications Warehouse

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 (4.770.6%) in sediment yield due to erosion and a slight decrease (1.23.2%) in water yield were estimated with the stover removal rate ranging between 40% and 100%, the nitrate nitrogen load declined about 610.1%. 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.

Wu, Y.; Liu, S.

2012-01-01

213

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

SciTech Connect

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.

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

2013-12-01

214

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

PubMed

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. PMID:24350430

Reijnders, L

2013-01-01

215

Impacts of Urbanization and Biofuels Production on The Price of Land in the Corn Belt: A Farm-Level Analysis  

Microsoft Academic Search

This study uses hedonic techniques to estimate the impact of urban influence, increased bio-fuels production, and environmental factors on land prices in the Corn Belt. We hypothesize that urban influence and ethanol production increase land prices on Corn Belt farms. Although not all states in the Corn Belt are entirely subject to urban influence and ethanol production impacts, some states

Richard Nehring; Kenneth Erickson; Vince Breneman; Alexandre Vialou; David Nulph

216

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

PubMed

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

Chew, Thiam Leng; Bhatia, Subhash

2008-11-01

217

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

218

Electricity production in biofuel cell using modified graphite electrode with Neutral Red  

Microsoft Academic Search

E. coliwas used as a biocatalyst to compare electricity production, substrate consumption and growth in biofuel cells. With the native electrode 1.44 mVcm-2-electrode and 1.41 Acm-2-electrode electricity were produced and 21mM acetate was consumed. With the modified electrode with Neutral Red, 3.12 mVcm-2-electrode and 3.1Acm-2-electrode electricity were produced and 39 mM acetate was consumed.

Doo Hyun Park; Si Kyoon Kim; In Ho Shin; Yoo Jung Jeong

2000-01-01

219

Spatial forecasting of switchgrass productivity under current and future climate change scenarios.  

PubMed

Evaluating the potential of alternative energy crops across large geographic regions, as well as over time, is a necessary component to determining if biofuel production is feasible and sustainable in the face of growing production demands and climatic change. Switchgrass (Panicum virgatum L.), a native perennial herbaceous grass, is a promising candidate for cellulosic feedstock production. In this study, current and future (from 2080 to 2090) productivity is estimated across the central and eastern United States using ALMANAC, a mechanistic model that simulates plant growth over time. The ALMANAC model was parameterized for representative ecotypes of switchgrass. Our results indicate substantial variation in switchgrass productivity both within regions and over time. States along the Gulf Coast, southern Atlantic Coast, and in the East North Central Midwest have the highest current biomass potential. However, these areas also contain critical wetland habitat necessary for the maintenance of biodiversity and agricultural lands necessary for food production. The southern United States is predicted to have the largest decrease in future biomass production. The Great Plains are expected to experience large increases in productivity by 2080-2090 due to climate change. In general, regions where future temperature and precipitation are predicted to increase are also where larger future biomass production is expected. In contrast, regions that show a future decrease in precipitation are associated with smaller future biomass production. Switchgrass appears to be a promising biofuel crop for the central and eastern United States, with local biomass predicted to be high (>10 Mg/ha) for approximately 50% of the area studied for each climate scenario. In order to minimize land conversion and loss of biodiversity, areas that currently have and maintain high productivity under climate change should be targeted for their long-term growth potential. PMID:23495637

Behrman, Kathrine D; Kiniry, James R; Winchell, Michael; Juenger, Thomas E; Keitt, Timothy H

2013-01-01

220

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

PubMed

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

Higgins, Brendan T; VanderGheynst, Jean S

2014-01-01

221

Fuel from Wastewater - Harnessing a Potential Energy Source in Canada through the Colocation of Algae Biofuel Production to Sources of Effluent, Heat and CO2  

Microsoft Academic Search

Sandia National Laboratories is collaborating with the National Research Council (NRC) Canada and the National Renewable Energy Laboratory (NREL) to develop a decision-support model that will evaluate the tradeoffs associated with high-latitude algae biofuel production co-located with wastewater, CO2, and waste heat. This project helps Canada meet its goal of diversifying fuel sources with algae-based biofuels. The biofuel production will

G. T. Klise; J. D. Roach; H. D. Passell; B. D. Moreland; S. J. O'Leary; P. T. Pienkos; J. Whalen

2010-01-01

222

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

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.

None

2012-02-15

223

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

SciTech Connect

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.

Sun, Amy Cha-Tien; Reno, Marissa Devan

2007-09-01

224

Nitrogen supply is an important driver of sustainable microalgae biofuel production.  

PubMed

Favorable growth characteristics continue to generate interest in using triacylglycerides (TAGs) produced from microalgae for biodiesel feedstocks. In this opinion article, we suggest that due to the energy consumption associated with the production of external nitrogen fertilizers, the manner in which nitrogen is supplied to microalgae biorefineries will be an important driver of energy yields, sustainability, and commercial success. Schemes including the reuse of urban wastewater represent improvements on the overall energy balance, but will not allow for significant production of biofuels unless the nitrogen from the non-TAG portions of microalgae is recycled. Approaches to recycling nitrogen require an improved understanding of the tradeoffs between the different potential uses of the non-TAG microalgal portion (i.e., energy production via anaerobic digestion or thermal catalytic processes), and the development of nitrogen separation technologies. PMID:23414785

Peccia, Jordan; Haznedaroglu, Berat; Gutierrez, James; Zimmerman, Julie B

2013-03-01

225

Biofuels and their By-Products: Global Economic and Environmental Implications  

Microsoft Academic Search

The biofuel industry has been rapidly growing around the world in recent years. Several papers have used general equilibrium models and addressed the economy-wide and environmental consequences of producing biofuels at a large scale. They mainly argue that since biofuels are mostly produced from agricultural sources, their effects are largely felt in agricultural markets with major land use and environmental

Farzad Thaeripour; Thomas W. Hertel; Wallace E. Tyner; Jayson F. Beckman; Dileep K. Birur

2008-01-01

226

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

PubMed Central

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

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

2013-01-01

227

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

NASA Astrophysics Data System (ADS)

There is considerable interest in biofuel production in the US Midwest; however, potential adverse impacts on water resources are a concern. This study explores relationships between hydrologic change and climate and land surface changes, based on long-term (1930s-2010) monitoring datasets of 45 stream gage stations. Sensitivity of streamflow and baseflow to climate was evaluated using an empirical climate elasticity approach and residuals were attributed to land surface changes. Results show significant increases in streamflow (2.10.3 mm/yr) in 24% of stations, increases in baseflow (0.70.3 mm/yr) in 60% of stations, and in baseflow index (0.20.1%/yr) in 44% of stations. Although climate variability and land surface changes contributed equally to streamflow changes, land surface changes contributed about three times more than climate variability to baseflow and seven times more to baseflow index. Watersheds (~50%) with no significant climate change but with significant flow change provide direct evidence that land surface changes in the Midwest, including crop types, tillage, tiling etc, produced significant impacts on hydrologic processes. Limiting analysis to these watersheds shows that ratios of land surface changes to climate variability was a factor of three for streamflow, 4.6 for baseflow, and 13.5 for baseflow index. These changes in flow have generally been accompanied by degradation of water quality. Because past changes in crop types have been dominated by perennial crops to annual (corn and soybeans) crops, reversal to more perennial grasses for second generation biofuels should reduce flow, particularly baseflow in the future, with consequent improvements in water quality.

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

2012-12-01

228

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

USGS Publications Warehouse

Increased phosphorus (P) loadings threaten the health of the worlds largest freshwater resource, the Laurentian Great Lakes (GL). To understand the linkages between land use and P delivery, we coupled two spatially explicit models, the landscape-scale SPARROW P fate and transport watershed model and the Land Transformation Model (LTM) land use change model, to predict future P export from nonpoint and point sources caused by changes in land use. According to LTM predictions over the period 20102040, the GL region of the U.S. may experience a doubling of urbanized areas and agricultural areas may increase by 10%, due to biofuel feedstock cultivation. These land use changes are predicted to increase P loadings from the U.S. side of the GL basin by 3.59.5%, depending on the Lake watershed and development scenario. The exception is Lake Ontario, where loading is predicted to decrease by 1.8% for one scenario, due to population losses in the drainage area. Overall, urban expansion is estimated to increase P loadings by 3.4%. Agricultural expansion associated with predicted biofuel feedstock cultivation is predicted to increase P loadings by an additional 2.4%. Watersheds that export P most ef?ciently and thus are the most vulnerable to increases in P sources tend to be found along southern Lake Ontario, southeastern Lake Erie, western Lake Michigan, and southwestern Lake Superior where watershed areas are concentrated along the coastline with shorter ?ow paths. In contrast, watersheds with high soil permeabilities, fractions of land underlain by tile drains, and long distances to the GL are less vulnerable.

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

2013-01-01

229

Water Resources Implications of Cellulosic Biofuel Production at a Regional Scale  

NASA Astrophysics Data System (ADS)

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

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

2011-12-01

230

Biofuel Feedstock Assessment For Selected Countries  

SciTech Connect

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

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

2008-02-01

231

Biofuel Feedstock Assessment for Selected Countries  

SciTech Connect

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

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

2008-02-18

232

Outlook for advanced biofuels  

Microsoft Academic Search

To assess which biofuels have the better potential for the short-term or the longer term (2030), and what developments are necessary to improve the performance of biofuels, the production of four promising biofuelsmethanol, ethanol, hydrogen, and synthetic dieselis systematically analysed. This present paper summarises, normalises and compares earlier reported work. First, the key technologies for the production of these fuels,

Carlo N. Hamelinck

2006-01-01

233

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

PubMed

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

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

2013-05-01

234

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

NASA Astrophysics Data System (ADS)

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

Takano, Maki; Hoshino, Kazuhiro

235

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

PubMed

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

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

2014-01-01

236

Fatty Acid-Derived Biofuels and Chemicals Production in Saccharomyces cerevisiae  

PubMed Central

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.

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

2014-01-01

237

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

NASA Astrophysics Data System (ADS)

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

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

2009-12-01

238

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

PubMed Central

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

2013-01-01

239

IPAD products and implications for the future  

NASA Technical Reports Server (NTRS)

The betterment of productivity through the improvement of product quality and the reduction of cost is addressed. Productivity improvement is sought through (1) reduction of required resources, (2) improved ask results through the management of such saved resources, (3) reduced downstream costs through manufacturing-oriented engineering, and (4) lowered risks in the making of product design decisions. The IPAD products are both hardware architecture and software distributed over a number of heterogeneous computers in this architecture. These IPAD products are described in terms of capability and engineering usefulness. The future implications of state-of-the-art IPAD hardware and software architectures are discussed in terms of their impact on the functions and on structures of organizations concerned with creating products.

Miller, R. E., Jr.

1980-01-01

240

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

NASA Astrophysics Data System (ADS)

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

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

2008-12-01

241

Life Cycle Analysis for Biofuel Pellet Production on Reclaimed Mountain Top Coal Mining Sites in Pike County, Kentucky  

Microsoft Academic Search

Mountaintop coal mining and valley filling drastically disturbs soils and removes essentially all soil organic carbon (SOC) from sites. Growing crops for biofuels on these marginal lands could be a practical way to sequester and offset carbon emissions from coal production and consumption. A life cycle model was developed to quantify the initial carbon density of the site and to

Alice Jones; Katie Young; James F. Fox; J. Campbell

2010-01-01

242

Livestock production: recent trends, future prospects  

PubMed Central

The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades. PMID:20713389

Thornton, Philip K.

2010-01-01

243

Livestock production: recent trends, future prospects.  

PubMed

The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades. PMID:20713389

Thornton, Philip K

2010-09-27

244

Excited Quark Production at Future p Colliders  

Microsoft Academic Search

Excited quark production at future p colliders is studied. Namely, p ! q?X with subsequent q? ! gq and q decay channels are considered. Signatures for discovery of the excited quark and corresponding standard model backgrounds are discussed in detail. Discovery limits for excited quark masses and achievable values of compositeness parameters fs, f and fare determined.

R. Ciftci

245

Biofuels Research at EPA  

EPA Science Inventory

The development of sustainable and clean biofuels is a national priority. To do so requires a life-cycle approach that includes consideration of feedstock production and logistics, and biofuel production, distribution, and end use. The US Environmental Protection Agency is suppor...

246

Extremophiles in biofuel synthesis  

Microsoft Academic Search

The current global energy situation has demonstrated an urgent need for the development of alternative fuel sources to the continually diminishing fossil fuel reserves. Much research to address this issue focuses on the development of financially viable technologies for the production of biofuels. The current market for biofuels, defined as fuel products obtained from organic substrates, is dominated by bioethanol,

Desire Barnard; Ana Casanueva; Marla Tuffin; Donald Cowan

2010-01-01

247

A GIS cost model to assess the availability of freshwater, seawater, and saline groundwater for algal biofuel production in the United States.  

PubMed

A key advantage of using microalgae for biofuel production is the ability of some algal strains to thrive in waters unsuitable for conventional crop irrigation such as saline groundwater or seawater. Nonetheless, the availability of sustainable water supplies will provide significant challenges for scale-up and development of algal biofuels. We conduct a partial techno-economic assessment based on the availability of freshwater, saline groundwater, and seawater for use in open pond algae cultivation systems. We explore water issues through GIS-based models of algae biofuel production, freshwater supply (constrained to less than 5% of mean annual flow per watershed) and costs, and cost-distance models for supplying seawater and saline groundwater. We estimate that, combined, these resources can support 9.46 10(7) m(3) yr(-1) (25 billion gallons yr(-1)) of renewable biodiesel production in the coterminous United States. Achievement of larger targets requires the utilization of less water efficient sites and relatively expensive saline waters. Despite the addition of freshwater supply constraints and saline water resources, the geographic conclusions are similar to our previous results. Freshwater availability and saline water delivery costs are most favorable for the coast of the Gulf of Mexico and Florida peninsula, where evaporation relative to precipitation is moderate. As a whole, the barren and scrub lands of the southwestern U.S. have limited freshwater supplies, and large net evaporation rates greatly increase the cost of saline alternatives due to the added makeup water required to maintain pond salinity. However, this and similar analyses are particularly sensitive to knowledge gaps in algae growth/lipid production performance and the proportion of freshwater resources available, key topics for future investigation. PMID:23495893

Venteris, Erik R; Skaggs, Richard L; Coleman, Andre M; Wigmosta, Mark S

2013-05-01

248

Thermophysical characterization of the seeds of invasive Chinese tallow tree: importance for biofuel production.  

PubMed

The limited supply of traditional fossil based fuels, and increased concern about their environmental impact has driven the interest in the utilization of biomass based energy sources, including those that are underutilized or otherwise nuisance species such as Chinese tallow trees (Triadica sebifera [L.]). This species is a prolific seeds producer, and this paper shows that they contain more than 50% lipids by mass that are suitable for conversion into biodiesel. We present here, for the first time, the seeds' thermophysical properties important for biofuel production. The seeds were characterized using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and ultimate analysis; their thermal conductivity, thermal diffusivity, and specific heat were determined. The characterization results were correlated to fatty acid composition and lipid content for whole seeds and individual layers, as well as to the protein, hemicellulose, cellulose, and lignin content. The TGA analysis indicated the presence, in addition to lipids, of hemicellulose, cellulose, lignin, and proteins, depending on the layer analyzed. Thermal conductivity and specific heat were, respectively 0.14 0.007 W/mK and 3843.5 171.16 J/kgK for wax, 0.20 0.002 W/mK and 2018.7 5.18 J/kgK for shells, 0.13 0.0 W/mK and 1237 3.15 J/kgK for internal kernel, and 0.13 0.000 W/mK and 2833.9 104.11 J/kgK for whole seeds. These properties and characterization method can be further used in engineering analysis used to determine the most optimum processing method for production of biofuels from this feedstock. PMID:23013244

Picou, Laura; Boldor, Doran

2012-10-16

249

Genome replication engineering assisted continuous evolution (GREACE) to improve microbial tolerance for biofuels production  

PubMed Central

Background Microbial production of biofuels requires robust cell growth and metabolism under tough conditions. Conventionally, such tolerance phenotypes were engineered through evolutionary engineering using the principle of Mutagenesis followed-by Selection. The iterative rounds of mutagenesis-selection and frequent manual interventions resulted in discontinuous and inefficient strain improvement processes. This work aimed to develop a more continuous and efficient evolutionary engineering method termed as Genome Replication Engineering Assisted Continuous Evolution (GREACE) using Mutagenesis coupled-with Selection as its core principle. Results The core design of GREACE is to introduce an in vivo continuous mutagenesis mechanism into microbial cells by introducing a group of genetically modified proofreading elements of the DNA polymerase complex to accelerate the evolution process under stressful conditions. The genotype stability and phenotype heritability can be stably maintained once the genetically modified proofreading element is removed, thus scarless mutants with desired phenotypes can be obtained. Kanamycin resistance of E. coli was rapidly improved to confirm the concept and feasibility of GREACE. Intrinsic mechanism analysis revealed that during the continuous evolution process, the accumulation of genetically modified proofreading elements with mutator activities endowed the host cells with enhanced adaptation advantages. We further showed that GREACE can also be applied to engineer n-butanol and acetate tolerances. In less than a month, an E. coli strain capable of growing under an n-butanol concentration of 1.25% was isolated. As for acetate tolerance, cell growth of the evolved E. coli strain increased by 8-fold under 0.1% of acetate. In addition, we discovered that adaptation to specific stresses prefers accumulation of genetically modified elements with specific mutator strengths. Conclusions We developed a novel GREACE method using Mutagenesis coupled-with Selection as core principle. Successful isolation of E. coli strains with improved n-butanol and acetate tolerances demonstrated the potential of GREACE as a promising method for strain improvement in biofuels production. PMID:24070173

2013-01-01

250

TWO-STAGE HETEROTROPHIC AND PHOTOTROPHIC CULTURE TECHNOLOGY FOR MICROALGAL BIOFUEL PRODUCTION .  

E-print Network

??Chair: Dr. Shulin Chen Microalgae are attractive feedstocks for producing renewable biofuels. In this dissertation, I developed a two-stage heterotrophic and phototrophic microalgae culture system (more)

[No author

2013-01-01

251

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

PubMed

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. PMID:23148719

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

2012-12-11

252

Switchgrass potential on reclaimed surface mines for biofuel production in West Virginia  

NASA Astrophysics Data System (ADS)

The high cost and environmental risks associated with non-renewable energy sources has caused an increased interest in, and development of renewable biofuels. Switchgrass (Panicum virgatum L.), a warm season perennial grass, has been investigated as a source of biofuel feedstock due to its high biomass production on marginal soils, its tolerance of harsh growing conditions, and its ability to provide habitat for wildlife and soil conservation cover. West Virginia contains vast expanses of reclaimed surface mine lands and could potentially benefit from the production of switchgrass as a biofuel feedstock. Furthermore, switchgrass production could satisfy Surface Mining Reclamation and Control Act of 1977 (SMCRA) requirements for reclamation bond release to mine operators. Three separate studies will be discussed in this thesis to determine if switchgrass grown on reclaimed surface mines can produce yields similar to yields from stands grown under normal agronomic conditions and what common surface mining reclamation practices may be most appropriate for growing switchgrass. The first study examined yield production of three commercially-available, upland switchgrass varieties grown on two reclaimed surface mines in production years two, three and four. The Hampshire Hill mine site, which was reclaimed in the late 1990s using top soil and treated municipal sludge, averaged 5,800 kg (ha-yr)-1 of switchgrass compared to 803 kg (ha-yr)-1 at the Hobet 21 site which was reclaimed with crushed, unweathered rock over compacted overburden. Site and variety interacted with Cave-in-Rock as the top performer at the more fertile Hampshire Hill site and Shawnee produced the highest yields at Hobet 21 (7,853 kg ha-1 and 1,086 kg ha-1 averaged across years, respectively). Switchgrass yields increased from 2009 to 2010, but declined from 2010 to 2011. Switchgrass yields from farmlands in this region averaged about 15000 kg (ha-yr)-1 in the research literature, so switchgrass grown on reclaimed lands appears to be about 50% lower. A second study to determine optimal nitrogen and mulch rates for switchgrass establishment began in June 2011 on two newly-reclaimed surface mines. Both sites were seeded at a rate of 11.2 kg pure live seed (PLS) ha-1 of Cave-in-Rock on replicated treatments of 0, 33.6 and 67.0 kg N ha-1, and high and low mulch rates of mulch applied as hydromulch. Switchgrass cover, frequency and yield improved with the addition of any amount of N fertilizer compared to no N application. There was no significant difference in yield associated with high and low levels of N. We also observed that yields were not affected by application of additional mulch. The final study compared a one- and two-harvest system in the fourth year of production at the Hampshire Hill and Hobet 21 sites. There was no increase in yield production utilizing a two-harvest system (2922 kg (ha-yr)-1, averaged across site) compared to a one-harvest system (3029 kg (ha-yr)-1). The data also showed that re-growth collected from July to October in the two-harvest system added negligible yield and that yield collected in July was comparable in one- and two-harvest systems.

Marra, Michael A.

253

Engineering plastid fatty acid biosynthesis to improve food quality and biofuel production in higher plants.  

PubMed

The ability to manipulate plant fatty acid biosynthesis by using new biotechnological approaches has allowed the production of transgenic plants with unusual fatty acid profile and increased oil content. This review focuses on the production of very long chain polyunsaturated fatty acids (VLCPUFAs) and the increase in oil content in plants using molecular biology tools. Evidences suggest that regular consumption of food rich in VLCPUFAs has multiple positive health benefits. Alternative sources of these nutritional fatty acids are found in cold-water fishes. However, fish stocks are in severe decline because of decades of overfishing, and also fish oils can be contaminated by the accumulation of toxic compounds. Recently, there is also an increase in oilseed use for the production of biofuels. This tendency is partly associated with the rapidly rising costs of petroleum, increased concern about the environmental impact of fossil oil and the attractive need to develop renewable sources of fuel. In contrast to this scenario, oil derived from crop plants is normally contaminant free and less environmentally aggressive. Genetic engineering of the plastid genome (plastome) offers a number of attractive advantages, including high-level foreign protein expression, marker-gene excision and transgene containment because of maternal inheritance of plastid genome in most crops. Here, we describe the possibility to improve fatty acid biosynthesis in plastids, production of new fatty acids and increase their content in plants by genetic engineering of plastid fatty acid biosynthesis via plastid transformation. PMID:21535359

Rogalski, Marcelo; Carrer, Helaine

2011-06-01

254

Addressing the challenges for sustainable production of algal biofuels: I. Algal strains and nutrient supply.  

PubMed

Microalgae hold promise for the production of sustainable replacement of fossil fuels due to their high growth rates, ability to grow on non-arable land and their high content, under the proper conditions, of high energy compounds that can be relatively easily chemically converted to fuels using existing technology. However, projected large-scale algal production raises a number of sustainability concerns concerning land use, net energy return, water use and nutrient supply. The state-of-the-art of algal production of biofuels is presented with emphasis on some possible avenues to provide answers to the sustainability questions that have been raised. Here, issues concerning algal strains and supply of nutrients for large-scale production are discussed. Since sustainability concerns necessitate the use of wastewaters for supply of bulk nutrients, emphasis is placed on the composition and suitability of different wastewater streams. At the same time, algal cultivation has proven useful in waste treatment processes, and thus this aspect is also treated in some detail. PMID:24350435

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

2013-01-01

255

Metabolic engineering of Saccharomyces cerevisiae for production of fatty acid-derived biofuels and chemicals.  

PubMed

As the serious effects of global climate change become apparent and access to fossil fuels becomes more limited, metabolic engineers and synthetic biologists are looking towards greener sources for transportation fuels. In recent years, microbial production of high-energy fuels by economically efficient bioprocesses has emerged as an attractive alternative to the traditional production of transportation fuels. Here, we engineered the budding yeast Saccharomyces cerevisiae to produce fatty acid-derived biofuels and chemicals from simple sugars. Specifically, we overexpressed all three fatty acid biosynthesis genes, namely acetyl-CoA carboxylase (ACC1), fatty acid synthase 1 (FAS1) and fatty acid synthase 2 (FAS2), in S. cerevisiae. When coupled to triacylglycerol (TAG) production, the engineered strain accumulated lipid to more than 17% of its dry cell weight, a four-fold improvement over the control strain. Understanding that TAG cannot be used directly as fuels, we also engineered S. cerevisiae to produce drop-in fuels and chemicals. Altering the terminal "converting enzyme" in the engineered strain led to the production of free fatty acids at a titer of approximately 400 mg/L, fatty alcohols at approximately 100mg/L and fatty acid ethyl esters (biodiesel) at approximately 5 mg/L directly from simple sugars. We envision that our approach will provide a scalable, controllable and economic route to this important class of chemicals. PMID:23899824

Runguphan, Weerawat; Keasling, Jay D

2014-01-01

256

%22Trojan Horse%22 strategy for deconstruction of biomass for biofuels production.  

SciTech Connect

Production of renewable biofuels to displace fossil fuels currently consumed in the transportation sector is a pressing multiagency national priority (DOE/USDA/EERE). Currently, nearly all fuel ethanol is produced from corn-derived starch. Dedicated 'energy crops' and agricultural waste are preferred long-term solutions for renewable, cheap, and globally available biofuels as they avoid some of the market pressures and secondary greenhouse gas emission challenges currently facing corn ethanol. These sources of lignocellulosic biomass are converted to fermentable sugars using a variety of chemical and thermochemical pretreatments, which disrupt cellulose and lignin cross-links, allowing exogenously added recombinant microbial enzymes to more efficiently hydrolyze the cellulose for 'deconstruction' into glucose. This process is plagued with inefficiencies, primarily due to the recalcitrance of cellulosic biomass, mass transfer issues during deconstruction, and low activity of recombinant deconstruction enzymes. Costs are also high due to the requirement for enzymes and reagents, and energy-intensive cumbersome pretreatment steps. One potential solution to these problems is found in synthetic biology-engineered plants that self-produce a suite of cellulase enzymes. Deconstruction can then be integrated into a one-step process, thereby increasing efficiency (cellulose-cellulase mass-transfer rates) and reducing costs. The unique aspects of our approach are the rationally engineered enzymes which become Trojan horses during pretreatment conditions. During this study we rationally engineered Cazy enzymes and then integrated them into plant cells by multiple transformation techniques. The regenerated plants were assayed for first expression of these messages and then for the resulting proteins. The plants were then subjected to consolidated bioprocessing and characterized in detail. Our results and possible implications of this work on developing dedicated energy crops and their advantage in a consolidated bioprocessing system.

Simmons, Blake Alexander; Sinclair, Michael B.; Yu, Eizadora; Timlin, Jerilyn Ann; Hadi, Masood Z.; Tran-Gyamfi, Mary

2011-02-01

257

Hydrothermal treatment of oleaginous yeast for the recovery of free fatty acids for use in advanced biofuel production.  

PubMed

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 5L bioreactors and the biomass slurry with 534% lipid content (dry weight basis) was treated at 280C for 1h with an initial pressure of 500psi in batch stainless steel reactors. The hydrolysis product was separated and each of the resulting streams was further characterized. The hexane soluble fraction contained fatty acids from the hydrolysis of yeast triacylglycerides, and was low in nitrogen and minerals and could be directly integrated as feedstock into pyrolysis processing to produce biofuels. The proposed hydrothermal treatment addresses some current technological bottlenecks associated with traditional methodologies such as dewatering, oil extraction and co-product utilization. It also enhances the feasibility of using microbial biomass for production of renewable fuels and chemicals. PMID:25034431

Espinosa-Gonzalez, Isabel; Parashar, Archana; Bressler, David C

2014-10-10

258

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

Microsoft Academic Search

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.

Nannan Kou

2011-01-01

259

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

Microsoft Academic Search

Events in world energy markets over the past several years have prompted many new technical developments as well as political support for alternative transportation fuels, especially those that are renewable. We have seen dramatic rises in the demand for and production of fuel ethanol from sugar cane and corn and biodiesel from vegetable oils. The quantities of these fuels being

McGill; Ralph

2008-01-01

260

Cooking Up More Uses for the Leftovers of Biofuel Production -N... http://www.nytimes.com/2007/08/08/business/08biodiesel.html?ei=... 1 of 3 8/8/07 10:49 AM  

E-print Network

Cooking Up More Uses for the Leftovers of Biofuel Production - N... http://www.nytimes.com/2007 Uses for the Leftovers of Biofuel Production By HILLARY ROSNER The baking tins and muffin cups lining to be true for biofuels," said Kenneth F. Reardon, a professor of chemical and biological engineering

Kimbrough, Steven Orla

261

The unintended energy impacts of increased nitrate contamination from biofuels production.  

PubMed

Increases in corn cultivation for biofuels production, due to the Energy Independence and Security Act of 2007, are likely to lead to increases in nitrate concentrations in both surface and groundwater resources in the United States. These increases might trigger the requirement for additional energy consumption for water treatment to remove the nitrates. While these increasing concentrations of nitrate might pose a human health concern, most water resources were found to be within current maximum contaminant level (MCL) limits of 10 mg L(-1) NO(3)-N. When water resources exceed this MCL, energy-intensive drinking water treatment is required to reduce nitrate levels below 10 mg L(-1). Based on prior estimates of water supplies currently exceeding the nitrate MCL, we calculate that advanced drinking water treatment might require an additional 2360 million kWh annually (for nitrate affected areas only)--a 2100% increase in energy requirements for water treatment in those same areas--to mitigate nitrate contamination and meet the MCL requirement. We predict that projected increases in nitrate contamination in water may impact the energy consumed in the water treatment sector, because of the convergence of several related trends: (1) increasing cornstarch-based ethanol production, (2) increasing nutrient loading in surface water and groundwater resources as a consequence of increased corn-based ethanol production, (3) additional drinking water sources that exceed the MCL for nitrate, and (4) potentially more stringent drinking water standards for nitrate. PMID:20082016

Twomey, Kelly M; Stillwell, Ashlynn S; Webber, Michael E

2010-01-01

262

Transgenics are imperative for biofuel crops  

Microsoft Academic Search

Petroleum dependency is a challenge that can potentially be partly offset by agricultural production of biofuels, while decreasing net, non-renewable carbon dioxide output. Plants have not been domesticated for modern biofuel production, and the quickest, most efficient, and often, the only way to convert plants to biofuel feedstocks is biotechnologically. First generation biofuel feedstock sources: sugarcane and cereal grains to

Jonathan Gressel

2008-01-01

263

Stimulating learning-by-doing in advanced biofuels: effectiveness of alternative policies  

NASA Astrophysics Data System (ADS)

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.

Chen, Xiaoguang; Khanna, Madhu; Yeh, Sonia

2012-12-01

264

The significance of nitrous oxide emission due to cropping of grain for biofuel production: a Swedish perspective  

NASA Astrophysics Data System (ADS)

The current regulations governing production of biofuels in the European Union require that they have to mitigate climate change, by producing >35% less greenhouse gases (GHG) than fossil fuels. There is a risk that this may not be achievable, since land use for crop production inevitably emits the potent GHG nitrous oxide (N2O), due to nitrogen fertilisation and cycling in the environment. We analyse first-generation biofuel production on agricultural land and conclude that efficient agricultural crop production resulting in a good harvest and low N2O emission can fulfil the EU standard, and is possible under certain conditions for the Swedish agricultural and bioethanol production systems. However, in years having low crop yields, and where cropping is on organic soils, total GHG emissions per unit of fuel produced can be even higher than those released by burning of fossil fuels. In general, the N2O emission size in Sweden and elsewhere in northern Europe is such that there is a >50% chance that the 35% saving requirement will not be met. Thus ecosystem N2O emissions have to be convincingly assessed. Here we compare Swedish emission data with values estimated by means of statistical models and by a global, top-down, approach; the measurements and the predictions often show higher values that would fail to meet the EU standard and thus prevent biofuel production development.

Kasimir Klemedtsson, .; Smith, K. A.

2011-12-01

265

Algal production in wastewater treatment high rate algal ponds for potential biofuel use.  

PubMed

Wastewater treatment High Rate Algal Ponds with CO2 addition could provide cost-effective and efficient tertiary-level wastewater treatment with the co-benefit of algal biomass production for biofuel use. Wastewater grown algal biomass can have a lipid content of 10-30% of dry weight, which could be used to make biodiesel. This research investigated algal biomass and total lipid production by two pilot-scale wastewater treatment HRAP(S) (4-day HRT) with and without CO2 addition under New Zealand mid summer (Nov-Jan) conditions. The influence of CO2 addition on wastewater treatment performance was also determined. CO2 was added to one of the HRAPs (the HRAP(E)) by maintaining the maximum pH of the pond below 8. Measurements of HRAP influent and effluent water qualities, total lipid content and algal biomass production were made twice a week over the experimental period. Both HRAP(S) achieved high levels of organic compound and nutrient removal, with >85% SBOD5, >92 NH4(+)-N and >70% DRP removal. Algal/bacterial biomass production in the HRAP(E) (15.2 g/m2/d) was improved by CO2 addition by approximately 30% compared with that of the control HRAP(W) (10.6 g/m2/d). Total lipid content of the biomass grown on both HRAP(S) was slightly reduced (from 25% to 20%) with CO2 addition and the maximum total lipid content of approximately 40% was observed in the HRAP(W) when low NH4(+)-N concentration (<0.5 mg/L) and high maximum pH (>10.0) occurred. Total lipid content of the biomass increased by approximately 15% under nitrogen limiting conditions, however, overall algal/bacterial biomass production was reduced by half during the period of nitrogen limitation. More research is required to maintain algal production under near nitrogen-limiting conditions. PMID:21977667

Park, J B K; Craggs, R J

2011-01-01

266

N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels  

NASA Astrophysics Data System (ADS)

The relationship, on a global basis, between the amount of N fixed by chemical, biological or atmospheric processes entering the terrestrial biosphere, and the total emission of nitrous oxide (N2O), has been re-examined, using known global atmospheric removal rates and concentration growth of N2O as a proxy for overall emissions. The relationship, in both the pre-industrial period and in recent times, after taking into account the large-scale changes in synthetic N fertiliser production and deforestation, is consistent, showing an overall conversion factor of 3-5%. This factor is covered only in part by the ~1% of "direct" emissions from agricultural crop lands estimated by IPCC (2006), or the "indirect" emissions cited therein. This means that the extra N2O entering the atmosphere as a result of using N to produce crops for biofuels will also be correspondingly greater than that estimated just on the basis of IPCC (2006). When the extra N2O emission from biofuel production is calculated in "CO2-equivalent" global warming terms, and compared with the quasi-cooling effect of "saving" emissions of fossil fuel derived CO2, the outcome is that the production of commonly used biofuels, such as biodiesel from rapeseed and bioethanol from corn (maize), can contribute as much or more to global warming by N2O emissions than cooling by fossil fuel savings. Crops with less N demand, such as grasses and woody coppice species have more favourable climate impacts. This analysis only considers the conversion of biomass to biofuel. It does not take into account the use of fossil fuel on the farms and for fertilizer and pesticide production, but it also neglects the production of useful co-products. Both factors partially compensate each other. This needs to be analyzed in a full life cycle assessment.

Crutzen, P. J.; Mosier, A. R.; Smith, K. A.; Winiwarter, W.

2007-08-01

267

Unintended Environmental Consequences of a Global Biofuels Program  

NASA Astrophysics Data System (ADS)

Biofuels are being promoted as an important part of the global energy mix to meet the climate change challenge. The environmental costs of biofuels produced with current technologies at small scales have been studied, but little research has been done on the consequences of an aggressive global biofuels program with advanced technologies using cellulosic feedstocks. Using a simulation modeling approach, we explore two scenarios for cellulosic biofuels production and find that with either one, biofuels could make a substantial contribution to meeting global-scale energy needs in the future, but with significant unintended environmental consequences. If forests are cleared to grow cellulosic biofuels crops, we estimate that about 105 Pg C would be released to the atmosphere as carbon dioxide and would cancel any greenhouse-gas savings from the substitution of biofuels for fossil fuels during the first half of the 21st century. Alternatively, if most cellulosic biofuels are grown on previously cleared land or land cleared of low-stature natural vegetation, we estimate that up to 30 Pg C would still be released to the atmosphere before a net greenhouse gas benefit from a global biofuels program is realized about the middle of the 21st century. With either alternative, we expect most of the world's cellulosic biofuels crops (14 to 15 million km2) to be grown on the relatively inexpensive but productive lands of the sub-tropics and tropics, with negative impacts on the biodiversity of these regions. Cellulosic biofuels may yet serve as a crucial wedge in the solution to the climate change problem, but must be deployed with caution so as not to jeopardize biodiversity, compromise ecosystems services, or undermine climate policy.

Kicklighter, D. W.; Gurgel, A. C.; Melillo, J. M.; Reilly, J.; Cronin, T. W.; Felzer, B. S.; Paltsev, S.; Schlosser, C. A.; Sokolov, A. P.

2008-12-01

268

Danielle Goldtooth Paper #6 -Biofuels  

E-print Network

Jon Kroc Danielle Goldtooth IS 195A Paper #6 - Biofuels Green Dreams In the modern era science has. Biofuels are increasingly becoming viable alternatives to gasoline, diesel, and other non-renewable fuels." There are still many issues that must be dealt with before the production of biofuels is energy-efficient enough

Lega, Joceline

269

Biofuel cells and their development.  

PubMed

This review considers the literature published since 1994 on microbial and enzymatic biofuel cells. Types of biofuel cell are classified according to the nature of the electrode reaction and the nature of the biochemical reactions. The performance of fuel cells is critically reviewed and a variety of possible applications is considered. The current direction of development of biofuel cells is carefully analysed. While considerable chemical development of enzyme electrodes has occurred, relatively little progress has been made towards the engineering development biofuel cells. The limit of performance of biofuel cells is highlighted and suggestions for future research directions are provided. PMID:16569499

Bullen, R A; Arnot, T C; Lakeman, J B; Walsh, F C

2006-05-15

270

Fuel for the Future: Development of New Fuels, e.g. Biofuels  

NASA Astrophysics Data System (ADS)

Whether we like it or not, climate change is to some extent affiliated with the emission of green house gasses, and specifically CO2 emissions, which are rising due to the global increased use of fossil fuels. As a result, political enthusiasm is high when it comes to implementing new initiatives aimed at better protection of the global environment. However, environmental concerns are just one aspect of the issues associated with the use of fossil fuels, since fossil fuels are a natural reserve and, therefore, a limited resource. Prognoses vary, but within the next decades the fossil fuel reserves will be exhausted leading to reduced oil production, rising oil prices, and the risk of international bellicose conflicts caused by adverse national interests. Additionally, fossil fuel as a natural reserve is unevenly distributed, meaning that a few countries possess the main energy reserve of the entire world. The incorporation of alternatives to fossil fuel into the existing fuel infrastructure is currently under intense development in the Western world, both to cut the oil dependency and to counter the depletion of oil reserves. This political enthusiasm to decrease the use of fossil fuel is emphasised by the fact that according to the International Energy Agency (IEA) more than 80% of the global primary energy consumption in 2007 accounts from fossil fuels and half of this is oil. More than 60% of the oil is used in the transport sector.

Srensen, Gitte; Srensen, Ketil Bernt; Hansen, Hans Ove; Nygaard, Sune D.

271

Neochloris oleabundans UTEX #1185: a suitable renewable lipid source for biofuel production.  

PubMed

Energy crises, global warming, and climatic changes call for technological and commercial advances in manufacturing high-quality transportation fuels from unconventional feedstocks. Microalgae is one of the most promising sources of biofuels due to the high yields attained per unit area and because it does not displace food crops. Neochloris oleabundans (Neo) microalga is an important promising microbial source of single-cell oil (SCO). Different experimental growth and lipid production conditions were evaluated and compared by using optical density (540 nm), dry-weight determination, and flow cytometry (FC). Best Neo average biomass productivity was obtained at 30 degrees C under conditions of nitrogen-sufficiency and CO(2) supplementation (N+/30 degrees C/CO(2)), with an average doubling time of 1.4 days. The second and third highest productivities occurred with N-sufficient cultures without CO(2) supplementation at 26 degrees C (N+/26 degrees C) and at 30 degrees C (N+/30 degrees C), with doubling times of 1.7 and 2.2 days, respectively. Microbial lipid production was monitored by flow cytometry using Nile red (NR), a lipophilic fluorochrome that possesses several advantageous characteristics for in situ screening near real time (at line). Results showed maximum lipid content (56%) after 6 days of nitrogen depletion under nitrogen starvation without CO(2) supplementation (N-/30 degrees C), followed by N-/30 degrees C/CO(2) and N-/26 degrees C conditions with 52% lipid content, after 5 and 6 days of N starvation, respectively. The adequate fatty acid profile and iodine value of Neo lipids reinforced this microalga as a good source of SCO, in particular for use as biodiesel. PMID:19377896

Gouveia, Lusa; Marques, Ana Evangelista; da Silva, Teresa Lopes; Reis, Alberto

2009-06-01

272

Biofuels and sustainability.  

PubMed

Interest in liquid biofuels production and use has increased worldwide as part of government policies to address the growing scarcity and riskiness of petroleum use, and, at least in theory, to help mitigate adverse global climate change. The existing biofuels markets are dominated by U.S. ethanol production based on cornstarch, Brazilian ethanol production based on sugarcane, and European biodiesel production based on rapeseed oil. Other promising efforts have included programs to shift toward the production and use of biofuels based on residues and waste materials from the agricultural and forestry sectors, and perennial grasses, such as switchgrass and miscanthus--so-called cellulosic ethanol. This article reviews these efforts and the recent literature in the context of ecological economics and sustainability science. Several common dimensions for sustainable biofuels are discussed: scale (resource assessment, land availability, and land use practices); efficiency (economic and energy); equity (geographic distribution of resources and the "food versus fuel" debate); socio-economic issues; and environmental effects and emissions. Recent proposals have been made for the development of sustainable biofuels criteria, culminating in standards released in Sweden in 2008 and a draft report from the international Roundtable on Sustainable Biofuels. These criteria hold promise for accelerating a shift away from unsustainable biofuels based on grain, such as corn, and toward possible sustainable feedstock and production practices that may be able to meet a variety of social, economic, and environmental sustainability criteria. PMID:20146765

Solomon, Barry D

2010-01-01

273

Metabolic Engineering of Clostridium thermocellum for Biofuel Production (2013 DOE JGI Genomics of Energy and Environment 8th Annual User Meeting)  

SciTech Connect

Adam Guss of Oak Ridge National Lab on "Metabolic engineering of Clostridium thermocellum for biofuel production" at the 8th Annual Genomics of Energy & Environment Meeting on March 28, 2013 in Walnut Creek, Calif.

Guess, Adam [ORNL

2013-03-01

274

The Impact of Biofuel and Greenhouse Gas Policies on Land Management, Agricultural Production, and Environmental Quality  

E-print Network

This dissertation explores the combined effects of biofuel mandates and terrestrial greenhouse gas GHG mitigation incentives on land use, management intensity, commodity markets, welfare, and the full costs of GHG abatement through conceptual...

Baker, Justin Scott

2012-10-19

275

A life cycle assessment of advanced biofuel production from a hectare of corn  

Microsoft Academic Search

Conventional agricultural life cycle assessments (LCAs) measure greenhouse gas (GHG) emissions for biofuel pathways as the amount of carbon dioxide equivalent emitted per unit of energy provided by the pathway (i.e. gCO2e\\/MJ). This measure of GHG emissions, as computed by the Environmental Protection Agency (EPA) is then used to determine the extent to which the corresponding biofuel pathway complies with

Nathan Kauffman; Dermot Hayes; Robert Brown

2011-01-01

276

Evaluation of target efficiencies for solid-liquid separation steps in biofuels production.  

PubMed

Development of liquid biofuels has entered a new phase of large scale pilot demonstration. A number of plants that are in operation or under construction face the task of addressing the engineering challenges of creating a viable plant design, scaling up and optimizing various unit operations. It is well-known that separation technologies account for 50-70% of both capital and operating cost. Additionally, reduction of environmental impact creates technological challenges that increase project cost without adding to the bottom line. Different technologies vary in terms of selection of unit operations; however, solid-liquid separations are likely to be a major contributor to the overall project cost. Despite the differences in pretreatment approaches, similar challenges arise for solid-liquid separation unit operations. A typical process for ethanol production from biomass includes several solid-liquid separation steps, depending on which particular stream is targeted for downstream processing. The nature of biomass-derived materials makes it either difficult or uneconomical to accomplish complete separation in a single step. Therefore, setting realistic efficiency targets for solid-liquid separations is an important task that influences overall process recovery and economics. Experimental data will be presented showing typical characteristics for pretreated cane bagasse at various stages of processing into cellulosic ethanol. Results of generic material balance calculations will be presented to illustrate the influence of separation target efficiencies on overall process recoveries and characteristics of waste streams. PMID:20607445

Kochergin, Vadim; Miller, Keith

2011-01-01

277

Developing Research Capabilities in Energy Biosciences: Design principles of photosynthetic biofuel production.  

SciTech Connect

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.

Donald D. Brown; David Savage

2012-06-30

278

Algae harvesting for biofuel production: influences of UV irradiation and polyethylenimine (PEI) coating on bacterial biocoagulation.  

PubMed

There is a pressing need to develop efficient and sustainable separation technologies to harvest algae for biofuel production. In this work, two bacterial species (Escherichia coli and Rhodococus sp.) were used as biocoagulants to harvest Chlorella zofingiensis and Scenedesmus dimorphus. The influences of UV irradiation and polyethylenimine (PEI)-coating on the algal harvesting efficiency were investigated. Results showed that the UV irradiation could slightly enhance bacteria-algae biocoagulation and algal harvesting efficiency. In contrast, the PEI-coated E. coli cells noticeably increased the harvesting efficiencies from 23% to 83% for S. dimorphus when compared to uncoated E. coli cells. Based on the soft-particle Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, an energy barrier existed between uncoated E. coli cells and algal cells, whereas the PEI coating on E. coli cells eliminated the energy barrier, thereby the biocoagulation was significantly improved. Overall, this work presented groundwork toward the potential use of bacterial biomass for algal harvesting from water. PMID:24926598

Agbakpe, Michael; Ge, Shijian; Zhang, Wen; Zhang, Xuezhi; Kobylarz, Patricia

2014-08-01

279

Production of biofuel from waste cooking palm oil using nanocrystalline zeolite as catalyst: process optimization studies.  

PubMed

The catalytic cracking of waste cooking palm oil to biofuel was studied over different types of nano-crystalline zeolite catalysts in a fixed bed reactor. The effect of reaction temperature (400-500 C), catalyst-to-oil ratio (6-14) and catalyst pore size of different nanocrystalline zeolites (0.54-0.80 nm) were studied over the conversion of waste cooking palm oil, yields of Organic Liquid Product (OLP) and gasoline fraction in the OLP following central composite design (CCD). The response surface methodology was used to determine the optimum value of the operating variables for maximum conversion as well as maximum yield of OLP and gasoline fraction, respectively. The optimum reaction temperature of 458 C with oil/catalyst ratio=6 over the nanocrystalline zeolite Y with pore size of 0.67 nm gave 86.4 wt% oil conversion, 46.5 wt% OLP yield and 33.5 wt% gasoline fraction yield, respectively. The experimental results were in agreement with the simulated values within an experimental error of less than 5%. PMID:21924606

Taufiqurrahmi, Niken; Mohamed, Abdul Rahman; Bhatia, Subhash

2011-11-01

280

Biofuels from Microalgae  

Microsoft Academic Search

Microalgae are a diverse group of prokaryotic and eukaryotic photosynthetic microorganisms that grow rapidly due to their simple structure. They can potentially be employed for the production of biofuels in an economically effective and environmentally sustainable manner. Microalgae have been investigated for the production of a number of different biofuels including biodiesel, bio-oil, bio-syngas, and bio-hydrogen. The production of these

Yanqun Li; Mark Horsman; Nan Wu; Christopher Q. Lan; Nathalie Dubois-Calero

2008-01-01

281

Agrigenomics for microalgal biofuel production: an overview of various bioinformatics resources and recent studies to link OMICS to bioenergy and bioeconomy.  

PubMed

Microalgal biofuels offer great promise in contributing to the growing global demand for alternative sources of renewable energy. However, to make algae-based fuels cost competitive with petroleum, lipid production capabilities of microalgae need to improve substantially. Recent progress in algal genomics, in conjunction with other "omic" approaches, has accelerated the ability to identify metabolic pathways and genes that are potential targets in the development of genetically engineered microalgal strains with optimum lipid content. In this review, we summarize the current bioeconomic status of global biofuel feedstocks with particular reference to the role of "omics" in optimizing sustainable biofuel production. We also provide an overview of the various databases and bioinformatics resources available to gain a more complete understanding of lipid metabolism across algal species, along with the recent contributions of "omic" approaches in the metabolic pathway studies for microalgal biofuel production. PMID:24044362

Misra, Namrata; Panda, Prasanna Kumar; Parida, Bikram Kumar

2013-11-01

282

Agrigenomics for Microalgal Biofuel Production: An Overview of Various Bioinformatics Resources and Recent Studies to Link OMICS to Bioenergy and Bioeconomy  

PubMed Central

Abstract Microalgal biofuels offer great promise in contributing to the growing global demand for alternative sources of renewable energy. However, to make algae-based fuels cost competitive with petroleum, lipid production capabilities of microalgae need to improve substantially. Recent progress in algal genomics, in conjunction with other omic approaches, has accelerated the ability to identify metabolic pathways and genes that are potential targets in the development of genetically engineered microalgal strains with optimum lipid content. In this review, we summarize the current bioeconomic status of global biofuel feedstocks with particular reference to the role of omics in optimizing sustainable biofuel production. We also provide an overview of the various databases and bioinformatics resources available to gain a more complete understanding of lipid metabolism across algal species, along with the recent contributions of omic approaches in the metabolic pathway studies for microalgal biofuel production. PMID:24044362

Misra, Namrata; Parida, Bikram Kumar

2013-01-01

283

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes  

PubMed Central

Increased demand for corn grain as an ethanol feedstock is altering U.S. agricultural landscapes and the ecosystem services they provide. From 2006 to 2007, corn acreage increased 19% nationally, resulting in reduced crop diversity in many areas. Biological control of insects is an ecosystem service that is strongly influenced by local landscape structure. Here, we estimate the value of natural biological control of the soybean aphid, a major pest in agricultural landscapes, and the economic impacts of reduced biocontrol caused by increased corn production in 4 U.S. states (Iowa, Michigan, Minnesota, and Wisconsin). For producers who use an integrated pest management strategy including insecticides as needed, natural suppression of soybean aphid in soybean is worth an average of $33 ha?1. At 20072008 prices these services are worth at least $239 million y?1 in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversity, altering the supply of aphid natural enemies to soybean fields and reducing biocontrol services by 24%. This loss of biocontrol services cost soybean producers in these states an estimated $58 million y?1 in reduced yield and increased pesticide use. For producers who rely solely on biological control, the value of lost services is much greater. These findings from a single pest in 1 crop suggest that the value of biocontrol services to the U.S. economy may be underestimated. Furthermore, we suggest that development of cellulosic ethanol production processes that use a variety of feedstocks could foster increased diversity in agricultural landscapes and enhance arthropod-mediated ecosystem services. PMID:19075234

Landis, Douglas A.; Gardiner, Mary M.; van der Werf, Wopke; Swinton, Scott M.

2008-01-01

284

Ecopolis: Biofuels  

NSDL National Science Digital Library

This 3-minute video explains how algae, a biofuel, is being developed as an energy source. It also discusses disadvantages of current biofuels and how algae will overcome these disadvantages. The site also provides links to videos about related topics.

Channel, Science

285

Spatial Optimization of Cropping Pattern in an Agricultural Watershed for Food and Biofuel Production with Minimum Downstream Pollution  

NASA Astrophysics Data System (ADS)

Biofuel is considered to be a viable alternative to meet the increasing fuel demand, and therefore many countries are promoting agricultural activities that help increase production of raw material for biofuel production. Mostly, the biofuel is produced from grain based crops such as Corn, and it apparently create a shortage in food grains. Consequently, there have been regulations to limit the ethanol production from grains, and to use cellulosic crops as raw material for biofuel production. However, cultivation of such cellulosic crops may have different effects on water quality in the watershed. Corn stover, one of the potential cellulosic materials, when removed from the agricultural field for biofuel production, causes a decrease in the organic nutrients in the field. This results in increased use of pesticides and fertilizers which in turn affect the downstream water quality due to leaching of the chemicals. On the contrary, planting less fertilizer-intensive cellulosic crops, like Switch Grass and Miscanthus, is expected to reduce the pollutant loadings from the watershed. Therefore, an ecologically viable land use scenario would be a mixed cropping of grain crops and cellulosic crops, that meet the demand for food and biofuel without compromising on the downstream water quality. Such cropping pattern can be arrived through a simulation-optimization framework. Mathematical models can be employed to evaluate various management scenarios related to crop production and to assess its impact on water quality. Soil and Water Assessment Tool (SWAT) model is one of the most widely used models in this context. SWAT can simulate the water and nutrient cycles, and also quantify the long-term impacts of land management practices, in a watershed. This model can therefore help take decisions regarding the type of cropping and management practices to be adopted in the watershed such that the water quality in the rivers is maintained at acceptable level. In this study, it is proposed to link SWAT model with an optimization algorithm, whose objective is to identify the optimal cropping pattern that results in maximum biomass production for biofuel generation as well as a minimum guaranteed amount of grain production. The optimal allocation ensures that the downstream water quality in the river is within a desirable limit. The study employed probabilistic information in order to address the uncertainty in model simulations. The residual variance of the model is used to transform the deterministic simulations in to probabilistic information. The proposed framework is illustrated using data pertaining to an agricultural watershed in the USA. The preliminary results of the study are encouraging and suggest that an appropriate combination of Corn, Soyabean, Miscanthus, Switch Grass and Pasture land can be arrived at through the developed framework. The placement of Miscanthus and Switch Grass in the watershed help improve the downstream water quality, while Corn and Soyabean makes it deteriorated. The spatial allocation of these crops therefore certainly plays a major role in the downstream water quality.

Pv, F.; Sudheer, K.; Chaubey, I.; RAJ, C.; Her, Y.

2013-05-01

286

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

PubMed

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. PMID:23650260

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

2013-06-01

287

Biofuels sources, biofuel policy, biofuel economy and global biofuel projections  

Microsoft Academic Search

The term biofuel is referred to liquid, gas and solid fuels predominantly produced from biomass. Biofuels include energy security reasons, environmental concerns, foreign exchange savings, and socioeconomic issues related to the rural sector. Biofuels include bioethanol, biomethanol, vegetable oils, biodiesel, biogas, bio-synthetic gas (bio-syngas), bio-oil, bio-char, Fischer-Tropsch liquids, and biohydrogen. Most traditional biofuels, such as ethanol from corn, wheat, or

Ayhan Demirbas

2008-01-01

288

Biofuel Ethanol Transport Risk  

EPA Science Inventory

Ethanol production has increased rapidly over the last 10 years and many communities lack awareness of the increased and growing extent of biofuel transportation through their jurisdictions. These communities and their emergency responders may not have the information and resour...

289

Biofuels: balancing risks and rewards  

PubMed Central

This paper describes a framework that can be used to evaluate the environmental risks and benefits associated with biofuel production. It uses the example of biodiesel produced from Argentinean soy to show how such a framework can be used to conceptualize trade-offs between different environmental, social and economic impacts of biofuel production. Results showing the greenhouse-gas savings and overall life-cycle impact of different soy-biodiesel production methods are presented. These impacts and the significance of uncertainty in overall assessments of key parameters, such as greenhouse-gas savings, are discussed. It is shown that, even where sufficient knowledge exists to be able to quantify these impacts, the sustainability of supply of a particular biofuel is inextricably linked to values and ethical judgements. However, tailoring certification efforts to the issues that are most likely to make a significant difference to the overall sustainability could improve the effectiveness of certification efforts. The potential for a framework to guide and focus certification efforts is discussed and future research and policy priorities suggested. PMID:24427513

Thornley, Patricia; Gilbert, Paul

2013-01-01

290

Different Effects of Corn Ethanol and Switchgrass-Based Biofuels on Soil Erosion and Nutrients Loads in the Iowa River Basin  

Microsoft Academic Search

Biofuels have become important alternative energy resources and their use is likely to expand in the foreseeable future. The expansion of corn-based ethanol production has resulted in a tightening of the global corn supply-and-demand balance. Perennial grasses such as switchgrass (Panicum virgatum) are also being considered as candidates for biofuel feedstocks. Expansion of biofuel production will generate diverse impacts on

Y. Wu; S. Liu

2010-01-01

291

Energy crops for biofuel feedstocks: facts and recent patents on genetic manipulation to improve biofuel crops.  

PubMed

Burning fossil-fuels to meet the global energy requirements by human being has intensified the concerns of increasing concentrations of greenhouse gases. Therefore, serious efforts are required to develop nonfossil-based renewable energy sources. Plants are more efficient in utilizing solar energy to convert it into biomass which can be used as feedstocks for biofuel production. Hence with the increasing demands of energy and the needs of cost-effective, sustainable production of fuels, it has become necessary to switch over to plant biomass as a renewable source of energy. Biofuels derived from more sustainable biological materials such as lignocellulosic plant residues, considered as second generation biofuels, are more dependable. However, there are technical challenges such as pretreatment and hydrolysis of lignocellulosic biomass to convert it into fermentable sugars. Plant genetic engineering has already proven its potential in modifying cell wall composition of plants for enhancing the efficiency of biofuel production. Interest and potential in the area are very much evident from the growing number of patents in the recent years on the subject. In this review, recent trends in genetic engineering of energy crops for biofuel production have been introduced, and strategies for the future developments have been discussed. PMID:24456235

Kumar, Suresh

2013-12-01

292

Rapid Manufacturing: The Future of Production Systems  

NSDL National Science Digital Library

Rapid Prototyping is a technology that converts three-dimensional computer models into physical parts typically by building layers upon layer of material. This technology has been serving designers for almost 20 years in support of demonstrating, testing, and confirming their designs early and frequently in the product development process. Increasing interest of designers in Rapid Prototyping (RP) in the last decade has led to development of new technologies and advancements in RP materials. Building a functional part or assembly directly from its CAD (Computer Aided Design) model gave manufacturers the opportunity of rapid and custom production capability of parts such as molds, inserts, tools, subassemblies and even final products. Hence, the term Rapid Manufacturing (RM) has been added to the terminology. It is unlikely that RM will replace mass-manufacturing techniques in the near future due to some constraints. However, for small lot productions, highly complex parts and increased customization demands by customers Rapid Manufacturing may be the answer. Today, more than thirty companies around the world manufacture RP systems with different capacities and features. Rapid Prototyping / Manufacturing system producers utilize different technologies that require different materials. In this environment, manufacturing companies experience serious difficulties in search of appropriate materials and corresponding technologies for their use. This paper is aimed to present background on RP/RM technologies, current application fields of RM, comparison of RM with CNC (Computer Numerical Control) technology, and a critical view of most commonly utilized RM methods. Moreover, emphasis on RP/RM education complements the first portion of the paper with inclusion of Robert Morris University Engineering Department efforts to use RP/RM in engineering curriculum and expand technology awareness among current and prospective engineers.

Czajkiewicz, Zbigniew; Sirinterlikci, Arif; Uslu, Ozden

2012-03-29

293

Back to the future: inhaled drug products.  

PubMed

Inhaled therapeutic aerosols continue to be an important treatment for asthma and pulmonary diseases. A variety of dosage forms are employed for different indications and demographics including pressurized or propellant-driven metered dose inhalers, dry powder inhalers, and nebulizers/nebules. Research and development in this field has shown remarkable innovation in the past decade. Important new drug products for the treatment of asthma, chronic obstructive pulmonary disease, cystic fibrosis, diabetes, and a range of neurological disorders have been developed. New devices in each of the dosage form categories also have been developed, and new formulation technologies have been adopted. Unlike many other dosage forms, as new inhaled products appeared few of the existing products were converted to generic form. This may be explained by the formulation and device complexity, the implications for degree of difficulty in obtaining regulatory approval, and the prevalence of intellectual property in the field. After the setback of the initial approval and subsequent withdrawal of the Exubera-inhaled insulin, there appeared to be reluctance to consider the pulmonary route of administration for systemically acting agents, particularly peptides and proteins. However, recent product development activities and approvals suggest that attitudes may be changing in favor of systemic delivery following inhaled aerosol administration. The new inhaled drug technologies seem to be driving reconsideration of therapeutic categories for indications that were of interest at the inception of modern inhaled drug therapy in the past century. We should embrace the opportunity to use new drugs and technologies to go back to the future! PMID:23381932

Hickey, Anthony J

2013-04-01

294

N2O release from agro-biofuel production negates global warming reduction by replacing fossil fuels  

NASA Astrophysics Data System (ADS)

The relationship, on a global basis, between the amount of N fixed by chemical, biological or atmospheric processes entering the terrestrial biosphere, and the total emission of nitrous oxide (N2O), has been re-examined, using known global atmospheric removal rates and concentration growth of N2O as a proxy for overall emissions. For both the pre-industrial period and in recent times, after taking into account the large-scale changes in synthetic N fertiliser production, we find an overall conversion factor of 3-5% from newly fixed N to N2O-N. We assume the same factor to be valid for biofuel production systems. It is covered only in part by the default conversion factor for "direct" emissions from agricultural crop lands (1%) estimated by IPCC (2006), and the default factors for the "indirect" emissions (following volatilization/deposition and leaching/runoff of N: 0.35-0.45%) cited therein. However, as we show in the paper, when additional emissions included in the IPCC methodology, e.g. those from livestock production, are included, the total may not be inconsistent with that given by our "top-down" method. When the extra N2O emission from biofuel production is calculated in "CO2-equivalent" global warming terms, and compared with the quasi-cooling effect of "saving" emissions of fossil fuel derived CO2, the outcome is that the production of commonly used biofuels, such as biodiesel from rapeseed and bioethanol from corn (maize), depending on N fertilizer uptake efficiency by the plants, can contribute as much or more to global warming by N2O emissions than cooling by fossil fuel savings. Crops with less N demand, such as grasses and woody coppice species, have more favourable climate impacts. This analysis only considers the conversion of biomass to biofuel. It does not take into account the use of fossil fuel on the farms and for fertilizer and pesticide production, but it also neglects the production of useful co-products. Both factors partially compensate each other. This needs to be analyzed in a full life cycle assessment.

Crutzen, P. J.; Mosier, A. R.; Smith, K. A.; Winiwarter, W.

2008-01-01

295

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

NASA Astrophysics Data System (ADS)

Water availability is one of the limiting factors for sustainable production of biofuel crops. A common method for determining crop water requirement is to multiply daily potential evapotranspiration (ETo) calculated from meteorological parameters by a crop coefficient (Kc) to obtain actual crop evapotranspiration (ETc). Remote sensing data can provide dynamic Kc values that better reflect plant water use. In this study, an algorithm is being developed to estimate sugarcane Kc using normalized difference vegetation index (NDVI) obtained from Landsat 7 satellite images. Crop canopy cover was measured with a handheld multispectral camera from two sugarcane fields at the Hawaiian Commercial & Sugar Company (HC&S) plantation during the Landsat 7 satellite overpass days. An Eddy Covariance (EC) tower system was set up within each of these two fields and gathered EC flux at a 30-minute interval. Reference evapotranspiration was calculated from the network of automated weather stations at HC&S plantation using a modified Penman equation. Crop canopy cover was highly correlated with satellite NDVI values. A linear relationship between NDVI and measured Kc was obtained. Satellite -based ETc maps of HC&S plantation were developed using the NDVI-based Kc values and reference ET from HC&S weather station network. The satellite-based ETc was compared and validated with field measurements of ET using Eddy Covariance tower. A series of satellite-based ETc maps were developed to indicate the water demand of sugarcane plants at HC&S plantation. These results validate the use of satellite imagery as a tool for estimation of ET of sugarcane plants in Maui, Hawaii.

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

2012-12-01

296

First generation biofuels compete.  

PubMed

Rising petroleum prices during 2005-2008, and passage of the 2007 U.S. Energy Independence and Security Act with a renewable fuel standard of 36 billion gallons of biofuels by 2022, encouraged massive investments in U.S. ethanol plants. Consequently, corn demand increased dramatically and prices tripled. This created a strong positive correlation between petroleum, corn, and food prices resulting in an outcry from U.S. consumers and livestock producers, and food riots in several developing countries. Other factors contributed to higher grain and food prices. Economic growth, especially in Asia, and a weaker U.S. dollar encouraged U.S. grain exports. Investors shifted funds into the commodity's future markets. Higher fuel costs for food processing and transportation put upward pressure on retail food prices. From mid-2008 to mid-2009, petroleum prices fell, the U.S. dollar strengthened, and the world economy entered a serious recession with high unemployment, housing market foreclosures, collapse of the stock market, reduced global trade, and a decline in durable goods and food purchases. Agricultural commodity prices declined about 50%. Biotechnology has had modest impacts on the biofuel sector. Seed corn with traits that help control insects and weeds has been widely adopted by U.S. farmers. Genetically engineered enzymes have reduced ethanol production costs and increased conversion efficiency. PMID:20601265

Martin, Marshall A

2010-11-30

297

Analysis of advanced biofuels.  

SciTech Connect

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.

Dec, John E.; Taatjes, Craig A.; Welz, Oliver; Yang, Yi

2010-09-01

298

Forest Products Industry of the Future  

SciTech Connect

Los Alamos Technical Associates, Inc (LATA) conducted an evaluation of the potential impact and value of a portion of the current portfolio of r&d projects supported by the Office of Industrial Technology and the Forest Products Industry of the Future. The mission of the evaluation was to (a) assess the potential impact of the projects to meet the critical goals of the industry as identified in the vision and roadmapping documents. (b) Evaluate the relationship between the current portfolio of projects and the Agenda 202 Implementation Plan. In addition, evaluate the relationship between the portfolio and the newly revised draft technology strategy being created by the industry. (c) Identify areas where current efforts are making significant progress towards meeting industry goals and identify areas where additional work my be required to meet these goals. (d) Make recommendations to the DOE and the Forest Products Industry on possible improvements in the portfolio and in the current methodology that DOE uses to assess potential impacts on its R&D activities.

Los Alamos Technical Associates, Inc

2002-05-01

299

Tradeoffs and Synergies between biofuel production and large solar infrastructure in deserts.  

PubMed

Solar energy installations in deserts are on the rise, fueled by technological advances and policy changes. Deserts, with a combination of high solar radiation and availability of large areas unusable for crop production are ideal locations for large solar installations. However, for efficient power generation, solar infrastructures use large amounts of water for construction and operation. We investigated the water use and greenhouse gas (GHG) emissions associated with solar installations in North American deserts in comparison to agave-based biofuel production, another widely promoted potential energy source from arid systems. We determined the uncertainty in our analysis by a Monte Carlo approach that varied the most important parameters, as determined by sensitivity analysis. We considered the uncertainty in our estimates as a result of variations in the number of solar modules ha(-1), module efficiency, number of agave plants ha(-1), and overall sugar conversion efficiency for agave. Further, we considered the uncertainty in revenue and returns as a result of variations in the wholesale price of electricity and installation cost of solar photovoltaic (PV), wholesale price of agave ethanol, and cost of agave cultivation and ethanol processing. The life-cycle analyses show that energy outputs and GHG offsets from solar PV systems, mean energy output of 2405 GJ ha(-1) year(-1) (5 and 95% quantile values of 1940-2920) and mean GHG offsets of 464 Mg of CO2 equiv ha(-1) year(-1) (375-562), are much larger than agave, mean energy output from 206 (171-243) to 61 (50-71) GJ ha(-1) year(-1) and mean GHG offsets from 18 (14-22) to 4.6 (3.7-5.5) Mg of CO2 equiv ha(-1) year(-1), depending upon the yield scenario of agave. Importantly though, water inputs for cleaning solar panels and dust suppression are similar to amounts required for annual agave growth, suggesting the possibility of integrating the two systems to maximize the efficiency of land and water use to produce both electricity and liquid fuel. A life-cycle analysis of a hypothetical colocation indicated higher returns per m(3) of water used than either system alone. Water requirements for energy production were 0.22 L MJ(-1) (0.28-0.19) and 0.42 L MJ(-1) (0.52-0.35) for solar PV-agave (baseline yield) and solar PV-agave (high yield), respectively. Even though colocation may not be practical in all locations, in some water-limited areas, colocated solar PV-agave systems may provide attractive economic incentives in addition to efficient land and water use. PMID:24467248

Ravi, Sujith; Lobell, David B; Field, Christopher B

2014-03-01

300

Biofuels Combustion  

NASA Astrophysics Data System (ADS)

This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly.

Westbrook, Charles K.

2013-04-01

301

Biofuels combustion.  

PubMed

This review describes major features of current research in renewable fuels derived from plants and from fatty acids. Recent and ongoing fundamental studies of biofuel molecular structure, oxidation reactions, and biofuel chemical properties are reviewed, in addition to combustion applications of biofuels in the major types of engines in which biofuels are used. Biofuels and their combustion are compared with combustion features of conventional petroleum-based fuels. Two main classes of biofuels are described, those consisting of small, primarily alcohol, fuels (particularly ethanol, n-butanol, and iso-pentanol) that are used primarily to replace or supplement gasoline and those derived from fatty acids and used primarily to replace or supplement conventional diesel fuels. Research efforts on so-called second- and third-generation biofuels are discussed briefly. PMID:23298249

Westbrook, Charles K

2013-01-01

302

YOKAYO BIOFUELS, INC. GRANT FOR IMPROVEMENTS AND EXPANSION OF  

E-print Network

YOKAYO BIOFUELS, INC. GRANT FOR IMPROVEMENTS AND EXPANSION OF AN EXISTING FACILITY INITIAL STUDY-11-601) to expand an existing biofuels production facility (Yokayo Biofuels, Inc.) located at 350 Orr: THE PROPOSED PROJECT: Yokayo Biofuels, Inc. is an existing biofuels facility located at 350 Orr Springs Road

303

Biological nitrogen fixation in sugar cane: A key to energetically viable biofuel production  

Microsoft Academic Search

The advantages of producing biofuels to replace fossil energy sources are derived from the fact that the energy accumulated in the biomass in captured directly from photosynthesis and is thus renewable, and that the cycle of carbon dioxide fixation by the crop, followed by burning of the fuel makes no overall contribution to atmospheric CO or, consequently, to global warming.

R. M. Boddey

1995-01-01

304

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

Microsoft Academic Search

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 2050% 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

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

2011-01-01

305

Production of Advanced Biofuels via Liquefaction - Hydrothermal Liquefaction Reactor Design: April 5, 2013  

SciTech Connect

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.

Knorr, D.; Lukas, J.; Schoen, P.

2013-11-01

306

Catalytic cracking of palm oil for the production of biofuels: Optimization studies  

Microsoft Academic Search

Oil palm is widely grown in Malaysia. Palm oil has attracted the attention of researchers to develop an environmentally friendly and high quality fuel, free of nitrogen and sulfur. In the present study, the catalytic cracking of palm oil to biofuel was studied over REY catalyst in a transport riser reactor at atmospheric pressure. The effect of reaction temperature (400500C),

Pramila Tamunaidu; Subhash Bhatia

2007-01-01

307

Application of monoclonal antibodies to investigate plant cell wall deconstruction for biofuels production  

E-print Network

Application of monoclonal antibodies to investigate plant cell wall deconstruction for biofuels, or microbes. Lignocellulosic biomass is typically pretreated prior to enzymatic hydrolysis to disrupt cell.1039/c1ee02112e To better understand how hydrothermal pretreatment reduces plant cell wall recalcitrance

California at Riverside, University of

308

Impacts of the production and consumption of biofuels on stratospheric ozone  

NASA Astrophysics Data System (ADS)

Biofuels are becoming increasingly popular sources of renewable energy as economic pressures and environmental consequences encourage the use of alternatives to fossil fuels. However, growing crops destined for use as biofuels incurs large N2O emissions associated with the use of nitrogen-based fertilizers. Besides being a greenhouse gas, N2O is also the primary source of stratospheric NOx (NO + NO2) which leads to stratospheric ozone depletion. In this paper, the potential effects on the ozone layer of a large-scale shift away from fossil fuel use to biofuels consumption over the 21st century are examined. Under such a scenario, global-mean column ozone decreases by 2.6 DU between 2010 and 2100 in contrast to a 0.7 DU decrease under a control simulation (the IPCC SRES B1 scenario for greenhouse gases) and a 9.1 DU increase under the more commonly used SRES A1B scenario. Two factors cause the decrease in ozone in the biofuels simulation: 1) large N2O emissions lead to faster rates of the ozone-depleting NOx cycles and; 2) reduced CO2 emissions (due to less fossil fuel burning) lead to relatively less stratospheric cooling over the 21st century, which decreases ozone abundances. Reducing CO2 emissions while neglecting to reduce N2O emissions could therefore be damaging to the ozone layer.

Revell, Laura E.; Bodeker, Greg E.; Huck, Petra E.; Williamson, Bryce E.

2012-05-01

309

Have Indirect Emissions from Biofuels Been Exaggerated?  

Microsoft Academic Search

The production of biofuels may lead to enhanced greenhouse gas (GHG) emissions from land to the atmosphere either by directly converting land to biofuel crops, or indirectly, by causing the displacement of food production and other land uses which then require additional land conversions. The importance of indirect GHG emissions from biofuel-related displacement of food production and other land uses

D. W. Kicklighter; A. Gurgel; J. M. Melillo; J. M. Reilly; T. Cronin; B. S. Felzer; S. Paltsev; C. A. Schlosser; A. P. Sokolov

2009-01-01

310

Engineering the Saccharomyces cerevisiae ?-oxidation pathway to increase medium chain fatty acid production as potential biofuel.  

PubMed

Fatty acid-derived biofuels and biochemicals can be produced in microbes using ?-oxidation pathway engineering. In this study, the ?-oxidation pathway of Saccharomyces cerevisiae was engineered to accumulate a higher ratio of medium chain fatty acids (MCFAs) when cells were grown on fatty acid-rich feedstock. For this purpose, the haploid deletion strain ?pox1 was obtained, in which the sole acyl-CoA oxidase encoded by POX1 was deleted. Next, the POX2 gene from Yarrowia lipolytica, which encodes an acyl-CoA oxidase with a preference for long chain acyl-CoAs, was expressed in the ?pox1 strain. The resulting ?pox1 [pox2+] strain exhibited a growth defect because the ?-oxidation pathway was blocked in peroxisomes. To unblock the ?-oxidation pathway, the gene CROT, which encodes carnitine O-octanoyltransferase, was expressed in the ?pox1 [pox2+] strain to transport the accumulated medium chain acyl-coAs out of the peroxisomes. The obtained ?pox1 [pox2+, crot+] strain grew at a normal rate. The effect of these genetic modifications on fatty acid accumulation and profile was investigated when the strains were grown on oleic acids-containing medium. It was determined that the engineered strains ?pox1 [pox2+] and ?pox1 [pox2+, crot+] had increased fatty acid accumulation and an increased ratio of MCFAs. Compared to the wild-type (WT) strain, the total fatty acid production of the strains ?pox1 [pox2+] and ?pox1 [pox2+, crot+] were increased 29.5% and 15.6%, respectively. The intracellular level of MCFAs in ?pox1 [pox2+] and ?pox1 [pox2+, crot+] increased 2.26- and 1.87-fold compared to the WT strain, respectively. In addition, MCFAs in the culture medium increased 3.29-fold and 3.34-fold compared to the WT strain. These results suggested that fatty acids with an increased MCFAs ratio accumulate in the engineered strains with a modified ?-oxidation pathway. Our approach exhibits great potential for transforming low value fatty acid-rich feedstock into high value fatty acid-derived products. PMID:24465440

Chen, Liwei; Zhang, Jianhua; Chen, Wei Ning

2014-01-01

311

Engineering the Saccharomyces cerevisiae ?-Oxidation Pathway to Increase Medium Chain Fatty Acid Production as Potential Biofuel  

PubMed Central

Fatty acid-derived biofuels and biochemicals can be produced in microbes using ?-oxidation pathway engineering. In this study, the ?-oxidation pathway of Saccharomyces cerevisiae was engineered to accumulate a higher ratio of medium chain fatty acids (MCFAs) when cells were grown on fatty acid-rich feedstock. For this purpose, the haploid deletion strain ?pox1 was obtained, in which the sole acyl-CoA oxidase encoded by POX1 was deleted. Next, the POX2 gene from Yarrowia lipolytica, which encodes an acyl-CoA oxidase with a preference for long chain acyl-CoAs, was expressed in the ?pox1 strain. The resulting ?pox1 [pox2+] strain exhibited a growth defect because the ?-oxidation pathway was blocked in peroxisomes. To unblock the ?-oxidation pathway, the gene CROT, which encodes carnitine O-octanoyltransferase, was expressed in the ?pox1 [pox2+] strain to transport the accumulated medium chain acyl-coAs out of the peroxisomes. The obtained ?pox1 [pox2+, crot+] strain grew at a normal rate. The effect of these genetic modifications on fatty acid accumulation and profile was investigated when the strains were grown on oleic acids-containing medium. It was determined that the engineered strains ?pox1 [pox2+] and ?pox1 [pox2+, crot+] had increased fatty acid accumulation and an increased ratio of MCFAs. Compared to the wild-type (WT) strain, the total fatty acid production of the strains ?pox1 [pox2+] and ?pox1 [pox2+, crot+] were increased 29.5% and 15.6%, respectively. The intracellular level of MCFAs in ?pox1 [pox2+] and ?pox1 [pox2+, crot+] increased 2.26- and 1.87-fold compared to the WT strain, respectively. In addition, MCFAs in the culture medium increased 3.29-fold and 3.34-fold compared to the WT strain. These results suggested that fatty acids with an increased MCFAs ratio accumulate in the engineered strains with a modified ?-oxidation pathway. Our approach exhibits great potential for transforming low value fatty acid-rich feedstock into high value fatty acid-derived products. PMID:24465440

Chen, Liwei; Zhang, Jianhua; Chen, Wei Ning

2014-01-01

312

Viability Studies of Biofuels Though biofuels (like ethanol) promise renewable "green" energy, these  

E-print Network

Viability Studies of Biofuels Though biofuels (like ethanol) promise renewable "green" energy cannot possibly meet U.S. energy demands, and current methods of biofuel production often consume as much energy as they produce. If biofuels are to be viable long-term energy solutions, we need new sources

Hill, Wendell T.

313

Sustainable biofuels from algae  

Microsoft Academic Search

There is currently great interest in microalgae as sources of renewable energy and biofuels. Many algae species have a high\\u000a lipid content and can be grown on non-arable land using alternate water sources such as seawater. This paper discusses in\\u000a detail the issue of sustainability of commercial-scale microalgae production of biofuels with particular focus on land, water,\\u000a nutrients (N and

Michael Armin Borowitzka; Navid Reza Moheimani

314

17 CFR 41.41 - Security futures products accounts.  

Code of Federal Regulations, 2012 CFR

17 Commodity and Securities Exchanges 1 2012-04-01 2012-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY...

2012-04-01

315

17 CFR 41.41 - Security futures products accounts.  

Code of Federal Regulations, 2013 CFR

17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY...

2013-04-01

316

17 CFR 41.41 - Security futures products accounts.  

Code of Federal Regulations, 2010 CFR

17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY...

2010-04-01

317

17 CFR 41.41 - Security futures products accounts.  

Code of Federal Regulations, 2011 CFR

17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY...

2011-04-01

318

17 CFR 41.41 - Security futures products accounts.  

17 Commodity and Securities Exchanges 2 2014-04-01 2014-04-01 false Security futures products accounts. 41.41 Section 41.41 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION (CONTINUED)...

2014-04-01

319

School of Engineering and Science Algae Biofuels  

E-print Network

School of Engineering and Science Algae Biofuels BY: Alessandro Faldi, Ph.D. Section Head is algae- based biofuels, which we believe could be a meaningful part of the energy mix in the future. Algae biofuels have potential to be an economically viable, low-net carbon transportation fuel

Fisher, Frank

320

Future craft: how digital media is transforming product design  

Microsoft Academic Search

The open and collective traditions of the interaction community have created new opportunities for product designers to engage in the social issues around industrial production. This paper introduces Future Craft, a design methodology which applies emerging digital tools and processes to product design toward new objects that are socially and environmentally sustainable. We present the results of teaching the Future

Leonardo Bonanni; Amanda J. Parkes; Hiroshi Ishii

2008-01-01

321

Fueling the Future with Fungal Genomics  

SciTech Connect

Fungi play important roles across the range of current and future biofuel production processes. From crop/feedstock health to plant biomass saccharification, enzyme production to bioprocesses for producing ethanol, higher alcohols or future hydrocarbon biofuels, fungi are involved. Research and development are underway to understand the underlying biological processes and improve them to make bioenergy production efficient on an industrial scale. Genomics is the foundation of the systems biology approach that is being used to accelerate the research and development efforts across the spectrum of topic areas that impact biofuels production. In this review, we discuss past, current and future advances made possible by genomic analyses of the fungi that impact plant/feedstock health, degradation of lignocellulosic biomass and fermentation of sugars to ethanol, hydrocarbon biofuels and renewable chemicals.

Grigoriev, Igor V.; Cullen, Daniel; Hibbett, David; Goodwin, Stephen B.; Jeffries, Thomas W.; Kubicek, Christian P.; Kuske, Cheryl; Magnuson, Jon K.; Martin, Francis; Spatafora, Joey; Tsang, Adrian; Baker, Scott E.

2011-04-29

322

Viscous effects in the acoustic manipulation of algae for biofuel production  

Microsoft Academic Search

Microalgae are emerging as a promising source for environmentally friendly biofuels. Acoustic manipulation of algal cells\\u000a using standing waves is a relatively new method for dewatering and\\/or sorting algae harvests. Recent work in the field has\\u000a shown that acoustic dewatering methods may be more efficient and economical than traditional methods. Optimization of acoustic\\u000a algal cell manipulation requires a knowledge of

Cara A. C. Leckey; Mark K. Hinders

323

An Assessment of Land Availability and Price in the Coterminous United States for Conversion to Algal Biofuel Production  

SciTech Connect

Realistic economic assessment of land-intensive alternative energy sources (e.g., solar, wind, and biofuels) requires information on land availability and price. Accordingly, we created a comprehensive, national-scale model of these parameters for the United States. For algae-based biofuel, a minimum of 1.04E+05 km2 of land is needed to meet the 2022 EISA target of 2.1E+10 gallons year-1. We locate and quantify land types best converted. A data-driven model calculates the incentive to sell and a fair compensation value (real estate and lost future income). 1.02E+6 km2 of low slope, non-protected land is relatively available including croplands, pasture/ grazing, and forests. Within this total there is 2.64E+5 km2 of shrub and barren land available. The Federal government has 7.68E+4 km2 available for lease. Targeting unproductive lands minimizes land costs and impacts to existing industries. However, shrub and barren lands are limited by resources (water) and logistics, so land conversion requires careful consideration.

Venteris, Erik R.; Skaggs, Richard; Coleman, Andre M.; Wigmosta, Mark S.

2012-12-01

324

Assessment of Peruvian Biofuel Resources and Alternatives.  

National Technical Information Service (NTIS)

Comprehensive assessment of the biofuel potential of Peru is based on: determination of current biofuel utilization practices, evauation of Peruvian biomass productivity, identification of Peruvian agricultural and forestry resources, assessment of resour...

J. P. Harper, W. Smith, E. Mariani

1979-01-01

325

Carbon Cycling from Biofuel Crop Production in the Mid-Continental U. S. Region Predicted from MODIS Satellite Data and Ecosystem Modeling  

NASA Astrophysics Data System (ADS)

The NASA-CASA (Carnegie Ames Stanford Approach) simulation model based on satellite observations of monthly vegetation cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) was used to estimate biomass production from croplands across the states of Iowa and Nebraska (United States) over the period 2001-2004. Adjustments for light-use efficiency and water use in biofuel (both corn and perennial grass) crops were carried out across the region, resulting in a new mapping of aboveground and belowground carbon pools based on 500-meter resolution MODIS satellite data. Simulations of plant residue management and soil carbon decomposition were conducted in the NASA-CASA model during and following conversions to biofuel crops to track the fate of carbon pools and the emissions of greenhouse gases. Initial results are being compared to biofuel production reports from southern Iowa for model calibration and validation. The long-term aims of this research are to enhance understanding of the effects of biofuel feedstocks on the biogeochemical cycling of carbon, nitrogen, and water by bringing NASA satellite data sets to bear on the problems of tracking cropland production trends and shifts in different cover areas of native vegetation and biofuel crops.

Hiatt, S.; Potter, C.; Klooster, S.

2008-12-01

326

A New Biofuels Technology Blooms in Iowa  

ScienceCinema

Cellulosic biofuels made from agricultural waste have caught the attention of many farmers and could be the next revolution in renewable biofuels production. This video shows how an innovative technology that converts waste products from the corn harvest into renewable biofuels will help the U.S. produce billions of gallons of cellulosic biofuels over the coming decade. It will also stimulate local economies and reduce U.S. dependence on foreign oil.

Mathisen, Todd; Bruch, Don;

2013-05-29

327

Biofuels and Biotechnology  

SciTech Connect

The world obtains 86% of its energy from fossil fuels, 40% from petroleum, a majority of which goes to the transportation sector (www.IEA.gov). Well-recognized alternatives are fuels derived from renewable sources known as biofuels. There are a number of biofuels useful for transportation fuels, which include ethanol, biobutanol, mixed alcohols, biodiesel, and hydrogen. These biofuels are produced from biologically derived feedstock, almost exclusively being plant materials, either food or feed sources or inedible plant material called biomass. This chapter will discuss technologies for production of liquid transportation biofuels from renewable feedstocks, but hydrogen will not be included, as the production technology and infrastructure are not near term. In addition, a specific emphasis will be placed upon the research opportunities and potential for application of system biology tools to dissect and understand the biological processes central to production of these biofuels from biomass and biological materials. There are a number of technologies for production of each of these biofuels that range from fully mature processes such as grain-derived ethanol, emerging technology of ethanol form cellulose derived ethanol and immature processes such thermochemical conversion technologies and production of hydrogen all produced from renewable biological feedstocks. Conversion of biomass by various thermochemical and combustion technologies to produce thermochemical biodiesel or steam and electricity provide growing sources of bioenergy. However, these technologies are outside of the scope of this chapter, as is the use of biological processing for upgrading and conversion of fossil fuels. Therefore, this chapter will focus on the current status of production of biofuels produced from biological-derived feedstocks using biological processes. Regardless of the status of development of the biological process for production of the biofuels, each process can benefit from research and resulting development activities using the latest biological research tools and techniques. Among the most recently evolving research tools is what is collectively known as "omics" techniques such as genomics, transcriptomics, proteomics, metabolomics, and fluxomics, plus an ever growing omics word generation . These and other similar methodologies are central to understanding the interactive functioning of gene expression, resulting protein/enzyme production, which impacts the cellular metabolism, and carbon and metabolite flow. These system biology "omics" tools are beginning to be applied to understand and improve the biological processes involved in conversion of renewable plant and animal material to biofuels which will be discussed in this chapter.

Mielenz, Jonathan R [ORNL

2009-01-01

328

Solar-powered aeration and disinfection, anaerobic co-digestion, biological CO2 scrubbing and biofuel production: the energy and carbon management opportunities of waste stabilisation ponds.  

PubMed

Waste stabilisation pond (WSP) technology offers some important advantages and interesting possibilities when viewed in the light of sustainable energy and carbon management. Pond systems stand out as having significant advantages due to simple construction; low (or zero) operating energy requirements; and the potential for bio-energy generation. Conventional WSP requires little or no electrical energy for aerobic treatment as a result of algal photosynthesis. Sunlight enables WSP to disinfect wastewaters very effectively without the need for any chemicals or electricity consumption and their associated CO(2) emissions. The energy and carbon emission savings gained over electromechanical treatment systems are immense. Furthermore, because algal photosynthesis consumes CO(2), WSP can be utilised as CO(2) scrubbers. The environmental and financial benefits of pond technology broaden further when considering the low-cost, energy production opportunities of anaerobic ponds and the potential of algae as a biofuel. As we assess future best practice in wastewater treatment technology, perhaps one of the greatest needs is an improved consideration of the carbon footprint and the implications of future increases in the cost of electricity and the value of biogas. PMID:18653962

Shilton, A N; Mara, D D; Craggs, R; Powell, N

2008-01-01

329

Biofuels: Report to Congress  

EPA Science Inventory

Section 204 of the Energy Independence and Security Act of 2007 (EISA 2007) requires EPA to assess and report to Congress on the impacts to date and likely future impacts of the increased use of biofuels as required by the Clean Air Act, section 211(0). Environmental issues (...

330

Comparative energetics and kinetics of autotrophic lipid and starch metabolism in chlorophytic microalgae: implications for biomass and biofuel production  

PubMed Central

Due to the growing need to provide alternatives to fossil fuels as efficiently, economically, and sustainably as possible there has been growing interest in improved biofuel production systems. Biofuels produced from microalgae are a particularly attractive option since microalgae have production potentials that exceed the best terrestrial crops by 2 to 10-fold. In addition, autotrophically grown microalgae can capture CO2 from point sources reducing direct atmospheric greenhouse gas emissions. The enhanced biomass production potential of algae is attributed in part to the fact that every cell is photosynthetic. Regardless, overall biological energy capture, conversion, and storage in microalgae are inefficient with less than 8% conversion of solar into chemical energy achieved. In this review, we examine the thermodynamic and kinetic constraints associated with the autotrophic conversion of inorganic carbon into storage carbohydrate and oil, the dominant energy storage products in Chlorophytic microalgae. We discuss how thermodynamic restrictions including the loss of fixed carbon during acetyl CoA synthesis reduce the efficiency of carbon accumulation in lipids. In addition, kinetic limitations, such as the coupling of proton to electron transfer during plastoquinone reduction and oxidation and the slow rates of CO2 fixation by Rubisco reduce photosynthetic efficiency. In some cases, these kinetic limitations have been overcome by massive increases in the numbers of effective catalytic sites, e.g. the high Rubisco levels (mM) in chloroplasts. But in other cases, including the slow rate of plastoquinol oxidation, there has been no compensatory increase in the abundance of catalytically limiting protein complexes. Significantly, we show that the energetic requirements for producing oil and starch relative to the recoverable energy stored in these molecules are very similar on a per carbon basis. Presently, the overall rates of starch and lipid synthesis in microalgae are very poorly characterized. Increased understanding of the kinetic constraints of lipid and starch synthesis, accumulation and turnover would facilitate the design of improved biomass production systems. PMID:24139286

2013-01-01

331

Comparative energetics and kinetics of autotrophic lipid and starch metabolism in chlorophytic microalgae: implications for biomass and biofuel production.  

PubMed

Due to the growing need to provide alternatives to fossil fuels as efficiently, economically, and sustainably as possible there has been growing interest in improved biofuel production systems. Biofuels produced from microalgae are a particularly attractive option since microalgae have production potentials that exceed the best terrestrial crops by 2 to 10-fold. In addition, autotrophically grown microalgae can capture CO2 from point sources reducing direct atmospheric greenhouse gas emissions. The enhanced biomass production potential of algae is attributed in part to the fact that every cell is photosynthetic. Regardless, overall biological energy capture, conversion, and storage in microalgae are inefficient with less than 8% conversion of solar into chemical energy achieved. In this review, we examine the thermodynamic and kinetic constraints associated with the autotrophic conversion of inorganic carbon into storage carbohydrate and oil, the dominant energy storage products in Chlorophytic microalgae. We discuss how thermodynamic restrictions including the loss of fixed carbon during acetyl CoA synthesis reduce the efficiency of carbon accumulation in lipids. In addition, kinetic limitations, such as the coupling of proton to electron transfer during plastoquinone reduction and oxidation and the slow rates of CO2 fixation by Rubisco reduce photosynthetic efficiency. In some cases, these kinetic limitations have been overcome by massive increases in the numbers of effective catalytic sites, e.g. the high Rubisco levels (mM) in chloroplasts. But in other cases, including the slow rate of plastoquinol oxidation, there has been no compensatory increase in the abundance of catalytically limiting protein complexes. Significantly, we show that the energetic requirements for producing oil and starch relative to the recoverable energy stored in these molecules are very similar on a per carbon basis. Presently, the overall rates of starch and lipid synthesis in microalgae are very poorly characterized. Increased understanding of the kinetic constraints of lipid and starch synthesis, accumulation and turnover would facilitate the design of improved biomass production systems. PMID:24139286

Subramanian, Sowmya; Barry, Amanda N; Pieris, Shayani; Sayre, Richard T

2013-01-01

332

Glycogen production for biofuels by the euryhaline cyanobacteria Synechococcus sp. strain PCC 7002 from an oceanic environment  

PubMed Central

Background Oxygenic photosynthetic microorganisms such as cyanobacteria and microalgae have attracted attention as an alternative carbon source for the next generation of biofuels. Glycogen abundantly accumulated in cyanobacteria is a promising feedstock which can be converted to ethanol through saccharification and fermentation processes. In addition, the utilization of marine cyanobacteria as a glycogen producer can eliminate the need for a freshwater supply. Synechococcus sp. strain PCC 7002 is a fast-growing marine coastal euryhaline cyanobacteria, however, the glycogen yield has not yet been determined. In the present study, the effects of light intensity, CO2 concentration, and salinity on the cell growth and glycogen content were investigated in order to maximize glycogen production in Synechococcus sp. strain PCC 7002. Results The optimal culture conditions for glycogen production in Synechococcus sp. strain PCC 7002 were investigated. The maximum glycogen production of 3.5gL?1 for 7days (a glycogen productivity of 0.5gL?1 d?1) was obtained under a high light intensity, a high CO2 level, and a nitrogen-depleted condition in brackish water. The glycogen production performance in Synechococcus sp. strain PCC 7002 was the best ever reported in the ?-polyglucan (glycogen or starch) production of cyanobacteria and microalgae. In addition, the robustness of glycogen production in Synechococcus sp. strain PCC 7002 to salinity was evaluated in seawater and freshwater. The peak of glycogen production of Synechococcus sp. strain PCC 7002 in seawater and freshwater were 3.0 and 1.8gL?1 in 7days, respectively. Glycogen production in Synechococcus sp. strain PCC 7002 maintained the same level in seawater and half of the level in freshwater compared with the optimal result obtained in brackish water. Conclusions We conclude that Synechococcus sp. strain PCC 7002 has high glycogen production activity and glycogen can be provided from coastal water accompanied by a fluctuation of salinity. This work supports Synechococcus sp. strain PCC 7002 as a promising carbohydrate source for biofuel production. PMID:24959200

2014-01-01

333

Improving the feasibility of producing biofuels from microalgae using wastewater.  

PubMed

Biofuels have received much attention recently owing to energy consumption and environmental concerns. Despite many of the technologies being technically feasible, the processes are often too costly to be commercially viable. The major stumbling block to full-scale production of algal biofuels is the cost of upstream and downstream processes and environmental impacts such as water footprint and indirect greenhouse gas emissions from chemical nutrient production. The technoeconomics of biofuels production from microalgae is currently unfeasible due to the cost of inputs and productivities achieved. The use of a biorefinery approach sees the production costs reduced greatly due to utilization of waste streams for cultivation and the generation of several potential energy sources and value-added products while offering environmental protection. The use of wastewater as a production media, coupled with CO2 sequestration from flue gas greatly reduces the microalgal cultivation costs. Conversion of residual biomass and by-products, such as glycerol, for fuel production using an integrated approach potentially holds the key to near future commercial implementation of biofuels production. PMID:24350433

Rawat, I; Bhola, V; Kumar, R Ranjith; Bux, F

2013-01-01

334

Corn stover as a biofuel  

Microsoft Academic Search

Corn stover is one of several feedstocks being considered as a biofuel. Although corn stalks currently are not harvested routinely, the huge amount of biomass produced annually makes corn a potential commercial biofuel. Removal of crop residue from the field needs to balance against preventing soil erosion, maintaining soil organic matter levels, and preserving or enhancing productivity. After corn stover

J. Johnson; D. Reicosky; B. Sharratt; M. Lindstrom; W. Voorhees

335

Transporter-mediated biofuel secretion.  

PubMed

Engineering microorganisms to produce biofuels is currently among the most promising strategies in renewable energy. However, harvesting these organisms for extracting biofuels is energy- and cost-intensive, limiting the commercial feasibility of large-scale production. Here, we demonstrate the use of a class of transport proteins of pharmacological interest to circumvent the need to harvest biomass during biofuel production. We show that membrane-embedded transporters, better known to efflux lipids and drugs, can be used to mediate the secretion of intracellularly synthesized model isoprenoid biofuel compounds to the extracellular milieu. Transporter-mediated biofuel secretion sustainably maintained an approximate three- to fivefold boost in biofuel production in our Escherichia coli test system. Because the transporters used in this study belong to the ubiquitous ATP-binding cassette protein family, we propose their use as "plug-and-play" biofuel-secreting systems in a variety of bacteria, cyanobacteria, diatoms, yeast, and algae used for biofuel production. This investigation showcases the potential of expressing desired membrane transport proteins in cell factories to achieve the export or import of substances of economic, environmental, or therapeutic importance. PMID:23613592

Doshi, Rupak; Nguyen, Tuan; Chang, Geoffrey

2013-05-01

336

Transporter-mediated biofuel secretion  

PubMed Central

Engineering microorganisms to produce biofuels is currently among the most promising strategies in renewable energy. However, harvesting these organisms for extracting biofuels is energy- and cost-intensive, limiting the commercial feasibility of large-scale production. Here, we demonstrate the use of a class of transport proteins of pharmacological interest to circumvent the need to harvest biomass during biofuel production. We show that membrane-embedded transporters, better known to efflux lipids and drugs, can be used to mediate the secretion of intracellularly synthesized model isoprenoid biofuel compounds to the extracellular milieu. Transporter-mediated biofuel secretion sustainably maintained an approximate three- to fivefold boost in biofuel production in our Escherichia coli test system. Because the transporters used in this study belong to the ubiquitous ATP-binding cassette protein family, we propose their use as plug-and-play biofuel-secreting systems in a variety of bacteria, cyanobacteria, diatoms, yeast, and algae used for biofuel production. This investigation showcases the potential of expressing desired membrane transport proteins in cell factories to achieve the export or import of substances of economic, environmental, or therapeutic importance. PMID:23613592

Doshi, Rupak; Nguyen, Tuan; Chang, Geoffrey

2013-01-01

337

Method development for the characterization of biofuel intermediate products using gas chromatography with simultaneous mass spectrometric and flame ionization detections.  

PubMed

Accurate analytical methods are required to develop and evaluate the quality of new renewable transportation fuels and intermediate organic liquid products (OLPs). Unfortunately, existing methods developed for the detailed characterization of petroleum products, are not accurate for many of the OLPs generated from non-petroleum feedstocks. In this study, a method was developed and applied to the detailed characterization of complex OLPs formed during triacylglyceride (TG) pyrolysis which is the basis for generating one class of emerging biofuels. This method uses gas chromatography coupled simultaneously with flame ionization and mass spectrometry detectors (GC-FID/MS). The FID provided accurate quantification of carbonaceous species while MS enabled identification of unknown compounds. A programed temperature vaporizer using a 25 C, 0.1 min, 720 C min(-1), 350 C, 5 min temperature program is employed which minimizes compound discrimination better than the more commonly utilized split/splitless injector, as verified with injections at 250 and 350 C. Two standard mixtures featuring over 150 components are used for accurate identification and a designed calibration standard accounts for compound discrimination at the injector and differing FID responses of various classes of compounds. This new method was used to identify and quantify over 250 species in OLPs generated from canola oil, soybean oil, and canola methyl ester (CME). In addition to hydrocarbons, the method was used to quantify polar (upon derivatization) and unidentified species, plus the unresolved complex mixture that has not typically been determined in previous studies. Repeatability of the analytical method was below 5% RSD for all individual components. Using this method, the mass balance was closed for samples derived from canola and soybean oil but only ca. 77 wt% of the OLP generated from CME could be characterized. The ability to close the mass balance depended on sample origin, demonstrating the need for an accurate quantification method for biofuels at various stages of production. PMID:22245174

S?vov, Jana; Stahl, Danese C; Seames, Wayne S; Kubtov, Alena

2012-02-10

338

Mascoma Announces Major Cellulosic Biofuel Technology Breakthrough  

E-print Network

Mascoma Announces Major Cellulosic Biofuel Technology Breakthrough Lebanon, NH - May 7, 2009 bioprocessing, or CBP, a low-cost processing strategy for production of biofuels from cellulosic biomass. CBP much, much closer to billions of gallons of low cost cellulosic biofuels," said Michigan State

339

Overview on Biofuels from a European Perspective  

ERIC Educational Resources Information Center

In light of the recently developed European Union (EU) Biofuels Strategy, the literature is reviewed to examine (a) the coherency of biofuel production with the EU nonindustrial vision of agriculture, and (b) given its insufficient land base, the implications of a proposed bioenergy pact to grow biofuel crops in the developing world to meet EU

Ponti, Luigi; Gutierrez, Andrew Paul

2009-01-01

340

Assessing deforestation from biofuels: Methodological challenges  

Microsoft Academic Search

In this article, we attempt to find the spatial relations between deforestation and biofuel production at global level by analyzing available global deforestation and biofuels data, and find that, for a variety of reasons relating to data availability and its characteristics, and the way biofuels are produced, this task is extremely difficult if not virtually impossible. Then we bring down

Yan Gao; Margaret Skutsch; Rudi Drigo; Pablo Pacheco; Omar Masera

2011-01-01

341

Assessing the environmental sustainability of biofuels.  

PubMed

Biofuels vary in their potential to reduce greenhouse gas emissions when displacing fossil fuels. Savings depend primarily on the crop used for biofuel production, and on the effect that expanding its cultivation has on land use. Evidence-based policies should be used to ensure that maximal sustainability benefits result from the development of biofuels. PMID:25281367

Kazamia, Elena; Smith, Alison G

2014-10-01

342

Biofuels development and the policy regime.  

PubMed

Any major change to the energy order is certain to provoke both positive and negative societal responses. The current wave of biofuels development ignited controversies that have re-shaped the thinking about their future development. Mistakes were made in the early support for road transport biofuels in Organisation for Economic Co-operation and Development (OECD) countries. This article examines some of the policies that shaped the early development of biofuels and looks to the future. PMID:23174283

Philp, Jim C; Guy, Ken; Ritchie, Rachael J

2013-01-01

343

Utilization of macro-algae for enhanced CO 2 fixation and biofuels production: Development of a computing software for an LCA study  

Microsoft Academic Search

A Life Cycle Assessment study was carried out for evaluating the potential of utilizing marine biomass for energy production. Macro-algae obtained from the Adriatic and Jonian seas have been selected and tested for our initial case. Different techniques (supercritical CO2, organic solvents, and pyrolysis) were utilized in this study for the extraction of biofuel. Supercritical CO2 appears to be the

Michele ArestaT; Angela Dibenedetto; Grazia Barberio

2005-01-01

344

Experimental study for growth potential of unicellular alga Chlorella pyrenoidosa on dairy waste water: an integrated approach for treatment and biofuel production.  

PubMed

This communication presents an integrated approach to study the potential of Chlorella pyrenoidosa for treatment of dairy wastewater (DWW) and biofuel extraction. The experiment was set up in two steps. The step-1 of the experiment was designed for treatment of dairy wastewater. The physical and chemical parameters of wastewater quality such as nitrate, phosphate, chloride, fluoride, hardness, etc., were studied. The level of nitrate and phosphate known, agents of eutrophication in water bodies was reduced by 60% and 87% in influent, 49% and 83% in the effluent, respectively. The step-2 of the experiment was designed for biofuel extraction by harvesting the biomass (algal strain) grown in dairy waste water. The result of this study shows that algal strain C. pyrenoidosa is not only an agent for mitigation of pollutant load, but it can also be used as potential agent for biofuel production. PMID:22525258

Kothari, Richa; Pathak, Vinayak V; Kumar, Virendra; Singh, D P

2012-07-01

345

Assessment of the Projected One Billion Ton Biomass for Cellulosic Biofuel Production and Its Potential Implications on Regional Water Quality and Availability  

NASA Astrophysics Data System (ADS)

The DOE and USDA joint study, also commonly referred as the "Billion-Ton" study, assessed the cellulosic feedstock resources potential in the U.S. for producing second generation biofuel to replace 30 percent of the country's transportation fuels by year 2030. The available resource is expected to come from changing cropping pattern, increasing crop yield, harvesting agricultural and forest wood residues, and developing energy crops. Such large-scale changes in land use and crop managements are likely to affect the associated water quality and resources at both regional and local scales. To address the water sustainability associated with the projected biomass production in the Upper Mississippi River Basin (UMRB), we have developed a SWAT watershed model that simulate the changes in water quality (nitrogen, phosphorus, and soil erosion) and resources (soil water content, evapotranspiration, and runoff) of the region due to future biomass production scenario estimated by the Billion-Ton study. The scenario is implemented by changing the model inputs and parameters at subbasin and hydrologic response unit levels, as well as by improving the SWAT model to represent spatially varying crop properties. The potential impacts on water quality and water availability were compared with the results obtained from a baseline simulation which represents current watershed conditions and existing level of feedstock production. The basin level results suggested mixed effects on the water quality. The projected large-scale biomass production scenario is expected to decrease loadings of total nitrogen and nitrate in the streams while increase total phosphorus and suspended sediment. Results indicate an increase in the rate of evapotranspiration and a decrease in the soil water content and in surface runoff. discharge to the streams. The impacts at the subbasin or local scale varies spatially and temporally depending on the types of land use change, their locations, and crop managements, suggesting needs to further optimize the sustainable biomass production from water resource perspective at both regional and local levels.

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

2011-12-01

346

Biofuels: Policies, Standards and Technologies Officers of the World Energy Council  

E-print Network

Skyrocketing prices of crude oil in the middle of the first decade of the 21 st century accompanied by rising prices for food focused political and public attention on the role of biofuels. On the one hand, biofuels were considered as a potential automotive fuel with a bright future, on the other hand, biofuels were accused of competing with food production for land. The truth must lie somewhere in-between and is strongly dependent on the individual circumstance in different countries and regions. As food and energy are closely interconnected and often compete with each other for other resources, such as water, the World Energy Council- following numerous requests of its

Pierre Gadonneix; De Castro; Norberto Franco De Medeiros; Richard Drouin; David Kim; Jorge Ferioli; Abubakar Sambo; Johannes Teyssen; Abbas Ali Naqi; Zhang Guobao; Christoph Frei

347

World Biofuels Study  

SciTech Connect

This report forms part of a project entitled 'World Biofuels Study'. The objective is to study world biofuel markets and to examine the possible contribution that biofuel imports could make to help meet the Renewable Fuel Standard (RFS) of the Energy Independence and Security Act of 2007 (EISA). The study was sponsored by the Biomass Program of the Assistant Secretary for Energy Efficiency and Renewable Energy (EERE), U.S. Department of Energy. It is a collaborative effort among the Office of Policy and International Affairs (PI), Department of Energy and Oak Ridge National Laboratory (ORNL), National Renewable Energy Laboratory (NREL) and Brookhaven National Laboratory (BNL). The project consisted of three main components: (1) Assessment of the resource potential for biofuel feedstocks such as sugarcane, grains, soybean, palm oil and lignocellulosic crops and development of supply curves (ORNL). (2) Assessment of the cost and performance of biofuel production technologies (NREL). (3) Scenario-based analysis of world biofuel markets using the ETP global energy model with data developed in the first parts of the study (BNL). This report covers the modeling and analysis part of the project conducted by BNL in cooperation with PI. The Energy Technology Perspectives (ETP) energy system model was used as the analytical tool for this study. ETP is a 15 region global model designed using the MARKAL framework. MARKAL-based models are partial equilibrium models that incorporate a description of the physical energy system and provide a bottom-up approach to study the entire energy system. ETP was updated for this study with biomass resource data and biofuel production technology cost and performance data developed by ORNL and NREL under Tasks 1 and 2 of this project. Many countries around the world are embarking on ambitious biofuel policies through renewable fuel standards and economic incentives. As a result, the global biofuel demand is expected to grow very rapidly over the next two decades, provided policymakers stay the course with their policy goals. This project relied on a scenario-based analysis to study global biofuel markets. Scenarios were designed to evaluate the impact of different policy proposals and market conditions. World biofuel supply for selected scenarios is shown in Figure 1. The reference case total biofuel production increases from 12 billion gallons of ethanol equivalent in 2005 to 54 billion gallons in 2020 and 83 billion gallons in 2030. The scenarios analyzed show volumes ranging from 46 to 64 billion gallons in 2020, and from about 72 to about 100 billion gallons in 2030. The highest production worldwide occurs in the scenario with high feedstock availability combined with high oil prices and more rapid improvements in cellulosic biofuel conversion technologies. The lowest global production is found in the scenario with low feedstock availability, low oil prices and slower technology progress.

Alfstad,T.

2008-10-01

348

Potential impacts of intensive cellulosic biofuel production on water quality and quantity in the Upper Coast Plain, US  

NASA Astrophysics Data System (ADS)

This study outlines a long-term project focused on impacts of short-rotation loblolly pine production as a biofuel feedstock. The project was initiated in 2009 and focused on the development of a baseline dataset developed from hydrometric, isotopic, and water quality monitoring of a set of small paired catchments. In the winter of 2013 a series of treatments, representing typical forest management strategies in the southeastern US were implemented, and monitoring will continue through 2018. The detailed monitoring program has resulted in a conceptual model of catchment hydrological function, which is being used to scale the observational evidence up to larger watershed scales. The presentation focuses primarily on these modeling results, with particular emphasis on the influence of short rotation harvest on groundwater recharge and stream water quantity over decadal scales.

Vache, K. B.; Jackson, C. R.; Bitew, M. M.; Blake, J.; McDonnell, J. J.; Griffiths, N.

2013-12-01

349

Fatty acid from the renewable sources: a promising feedstock for the production of biofuels and biobased chemicals.  

PubMed

With the depletion of the nonrenewable petrochemical resources and the increasing concerns of environmental pollution globally, biofuels and biobased chemicals produced from the renewable resources appear to be of great strategic significance. The present review described the progress in the biosynthesis of fatty acid and its derivatives from renewable biomass and emphasized the importance of fatty acid serving as the platform chemical and feedstock for a variety of chemicals. Due to the low efficient conversions of lignocellulosic biomass or carbon dioxide to fatty acid, we also put forward that rational strategies for the production of fatty acid and its derivatives should further derive from the consideration of whole bioprocess (pretreatment, saccharification, fermentation, separation), multiscale analysis and interdisciplinary combinations (omics, kinetics, metabolic engineering, synthetic biology, fermentation and so on). PMID:24361277

Liu, Hui; Cheng, Tao; Xian, Mo; Cao, Yujin; Fang, Fang; Zou, Huibin

2014-01-01

350

Shifting Lands: Exploring Kansas Farmer Decision-Making in an Era of Climate Change and Biofuels Production  

NASA Astrophysics Data System (ADS)

While farming has been the subject of frequent critical analysis with respect to its environmental impacts, including its greenhouse gas emissions, there has been relatively little consideration of the potentially positive role of agriculture in responding to a future greatly influenced by climate change. One possible realm for agriculture to contribute successfully to this future is through biofuels cultivation. This paper uses the state of Kansas as an example to examine factors that are influencing farmer decision-making during a time of heightened debates about climate and energy. Drawing on interviews with key informants and Kansas farmers, we apply and refine a conceptual model for understanding farmer decisions. We find that farmers have largely positive perceptions of the natural environment. Climate change, especially, is not a salient concern at this time. Factors that appear most likely to influence farmer decisions to adopt a new practice include the relative advantage of that practice and the ability to learn about and discuss it through existing social networks. Successful policy incentives must provide farmers with a continued sense of both independence and contribution to greater societal good.

White, Stacey Swearingen; Selfa, Theresa

2013-02-01

351

Shifting lands: exploring Kansas farmer decision-making in an era of climate change and biofuels production.  

PubMed

While farming has been the subject of frequent critical analysis with respect to its environmental impacts, including its greenhouse gas emissions, there has been relatively little consideration of the potentially positive role of agriculture in responding to a future greatly influenced by climate change. One possible realm for agriculture to contribute successfully to this future is through biofuels cultivation. This paper uses the state of Kansas as an example to examine factors that are influencing farmer decision-making during a time of heightened debates about climate and energy. Drawing on interviews with key informants and Kansas farmers, we apply and refine a conceptual model for understanding farmer decisions. We find that farmers have largely positive perceptions of the natural environment. Climate change, especially, is not a salient concern at this time. Factors that appear most likely to influence farmer decisions to adopt a new practice include the relative advantage of that practice and the ability to learn about and discuss it through existing social networks. Successful policy incentives must provide farmers with a continued sense of both independence and contribution to greater societal good. PMID:23229828

White, Stacey Swearingen; Selfa, Theresa

2013-02-01

352

Product recall, brand equity, and future choice  

Microsoft Academic Search

The number of major product-recall incidents involving established brands have increased markedly over the last few years. Although the direct costs have been evaluated in these cases (typically in the millions), the indirect costs to brand equity and subsequent loss of market share are harder to evaluate. This paper applies a simulated multistage choice-based experiment to assess the impact of

Con Korkofingas; Lawrence Ang

2011-01-01

353

International Trade of Biofuels (Brochure)  

SciTech Connect

In recent years, the production and trade of biofuels has increased to meet global demand for renewable fuels. Ethanol and biodiesel contribute much of this trade because they are the most established biofuels. Their growth has been aided through a variety of policies, especially in the European Union, Brazil, and the United States, but ethanol trade and production have faced more targeted policies and tariffs than biodiesel. This fact sheet contains a summary of the trade of biofuels among nations, including historical data on production, consumption, and trade.

Not Available

2013-05-01

354

Water use implications of biofuel scenarios  

NASA Astrophysics Data System (ADS)

Existing studies rely upon attributional lifecycle analysis (LCA) approaches to estimate water intensity of biofuels in liters of irrigated/evapotranspiration water consumed for biofuel production. Such approaches can be misleading. From a policy perspective, a better approach is to compare differential water impacts among scenarios on a landscape scale. We address the shortcomings of existing studies by using consequential LCA, and incorporate direct and indirect land use (changes) of biofuel scenarios, marginal vs. average biofuel water use estimates, future climate, and geographic heterogeneity. We use the outputs of a partial equilibrium economic model, climate and soil data, and a process-based crop-soil-climate-water model to estimate differences in green water (GW - directly from precipitation to soil) and blue water (BW - supplied by irrigation) use among three scenarios: (1) business-as-usual (BAU), (2) Renewable Fuels Standard (RFS) mandates, and (3) a national Low Carbon Fuel Standard (LCFS) plus the RFS scenario. We use spatial statistical methods to interpolate key climatic variables using daily climate observations for the contiguous USA. Finally, we use FAO's crop model AquaCrop to estimate the domestic GW and BW impacts of biofuel policies from 2007-2035. We assess the differences among scenarios along the following metrics: (1) crop area expansion at the county level, including prime and marginal lands, (2) crop-specific and overall annual/seasonal water balances including (a) water inflows (irrigation & precipitation), (b) crop-atmosphere interactions: (evaporation & transpiration) and (d) soil-water flows (runoff & soil infiltration), in mm 3 /acre over the relevant time period. The functional unit of analysis is the BW and GW requirements of biofuels (mm3 per Btu biofuel) at the county level. Differential water use impacts among scenarios are a primarily a function of (1) land use conversion, in particular that of formerly uncropped land classes (2) irrigation practices, (3) feedstock water use efficiency, and (4) the longer growing season and a predominance of rainfed cultivation of dedicated biofuel feedstocks. National-level total water use is lowest in the BAU scenario and highest in the RFS2 + LCFS scenario. Figure: Million acres converted to growing miscanthus (top) & switchgrass (bottom) under the RFS + LCFS scenario in 2035. Land use classes are crop pasture (blue), idle cropland (red-purple) & prime cropland (brown).

Teter, J.; Mishra, G. S.; Yeh, S.

2012-12-01

355

Tailoring next-generation biofuels and their combustion in next-generation engines.  

SciTech Connect

Increasing energy costs, the dependence on foreign oil supplies, and environmental concerns have emphasized the need to produce sustainable renewable fuels and chemicals. The strategy for producing next-generation biofuels must include efficient processes for biomass conversion to liquid fuels and the fuels must be compatible with current and future engines. Unfortunately, biofuel development generally takes place without any consideration of combustion characteristics, and combustion scientists typically measure biofuels properties without any feedback to the production design. We seek to optimize the fuel/engine system by bringing combustion performance, specifically for advanced next-generation engines, into the development of novel biosynthetic fuel pathways. Here we report an innovative coupling of combustion chemistry, from fundamentals to engine measurements, to the optimization of fuel production using metabolic engineering. We have established the necessary connections among the fundamental chemistry, engine science, and synthetic biology for fuel production, building a powerful framework for co-development of engines and biofuels.

Gladden, John Michael; Wu, Weihua; Taatjes, Craig A.; Scheer, Adam Michael; Turner, Kevin M.; Yu, Eizadora T.; O'Bryan, Greg; Powell, Amy Jo; Gao, Connie W. [Massachusetts Institute of Technology, Cambridge, MA] [Massachusetts Institute of Technology, Cambridge, MA

2013-11-01

356

The future of bioconversion in energy production  

SciTech Connect

Man has used both thermal and bioconversion technologies for his purposes for the majority of recorded history. No doubt the first use of thermal technology was a fire to heat a cave while the first deliberate use of bioconversion occurred some time later when an discovered how to ferment sugar to make alcohol. While man used both the thermal and bioconversion technologies for his purposes, the majority of development was in the thermal technologies. Thermal reactions are quick (occur in fractions of seconds) occur in harsh conditions (elevated temperatures and pressures) and not precise (many products produced). Through history, biconversion was limited to natural plants and chemicals. These might be modified by natural selection, a long and imprecise process, but bioconversion processes while slow, occurred in mild conditions and were very precise. Not until 1948 when Watson defined DNA and life processes did mankind begin to understand and begin to use alter bioconversion technologies for his purpose. Bioconversion is on the brink of great expansion, from the production of drugs, vitamins, and food, to the production of bulk chemicals and fuels. The technology is at hand to speed up the reactions or to identify the active enzyme sites that will permit economic utilization of these emerging techniques.

Walter, D.K. [Department of Energy, Washington, DC (United States)

1993-12-31

357

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

Federal Register 2010, 2011, 2012, 2013

...4288 RIN 0570-AA75 Subpart B--Advanced Biofuel Payment Program; Correction AGENCY: Rural...a payment program for producers of advanced biofuels to supporting existing advanced biofuel production and to encourage new production...

2010-04-23

358

Utilization of Ash Fractions from Alternative Biofuels used in Power Plants  

E-print Network

Utilization of Ash Fractions from Alternative Biofuels used in Power Plants PSO Project No. 6356 July 2008 Renewable Energy and Transport #12;2 Utilization of Ash Fractions from Alternative Biofuels)...............................................................................7 2. Production of Ash Products from Mixed Biofuels

359

Engineered Respiro-Fermentative Metabolism for the Production of Biofuels and Biochemicals from Fatty Acid-Rich Feedstocks?  

PubMed Central

Although lignocellulosic sugars have been proposed as the primary feedstock for the biological production of renewable fuels and chemicals, the availability of fatty acid (FA)-rich feedstocks and recent progress in the development of oil-accumulating organisms make FAs an attractive alternative. In addition to their abundance, the metabolism of FAs is very efficient and could support product yields significantly higher than those obtained from lignocellulosic sugars. However, FAs are metabolized only under respiratory conditions, a metabolic mode that does not support the synthesis of fermentation products. In the work reported here we engineered several native and heterologous fermentative pathways to function in Escherichia coli under aerobic conditions, thus creating a respiro-fermentative metabolic mode that enables the efficient synthesis of fuels and chemicals from FAs. Representative biofuels (ethanol and butanol) and biochemicals (acetate, acetone, isopropanol, succinate, and propionate) were chosen as target products to illustrate the feasibility of the proposed platform. The yields of ethanol, acetate, and acetone in the engineered strains exceeded those reported in the literature for their production from sugars, and in the cases of ethanol and acetate they also surpassed the maximum theoretical values that can be achieved from lignocellulosic sugars. Butanol was produced at yields and titers that were between 2- and 3-fold higher than those reported for its production from sugars in previously engineered microorganisms. Moreover, our work demonstrates production of propionate, a compound previously thought to be synthesized only by propionibacteria, in E. coli. Finally, the synthesis of isopropanol and succinate was also demonstrated. The work reported here represents the first effort toward engineering microorganisms for the conversion of FAs to the aforementioned products. PMID:20525863

Dellomonaco, Clementina; Rivera, Carlos; Campbell, Paul; Gonzalez, Ramon

2010-01-01

360

Biofuels and Agriculture  

E-print Network

Biofuels and Agriculture Biofuels and Agriculture A Factsheet for Farmers American farmers have "biofuels" like ethanol and biodiesel mean that new markets are opening up. These can provide extra farm as growing markets for other biofuels like biodiesel. What are biofuels? Biofuels (short for "biomass fuels

Pawlowski, Wojtek

361

Biofuel impacts on water.  

SciTech Connect

Sandia National Laboratories and General Motors Global Energy Systems team conducted a joint biofuels systems analysis project from March to November 2008. The purpose of this study was to assess the feasibility, implications, limitations, and enablers of large-scale production of biofuels. 90 billion gallons of ethanol (the energy equivalent of approximately 60 billion gallons of gasoline) per year by 2030 was chosen as the book-end target to understand an aggressive deployment. Since previous studies have addressed the potential of biomass but not the supply chain rollout needed to achieve large production targets, the focus of this study was on a comprehensive systems understanding the evolution of the full supply chain and key interdependencies over time. The supply chain components examined in this study included agricultural land use changes, production of biomass feedstocks, storage and transportation of these feedstocks, construction of conversion plants, conversion of feedstocks to ethanol at these plants, transportation of ethanol and blending with gasoline, and distribution to retail outlets. To support this analysis, we developed a 'Seed to Station' system dynamics model (Biofuels Deployment Model - BDM) to explore the feasibility of meeting specified ethanol production targets. The focus of this report is water and its linkage to broad scale biofuel deployment.

Tidwell, Vincent Carroll; Malczynski, Leonard A.; Sun, Amy Cha-Tien

2011-01-01

362

Biofuels as Invasive Species  

E-print Network

In recent years, bioenergy has drawn attention as a sustainable energy source that may offer a viable alternative to declining fossil fuel sources. Governments are looking at the potential of highyielding crops for the production of biofuels to address shortages and to ameliorate the impacts of climate change. This approach has not been without controversy, especially in cases where food

unknown authors

363

Biofuels Overview CLIMATETECHBOOK  

E-print Network

.S. Fuel Ethanol Production, accessed May 10, 2009. http://www.ethanolrfa.org/industry/statistics the biofuel conversion process. Lignin yields energy when burned and further limits the fossil fuel inputs fuel that is produced from any plant- or animal-based feedstock (often referred to as "biomass

364

Fuel from wastewater : harnessing a potential energy source in Canada through the co-location of algae biofuel production to sources of effluent, heat and CO2.  

SciTech Connect

Sandia National Laboratories is collaborating with the National Research Council (NRC) Canada and the National Renewable Energy Laboratory (NREL) to develop a decision-support model that will evaluate the tradeoffs associated with high-latitude algae biofuel production co-located with wastewater, CO2, and waste heat. This project helps Canada meet its goal of diversifying fuel sources with algae-based biofuels. The biofuel production will provide a wide range of benefits including wastewater treatment, CO2 reuse and reduction of demand for fossil-based fuels. The higher energy density in algae-based fuels gives them an advantage over crop-based biofuels as the 'production' footprint required is much less, resulting in less water consumed and little, if any conversion of agricultural land from food to fuel production. Besides being a potential source for liquid fuel, algae have the potential to be used to generate electricity through the burning of dried biomass, or anaerobically digested to generate methane for electricity production. Co-locating algae production with waste streams may be crucial for making algae an economically valuable fuel source, and will certainly improve its overall ecological sustainability. The modeling process will address these questions, and others that are important to the use of water for energy production: What are the locations where all resources are co-located, and what volumes of algal biomass and oil can be produced there? In locations where co-location does not occur, what resources should be transported, and how far, while maintaining economic viability? This work is being funded through the U.S. Department of Energy (DOE) Biomass Program Office of Energy Efficiency and Renewable Energy, and is part of a larger collaborative effort that includes sampling, strain isolation, strain characterization and cultivation being performed by the NREL and Canada's NRC. Results from the NREL / NRC collaboration including specific productivities of selected algal strains will eventually be incorporated into this model.

Passell, Howard David; Whalen, Jake (SmartWhale Consulting, Dartmouth, NS, CA); Pienkos, Philip P. (National Renewable Energy Laboratory, Golden, CO); O'Leary, Stephen J. (National Research Council Canada, Institute for Marine Biosciences, Halifax, NS, CA); Roach, Jesse Dillon; Moreland, Barbara D.; Klise, Geoffrey Taylor

2010-12-01

365

Microwave pyrolysis of distillers dried grain with solubles (DDGS) for biofuel production  

SciTech Connect

Microwave pyrolysis of distillers dried grain with solubles (DDGS) was investigated to determine the effects of pyrolytic conditions on the yields of bio-oil, syngas, and biochar. Pyrolysis process variables included reaction temperature, time, and power input. Microwave pyrolysis of DDGS was analyzed using response surface methodology to ?nd out the effect of process variables on the biofuel (bio-oil and syn- gas) conversion yield and establish prediction models. Bio-oil recovery was in the range of 26.550.3 wt.% of the biomass. Biochar yields were 23.562.2% depending on the pyrolysis conditions. The energy con- tent of DDGS bio-oils was 28 MJ/kg obtained at the 650 oC and 8 min, which was about 66.7% of the heat- ing value of gasoline. GC/MS analysis indicated that the biooil contained a series of important and useful chemical compounds: aliphatic and aromatic hydrocarbons. At least 13% of DDGS bio-oil was the same hydrocarbon compounds found in regular unleaded gasoline.

Lei, Hanwu; Ren, Shoujie; Wang, Lu; Bu, Quan; Julson, James; Holladay, Johnathan E.; Ruan, Roger

2011-05-01

366

Use of algae as biofuel sources  

Microsoft Academic Search

The aim of this study is to investigate the algae production technologies such as open, closed and hybrid systems, production costs, and algal energy conversions. Liquid biofuels are alternative fuels promoted with potential to reduce dependence on fossil fuel imports. Biofuels production costs can vary widely by feedstock, conversion process, scale of production and region. Algae will become the most

Ayhan Demirbas

2010-01-01

367

Rural sector adapting to climate change - effects on future production  

Microsoft Academic Search

In this presentation we argue that there is growing evidence that Australia's climate will continue to change in the foreseeable future in ways that adversely affect agricultural production, requiring immediate and significant adaptation strategies. Most of the available evidence suggests that agricultural production is likely to be reduced by drier and warmer conditions projected for many of Australia's agricultural regions.

H. Meinke; Mark Howden; Andries Potgieter; Daniel Rodriguez

368

Midwest U.S. Landscape Change to 2020 Driven by Biofuel Mandates  

EPA Science Inventory

Meeting future biofuel targets set by the 2007 Energy Independence and Security Act (EISA), without a loss of animal feedstock or grain for human consumption, will require a substantial increase in production of corn. The Midwest, which has the highest overall crop production ap...

369

Predicting Agricultural Management Influence on Long-Term Soil Organic Carbon Dynamics: Implications for Biofuel Production  

SciTech Connect

Long-term field experiments (LTE) are ideal for predicting the influence of agricultural management on soil organic carbon (SOC) dynamics and examining biofuel crop residue removal policy questions. Our objectives were (i) to simulate SOC dynamics in LTE soils under various climates, crop rotations, fertilizer or organic amendments, and crop residue managements using the CQESTR model and (ii) to predict the potential of no-tillage (NT) management to maintain SOC stocks while removing crop residue. Classical LTEs at Champaign, IL (1876), Columbia, MO (1888), Lethbridge, AB (1911), Breton, AB (1930), and Pendleton, OR (1931) were selected for their documented history of management practice and periodic soil organic matter (SOM) measurements. Management practices ranged from monoculture to 2- or 3-yr crop rotations, manure, no fertilizer or fertilizer additions, and crop residue returned, burned, or harvested. Measured and CQESTR predicted SOC stocks under diverse agronomic practices, mean annual temperature (2.1 19 C), precipitation (402 973 mm), and SOC (5.89 33.58 g SOC kg 1) at the LTE sites were significantly related (r 2 = 0.94, n = 186, P < 0.0001) with a slope not significantly different than 1. The simulation results indicated that the quantities of crop residue that can be sustainably harvested without jeopardizing SOC stocks were influenced by initial SOC stocks, crop rotation intensity, tillage practices, crop yield, and climate. Manure or a cover crop/intensified crop rotation under NT are options to mitigate loss of crop residue C, as using fertilizer alone is insufficient to overcome residue removal impact on SOC stocks

Gollany, H. T. [USDA ARS; Rickman, R. W. [USDA ARS; Albrecht, S. L. [USDA ARS; Liang, Y. [University of Arkansas; Kang, Shujiang [ORNL; Machado, S. [Oregon State University, Corvallis

2011-01-01

370

Transcriptome sequencing and annotation of the microalgae Dunaliella tertiolecta: Pathway description and gene discovery for production of next-generation biofuels  

PubMed Central

Background Biodiesel or ethanol derived from lipids or starch produced by microalgae may overcome many of the sustainability challenges previously ascribed to petroleum-based fuels and first generation plant-based biofuels. The paucity of microalgae genome sequences, however, limits gene-based biofuel feedstock optimization studies. Here we describe the sequencing and de novo transcriptome assembly for the non-model microalgae species, Dunaliella tertiolecta, and identify pathways and genes of importance related to biofuel production. Results Next generation DNA pyrosequencing technology applied to D. tertiolecta transcripts produced 1,363,336 high quality reads with an average length of 400 bases. Following quality and size trimming, ~ 45% of the high quality reads were assembled into 33,307 isotigs with a 31-fold coverage and 376,482 singletons. Assembled sequences and singletons were subjected to BLAST similarity searches and annotated with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology (KO) identifiers. These analyses identified the majority of lipid and starch biosynthesis and catabolism pathways in D. tertiolecta. Conclusions The construction of metabolic pathways involved in the biosynthesis and catabolism of fatty acids, triacylglycrols, and starch in D. tertiolecta as well as the assembled transcriptome provide a foundation for the molecular genetics and functional genomics required to direct metabolic engineering efforts that seek to enhance the quantity and character of microalgae-based biofuel feedstock. PMID:21401935

2011-01-01

371

Third Generation Biofuels via Direct Cellulose Fermentation  

PubMed Central

Consolidated bioprocessing (CBP) is a system in which cellulase production, substrate hydrolysis, and fermentation are accomplished in a single process step by cellulolytic microorganisms. CBP offers the potential for lower biofuel production costs due to simpler feedstock processing, lower energy inputs, and higher conversion efficiencies than separate hydrolysis and fermentation processes, and is an economically attractive near-term goal for third generation biofuel production. In this review article, production of third generation biofuels from cellulosic feedstocks will be addressed in respect to the metabolism of cellulolytic bacteria and the development of strategies to increase biofuel yields through metabolic engineering. PMID:19325807

Carere, Carlo R.; Sparling, Richard; Cicek, Nazim; Levin, David B.

2008-01-01

372

Environmental implications of jatropha biofuel from a silvi-pastoral production system in central-west Brazil.  

PubMed

We present a life cycle assessment of synthetic paraffinic kerosene produced from Jatropha curcas. The feedstock is grown in an intercropping arrangement with pasture grasses so that Jatropha is coproduced with cattle. Additional innovations are introduced including hybrid seeds, detoxification of jatropha seedcake, and cogeneration. Two fuel pathways are examined including a newly developed catalytic decarboxylation process. Sensitivities are examined including higher planting density at the expense of cattle production as well as 50% lower yields. Intercropping with pasture and detoxifying seedcake yield coproducts that are expected to relieve pressure on Brazil's forests and indirectly reduce environmental impacts of biofuel production. Other innovations also reduce impacts. Results of the baseline assessment indicate that innovations would reduce impacts relative to the fossil fuel reference scenario in most categories including 62-75% reduction in greenhouse gas emissions, 64-82% reduction in release of ozone depleting chemicals, 33-52% reduction in smog-forming pollutants, 6-25% reduction in acidification, and 60-72% reduction in use of nonrenewable energy. System expansion, which explicitly accounts for avoided deforestation, results in larger improvements. Results are robust across allocation methodologies, improve with higher planting density, and persist if yield is reduced by half. PMID:23713609

Bailis, Rob; Kavlak, Goksin

2013-07-16

373

Present and future operational NOAA satellite oceanographic products: An introduction  

NASA Technical Reports Server (NTRS)

A review of operational satellite-derived National Oceanic and Atmospheric Administration/National Environment Satellite Service oceanographic products is presented and some current applications of these products are noted. Recent improvements to procedures used in deriving sea surface temperature observations and fields are described. Changes to data reduction techniques and products which will be incorporated with the advent of TIROS-N are outlined and some potential future developments are mentioned.

Kalinowski, J. K.; Signore, T. L.; Pichel, W. G.; Walton, C. C.; Brower, R. L.; Brown, S. R.; Bennekamper, K. G.

1977-01-01

374

Systems analysis and futuristic designs of advanced biofuel factory concepts.  

SciTech Connect

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.

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

2007-10-01

375

Biofuels for the gas turbine: A review  

Microsoft Academic Search

Due to depletion of fossil fuel, bio-fuels have generated a significant interest as an alternative fuel for the future. The use of bio-fuels to fuel gas turbine seems a viable solution for the problems of decreasing fossil-fuel reserves and environmental concerns. Bio-fuels are alternative fuels, made from renewable sources and having environmental benefit. In recent years, the desire for energy

K. K. Gupta; A. Rehman; R. M. Sarviya

2010-01-01

376

Algae as a sustainable energy source for biofuel production in Iran: A case study  

Microsoft Academic Search

Algae can be converted directly into energy, such as biodiesel, bioethanol and biomethanol and therefore can be a source of renewable energy. There is a growing interest for biodiesel production from algae because of its higher yield non-edible oil production and its fast growth that does not compete for land with food production. About 50% of algae weight is oil

Gholamhassan Najafi; Barat Ghobadian; Talal F. Yusaf

2011-01-01

377

Agriculture - Sustainable biofuels Redux  

SciTech Connect

Last May's passage of the 2008 Farm Bill raises the stakes for biofuel sustainability: A substantial subsidy for the production of cellulosic ethanol starts the United States again down a path with uncertain environmental consequences. This time, however, the subsidy is for both the refiners ($1.01 per gallon) and the growers ($45 per ton of biomass), which will rapidly accelerate adoption and place hard-to-manage pressures on efforts to design and implement sustainable production practices - as will a 2007 legislative mandate for 16 billion gallons of cellulosic ethanol per year by 2022. Similar directives elsewhere, e.g., the European Union's mandate that 10% of all transport fuel in Europe be from renewable sources by 2020, make this a global issue. The European Union's current reconsideration of this target places even more emphasis on cellulosic feedstocks (1). The need for knowledge- and science-based policy is urgent. Biofuel sustainability has environmental, economic, and social facets that all interconnect. Tradeoffs among them vary widely by types of fuels and where they are grown and, thus, need to be explicitly considered by using a framework that allows the outcomes of alternative systems to be consistently evaluated and compared. A cellulosic biofuels industry could have many positive social and environmental attributes, but it could also suffer from many of the sustainability issues that hobble grain-based biofuels, if not implemented the right way.

Robertson, G. Phillip [W.K. Kellogg Biological Station and Great Lakes Bioenergy Research; Dale, Virginia H [ORNL; Doering, Otto C. [Purdue University; Hamburg, Steven P [Brown University; Melillo, Jerry M [ORNL; Wander, Michele M [University of Illinois, Urbana-Champaign; Parton, William [Colorado State University, Fort Collins

2008-10-01

378

Modeling potential freshwater ecotoxicity impacts due to pesticide use in biofuel feedstock production: the cases of maize, rapeseed, salix, soybean, sugar cane, and wheat.  

PubMed

The inclusion of ecotoxicity impacts of pesticides in environmental assessments of biobased products has long been hampered by methodological challenges. We expanded the pesticide database and the regional coverage of the pesticide emission model PestLCI v.2.0, combined it with the impact assessment model USEtox, and assessed potential freshwater ecotoxicity impacts (PFEIs) of pesticide use in selected biofuel feedstock production cases, namely: maize (Iowa, US, two cases), rapeseed (Schleswig-Holstein, Germany), Salix (South Central Sweden), soybean (Mato Grosso, Brazil, two cases), sugar cane (So Paulo, Brazil), and wheat (Schleswig-Holstein, Germany). We found that PFEIs caused by pesticide use in feedstock production varied greatly, up to 3 orders of magnitude. Salix has the lowest PFEI per unit of energy output and per unit of cultivated area. Impacts per biofuel unit were 30, 750, and 1000 times greater, respectively, for the sugar cane, wheat and rapeseed cases than for Salix. For maize genetically engineered (GE) to resist glyphosate herbicides and to produce its own insecticidal toxin, maize GE to resist glyphosate, soybeans GE to resist glyphosate and conventional soybeans, the impacts were 110, 270, 305, and 310 times greater than for Salix, respectively. The significance of field and site-specific conditions are discussed, as well as options for reducing negative impacts in biofuel feedstock production. PMID:25207789

Nordborg, Maria; Cederberg, Christel; Berndes, Gran

2014-10-01

379

Reconstruction of the lipid metabolism for the microalga Monoraphidium neglectum from its genome sequence reveals characteristics suitable for biofuel production  

PubMed Central

Background Microalgae are gaining importance as sustainable production hosts in the fields of biotechnology and bioenergy. A robust biomass accumulating strain of the genus Monoraphidium (SAG 48.87) was investigated in this work as a potential feedstock for biofuel production. The genome was sequenced, annotated, and key enzymes for triacylglycerol formation were elucidated. Results Monoraphidium neglectum was identified as an oleaginous species with favourable growth characteristics as well as a high potential for crude oil production, based on neutral lipid contents of approximately 21% (dry weight) under nitrogen starvation, composed of predominantly C18:1 and C16:0 fatty acids. Further characterization revealed growth in a relatively wide pH range and salt concentrations of up to 1.0% NaCl, in which the cells exhibited larger structures. This first full genome sequencing of a member of the Selenastraceae revealed a diploid, approximately 68 Mbp genome with a G + C content of 64.7%. The circular chloroplast genome was assembled to a 135,362bp single contig, containing 67 protein-coding genes. The assembly of the mitochondrial genome resulted in two contigs with an approximate total size of 94kb, the largest known mitochondrial genome within algae. 16,761 protein-coding genes were assigned to the nuclear genome. Comparison of gene sets with respect to functional categories revealed a higher gene number assigned to the category carbohydrate metabolic process and in fatty acid biosynthetic process in M. neglectum when compared to Chlamydomonas reinhardtii and Nannochloropsis gaditana, indicating a higher metabolic diversity for applications in carbohydrate conversions of biotechnological relevance. Conclusions The genome of M. neglectum, as well as the metabolic reconstruction of crucial lipid pathways, provides new insights into the diversity of the lipid metabolism in microalgae. The results of this work provide a platform to encourage the development of this strain for biotechnological applications and production concepts. PMID:24373495

2013-01-01

380

17 CFR 41.24 - Rule amendments to security futures products.  

Code of Federal Regulations, 2010 CFR

...products. 41.24 Section 41.24 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION SECURITY FUTURES PRODUCTS Requirements and Standards for Listing Security Futures Products 41.24 Rule amendments to...

2010-04-01

381

17 CFR 41.25 - Additional conditions for trading for security futures products.  

Code of Federal Regulations, 2010 CFR

...conditions for trading for security futures products. 41.25 Section 41.25 Commodity...TRADING COMMISSION SECURITY FUTURES PRODUCTS Requirements and Standards for Listing Security Futures Products 41.25 Additional...

2010-04-01

382

Fuel from Wastewater - Harnessing a Potential Energy Source in Canada through the Co-location of Algae Biofuel Production to Sources of Effluent, Heat and CO2  

NASA Astrophysics Data System (ADS)

Sandia National Laboratories is collaborating with the National Research Council (NRC) Canada and the National Renewable Energy Laboratory (NREL) to develop a decision-support model that will evaluate the tradeoffs associated with high-latitude algae biofuel production co-located with wastewater, CO2, and waste heat. This project helps Canada meet its goal of diversifying fuel sources with algae-based biofuels. The biofuel production will provide a wide range of benefits including wastewater treatment, CO2 reuse and reduction of demand for fossil-based fuels. The higher energy density in algae-based fuels gives them an advantage over crop-based biofuels as the production footprint required is much less, resulting in less water consumed and little, if any conversion of agricultural land from food to fuel production. Besides being a potential source for liquid fuel, algae have the potential to be used to generate electricity through the burning of dried biomass, or anaerobically digested to generate methane for electricity production. Co-locating algae production with waste streams may be crucial for making algae an economically valuable fuel source, and will certainly improve its overall ecological sustainability. The modeling process will address these questions, and others that are important to the use of water for energy production: What are the locations where all resources are co-located, and what volumes of algal biomass and oil can be produced there? In locations where co-location does not occur, what resources should be transported, and how far, while maintaining economic viability? This work is being funded through the U.S. Department of Energy (DOE) Biomass Program Office of Energy Efficiency and Renewable Energy, and is part of a larger collaborative effort that includes sampling, strain isolation, strain characterization and cultivation being performed by the NREL and Canadas NRC. Results from the NREL / NRC collaboration including specific productivities of selected algal strains will eventually be incorporated into this model. Joint activities in algal biofuel research involving Sandia National Labs, NREL, and Canadas NRC are supported by the U.S. - Canada Clean Energy Dialogue Secretariat. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energys National Nuclear Security Administration under contract DE-AC04-94AL85000.

Klise, G. T.; Roach, J. D.; Passell, H. D.; Moreland, B. D.; O'Leary, S. J.; Pienkos, P. T.; Whalen, J.

2010-12-01

383

Evaluation of Microbial Communities from Extreme Environments as Inocula in a Carboxylate Platform for Biofuel Production from Cellulosic Biomass  

E-print Network

The carboxylate biofuels platform (CBP) involves the conversion of cellulosic biomass into carboxylate salts by a mixed microbial community. Chemical engineering approaches to convert these salts to a variety of fuels (diesel, gasoline, jet fuel...

Cope, Julia Lee

2013-08-06

384

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

E-print Network

The application of hydrophobic polymeric resins as solid-phase adsorbent materials for the recovery and purification of prospective second generation biofuel compounds, including ethanol, iso-propanol, n-propanol, iso-butanol, ...

Nielsen, David R.

385

Sustainable Liquid Biofuels in New Zealand: Can Sustainability Standards Help Distinguish the Good from the Bad?.  

E-print Network

??Concerns surrounding the environmental and social impacts of biofuel production have led to the rapid development of biofuel sustainability assessment schemes internationally. The New Zealand (more)

Grimmer, Natalie

2009-01-01

386

Identifying potential areas for biofuel production and evaluating the environmental effects: a case study of the James River Basin in the Midwestern United States  

USGS Publications Warehouse

Biofuels are now an important resource in the United States because of the Energy Independence and Security Act of 2007. Both increased corn growth for ethanol production and perennial dedicated energy crop growth for cellulosic feedstocks are potential sources to meet the rising demand for biofuels. However, these measures may cause adverse environmental consequences that are not yet fully understood. This study 1) evaluates the long-term impacts of increased frequency of corn in the crop rotation system on water quantity and quality as well as soil fertility in the James River Basin and 2) identifies potential grasslands for cultivating bioenergy crops (e.g. switchgrass), estimating the water quality impacts. We selected the soil and water assessment tool, a physically based multidisciplinary model, as the modeling approach to simulate a series of biofuel production scenarios involving crop rotation and land cover changes. The model simulations with different crop rotation scenarios indicate that decreases in water yield and soil nitrate nitrogen (NO3-N) concentration along with an increase in NO3-N load to stream water could justify serious concerns regarding increased corn rotations in this basin. Simulations with land cover change scenarios helped us spatially classify the grasslands in terms of biomass productivity and nitrogen loads, and we further derived the relationship of biomass production targets and the resulting nitrogen loads against switchgrass planting acreages. The suggested economically efficient (planting acreage) and environmentally friendly (water quality) planting locations and acreages can be a valuable guide for cultivating switchgrass in this basin. This information, along with the projected environmental costs (i.e. reduced water yield and increased nitrogen load), can contribute to decision support tools for land managers to seek the sustainability of biofuel development in this region.

Wu, Yiping; Liu, Shuguang; Li, Zhengpeng

2012-01-01

387

Development of integrated assessment platform for biofuels production via fast pyrolysis and upgrading pathway.  

E-print Network

??Growing concern over Greenhouse Gas (GHG) emissions from petroleum-based fuel consumption have prompted interest in the production of alternative transportation fuels from biorenewable sources. As (more)

Zhang, Yanan

2014-01-01

388

Biofuel Residues\\/Wastes: Ban or Boon?  

Microsoft Academic Search

Biofuel production generates significant amounts of low-value residues and wastes. This results in concern over sustainability of biofuel industry and its impact on environment. Bioconversion offers opportunities for economic utilization of biofuel residues and wastes with concomitant remediation of wastes. Due to their characteristics, these residues\\/wastes can serve as low-cost substrates for bioconversion to high-value products. Attempts have been made

SAOHARIT NITAYAVARDHANA; SAMIR KUMAR KHANAL

2011-01-01

389

Biofuel Residues\\/Wastes: Ban or Boon?  

Microsoft Academic Search

Biofuel production generates significant amounts of low-value residues and wastes. This results in concern over the sustainability of the biofuel industry and its impact on the environment. Bioconversion offers opportunities for the economic utilization of biofuel residues and wastes with concomitant remediation of wastes. Due to their characteristics, these residues\\/wastes can serve as low-cost substrates for bioconversion to high-value products.

SAOHARIT NITAYAVARDHANA; SAMIR KUMAR KHANAL

2012-01-01

390

Global Trends on the Processing of Biofuels  

Microsoft Academic Search

The aim of the present paper is to investigate bio-fuels produced from biomass materials by thermochemical and biochemical methods and the utilization trends of the products in the world. Bio-fuels are liquid or gaseous fuels made from plant matter and residues, such as agricultural crops, municipal wastes and agricultural and forestry by-products. Liquid bio-fuels being considered world over fall into

Mustafa Balat

2008-01-01

391

Indonesia: Bio-Fuels. Annual 2008. GAIN Report Number ID8016.  

National Technical Information Service (NTIS)

The government of Indonesia plans to develop a biofuel industry have stagnated. In 2008 biofuel production will, decrease compared to 2007 following the increase in oil and CPO prices and developed country policy. The government does not mandate biofuel u...

A. K. Bromokusumo

2008-01-01

392

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

Federal Register 2010, 2011, 2012, 2013

...Contract Proposals (NOCP) for the Advanced Biofuels Payment Program AGENCY: Rural Business-Cooperative...6 million to make payments to advanced biofuel producers for the production of eligible advanced biofuels. Of the $98.6 million, $68.6...

2013-06-11

393

Making Photosynthetic Biofuel Renewable: Recovering Phosphorus from Residual Biomass J. M. Gifford and P. Westerhoff  

E-print Network

Making Photosynthetic Biofuel Renewable: Recovering Phosphorus from Residual Biomass J. M. Gifford to global warming. Biofuel from phototrophic microbes like algae and bacteria provides a viable substitute improves biofuel sustainability by refining phosphorus recycling. Biomass Production Residual Biomass

Hall, Sharon J.

394

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

Federal Register 2010, 2011, 2012, 2013

...NOCP) for Payments to Eligible Advanced Biofuel Producers AGENCY: Rural Business-Cooperative...25 million to make payments to advanced biofuel producers for the production of eligible advanced biofuels in Fiscal Year 2012. The 2008 Farm...

2012-02-02

395

Transformation of Sorbitol to Biofuels by Heterogeneous Catalysis: Chemical and Industrial  

E-print Network

Transformation of Sorbitol to Biofuels by Heterogeneous Catalysis: Chemical and Industrial ainsi que des exemples d'applications industrielles. Abstract -- Transformation of Sorbitol to Biofuels and biodiesel production led to first generation biofuels. Nowadays, research is focused on lignocellulosic

Boyer, Edmond

396

A GIS COST MODEL TO ASSESS THE AVAILABILITY OF FRESHWATER, SEAWATER, AND SALINE GROUNDWATER FOR ALGAL BIOFUEL PRODUCTION IN THE UNITED STATES  

SciTech Connect

A key advantage of using microalgae for biofuel production is the ability of some algal strains to thrive in waters unsuitable for conventional crop irrigation such as saline groundwater or seawater. Nonetheless, the availability of sustainable water supplies will provide significant challenges for scale-up and development of algal biofuels. We conduct a limited techno-economic assessment based on the availability of freshwater, saline groundwater, and seawater for use in open pond algae cultivation systems. We explore water issues through GIS-based models of algae biofuel production, freshwater supply, and cost models for supplying seawater and saline groundwater. We estimate that combined, within the coterminous US these resources can support production on the order of 9.46E+7 m3 yr-1 (25 billion gallons yr-1) of renewable biodiesel. Achievement of larger targets requires the utilization of less water efficient sites and relatively expensive saline waters. Geographically, water availability is most favorable for the coast of the Gulf of Mexico and Florida peninsula, where evaporation relative to precipitation is moderate and various saline waters are economically available. As a whole, barren and scrub lands of the southwestern US have limited freshwater supplies so accurate assessment of alternative waters is critical.

Venteris, Erik R.; Skaggs, Richard; Coleman, Andre M.; Wigmosta, Mark S.

2013-03-15

397

Biofuels generation from sweet sorghum: Fermentative hydrogen production and anaerobic digestion of the remaining biomass  

Microsoft Academic Search

The present study focuses on the exploitation of sweet sorghum biomass as a source for hydrogen and methane. Fermentative hydrogen production from the sugars of sweet sorghum extract was investigated at different hydraulic retention times (HRT). The subsequent methane production from the effluent of the hydrogenogenic process and the methane potential of the remaining solids after the extraction process were

Georgia Antonopoulou; Hariklia N. Gavala; Ioannis V. Skiadas; K. Angelopoulos; Gerasimos Lyberatos

2008-01-01

398

Membrane processes for alcohol-water separation: Improving the energy efficiency of biofuel production  

EPA Science Inventory

The economics and environmental impact of producing fuels and chemicals biologically can be a strong function of the efficiency with which the fermentation products are removed from the biological media. Due to growth inhibition by some fermentation products, including ethanol an...

399

Modification of Lignin by Protein Cross-linking to Facilitate Production of Biofuels From Poplar  

SciTech Connect

The limited supply of fossil fuels and the associated environmental issues associated with their utilization has resulted in much effort put forth to promote renewable resources of energy. Switching to renewable fuels for energy will allow us to become carbon neutral by recycling carbon from plants and reduce carbon from dioxide emissions, which could potentially reduce global warming in future generations and generate new industries with exciting new technologies.

Tien, Ming [The Pennsylvania State University] [The Pennsylvania State University

2013-04-22

400

Mitigating Land Use Changes From Biofuel Expansion: An Assessment of Biofuel Feedstock Yield Potential in APEC Economies  

Microsoft Academic Search

The emerging biofuel sector has drawn great interest as an alternative source of fuel for transportation. The expansion of biofuels greatly impacts world agricultural markets, since currently, the primary feedstocks for ethanol and biodiesel production are field crops and their derived products. There is great interest in the potential of countries to expand their biofuel sectors through increased production of

Amani E. Elobeid; Simla Tokgoz; Tun-Hsiang Yu

2009-01-01

401

Energy Efficiency Analysis: Biomass-to-Wheel Efficiency Related with Biofuels Production, Fuel Distribution, and Powertrain Systems  

PubMed Central

Background Energy efficiency analysis for different biomass-utilization scenarios would help make more informed decisions for developing future biomass-based transportation systems. Diverse biofuels produced from biomass include cellulosic ethanol, butanol, fatty acid ethyl esters, methane, hydrogen, methanol, dimethyether, Fischer-Tropsch diesel, and bioelectricity; the respective powertrain systems include internal combustion engine (ICE) vehicles, hybrid electric vehicles based on gasoline or diesel ICEs, hydrogen fuel cell vehicles, sugar fuel cell vehicles (SFCV), and battery electric vehicles (BEV). Methodology/Principal Findings We conducted a simple, straightforward, and transparent biomass-to-wheel (BTW) analysis including three separate conversion elements -- biomass-to-fuel conversion, fuel transport and distribution, and respective powertrain systems. BTW efficiency is a ratio of the kinetic energy of an automobile's wheels to the chemical energy of delivered biomass just before entering biorefineries. Up to 13 scenarios were analyzed and compared to a base line case corn ethanol/ICE. This analysis suggests that BEV, whose electricity is generated from stationary fuel cells, and SFCV, based on a hydrogen fuel cell vehicle with an on-board sugar-to-hydrogen bioreformer, would have the highest BTW efficiencies, nearly four times that of ethanol-ICE. Significance In the long term, a small fraction of the annual US biomass (e.g., 7.1%, or 700 million tons of biomass) would be sufficient to meet 100% of light-duty passenger vehicle fuel needs (i.e., 150 billion gallons of gasoline/ethanol per year), through up to four-fold enhanced BTW efficiencies by using SFCV or BEV. SFCV would have several advantages over BEV: much higher energy storage densities, faster refilling rates, better safety, and less environmental burdens. PMID:21765941

Huang, Wei-Dong; Zhang, Y-H Percival

2011-01-01

402

Generating Phenotypic Diversity in a Fungal Biocatalyst to Investigate Alcohol Stress Tolerance Encountered during Microbial Cellulosic Biofuel Production  

PubMed Central

Consolidated bioprocessing (CBP) of lignocellulosic biomass offers an alternative route to renewable energy. The crop pathogen Fusarium oxysporum is a promising fungal biocatalyst because of its broad host range and innate ability to co-saccharify and ferment lignocellulose to bioethanol. A major challenge for cellulolytic CBP-enabling microbes is alcohol inhibition. This research tested the hypothesis that Agrobacterium tumefaciens - mediated transformation (ATMT) could be exploited as a tool to generate phenotypic diversity in F. oxysporum to investigate alcohol stress tolerance encountered during CBP. A random mutagenesis library of gene disruption transformants (n=1,563) was constructed and screened for alcohol tolerance in order to isolate alcohol sensitive or tolerant phenotypes. Following three rounds of screening, exposure of select transformants to 6% ethanol and 0.75% n-butanol resulted respectively in increased (?11.74%) and decreased (?43.01%) growth compared to the wild type (WT). Principal component analysis (PCA) quantified the level of phenotypic diversity across the population of genetically transformed individuals and isolated candidate strains for analysis. Characterisation of one strain, Tr. 259, ascertained a reduced growth phenotype under alcohol stress relative to WT and indicated the disruption of a coding region homologous to a putative sugar transporter (FOXG_09625). Quantitative PCR (RT-PCR) showed FOXG_09625 was differentially expressed in Tr. 259 compared to WT during alcohol-induced stress (P<0.05). Phylogenetic analysis of putative sugar transporters suggests diverse functional roles in F. oxysporum and other filamentous fungi compared to yeast for which sugar transporters form part of a relatively conserved family. This study has confirmed the potential of ATMT coupled with a phenotypic screening program to select for genetic variation induced in response to alcohol stress. This research represents a first step in the investigation of alcohol tolerance in F. oxysporum and has resulted in the identification of several novel strains, which will be of benefit to future biofuel research. PMID:24147009

Hennessy, Rosanna C.; Doohan, Fiona; Mullins, Ewen

2013-01-01

403

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

Microsoft Academic Search

There is currently a renewed interest in developing microalgae as a source of renewable energy and fuel. Microalgae hold great\\u000a potential as a source of biomass for the production of energy and fungible liquid transportation fuels. However, the technologies\\u000a required for large-scale cultivation, processing, and conversion of microalgal biomass to energy products are underdeveloped.\\u000a Microalgae offer several advantages over traditional

Patrick J. McGinn; Kathryn E. Dickinson; Shabana Bhatti; Jean-Claude Frigon; Serge R. Guiot; Stephen J. B. OLeary

404

Mineralization of Nitrogen from Biofuel By-products and Animal Manures Amended to a Sandy Soil  

Microsoft Academic Search

Transformations of nitrogen (N) from poultry litter (PL), dairy manure compost (DMC), anaerobically digested fiber (ADF), Perfect Blend 722 (PB), a compost\\/litter mixture (C\\/L), dried distillers grains from ethanol production (DG), and mustard meal from biodiesel production (MM) applied to a Quincy fine sand were investigated in an incubation experiment over 210 days. The cumulative release totals of available N

A. D. Moore; A. K. Alva; H. P. Collins; R. A. Boydston

2010-01-01

405

Single-top-quark production at future ep colliders  

Microsoft Academic Search

The production of top quarks in single mode at future ep colliders is studied, the attention being mainly focused to the case of the proposed CERN LEP?LHC collider. We are motivated to reanalyze such a process following the discovery of the top quark at Fermilab. Thanks to the measurement of its mass one is now able to establish more accurately

Stefano Moretti; Kosuke Odagiri

1998-01-01

406

Metabolic Engineering for Improved Biofuel Yield in a Marine  

E-print Network

Metabolic Engineering for Improved Biofuel Yield in a Marine Cyanobacterium/conclusion · future work that will be done to increase biofuel yield #12;Problems? · Many na@al renewable source of energy -Biofuel produc@on from aqua@c photoautotroph

Petta, Jason

407

Impact of air pollution control costs on the cost and spatial arrangement of cellulosic biofuel production in the U.S.  

PubMed

Air pollution emissions regulation can affect the location, size, and technology choice of potential biofuel production facilities. Difficulty in obtaining air pollutant emission permits and the cost of air pollution control devices have been cited by some fuel producers as barriers to development. This paper expands on the Geospatial Bioenergy Systems Model (GBSM) to evaluate the effect of air pollution control costs on the availability, cost, and distribution of U.S. biofuel production by subjecting potential facility locations within U.S. Clean Air Act nonattainment areas, which exceed thresholds for healthy air quality, to additional costs. This paper compares three scenarios: one with air quality costs included, one without air quality costs, and one in which conversion facilities were prohibited in Clean Air Act nonattainment areas. While air quality regulation may substantially affect local decisions regarding siting or technology choices, their effect on the system as a whole is small. Most biofuel facilities are expected to be sited near to feedstock supplies, which are seldom in nonattainment areas. The average cost per unit of produced energy is less than 1% higher in the scenarios with air quality compliance costs than in scenarios without such costs. When facility construction is prohibited in nonattainment areas, the costs increase by slightly over 1%, due to increases in the distance feedstock is transported to facilities in attainment areas. PMID:24467277

Murphy, Colin W; Parker, Nathan C

2014-02-18

408

Time reducing process for biofuel production from non edible oil assisted by ultrasonication.  

PubMed

Limited resources of conventional fuels such as petrodiesel have led to the search for alternative fuels. Various convention batch/continuous processes for the biodiesel production have been developed before the recent year. All processes are time consuming with high labor cost. Thus, we need a new process for biodiesel production which reduces the reaction time and production cost as well as save the energy. In this work, ultrasonic assisted transesterification of Jatrophacurcas oil is carried out in the presence of methanol and potassium hydroxide (KOH) as catalyst, keeping the molar ratio of oil to alcohol 1:5, catalyst concentration 0.75 wt% of oil, ultrasonic amplitude 50% and pulse 0.3 cycle, 7 min reaction time under atmospheric condition. Ultrasonic mixing has increased the rate of transesterification reaction as compare to the mechanical mixing. PMID:24792785

Kumar, Gajendra; Kumar, Dharmendra; Johari, Rajeev

2014-09-01

409

Biofuel on contaminated land  

NASA Astrophysics Data System (ADS)

Desktop studies of two Swedish contaminated sites has indicated that growing biofuel crops on these sites may be more environmentally beneficial than alternative risk management approaches such as excavation / removal or containment The demand for biofuel increases pressure on the cultivatable soil of the world. While contaminated land is not very suitable for food production, cultivation of low and medium contaminated soil may remove some pressure from agricultural soils. For larger sites, biofuel cultivation may be economically viable without a remediation bonus. Suitable sites have topographic conditions that allow agricultural machinery, are not in urgent need of remediation, and contamination levels are not plant toxic. Life cycle assessment (LCA) was done for two cases. The (desk top) case studies were - Case K, a 5000 m2 site where salix (willow) was cultivated with hand-held machinery and the biofuel harvest was left on site, and - Case F, a 12 ha site were on site ensuring was being considered, and were salix might have rented an economic profit if the remediation had not been urgent due to exploitation pressure. Some selected results for biofuel K; biofuel F; excavation K; and on site ensuring F respectively: Energy: 0,05; 1,4; 3,5; 19 TJ Waste: 1; 9; 1200; 340 ton Land use off-site: 190; 3 500; 200 000; 1 400 000 m a Global warming: 3; 86; 230; 1 200 ton CO2 eq Acidification: 25; 1 000; 2 600; 14 000 kg SO2 eq Photochemical smog: 10; 180; 410; 2 300 kg ethene eq Human health: 2; 51; 150; 620 index The environmental impact of the traditional remediation methods of excavation and on-site ensuring was mainly due to the transport of contaminated soil and replacement soil, and landfilling of the contaminated soil. Biofuel cultivation avoids these impacts, while fertiliser production and agricultural machinery would have a lower environmental impact than moving large volumes of soil around. Journeys of a controller to check on the groundwater quality also contributed to the biofuel impacts. The net CO2 equivalent emission on a 100 year basis per MJ energy in the Salix Vinimalis was between -0.02 and -0.1 kgCO2e/MJ. The fate of the stubble and roots of the salix was crucial for the carbon footprint. While stubble and roots remain in the soil (as increased soil organic matter), the carbon dioxide they took up while growing is not contributing to global warming. This pool was much larger than the CO2 emissions from soil transport and other processes. Biodiversity was difficult to include, and the results are uncertain. But the results indicated that biodiversity impact of biofuel cultivation may be large compared to "easier" categories like global warming and human health, and the net impact of biofuel cultivation may well be benifical to the environment instead of damaging.

Suer, Pascal; Andersson-Skld, Yvonne; Blom, Sonja; Bardos, Paul; Polland, Marcel; Track, Thomas

2010-05-01

410

Environmental Challenges with the Production of Biofuels in India and its Implications for Food Security  

Microsoft Academic Search

the world, 212 million or approximately 20% of the country's population. The most efficient way to reduce the number of undernourished people and generate a continual state of food security is to increase the sustainable productivity of subsistence family farmers in rural regions of the country. This accomplishes two tasks, first it ensures a stable source of food for these

Abhishek Vemuri

411

World crop residues production and implications of its use as a biofuel  

Microsoft Academic Search

Reducing and off-setting anthropogenic emissions of CO2 and other greenhouse gases (GHGs) are important strategies of mitigating the greenhouse effect. Thus, the need for developing carbon (C) neutral and renewable sources of energy is more than ever before. Use of crop residue as a possible source of feedstock for bioenergy production must be critically and objectively assessed because of its

R. Lal

2005-01-01

412

Jatropha curcas L. as a source for the production of biofuel in Nicaragua  

Microsoft Academic Search

The development of Jatropha curcas L. as a possible energy crop in Nicaragua is discussed. The energy situation in Nicaragua, the cultivation of Jatropha curcas, the description of the plant, the composition of the seeds, the specification of the oil and the expected yield of oil production is outlined. A technical process for the processing of the seeds and the

N. Foidl; G. Foidl; M. Sanchez; M. Mittelbach; S. Hackel

1996-01-01

413

AlgaeSim: a model for integrated algal biofuel production and wastewater treatment.  

PubMed

AlgaeSim, a dynamic multiple-systems (C, N, P) mass balance model, was developed to explore the potential for algae biomass production from wastewater by coupling two photobioreactors into the main treatment train at a municipal wastewater resource recovery facility (WRRF) in Tampa, Florida. The scoping model examined the synergy between algae cultivation and wastewater treatment through algal growth and substrate removal kinetics, as well as through macroeconomic analyses of biomass conversion to bioproducts. Sensitivity analyses showed that biomass production is strongly dependent on Monod variables and harvesting regime, with sensitivity changing with growth phase. Profitability was sensitive to processing costs and market prices of products. Under scenarios based on current market conditions and typical algae production, AlgaeSim shows that a WRRF can potentially generate significant profit if algae are processed for biodiesel, biogas, or fertilizer. Wastewater resource recovery facilities could similarly save on operating costs resulting from the reduction in aeration (for nitrification) and chemicals (for denitrification). PMID:24645547

Drexler, Ivy L C; Joustra, Caryssa; Prieto, Ana; Bair, Robert; Yeh, Daniel H

2014-02-01

414

Increasing algal biofuel production using Nannocholropsis oculata cultivated with anaerobically and aerobically treated swine wastewater.  

PubMed

For mass production of Nannocholropsis oculata, a cheap nutrition source such as swine wastewater is required. The use of a combination of anaerobically/aerobically treated swine wastewater (AnATSW) was compared to artificial 3f/2 medium in terms of algal growth rate and oil content. For microalgae cultured in 0-50% (v/v) AnATSW, a biomass of 0.94-3.22 g L(-1) was reached in 5 days. For microalgae cultured in 3f/2 medium with vitamins, the lipid productivity was 0.122 g L(-1) d(-1) although its oil content reached 48.9%. Culturing N. oculata in 0-50% AnATSW resulted in an optimal lipid productivity of 0.035-0.177 g L(-1) d(-1). Only vitamins improved algal production of more oxidatively stable compositions of unsaturated oils. These oils were similar to the chemical structure of rapeseed oil based on analysis of the bis-allylic-position-equivalent value (30.64-46.13) and the iodine value (90.5-117.46). These oils were similar to coal based on the calculated low-heating-value of 17.6-22.9 MJ/kg. PMID:23422305

Wu, Pei-Fen; Teng, Jui-Chin; Lin, Yun-Huin; Hwang, Sz-Chwun John

2013-04-01

415

Potential impacts of cropland biofuel production on the provision of avian habitat  

EPA Science Inventory

Present laws and policies encourage the growth of corn for the production of starch-based and cellulosic ethanol on agricultural lands in the U.S. This has been touted as an environmentally-friendly solution to problems of energy-independence, particularly in the midwestern U.S....

416

Impacts of land use change due to biofuel crops on carbon balance, bioenergy production, and agricultural  

E-print Network

and Brazil (Carriquiry et al., 2011). For fuel ethanol in the United States, production increased from less crops to Miscanthus, the per unit area croplands produced a larger amount of ethanol than crops or switchgrass, considering both economic and environmental benefits. Keywords: bioenergy, crop

Zhuang, Qianlai

417

Emissions from small-scale energy production using co-combustion of biofuel and the dry fraction of household waste  

SciTech Connect

In sparsely populated rural areas, recycling of household waste might not always be the most environmentally advantageous solution due to the total amount of transport involved. In this study, an alternative approach to recycling has been tested using efficient small-scale biofuel boilers for co-combustion of biofuel and high-energy waste. The dry combustible fraction of source-sorted household waste was mixed with the energy crop reed canary-grass (Phalaris Arundinacea L.), and combusted in both a 5-kW pilot scale reactor and a biofuel boiler with 140-180 kW output capacity, in the form of pellets and briquettes, respectively. The chlorine content of the waste fraction was 0.2%, most of which originated from plastics. The HCl emissions exceeded levels stipulated in new EU-directives, but levels of equal magnitude were also generated from combustion of the pure biofuel. Addition of waste to the biofuel did not give any apparent increase in emissions of organic compounds. Dioxin levels were close to stipulated limits. With further refinement of combustion equipment, small-scale co-combustion systems have the potential to comply with emission regulations.

Hedman, Bjoern [Chemistry Department, Environmental Chemistry, Umeaa University, SE-901 87 Umeaa (Sweden)]. E-mail: bjorn.hedman@chem.umu.se; Burvall, Jan [Unit for Biomass Technology and Chemistry, Swedish University of Agricultural Sciences, Box 4097, SE-904 03 Umeaa (Sweden); Nilsson, Calle [NBC Defence, NBC Analysis, The Swedish Defence Research Agency, SE-901 82 Umeaa (Sweden); Marklund, Stellan [Chemistry Department, Environmental Chemistry, Umeaa University, SE-901 87 Umeaa (Sweden)

2005-07-01

418

Biofuels from algae for sustainable development  

Microsoft Academic Search

Microalgae are photosynthetic microorganisms that can produce lipids, proteins and carbohydrates in large amounts over short periods of time. These products can be processed into both biofuels and useful chemicals. Two algae samples (Cladophora fracta and Chlorella protothecoid) were studied for biofuel production. Microalgae appear to be the only source of renewable biodiesel that is capable of meeting the global

M. Fatih Demirbas

2011-01-01

419

Biofuels from microalgae: Lipid extraction and methane production from the residual biomass in a biorefinery approach.  

PubMed

Renewable fuels and energy are of major concern worldwide and new raw materials and processes for its generation are being investigated. Among these raw materials, algae are a promising source of lipids and energy. Thus, in this work four different algae have been used for lipid extraction and biogas generation. Lipids were obtained by supercritical CO2 extraction (SCCO2), while anaerobic digestion of the lipid-exhausted algae biomass was used for biogas production. The extracted oil composition was analyzed (saturated, monounsaturated and polyunsaturated fatty acids) and quantified. The highest lipid yields were obtained from Tetraselmis sp. (11%) and Scenedesmus almeriensis (10%), while the highest methane production from the lipid-exhausted algae biomass corresponded to Tetraselmis sp. (236mLCH4/gVSadded). PMID:25151474

Hernndez, D; Solana, M; Riao, B; Garca-Gonzlez, M C; Bertucco, A

2014-10-01

420

Pretreatment of woody biomass for biofuel production: energy efficiency, technologies, and recalcitrance  

Microsoft Academic Search

This mini review discusses several key technical issues associated with cellulosic ethanol production from woody biomass:\\u000a energy consumption for woody biomass pretreatment, pretreatment energy efficiency, woody biomass pretreatment technologies,\\u000a and quantification of woody biomass recalcitrance. Both total sugar yield and pretreatment energy efficiency, defined as the\\u000a total sugar recovery divided by total energy consumption for pretreatment, should be used to

J. Y. Zhu; Xuejun Pan; Ronald S. Zalesny Jr

2010-01-01