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1

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

PubMed

The desire to reduce dependence on the ever diminishing fossil fuel reserves coupled with the impetus towards green energy has seen increased research in biofuels as alternative sources of energy. Lignocellulose materials are one of the most promising feedstocks for advanced biofuels production. However, their utilisation is dependent on the efficient hydrolysis of polysaccharides, which in part is dependent on cost-effective and benign pretreatment of biomass to remove or modify lignin and release or expose sugars to hydrolytic enzymes. Laccase is one of the enzymes that are being investigated not only for potential use as pretreatment agents in biofuel production, mainly as a delignifying enzyme, but also as a biotechnological tool for removal of inhibitors (mainly phenolic) of subsequent enzymatic processes. The current review discusses the major advances in the application of laccase as a potential pretreatment strategy, the underlying principles as well as directions for future research in the search for better enzyme-based technologies for biofuel production. Future perspectives could include synergy between enzymes that may be required for optimal results and the adoption of the biorefinery concept in line with the move towards the global implementation of the bioeconomy strategy. PMID:24841120

Kudanga, Tukayi; Le Roes-Hill, Marilize

2014-08-01

2

Microbiological aspects of biofuel production: Current status and future directions  

Microsoft Academic Search

Biofuel research is currently an area of immense interest due to the increase in global energy demand by emerging economies and the recent increases in global oil prices. Multiple approaches are currently being researched for the use of microorganisms in the production of various biofuel (e.g. alcohols, hydrogen, biodiesel, and biogas) from multiple starting materials. This review provides a brief

Mostafa S. Elshahed

2010-01-01

3

Present and potential future oilseed production systems for biofuels  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

4

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

USGS Publications Warehouse

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

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

2014-01-01

5

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

6

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

7

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.

8

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

9

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

10

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 worldâ??s 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

11

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

12

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...

13

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

14

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

15

ShapingTHE FUTURE Biofuels or food? Quest for land  

E-print Network

a crucial role in these priorities. On the Government's in- structions, the university is already working efforts to achieve sustainable European agriculture, with sound food products and healthy animals. We mustShapingTHE FUTURE Biofuels or food? Quest for land poses a threat to poor women in Africa. PAGE 4

16

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

17

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

18

Growing duckweed for biofuel production: a review.  

PubMed

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

Cui, W; Cheng, J J

2015-01-01

19

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

20

Supercritical fluids technology for clean biofuel production  

Microsoft Academic Search

Biofuels are liquid or gaseous fuels that are predominantly produced from biomass for transport sector applications. As biofuels are renewable, sustainable, carbon neutral and environmentally benign, they have been proposed as promising alternative fuels for gasoline and diesel engines. This paper reviews state-of-the-art application of the supercritical fluid (SCF) technique in biofuels production that includes biodiesel from vegetable oils via

Dongsheng Wen; H. Jiang; Kai Zhang

2009-01-01

21

Multiphase Flow Modeling of Biofuel Production Processes  

SciTech Connect

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

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

2011-06-01

22

Biofuels production and the environmental indicators  

Microsoft Academic Search

The paper evaluates the role of the bio-fuels production in the transportation sector in the world, for programs of greenhouse gases emissions reductions and sustainable environmental performance. Depending on the methodology used to account for the local pollutant emissions and the global greenhouse gases emissions during the production and consumption of both the fossil and bio-fuels, the results can show

Marcos Sebastião de Paula Gomes; Maria Silvia Muylaert de Araújo

2009-01-01

23

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

24

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

25

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

26

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

27

Effective Biofuel Production by an Intelligent Bioreactor  

Microsoft Academic Search

With the aim of contributing to efforts to solve global energy and environmental problems, a joint research project — Effective Biofuel Production by an Intelligent Bioreactor — has been set up with participants representing several universities, research institute, and industrial companies. Biofuel obtained from biomass resources is seen as an important source of ‘clean energy’ by virtue of features such

Hideki Fukuda; Akihiko Kondo; Hideo Noda

28

Modifying plants for biofuel and biomaterial production.  

PubMed

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

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

2014-12-01

29

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

30

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

31

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 worldâ??s 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

32

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

33

Future Testing Opportunities to Ensure Sustainability of the Biofuels Industry  

Microsoft Academic Search

For the soil and plant analysis community, development and expansion of biofuels will create many opportunities to provide a wide variety of analytical services. Our objective is to explore potential areas where those services could be marketed to support sustainable development of biofuels. One of the first is to provide soil fertility and plant nutrition information for sustainable feedstock production.

Douglas L. Karlen; Brian J. Kerr

2012-01-01

34

Developments and perspectives of photobioreactors for biofuel production  

Microsoft Academic Search

The production of biofuels from microalgae requires efficient photobioreactors in order to meet the tight constraints of energy\\u000a efficiency and economic profitability. Current cultivation systems are designed for high-value products rather than for mass\\u000a production of cheap energy carriers. Future bioreactors will imply innovative solutions in terms of energy efficiency, light\\u000a and gas transfer or attainable biomass concentration to lower

Michael Morweiser; Olaf Kruse; Ben Hankamer; Clemens Posten

2010-01-01

35

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

NASA Astrophysics Data System (ADS)

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

Ayers, Alex Elgin

36

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

37

Health impact assessment of liquid biofuel production.  

PubMed

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

Fink, Rok; Medved, Sašo

2013-01-01

38

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

39

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

40

Biofuels for the future Biocoal: Full steam ahead  

E-print Network

NRRI Now Biofuels for the future Biocoal: Full steam ahead 2nd chance for old growth wood Sediment, energy efficiency, manufacturing process efficiencies to reduce waste in all forms, especially pollution Facility. Our mission was to create a modern, sustainable manufacturing plant from an existing brownfield

Netoff, Theoden

41

Closed photo-bioreactors as tools for biofuel production.  

PubMed

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

Lehr, Florian; Posten, Clemens

2009-06-01

42

Dual role of microalgae: Phycoremediation of domestic wastewater and biomass production for sustainable biofuels production  

Microsoft Academic Search

Global threats of fuel shortages in the near future and climate change due to green-house gas emissions are posing serious challenges and hence and it is imperative to explore means for sustainable ways of averting the consequences. The dual application of microalgae for phycoremediation and biomass production for sustainable biofuels production is a feasible option. The use of high rate

I. Rawat; R. Ranjith Kumar; T. Mutanda; F. Bux

2011-01-01

43

Developments and perspectives of photobioreactors for biofuel production.  

PubMed

The production of biofuels from microalgae requires efficient photobioreactors in order to meet the tight constraints of energy efficiency and economic profitability. Current cultivation systems are designed for high-value products rather than for mass production of cheap energy carriers. Future bioreactors will imply innovative solutions in terms of energy efficiency, light and gas transfer or attainable biomass concentration to lower the energy demand and cut down production costs. A new generation of highly developed reactor designs demonstrates the enormous potential of photobioreactors. However, a net energy production with microalgae remains challenging. Therefore, it is essential to review all aspects and production steps for optimization potential. This includes a custom process design according to production organism, desired product and production site. Moreover, the potential of microalgae to synthesize valuable products additionally to the energetic use can be integrated into a production concept as well as waste streams for carbon supply or temperature control. PMID:20535467

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

2010-07-01

44

Spatial scale and social impacts of biofuel production  

Microsoft Academic Search

The prospect of biofuels going ‘mainstream’ has drawn more attention to the social impacts of the production and use of transport biofuels. Since 2007, many media stories have appeared about alleged negative impacts of biofuels, notably the price of food going up or land-grab by plantation developers. These stories stand in stark contrast with the rosy picture painted by some

Dan van der Horst; Saskia Vermeylen

2011-01-01

45

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

46

Plant biotechnology for lignocellulosic biofuel production.  

PubMed

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

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

2014-12-01

47

A Survey of Biofuel Production potentials in Russia  

NASA Astrophysics Data System (ADS)

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

Lykova, Natalya; Gustafsson, Jan-Erik

2010-01-01

48

Lipid-based biofuel production from wastewater.  

PubMed

Increasing world population, urbanization and industrialization are driving global increases in wastewater production. Wastewater comprises significant amounts of chemical energy primarily in the form of organic molecules (in particular lipids), which are currently not being recovered comprehensively. Within biological wastewater treatment (BWWT) systems, specialized microorganisms assimilate and store lipids anaerobically. These intracellular stores represent interesting feedstocks for biofuel synthesis. Here, we review our current understanding of the genetic and functional basis for bacterial lipid accumulation and processing, and relate this to lipid accumulating bacterial populations which occur naturally in BWWT plants. A grand challenge for microbial ecologists and engineers now lies in translating this knowledge into the design of new BWWT processes for the comprehensive recovery of lipids from wastewater streams and their subsequent conversion into biofuel. PMID:24768793

Muller, Emilie E L; Sheik, Abdul R; Wilmes, Paul

2014-12-01

49

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

50

Cyanobacteria as a Platform for Biofuel Production  

PubMed Central

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

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

2013-01-01

51

National microalgae biofuel production potential and resource demand  

Microsoft Academic Search

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

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

2011-01-01

52

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

53

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

54

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

55

United Nations Conference on Trade and Development Biofuel production technologies  

E-print Network

United Nations Conference on Trade and Development Biofuel production technologies: status.............................. 2 3. Global fuel ethanol production by country in 2006 of the activities of the UNCTAD Biofuels Initiative. The author expresses his thanks to Lucas Assunção, Simonetta

56

The Impacts of Biofuel Production on Food Prices: a review  

Microsoft Academic Search

The various calculations of the impacts of biofuel production on the mid-term projections of food and agricultural commodity prices are difficult to reconcile. This is largely due to the intricate set of assumptions, the differences in the baseline scenario and in the projection horizon they are built upon. For similar reasons, studies evaluating the impact of biofuel production on food

Nicolas Gerber; Manfred Van Eckert; Thomas Breuer

2008-01-01

57

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

58

Genetically Engineered Materials for Biofuels Production  

NASA Astrophysics Data System (ADS)

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

Raab, Michael

2012-02-01

59

Rapid saccharification for production of cellulosic biofuels.  

PubMed

The economical production of biofuels is hindered by the recalcitrance of lignocellulose to processing, causing high consumption of processing enzymes and impeding hydrolysis of pretreated lignocellulosic biomass. We determined the major rate-limiting factor in the hydrolysis of popping pre-treated rice straw (PPRS) by examining cellulase adsorption to lignin and cellulose, amorphogenesis of PPRS, and re-hydrolysis. Based on the results, equivalence between enzyme loading and the open structural area of cellulose was required to significantly increase productive adsorption of cellulase and to accelerate enzymatic saccharification of PPRS. Amorphogenesis of PPRS by phosphoric acid treatment to expand open structural area of the cellulose fibers resulted in twofold higher cellulase adsorption and increased the yield of the first re-hydrolysis step from 13% to 46%. The total yield from PPRS was increased to 84% after 3h. These results provide evidence that cellulose structure is one of major effects on the enzymatic hydrolysis. PMID:24607460

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

2014-04-01

60

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)...

61

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

Federal Register 2010, 2011, 2012, 2013, 2014

...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

62

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

63

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

64

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

Code of Federal Regulations, 2014 CFR

...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

65

Microbiology of synthesis gas fermentation for biofuel production.  

PubMed

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

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

2007-06-01

66

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

67

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

68

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

69

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

70

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

71

Downstream Processing of Synechocystis for Biofuel Production  

NASA Astrophysics Data System (ADS)

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

Sheng, Jie

72

Novel Australian biological resources for biofuel production  

Microsoft Academic Search

A major new research initiative is proposed to screen Australian flora (10%) of species globally for new species and traits for biofuels. Advances in biotechnology have provided genomics tools that will allow the screening of biodiversity for new biofuel genetic resources. The Australian plant DNA bank is collecting material for screening from the regions controlled by the 9 governments in

Robert J Henry; Stephen D Williams

2008-01-01

73

Sustainable production of grain crops for biofuels  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

74

High-biomass sorghums for biomass biofuel production  

E-print Network

High-biomass sorghums are being developed as a dedicated energy crop for biofuels. Their high biomass yields provide large quantities of structural carbohydrates (cellulose, lignin, etc.) for energy production. Sorghum improvement for applications...

Packer, Daniel

2011-05-09

75

Policy Options to Support Biofuel Production  

Microsoft Academic Search

Biofuels for use in the transportation sector have been produced on a significant scale since\\u000a the 1970s, using a variety of technologies. The biofuels widely available today are predominantly\\u000a sugar- and starch-based bioethanol, and oilseed- and waste oil-based biodiesel, although new technologies\\u000a under development may allow the use of lignocellulosic feedstocks. Measures to promote the use of biofuels\\u000a include renewable fuel mandates,

W. E. Mabee

76

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

77

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

78

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

PubMed

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

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

2014-06-01

79

Microbial engineering for the production of advanced biofuels.  

PubMed

Advanced biofuels produced by microorganisms have similar properties to petroleum-based fuels, and can 'drop in' to the existing transportation infrastructure. However, producing these biofuels in yields high enough to be useful requires the engineering of the microorganism's metabolism. Such engineering is not based on just one specific feedstock or host organism. Data-driven and synthetic-biology approaches can be used to optimize both the host and pathways to maximize fuel production. Despite some success, challenges still need to be met to move advanced biofuels towards commercialization, and to compete with more conventional fuels. PMID:22895337

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

2012-08-16

80

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

81

Tree legumes as feedstock for sustainable biofuel production: Opportunities and challenges.  

PubMed

Concerns about future fossil fuel supplies and the environmental effects of their consumption have prompted the search for alternative sources of liquid fuels, specifically biofuels. However, it is important that the sources of such biofuel have minimal impact on global food supplies, land use, and commodity prices. Many legume trees can be grown on so-called marginal land with beneficial effects to the environment through their symbiotic interaction with "Rhizobia" and the associated process of root nodule development and biological nitrogen fixation. Once established legume trees can live for many years and some produce an annual yield of oil-rich seeds. For example, the tropical and sub-tropical legume tree Pongamia pinnata produces large seeds (?1.5-2g) that contain about 40% oil, the quality and composition of which is regarded as highly desirable for sustainable biofuel production. Here we consider the benefits of legume trees as future energy crops, particularly in relation to their impact on nitrogen inputs and the net energy balance for biofuel production, and also ways in which these as yet fully domesticated species may be further improved for optimal use as biofuel feedstock. PMID:21715045

Biswas, Bandana; Scott, Paul T; Gresshoff, Peter M

2011-11-01

82

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

NASA Astrophysics Data System (ADS)

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

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

2010-12-01

83

Microalgae as Sustainable Renewable Energy Feedstock for Biofuel Production  

PubMed Central

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

Yusoff, Fatimah Md.; Shariff, M.

2015-01-01

84

Future testing opportunities to ensure sustainability of the biofuels industry  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

85

SESSION 2: ENERGY AND AGRICULTURE: THE FUTURE OF BIOFUELS  

Microsoft Academic Search

Biofuels are receiving increased attention worldwide. The International Energy Agency projects that global consumption of ethanol and biodiesel will increase nearly fivefold over the next two decades, accounting for four percent of global transportation fuels by 2030, up from one percent today (IEA, 2008). Growth is expected to be even more pronounced in Europe: biofuels consumption is expected to quadruple

MICHAEL A. LEVI

86

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

SciTech Connect

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

Wohlbach, Dana J.; Gasch, Audrey P.

2014-08-05

87

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

88

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

89

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

Microsoft Academic Search

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

Michael Wang; Hong Huo; Salil Arora

2011-01-01

90

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

Microsoft Academic Search

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

M. Wang; H. Huo; S. Arora

2011-01-01

91

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

PubMed

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

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

2014-03-18

92

The potential of C4 grasses for cellulosic biofuel production  

PubMed Central

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

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

2013-01-01

93

The potential of C4 grasses for cellulosic biofuel production.  

PubMed

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

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

2013-01-01

94

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

95

Limits to biofuels  

NASA Astrophysics Data System (ADS)

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

Johansson, S.

2013-06-01

96

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

97

Managing water resources for biomass production in a biofuel economy  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

98

Soil Quality as an Indicator of Sustainable Biofuel Feedstock Production  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

99

Trade-offs between agricultural production and biodiversity for biofuel production  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

100

Impact of biofuel production and other supply and demand factors on food price increases in 2008  

Microsoft Academic Search

The prices of some grain commodities more than doubled from March 2007 to March 2008. Increased food prices coincided with increasing global biofuel production, leading to speculation that biofuel production was responsible for the increased food prices. However, over the six-month period after March 2008, grain prices declined by 50% while biofuel production continued to increase. It is not possible

Sherry A. Mueller; James E. Anderson; Timothy J. Wallington

2011-01-01

101

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

102

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

E-print Network

1 Sub-national TIMES model for analyzing regional future use of Biomass and Biofuels in France Introduction Renewable energy sources such as biomass and biofuels are increasingly being seen as important of biofuels on the final consumption of energy in transport should be 10%. The long-term target is to reduce

Boyer, Edmond

103

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

104

Will Sulfur Limit Bio-fuel Corn Production?  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

105

Economic Policy and Resource Implications of Biofuel Feedstock Production  

E-print Network

used deleted from the total, the cost of producing a gallon of biomass ethanol is substantially higher than that of gasoline. The impacts of an exogenously-specified biofuel mandate fulfilled by the production of a dedicated biomass crop and its...

Adusumilli, Naveen

2012-10-19

106

Production of Liquid Biofuels from Biomass: Emerging Technologies  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

107

Biofuels production for smallholder producers in the Greater Mekong Subregion  

Microsoft Academic Search

Looming concerns on rising food prices and food security has slowed down the impetus in biofuel production. The development of the sub-sector, however, remains an important agenda among developing countries like those of the Greater Mekong Sub-region (GMS) that have abundant labour and natural resources but have limited supply of fossil fuels which continues to serve as a constraint to

Urooj S. Malik; Mahfuz Ahmed; Mercedita A. Sombilla; Sarah L. Cueno

2009-01-01

108

Spatially Explicit Life Cycle Assessment of Biofuel Feedstock Production  

EPA Science Inventory

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

109

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

110

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.

Dana Haine

111

Future Testing Opportunities to Ensure Sustainability of the Biofuels Industry  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

112

U.S. Renewable Fuel Standard 2: Impacts of Cellulosic Biofuel Production  

Microsoft Academic Search

Biofuels have been widely promoted as an important part of the global energy mix, due to public interest in alternative energy sourcing and a potential to reduce greenhouse gas emissions. Concurrently, questions have been raised about the social and environmental costs of biofuel production. While previous studies have focused primarily on biofuel production from conventional, starch-based feedstocks, this study provides

Jayson F. Beckman; Samuel Evans; Ronald D. Sands

2011-01-01

113

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.

114

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 wood—terpenes are the energy-dense fuel molecules that are the predominant components of turpentine. The team aims to increase the terpene storage potential and production capacity while improving the terpene composition to a point at which the trees could be tapped while alive, like sugar maples. Growth and production from these trees will take years, but this pioneering technology could have significant impact in making available an economical and domestic source of aviation and diesel biofuels.

None

2012-01-01

115

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 bacteria—increasing the organism’s access to its energy source and improving the efficiency of the biofuel-creation process. Finally, LBNL is tethering electrocatalysts to the bacteria’s surface which will further accelerate the rate at which the organism creates biofuel. LBNL is also developing a chemical method to transform the biofuel that the bacteria produce into ready-to-use jet fuel.

None

2010-08-01

116

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

117

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

118

Molecular Breeding of Advanced Microorganisms for Biofuel Production  

PubMed Central

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

Sakuragi, Hiroshi; Kuroda, Kouichi; Ueda, Mitsuyoshi

2011-01-01

119

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.

120

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

121

Global principles for sustainable biofuel production and trade  

Microsoft Academic Search

This article examines international attempts to regulate the production of and trade in biofuels by establishing criteria\\u000a and indicators and certification schemes. It focuses on the norms underlying the criteria and the community constructed on\\u000a the basis of them. The theoretical approach here rests on a discussion of these norms and on their constitutive role. This\\u000a role creates a community

Eero Palmujoki

2009-01-01

122

Development of an attached microalgal growth system for biofuel production  

Microsoft Academic Search

Algal biofuel production has gained a renewed interest in recent years but is still not economically feasible due to several\\u000a limitations related to algal culture. The objective of this study is to explore a novel attached culture system for growing\\u000a the alga Chlorella sp. as biodiesel feedstock, with dairy manure wastewater being used as growth medium. Among supporting materials tested

Michael B. Johnson; Zhiyou Wen

2010-01-01

123

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

124

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.

125

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

PubMed

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

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

2010-02-01

126

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

127

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

128

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

129

BIOFUEL AND BIOENERGY PRODUCTION FROM SUGAR BEETS  

EPA Science Inventory

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

130

The US Ethanol and Biofuels Boom: Its Origins, Current Status, and Future Prospects  

NSDL National Science Digital Library

This article explains why we are experiencing a boom in ethanol and other biofuels, the current status of biofuels, and prospects for the future under different policy regimes. I argue that today's boom is in a sense an unintended consequence of a fixed ethanol subsidy that was keyed to $20-per-barrel crude oil, combined with a surge in crude oil pricesinitially to $60 per barrel, and later doubling to $120 per barrel. Future prospects for corn ethanol depend on the crude oil price, the price of corn and distillers' grains, the market value of ethanol, plant capital and operating costs, and federal ethanol and biofuels policies. I examine the impacts of a wide range of policies for subsidies and renewable fuels standards. Policy choices will be absolutely critical in determining the extent to which biofuels targets are achieved and at what cost. However, if the price of oil remains above $100 per barrel, biofuels will continue to be produced even without government interventions.

Wallace E. Tyner (Purdue University; )

2008-08-01

131

Potential Enhancement of Biofuel Production Through Enzymatic Biomass Degradation Activity and Biodiesel Production by Halophilic Microorganisms  

Microsoft Academic Search

\\u000a There are many economic and negative environmental impacts that need to be solved before biofuels become a viable replacement\\u000a for some of the fossil fuel demand. One environmental problem is the great amount of water required for the production of\\u000a biofuels. The use of halophilic\\/halotolerant algae can greatly reduce the amount of water required for biodiesel production.\\u000a The use of

Matthew B. Begemann; Melanie R. Mormile; Varun G. Paul; Daniel J. Vidt

132

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

133

Tailoring lignin biosynthesis for efficient and sustainable biofuel production.  

PubMed

Increased global interest in a bio-based economy has reinvigorated the research on the cell wall structure and composition in plants. In particular, the study of plant lignification has become a central focus, with respect to its intractability and negative impact on the utilization of the cell wall biomass for producing biofuels and bio-based chemicals. Striking progress has been achieved in the last few years both on our fundamental understanding of lignin biosynthesis, deposition and assembly, and on the interplay of lignin synthesis with the plant growth and development. With the knowledge gleaned from basic studies, researchers are now able to invent and develop elegant biotechnological strategies to sophisticatedly manipulate the quantity and structure of lignin and thus to create economically viable bioenergy feedstocks. These concerted efforts open an avenue for the commercial production of cost-competitive biofuel to meet our energy needs. PMID:25209835

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

2014-12-01

134

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

E-print Network

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 consequences. In this paper, we argue that virtually all of these studies have overstated the impact of liquid biofuels on agricultural markets due to the fact that they have ignored the role of by-products resulting from the production of biofuels. Feed by-products of the biofuel industry, such as Dried Distillers Grains with Solubles (DDGS) and biodiesel by-products (BDBP) such as soy and rapeseed meals, can be used in the livestock industry as substitutes for grains and oilseed meals used in this industry. Hence, their presence mitigates the price impacts of biofuel production on the livestock and food industries. The importance of incorporating by-products of biofuel production in economic models is well recognized by some partial equilibrium analyses of biofuel production. However, to date, this issue has not been tackled by those conducting CGE analysis of biofuels programs. Accordingly,

2008-01-01

135

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

136

Alternatives to Trichoderma reesei in biofuel production.  

PubMed

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

Gusakov, Alexander V

2011-09-01

137

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, André M.; Skaggs, Richard J.; Huesemann, Michael H.; Lane, Leonard J.

2011-03-01

138

Downgrading recent estimates of land available for biofuel production.  

PubMed

Recent estimates of additional land available for bioenergy production range from 320 to 1411 million ha. These estimates were generated from four scenarios regarding the types of land suitable for bioenergy production using coarse-resolution inputs of soil productivity, slope, climate, and land cover. In this paper, these maps of land availability were assessed using high-resolution satellite imagery. Samples from these maps were selected and crowdsourcing of Google Earth images was used to determine the type of land cover and the degree of human impact. Based on this sample, a set of rules was formulated to downward adjust the original estimates for each of the four scenarios that were previously used to generate the maps of land availability for bioenergy production. The adjusted land availability estimates range from 56 to 1035 million ha depending upon the scenario and the ruleset used when the sample is corrected for bias. Large forest areas not intended for biofuel production purposes were present in all scenarios. However, these numbers should not be considered as definitive estimates but should be used to highlight the uncertainty in attempting to quantify land availability for biofuel production when using coarse-resolution inputs with implications for further policy development. PMID:23308357

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

2013-02-01

139

PETRO: Higher Productivity Crops for Biofuels  

SciTech Connect

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

None

2012-01-01

140

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

NASA Astrophysics Data System (ADS)

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

Gregg, J.; hvid, A.

2012-04-01

141

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

142

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

143

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

144

Microwave-assisted pyrolysis of biomass for liquid biofuels production.  

PubMed

Production of 2nd-generation biofuels from biomass residues and waste feedstock is gaining great concerns worldwide. Pyrolysis, a thermochemical conversion process involving rapid heating of feedstock under oxygen-absent condition to moderate temperature and rapid quenching of intermediate products, is an attractive way for bio-oil production. Various efforts have been made to improve pyrolysis process towards higher yield and quality of liquid biofuels and better energy efficiency. Microwave-assisted pyrolysis is one of the promising attempts, mainly due to efficient heating of feedstock by "microwave dielectric heating" effects. This paper presents a state-of-the-art review of microwave-assisted pyrolysis of biomass. First, conventional fast pyrolysis and microwave dielectric heating is briefly introduced. Then microwave-assisted pyrolysis process is thoroughly discussed stepwise from biomass pretreatment to bio-oil collection. The existing efforts are summarized in a table, providing a handy overview of the activities (e.g., feedstock and pretreatment, reactor/pyrolysis conditions) and findings (e.g., pyrolysis products) of various investigations. PMID:22771019

Yin, Chungen

2012-09-01

145

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

Microsoft Academic Search

This paper examines the competing claims on land use resulting from the expansion of biofuel production. Sugarcane for biofuel drives agrarian change in São Paulo state, which has become the major ethanol-producing region in Brazil. We analyse how the expansion of sugarcane-based ethanol in São Paulo state has impacted dairy and beef production. Historical changes in land use, production technologies,

A. L. Monteiro Novo; Kees Jansen; Maja Slingerland; Ken Giller

2010-01-01

146

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

147

Extremophiles in biofuel synthesis.  

PubMed

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

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

2010-01-01

148

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

149

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

150

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

151

Biofuels Bonanza?: Exploring community perceptions of the promises and perils of biofuels production  

Microsoft Academic Search

While the expansion of the biofuels industry has received scholarly attention with respect to environmental and food security concerns, little research has explored the impacts of biofuels industry on local communities where ethanol plants are located. Drawing on sociology of networks and flows theory to situate expansion of the industry globally, this paper uses a community case study approach to

Theresa Selfa; Laszlo Kulcsar; Carmen Bain; Richard Goe; Gerad Middendorf

2011-01-01

152

Tree legumes as feedstock for sustainable biofuel production: Opportunities and challenges  

Microsoft Academic Search

Concerns about future fossil fuel supplies and the environmental effects of their consumption have prompted the search for alternative sources of liquid fuels, specifically biofuels. However, it is important that the sources of such biofuel have minimal impact on global food supplies, land use, and commodity prices. Many legume trees can be grown on so-called marginal land with beneficial effects

Bandana Biswas; Paul T. Scott; Peter M. Gresshoff

2011-01-01

153

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.

154

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 (PFD’s) and piping and instrumentation diagrams (P&ID’s). This information can be used for the equipment layout and general arrangement drawings for the proposed process and eventual plant. An efficient bio-butanol pilot plant to convert ligno-cellulosic biomass feedstock from bagasse and wood chips will create significant number of green jobs for the Orangeburg, SC community that will be environmentally-friendly and generate much-needed income for farmers in the area.

Chowdhury, Kamal

2011-07-20

155

Biofuels production in developing countries: assessing tradeoffs in welfare and food security  

Microsoft Academic Search

In light of the recent rise in global food prices, much of the literature on crop-based biofuel production focuses on the potential impacts on food security. Studies have identified linkages between the usage of feedstocks in biofuel production and international food price increases. In addition, these studies indicate that food prices are expected to continue to rise over the next

Mandy Ewing; Siwa Msangi

2009-01-01

156

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

157

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

158

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

159

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

160

Innovative business models for sustainable biofuel production: the case of Tanzanian smallholder jatropha farmers in the global biofuel chain  

Microsoft Academic Search

This paper focuses on the smallholder outgrower model for jatropha biofuel cultivation in Tanzania. This model is based on seed production by small farmers who sell to a processing company that presses the bio-oil from the seeds locally, either for the local market or for export. This model has been implemented by a foreign investor in Tanzania, the social business

Annelies J. Balkema; Henny A. Romijn

2011-01-01

161

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

162

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

163

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

164

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

165

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 that both reduce oil dependency and reduce climate change. While algae fuels will minimize land use

166

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

Microsoft Academic Search

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

Watcharapol Pumkaew

2010-01-01

167

Biofuels and their by-products: Global economic and environmental implications  

Microsoft Academic Search

Recently a number of papers have used general equilibrium models to study the economy-wide and environmental consequences of the first generation of biofuels (FGB). In this paper, we argue that nearly all of these studies have overstated the impacts of FGB on global agricultural and land markets due to the fact that they have ignored the role of biofuel by-products.

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

2010-01-01

168

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

169

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

170

Effects of US biofuel policies on US and world petroleum product markets with consequences for greenhouse gas emissions  

Microsoft Academic Search

US biofuel policy includes greenhouse gas reduction targets. Regulators do not address the potential that biofuel policy can have indirect impacts on greenhouse gases through its impacts on petroleum product markets, and scientific research only partially addresses this question. We use economic models of US biofuel and agricultural markets and US and world petroleum and petroleum product markets to show

Wyatt Thompson; Jarrett Whistance; Seth Meyer

2011-01-01

171

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...

172

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

173

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

174

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

175

Can large-scale biofuels production be sustainable by 2020?  

Microsoft Academic Search

Worldwide, many nations impose blending of their transport fuels with biofuels, approximating 10% globally by 2020, to contribute to energy security while reducing emission of green house gasses (GHG). Food riots, scientific insights that question the GHG benefits and raised concern about the loss of biodiversity, have lead to the formulation by various governments of sustainability criteria for biofuels to

Prem S. Bindraban; Erwin H. Bulte; Sjaak G. Conijn

2009-01-01

176

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

177

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

PubMed Central

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

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

2014-01-01

178

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

179

Biofuel, dairy production and beef in Brazil: competing claims on land use in São 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, André Luiz Monteiro; Jansen, Kees; Slingerland, Maja; Giller, Ken

2010-01-01

180

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

181

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

182

Protein engineering in designing tailored enzymes and microorganisms for biofuels production  

PubMed Central

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

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

2009-01-01

183

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

184

at Western University From the production of biofuels, fuel cells and alternative forms of energy,  

E-print Network

at Western University From the production of biofuels, fuel cells and alternative forms of energy tailored nanotube- based materials for applications in such areas as fuel cells, batteries and sensing

Denham, Graham

185

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

186

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 ...

187

The economic prospects of cellulosic biomass for biofuel production  

NASA Astrophysics Data System (ADS)

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

Kumarappan, Subbu

188

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

PubMed

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

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

2015-01-01

189

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

PubMed

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

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

2015-05-01

190

The Implications of Biofuel Production on Soil Productivity  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

191

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 MIT’s biofuel-production system.

None

2010-07-15

192

[FeFe]-Hydrogenase-Catalyzed H2 Production in a Photoelectrochemical Biofuel Cell  

SciTech Connect

The Clostridium acetobutylicum [FeFe]-hydrogenase HydA has been investigated as a hydrogen production catalyst in a photoelectrochemical biofuel cell. Hydrogenase was adsorbed to pyrolytic graphite edge and carbon felt electrodes. Cyclic voltammograms of the immobilized hydrogenase films reveal cathodic proton reduction and anodic hydrogen oxidation, with a catalytic bias toward hydrogen evolution. When corrected for the electrochemically active surface area, the cathodic current densities are similar for both carbon electrodes, and 40% of those obtained with a platinum electrode. The high surface area carbon felt/hydrogenase electrode was subsequently used as the cathode in a photoelectrochemical biofuel cell. Under illumination, this device is able to oxidize a biofuel substrate and reduce protons to hydrogen. Similar photocurrents and hydrogen production rates were observed in the photoelectrochemical biofuel cell using either hydrogenase or platinum cathodes.

Hambourger, M.; Gervaldo, M.; Svedruzic, D.; King, P. W.; Gust, D.; Ghirardi, M.; Moore, A. L.; Moore, T. A.

2008-01-01

193

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

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

2012-01-01

194

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

Microsoft Academic Search

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

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

2011-01-01

195

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

196

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

197

Biofuels and biodiversity.  

PubMed

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

Wiens, John; Fargione, Joseph; Hill, Jason

2011-06-01

198

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

199

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

200

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

201

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

202

BIOWINOL TECHNOLOGIES: A HYBRID GREEN PROCESS FOR BIOFUEL PRODUCTION  

EPA Science Inventory

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

203

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

204

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

205

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 heating—the same process used to render wood into charcoal, caramelize sugar, and dry roast coffee and beans. RTI’s catalytic biomass pyrolysis differs from conventional flash pyrolysis in that its end product contains less oxygen, metals, and nitrogen—all of which contribute to corrosion, instability, and inefficiency in the fuel-production process. This technology is expected to easily integrate into the existing domestic petroleum refining infrastructure, making it an economically attractive option for biofuels production.

None

2010-01-01

206

Carbon Calculator for Land Use Change from Biofuels Production (CCLUB). Users' manual and technical documentation  

Microsoft Academic Search

The Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) calculates carbon emissions from land use change (LUC) for four different ethanol production pathways including corn grain ethanol and cellulosic ethanol from corn stover, miscanthus, and switchgrass. This document discusses the version of CCLUB released May 31, 2012 which includes corn, as did the previous CCLUB version, and three

S Mueller; JB Dunn; M Wang

2012-01-01

207

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

208

Integrated Assessment of Large-Scale Biofuel Production  

Microsoft Academic Search

This paper proposes a different framework for discussing the possibility of replacing a significant fraction of fossil energy consumption of modern economies with biofuels. The proposed analysis is not based on the two classic feasibility checks—land availability and output\\/input energy ratio—debated in the majority of the literature in this field. Rather, the focus is on the desirability of an energy

Mario Giampietro; Sergio Ulgiati

2005-01-01

209

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

210

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 450°C, 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

211

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

PubMed Central

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

212

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; Lee, Taek Soon; Thelen, Michael P

2014-01-01

213

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

214

Incentives for co-firing in bio-fuelled industrial steam, heat and power production—Swedish experiences  

Microsoft Academic Search

Various combinations of co-firing of biofuels and fossil fuels can be used as an efficient method to rapidly introduce biofuels into existing energy systems. They also offer effective utilisation of local, small fuel resources, used mainly by larger plants. This study analyses different factors and incentives that influence co-firing in bio-fuelled industrial production of steam, heat and power and case

B Hillring

2003-01-01

215

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

216

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

217

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

218

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

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

219

The current potential of algae biofuels in the United Arab Emirates  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

220

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

221

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

222

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

E-print Network

be cultivated in the United States, algae consume CO2 during photosynthesis (ideally resulting in a carbon This review paper describes systems used to cultivate microalgae for biofuel production. It addresses general, with an emphasis on large-scale reactors. Important design aspects include lighting, mixing, water consumption, CO2

Eldridge, R. Bruce

223

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

224

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

225

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

226

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

Technology Transfer Automated Retrieval System (TEKTRAN)

For secure and sustainable bioenergy and biofuel production to become a reality by the middle of the 21st century, building on the current infrastructure and existing technology is essential. However, at the same time, we must make substantial improvements and/or changes in the feedstocks used, the ...

227

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

E-print Network

Impacts of land use change due to biofuel crops on carbon balance, bioenergy production, West Lafayette, IN, 47907-2051, USA, Department of Agronomy, Purdue University, West Lafayette, IN, 47907, USA Abstract Growing concerns about energy and the environment have led to worldwide use

Zhuang, Qianlai

228

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) and the Center for Energy and Environmental Policy Research (CEEPR). These two centers bridge many key areas 77 Massachusetts Avenue MIT E19-411 Cambridge MA 02139-4307 (USA) Location: 400 Main Street

229

Establishment of perennial grass species for cellulosic biofuel production in Georgia  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

230

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

231

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

232

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

233

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

234

Scope of Algae as Third Generation Biofuels  

PubMed Central

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

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

2015-01-01

235

Evaluation of technological alternatives for process integration of sugarcane bagasse for sustainable biofuels production—Part 1  

Microsoft Academic Search

Nowadays, there is a tremendous global interest in the biofuels production. However, first generation biofuels have been debated about that energy-crop compete with food crops and thus cause food deficiency and price increases. In this sense, researchers have started looking for potential feedstock for ethanol such as lignocellulosic biomass (e.g., sugarcane bagasse), which does not affect food security. In this

K. Ojeda; O. Ávila; J. Suárez; V. Kafarov

2011-01-01

236

INCREASED BIOFUEL PRODUCTION IN THE COMING DECADE: TO WHAT EXTENT WILL IT AFFECT GLOBAL FRESHWATER RESOURCES?y  

Microsoft Academic Search

Irrigated agriculture accounts for 70% of global water withdrawals and therefore contributes substantially to global water scarcity. This article focuses on the impact of the increasing demand for biofuel on global water resources in the coming decade. Based on biofuel production projections for 2008 and 2017, it was estimated that currently around 1% of all water withdrawn for irrigation is

JIPPE HOOGEVEEN; JEAN-MARC FAURES; NICK VAN DE GIESSEN

237

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

238

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

239

Improving Efficiency of Cellulosic Fermentation via Genetic Engineering to Create “Smart Plants” for Biofuel Production  

Microsoft Academic Search

\\u000a Biomass-based fuel is a near-term alternative to petroleum for powering the global economy in an ecologically sustainable\\u000a fashion while minimizing the carbon footprint by decreasing net greenhouse gas emission. To affect this major shift in energy\\u000a use and fuel source in the near future, dramatic improvement in the efficiency of converting cellulose into biofuels will\\u000a be a key step. Optimization

Zeyu Xin; Naohide Watanabe; Eric Lam

240

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

PubMed

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

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

2011-01-01

241

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

PubMed

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

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

2012-09-01

242

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

243

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

244

Chromatin landscaping in algae reveals novel regulation pathway for biofuels production  

SciTech Connect

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

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

2013-02-19

245

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

246

Pongamia pinnata : An Untapped Resource for the Biofuels Industry of the Future  

Microsoft Academic Search

Pongamia pinnata (L.) Pierre is a fast-growing leguminous tree with the potential for high oil seed production and the added benefit of the\\u000a ability to grow on marginal land. These properties support the suitability of this plant for large-scale vegetable oil production\\u000a required by a sustainable biodiesel industry. The future success of P. pinnata as a sustainable source of feedstock

Paul T. Scott; Lisette Pregelj; Ning Chen; Johanna S. Hadler; Michael A. Djordjevic; Peter M. Gresshoff

2008-01-01

247

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

248

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

PubMed

The integration of microalgae-based biofuel and bioproducts production with wastewater treatment has major advantages for both industries. However, major challenges to the implementation of an integrated system include the large-scale production of algae and the harvesting of microalgae in a way that allows for downstream processing to produce biofuels and other bioproducts of value. Although the majority of algal production systems use suspended cultures in either open ponds or closed reactors, the use of attached cultures may offer several advantages. With regard to harvesting methods, better understanding and control of autoflocculation and bioflocculation could improve performance and reduce chemical addition requirements for conventional mechanical methods that include centrifugation, tangential filtration, gravity sedimentation, and dissolved air flotation. There are many approaches currently used by companies and industries using clean water at laboratory, bench, and pilot scale; however, large-scale systems for controlled algae production and/or harvesting for wastewater treatment and subsequent processing for bioproducts are lacking. Further investigation and development of large-scale production and harvesting methods for biofuels and bioproducts are necessary, particularly with less studied but promising approaches such as those involving attached algal biofilm cultures. PMID:21664266

Christenson, Logan; Sims, Ronald

2011-01-01

249

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

PubMed

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

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

2015-01-01

250

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

251

Predicting potential global distributions of two Miscanthus grasses: implications for horticulture, biofuel production, and biological invasions.  

PubMed

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

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

2014-01-01

252

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

PubMed Central

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

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

2014-01-01

253

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, João C.; Mukhopadhyay, Biswarup; Tyler, Brett M.

2014-01-01

254

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

255

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

256

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

257

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

PubMed

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

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

2012-04-01

258

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

PubMed

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

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

2012-11-16

259

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

260

Biotechnological improvement of lignocellulosic feedstock for enhanced biofuel productivity and processing  

Microsoft Academic Search

Secondary walls have recently drawn research interest as a primary source of sugars for liquid biofuel production. Secondary\\u000a walls are composed of a complex mixture of the structural polymers cellulose, hemicellulose, and lignin. A matrix of hemicellulose\\u000a and lignin surrounds the cellulose component of the plant’s cell wall in order to protect the cell from enzymatic attacks.\\u000a Such resistance, along

Jae-Heung Ko; Hyun-Tae Kim; Kyung-Hwan Han

2011-01-01

261

Participatory emergy synthesis of integrated food and biofuel production: a case study from Brazil  

Microsoft Academic Search

Large-scale production of biofuels is increasingly touted in national policies and international trade agreements. This global\\u000a trend is particularly clear in Brazil. However, the sugarcane monocultures promoted in the country depend on a range of fossil\\u000a fuel derivates, industrial inputs, chemical fertilizers, agrochemicals, machinery, labor exploitation and various other non-renewable\\u000a resources, making it a questionable alternative to substitute fossil energy

Daniel A. BergquistOtavio; Otávio Cavalett; Torbjörn Rydberg

2012-01-01

262

Impact of Biofuel Production on World Agricultural Markets: A Computable General Equilibrium Analysis  

Microsoft Academic Search

This paper introduces biofuels sectors as energy inputs into the GTAP Data Base and to the production and consumption structures of the GTAP-Energy model developed by Burniaux and Truong (2002), and further modified by McDougall and Golub (2008). We also incorporate Agro-ecological Zones (AEZs) for each of the land using sectors in line with Lee et al. (2005). The GTAP-E

Dileep Birur; Thomas Hertel; Wally Tyner

2008-01-01

263

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

264

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

NASA Astrophysics Data System (ADS)

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

Christiansen, Katrina Lea

2011-12-01

265

Importance of systems biology in engineering microbes for biofuel production  

SciTech Connect

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

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

2009-12-02

266

Impact of biofuel crop production on the formation of hypoxia in the Gulf of Mexico.  

PubMed

Many studies have compared corn-based ethanol to cellulosic ethanol on a per unit basis and have generally concluded that cellulosic ethanol will result in fewer environmental consequences, including nitrate (NO3(-)) output. This study takes a system-wide approach in considering the NO3(-) output and the relative areal extent of hypoxia in the Northern Gulf of Mexico (NGOM) due to the introduction of additional crops for biofuel production. We stochastically estimate NO3(-) loading to the NGOM and use these results to approximate the areal extent of hypoxia for scenarios that meet the Energy Independence and Security Act of 2007's biofuel goals for 2015 and 2022. Crops for ethanol include corn, corn stover, and switchgrass; all biodiesel is assumed to be from soybeans. Our results indicate that moving from corn to cellulosics for ethanol production may result in a 20-percent decrease (based on mean values) in NO3(-) output from the Mississippi and Atchafalaya River Basin (MARB). This decrease will not meet the EPA target for hypoxic zone reduction. An aggressive nutrient management strategy will be needed to reach the 5000 km2 areal extent of hypoxia in the NGOM goal set forth by the Mississippi River/Gulf of Mexico Watershed Nutrient Task Force even in the absence of biofuels, given current production to meet food, feed, and other industrial needs. PMID:19921924

Costello, Christine; Griffin, W Michael; Landis, Amy E; Matthews, H Scott

2009-10-15

267

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

PubMed

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

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

2013-12-01

268

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

269

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

270

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

E-print Network

through which a global biofuels market is being created. In this contribution, I propose a solution&FE, and intended to be the first step towards creating a global trading market for ethanol. It comes in the wake for reliability of trading and the growth of a global market. Secondly, it acts as a template for certification

271

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

272

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

273

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

274

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

275

Hybrid life-cycle assessment of algal biofuel production.  

PubMed

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

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

2015-05-01

276

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

PubMed

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

Christenson, Logan B; Sims, Ronald C

2012-07-01

277

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

278

Biofuels adoption in Nigeria : A preliminary review of feedstock and fuel production potentials  

Microsoft Academic Search

Purpose – The purpose of this paper is to make a preliminary analysis of the potentials for the adoption of biofuels in Nigeria. This initial analysis aims to capture some of the possibilities in the adoption of biofuel and the promotion of the cultivation of energy crops and processing of biofuels in Nigeria. Taking a step towards biofuel adoption is

Nelson Abila

2010-01-01

279

De Novo Transcriptomic Analysis of an Oleaginous Microalga: Pathway Description and Gene Discovery for Production of Next-Generation Biofuels  

Microsoft Academic Search

BackgroundEustigmatos cf. polyphem is a yellow-green unicellular soil microalga belonging to the eustimatophyte with high biomass and considerable production of triacylglycerols (TAGs) for biofuels, which is thus referred to as an oleaginous microalga. The paucity of microalgae genome sequences, however, limits development of gene-based biofuel feedstock optimization studies. Here we describe the sequencing and de novo transcriptome assembly for a

LingLin Wan; Juan Han; Min Sang; AiFen Li; Hong Wu; ShunJi Yin; ChengWu Zhang

2012-01-01

280

Improving Biocatalysts for the Production of Biofuels from Lignocellulosic Feedstocks  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

281

Perennial plants for biofuel production: Bridging genomics and field research.  

PubMed

Genomics provides the opportunity to explore the relationships of genes and phenotypes: its operational use in the context of breeding programs through strategies such as genomic selection, promises to foster the development of perennial crops dedicated to biodiesel production by increasing the efficiency of breeding programs and by shortening the length of the breeding cycles. PMID:25382800

Alves, Alexandre Alonso; Laviola, Bruno G; Formighieri, Eduardo F; Carels, Nicolas

2015-04-01

282

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

283

Can Sweet Sorghum be used for Biofuel Production?  

Technology Transfer Automated Retrieval System (TEKTRAN)

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

284

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

285

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

286

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

287

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 450 ppm 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

288

CO{sub 2} capture and biofuels production with microalgae  

SciTech Connect

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

Benemann, J.R. [Univ. of California, Berkeley, CA (United States)

1995-11-01

289

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

290

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

291

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

292

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

293

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

PubMed

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

Blaas, Harry; Kroeze, Carolien

2014-10-15

294

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

295

Security of feedstocks supply for future bio-ethanol production in Thailand  

Microsoft Academic Search

This study assesses the security of feedstock supply to satisfy the increased demand for bio-ethanol production based on the recent 15 years biofuels development plan and target (year 2008–2022) of the Thai government. Future bio-ethanol systems are modeled and the feedstock supply potentials analyzed based on three scenarios including low-, moderate- and high-yields improvement. The three scenarios are modeled and

Thapat Silalertruksa; Shabbir H. Gheewala

2010-01-01

296

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.

297

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

SciTech Connect

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

Bai, Xuemei [Cellana LLC; Sabarsky, Martin

2013-09-30

298

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

SciTech Connect

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

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

2014-06-19

299

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

300

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 (4.7–70.6%) in sediment yield due to erosion and a slight decrease (1.2–3.2%) in water yield were estimated with the stover removal rate ranging between 40% and 100%, the nitrate nitrogen load declined about 6–10.1%. In comparison to growing corn, growing either switchgrass or miscanthus can reduce sediment erosion greatly. However, land cover changes from native grass to switchgrass or miscanthus would lead to a decrease in water yield and an increase in nitrate nitrogen load. In contrast to growing switchgrass, growing miscanthus is more productive in generating biomass, but its higher water demand may reduce water availability in the study area.

Wu, Y.; Liu, S.

2012-01-01

301

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

DOE Data Explorer

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

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

302

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

303

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

304

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

305

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

306

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

307

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

308

[Life cycle assessment on oxygen biofuels].  

PubMed

Life Cycle Assessment (LCA) was used to compare energy consumption and pollutant emissions of two oxygen biofuels, ethanol and methyl ester, which were mixed with gasoline and diesel oil at levels of 10% and 30% of the biofuel. The future of oxygen-containing biofuels was analyzed and forecasted. The results show that the mixture of biofuels and petroleum products can reduce crude oil consumption, but only methyl ester alternative fuel can reduce fossil fuel consumption. Use of methyl ester mixtures would reduce NOx by 50% compared to gasoline or diesel on a life cycle basis; however, NOx would increase using ethanol. Each alternative fuel mixture reduced PM10 emissions from the vehicle and methyl ester decreased VOCs. The SO2 emissions from the fuel production processes, which account for about 80% of SO2 life cycle emissions, must be strictly controlled. PMID:16447424

Yi, Hong-hong; Zhu, Yong-qing; Wang, Jian-xin; Hao, Ji-ming

2005-11-01

309

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 mV cm-2-electrode and 1.41 µA cm-2-electrode electricity were produced and 21 mM acetate was consumed. With the modified electrode with Neutral Red, 3.12 mV cm-2-electrode and 3.1 µA cm-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

310

Versatile microbial surface-display for environmental remediation and biofuels production  

SciTech Connect

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

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

2008-02-14

311

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

SciTech Connect

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

None

2010-07-16

312

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

313

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

314

Engineering Terpene Biosynthesis in Streptomyces for Production of the Advanced Biofuel Precursor Bisabolene.  

PubMed

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

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

2014-07-01

315

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

PubMed Central

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

316

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

PubMed

This research focuses on investigating the use of common biofuel grasses to assess their potential as agents of long-term remediation of contaminated soils using lead as a model heavy metal ion. We present evidence demonstrating that switch grass and Timothy grass may be potentially useful for long-term phytoremediation of heavy metal contaminated soils and describe novel techniques to track and remove contaminants from inception to useful product. Enzymatic digestion and thermochemical approaches are being used to convert this lignocellulosic feedstock into useful product (sugars, ethanol, biocrude oil + biochar). Preliminary studies on enzymatic hydrolysis and fast pyrolysis of the Switchgrass materials that were grown in heavy metal contaminated soil and non-contaminated soils show that the presence of lead in the Switchgrass material feedstock does not adversely affect the outcomes of the conversion processes. These results indicate that the modest levels of contaminant uptake allow these grass species to serve as phytoremediation agents as well as feedstocks for biofuel production in areas degraded by industrial pollution. PMID:25495935

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

2015-01-01

317

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

318

Biofuel Co-products as Swine Feed Ingredients: Combining Distillers Dried Grains with Solubles (DDGS) and Crude Glycerin  

Technology Transfer Automated Retrieval System (TEKTRAN)

Production of biofuels is increasing both the demand for traditional energy feedstuffs for pigs and the availability of co-products, particularly distillers dried grains with solubles (DDGS) and crude glycerin. Oil naturally found in corn grain is concentrated in DDGS generated from ethanol producti...

319

Land use competition for production of food and liquid biofuels: An analysis of the arguments in the current debate  

Microsoft Academic Search

This article analyses the current state of the debate over competition for land use, by means of an index of the main arguments in favor and against the production of liquid biofuels and the impacts on food production. Based on this index, an analytic framework is constructed to establish the causal relations indicated by the existing studies on this competition.

Régis Rathmann; Alexandre Szklo; Roberto Schaeffer

2010-01-01

320

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

321

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

322

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

323

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 (2.1±0.3 mm/yr) in 24% of stations, increases in baseflow (0.7±0.3 mm/yr) in 60% of stations, and in baseflow index (0.2±0.1%/yr) in 44% of stations. Although climate variability and land surface changes contributed equally to streamflow changes, land surface changes contributed about three times more than climate variability to baseflow and seven times more to baseflow index. Watersheds (~50%) with no significant climate change but with significant flow change provide direct evidence that land surface changes in the Midwest, including crop types, tillage, tiling etc, produced significant impacts on hydrologic processes. Limiting analysis to these watersheds shows that ratios of land surface changes to climate variability was a factor of three for streamflow, 4.6 for baseflow, and 13.5 for baseflow index. These changes in flow have generally been accompanied by degradation of water quality. Because past changes in crop types have been dominated by perennial crops to annual (corn and soybeans) crops, reversal to more perennial grasses for second generation biofuels should reduce flow, particularly baseflow in the future, with consequent improvements in water quality.

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

2012-12-01

324

Comparative genomics of xylose-fermenting fungi for enhanced biofuel production  

SciTech Connect

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

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

2011-02-24

325

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

326

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 biofuels—methanol, ethanol, hydrogen, and synthetic diesel—is 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

327

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

328

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

329

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

PubMed

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

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

2015-05-01

330

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. PMID:25225637

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

2014-01-01

331

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

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

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

2011-12-01

332

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 world’s largest freshwater resource, the Laurentian Great Lakes (GL). To understand the linkages between land use and P delivery, we coupled two spatially explicit models, the landscape-scale SPARROW P fate and transport watershed model and the Land Transformation Model (LTM) land use change model, to predict future P export from nonpoint and point sources caused by changes in land use. According to LTM predictions over the period 2010–2040, the GL region of the U.S. may experience a doubling of urbanized areas and agricultural areas may increase by 10%, due to biofuel feedstock cultivation. These land use changes are predicted to increase P loadings from the U.S. side of the GL basin by 3.5–9.5%, depending on the Lake watershed and development scenario. The exception is Lake Ontario, where loading is predicted to decrease by 1.8% for one scenario, due to population losses in the drainage area. Overall, urban expansion is estimated to increase P loadings by 3.4%. Agricultural expansion associated with predicted biofuel feedstock cultivation is predicted to increase P loadings by an additional 2.4%. Watersheds that export P most 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

333

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

334

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...

335

Relative importance of climate and land surface changes on hydrologic changes in the US Midwest since the 1930s: Implications for biofuel production  

NASA Astrophysics Data System (ADS)

The US Midwest is an important area of first generation biofuels, accounting for 80-90% of US corn and soybean production (2009-2011). However, there are potential adverse impacts of biofuel production on water resources in this area. The objective of this study was to assess potential impacts of biofuel production on water resources by exploring relationships between hydrologic changes and climate and land surface changes based on long-term (˜1930s-2010) stream gage and climate data from 55 unregulated watersheds in the US Midwest. Long-term trends in climate (precipitation and potential evapotranspiration) and flow were evaluated. Sensitivity of changes in annual streamflow and baseflow to climate was evaluated using climate elasticity (sensitivity) and the residuals were attributed to land surface changes. Results show that streamflow increased significantly (p < 0.05) in 35% (19/55) of watersheds (median 2.4 ± 0.3 mm/year), baseflow increased in 58% of watersheds (median 1.1 ± 0.4 mm/year), and baseflow index (baseflow/streamflow, BFI) increased in 42% of watersheds (median 0.2 ± 0.1%/year). Overall, climatic variability contributed more than land surface change to streamflow change (61 ± 19% vs. 40 ± 18%), while land surface change contributed much more to baseflow (74 ± 10% vs. 27 ± 10%; 2.7 times higher) and to BFI (119 ± 14% vs. 27 ± 18%; 4.4 times higher) than climate change. Watersheds (25/55, 45%) with no significant trend in climate but with significant flow trends provide direct evidence that the Midwest land surface change (cropping system and related land management) significantly impacted flow processes. Restricting analysis to these watersheds shows that land surface change contributed 2.0 times more than climate variability/change to streamflow change, 3.2 times more to baseflow change, and 7.7 times more to BFI change. The importance of past land surface changes on hydrology suggests that any future land surface changes, such as biofuel expansion or changing biofuel feedstocks, should consider impacts on the hydrology.

Xu, Xianli; Scanlon, Bridget R.; Schilling, Keith; Sun, Alex

2013-08-01

336

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

NASA Astrophysics Data System (ADS)

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

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

2012-12-01

337

Mitigation: A sweetener for biofuels  

NASA Astrophysics Data System (ADS)

The climate impact of biofuels is usually considered in terms of their net effect on greenhouse-gas emissions. The expansion of sugar cane into pastureland for biofuel production is now shown to also exert a direct local cooling effect.

Betts, Richard A.

2011-05-01

338

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

339

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

340

Space for innovation for sustainable community-based biofuel production and use: Lessons learned for policy from Nhambita community, Mozambique  

Microsoft Academic Search

This paper provides insights and recommendations for policy on the opportunities and constrains that influence the space for innovation for sustainable community-based biofuel production and use. Promoted by the Mozambican government, Nhambita community established jatropha trials in 2005. Initial results were promising, but crop failure and the absence of organized markets led to scepticism amongst farmers.We start from the idea

Marc Schut; Annemarie van Paassen; Cees Leeuwis; Sandra Bos; Wilson Leonardo; Anna Lerner

2011-01-01

341

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

342

Development of optimal enzymatic and microbial conversion systems for biofuel production  

NASA Astrophysics Data System (ADS)

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

Aramrueang, Natthiporn

343

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

344

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

PubMed

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

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

2014-01-01

345

The role of symbiotic nitrogen fixation in sustainable production of biofuels.  

PubMed

With the ever-increasing population of the world (expected to reach 9.6 billion by 2050), and altered life style, comes an increased demand for food, fuel and fiber. However, scarcity of land, water and energy accompanied by climate change means that to produce enough to meet the demands is getting increasingly challenging. Today we must use every avenue from science and technology available to address these challenges. The natural process of symbiotic nitrogen fixation, whereby plants such as legumes fix atmospheric nitrogen gas to ammonia, usable by plants can have a substantial impact as it is found in nature, has low environmental and economic costs and is broadly established. Here we look at the importance of symbiotic nitrogen fixation in the production of biofuel feedstocks; how this process can address major challenges, how improving nitrogen fixation is essential, and what we can do about it. PMID:24786096

Biswas, Bandana; Gresshoff, Peter M

2014-01-01

346

The Role of Symbiotic Nitrogen Fixation in Sustainable Production of Biofuels  

PubMed Central

With the ever-increasing population of the world (expected to reach 9.6 billion by 2050), and altered life style, comes an increased demand for food, fuel and fiber. However, scarcity of land, water and energy accompanied by climate change means that to produce enough to meet the demands is getting increasingly challenging. Today we must use every avenue from science and technology available to address these challenges. The natural process of symbiotic nitrogen fixation, whereby plants such as legumes fix atmospheric nitrogen gas to ammonia, usable by plants can have a substantial impact as it is found in nature, has low environmental and economic costs and is broadly established. Here we look at the importance of symbiotic nitrogen fixation in the production of biofuel feedstocks; how this process can address major challenges, how improving nitrogen fixation is essential, and what we can do about it. PMID:24786096

Biswas, Bandana; Gresshoff, Peter M.

2014-01-01

347

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

348

Environmental Assessment of Wood-Based Biofuel Production and Consumption Scenarios in Norway  

Microsoft Academic Search

SummaryIn Norway, the boreal forest offers a considerable resource base, and emerging technologies may soon make it commercially viable to convert these resources into low-carbon biofuels. Decision makers are required to make informed decisions about the environmental implications of wood biofuels today that will affect the medium- and long-term development of a wood-based biofuels industry in Norway. We first assess

Ryan M. Bright; Anders Hammer Strømman; Troy R. Hawkins

2010-01-01

349

Recent advances on the production and utilization trends of bio-fuels: A global perspective  

Microsoft Academic Search

Bio-fuels are important because they replace petroleum fuels. There are many benefits for the environment, economy and consumers in using bio-fuels. Bio-oil can be used as a substitute for fossil fuels to generate heat, power and\\/or chemicals. Upgrading of bio-oil to a transportation fuel is technically feasible, but needs further development. Bio-fuels are made from biomass through thermochemical processes such

M. F. Demirbas; Mustafa Balat

2006-01-01

350

Production of biofuels and biochemicals by in vitro synthetic biosystems: Opportunities and challenges.  

PubMed

The largest obstacle to the cost-competitive production of low-value and high-impact biofuels and biochemicals (called biocommodities) is high production costs catalyzed by microbes due to their inherent weaknesses, such as low product yield, slow reaction rate, high separation cost, intolerance to toxic products, and so on. This predominant whole-cell platform suffers from a mismatch between the primary goal of living microbes - cell proliferation and the desired biomanufacturing goal - desired products (not cell mass most times). In vitro synthetic biosystems consist of numerous enzymes as building bricks, enzyme complexes as building modules, and/or (biomimetic) coenzymes, which are assembled into synthetic enzymatic pathways for implementing complicated bioreactions. They emerge as an alternative solution for accomplishing a desired biotransformation without concerns of cell proliferation, complicated cellular regulation, and side-product formation. In addition to the most important advantage - high product yield, in vitro synthetic biosystems feature several other biomanufacturing advantages, such as fast reaction rate, easy product separation, open process control, broad reaction condition, tolerance to toxic substrates or products, and so on. In this perspective review, the general design rules of in vitro synthetic pathways are presented with eight supporting examples: hydrogen, n-butanol, isobutanol, electricity, starch, lactate,1,3-propanediol, and poly-3-hydroxylbutyrate. Also, a detailed economic analysis for enzymatic hydrogen production from carbohydrates is presented to illustrate some advantages of this system and the remaining challenges. Great market potentials will motivate worldwide efforts from multiple disciplines (i.e., chemistry, biology and engineering) to address the remaining obstacles pertaining to cost and stability of enzymes and coenzymes, standardized building parts and modules, biomimetic coenzymes, biosystem optimization, and scale-up, soon. PMID:25447781

Zhang, Yi-Heng Percival

2014-10-27

351

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

352

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

Microsoft Academic Search

BackgroundEnergy 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

Wei-Dong Huang; Y-H Percival Zhang

2011-01-01

353

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

354

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

355

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

356

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 5 L bioreactors and the biomass slurry with 53±4% lipid content (dry weight basis) was treated at 280 °C for 1h with an initial pressure of 500 psi in batch stainless steel reactors. The hydrolysis product was separated and each of the resulting streams was further characterized. The hexane soluble fraction contained fatty acids from the hydrolysis of yeast triacylglycerides, and was low in nitrogen and minerals and could be directly integrated as feedstock into pyrolysis processing to produce biofuels. The proposed hydrothermal treatment addresses some current technological bottlenecks associated with traditional methodologies such as dewatering, oil extraction and co-product utilization. It also enhances the feasibility of using microbial biomass for production of renewable fuels and chemicals. PMID:25034431

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

2014-10-10

357

%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

358

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

359

A DYNAMIC GENERAL EQUILIBRIUM ANALYSIS OF U.S. BIOFUELS PRODUCTION  

Microsoft Academic Search

With the rising global interest in energy security and climate change mitigation, biofuels have gained the prominent attention of researchers and policy makers. The U.S. has emerged as the leading producer of biofuels and is aiming for achieving a target of 36 billion gallons of renewable fuels by 2022 under its updated renewable fuels standard (RFS2) policy. In this paper,

Robert H. Beach; Dileep K. Birur; Lauren M. Davis; Martin T. Ross

2011-01-01

360

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, Å.; Smith, K. A.

2011-12-01

361

Biofuel on contaminated land  

Microsoft Academic Search

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

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

2010-01-01

362

Manipulation of the carbon storage regulator system for metabolite remodeling and biofuel production in Escherichia coli  

PubMed Central

Background Microbial engineering strategies that elicit global metabolic perturbations have the capacity to increase organism robustness for targeted metabolite production. In particular, perturbations to regulators of cellular systems that impact glycolysis and amino acid production while simultaneously decreasing fermentation by-products such as acetate and CO2 make ideal targets. Intriguingly, perturbation of the Carbon Storage Regulator (Csr) system has been previously implicated in large changes in central carbon metabolism in E. coli. Therefore, we hypothesized that perturbation of the Csr system through the CsrA-CsrB ribonucleoprotein complex might increase production of biofuels and their intermediates from heterologous pathways. Results We engaged the CsrA-CsrB ribonucleoprotein complex of E. coli via overexpression of CsrB. CsrB is a 350-nucleotide non-coding RNA that antagonizes CsrA, an RNA-binding protein that regulates translation of specific mRNA targets. By using shotgun proteomics and targeted metabolomics we established that elevation of CsrB levels leads to alterations in metabolite and protein levels in glycolysis, the TCA cycle and amino acid levels. Consequently, we show that such changes can be suitably applied to improve the production of desired compounds through the native fatty acid and heterologous n-butanol and isoprenoid pathways by up to two-fold. We also observed concomitant decreases in undesirable fermentation by-products such as acetate and CO2. Conclusions We have demonstrated that simple engineering of the RNA-based Csr global regulatory system constitutes a novel approach to obtaining pathway-independent improvements within engineered hosts. Additionally, since Csr is conserved across most prokaryotic species, this approach may also be amenable to a wide variety of production hosts. PMID:22694848

2012-01-01

363

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

364

ARE BIOFUELS RENEWABLE ENERGY SOURCES?  

Microsoft Academic Search

The objective of this study is to discuss biofuels renewability in a quantitative point of view. A comprehensive review of the energy balance literature and emergy assessment of biofuels production were carried out at the Laboratory of Ecological Engineering of the Food Engineering School at UNICAMP in order discuss these issues. From these perspective is possible to realize that biofuels

Enrique Ortega; Otávio Cavalett; Consuelo Pereira; Feni Agostinho; John Storfer

365

Biofuels : markets, targets and impacts  

Microsoft Academic Search

This paper reviews recent developments in biofuel markets and their economic, social and environmental impacts. Several countries have introduced mandates and targets for biofuel expansion. Production, international trade and investment have increased sharply in the past few years. However, several existing studies have blamed biofuels as one of the key factors behind the 2007-2008 global food crisis, although the magnitudes

Govinda R. Timilsina; Ashish Shrestha

2010-01-01

366

Closing the gap: global potential for increasing biofuel production through agricultural intensification  

NASA Astrophysics Data System (ADS)

Since the end of World War II, global agriculture has undergone a period of rapid intensification achieved through a combination of increased applications of chemical fertilizers, pesticides, and herbicides, the implementation of best management practice techniques, mechanization, irrigation, and more recently, through the use of optimized seed varieties and genetic engineering. However, not all crops and not all regions of the world have realized the same improvements in agricultural intensity. In this study we examine both the magnitude and spatial variation of new agricultural production potential from closing of 'yield gaps' for 20 ethanol and biodiesel feedstock crops. With biofuels coming under increasing pressure to slow or eliminate indirect land-use conversion, the use of targeted intensification via established agricultural practices might offer an alternative for continued growth. We find that by closing the 50th percentile production gap—essentially improving global yields to median levels—the 20 crops in this study could provide approximately 112.5 billion liters of new ethanol and 8.5 billion liters of new biodiesel production. This study is intended to be an important new resource for scientists and policymakers alike—helping to more accurately understand spatial variation of yield and agricultural intensification potential, as well as employing these data to better utilize existing infrastructure and optimize the distribution of development and aid capital.

Johnston, Matt; Licker, R.; Foley, J.; Holloway, T.; Mueller, N. D.; Barford, C.; Kucharik, C.

2011-07-01

367

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

368

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

PubMed

A combined hydrolysis process, which first mixed dilute acid- and alkali-pretreated corn stover at a 1:1 (w/w) ratio, directly followed by enzymatic saccharification without pH adjustment, has been developed in this study in order to minimize the need of neutralization, detoxification, and washing during the process of lignocellulosic biofuel production. The oleaginous fungus Mortierella isabellina was selected and applied to the combined hydrolysate as well as a synthetic medium to compare fungal lipid accumulation and biodiesel production in both shake flask and 7.5L fermentor. Fungal cultivation on combined hydrolysate exhibited comparable cell mass and lipid yield with those from synthetic medium, indicating that the integration of combined hydrolysis with oleaginous fungal lipid fermentation has great potential to improve performance of advanced lignocellulosic biofuel production. PMID:24768942

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

2014-07-01

369

A self-sustaining advanced lignocellulosic biofuel production by integration of anaerobic digestion and aerobic fungal fermentation.  

PubMed

High energy demand hinders the development and application of aerobic microbial biofuel production from lignocellulosic materials. In order to address this issue, this study focused on developing an integrated system including anaerobic digestion and aerobic fungal fermentation to convert corn stover, animal manure and food wastes into microbial lipids for biodiesel production. Dairy manure and food waste were first anaerobically digested to produce energy and solid digestate (AD fiber). AD fiber and corn stover were then processed by a combined alkali and acid hydrolysis, followed by fungal lipid accumulation. The integrated process can generate 1L biodiesel and 1.9 kg methane from 12.8 kg dry dairy manure, 3.1 kg dry food wastes and 12.2 kg dry corn stover with a positive net energy of 57 MJ, which concludes a self-sustaining lignocellulosic biodiesel process and provides a new route to co-utilize corn stover and organic wastes for advanced biofuel production. PMID:25543542

Zhong, Yuan; Ruan, Zhenhua; Zhong, Yingkui; Archer, Steven; Liu, Yan; Liao, Wei

2015-03-01

370

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

371

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

372

Production of bio-fuel ethanol from distilled grain waste eluted from Chinese spirit making process.  

PubMed

Distilled grain waste eluted from Chinese spirit making is rich in carbohydrates, and could potentially serve as feedstock for the production of bio-fuel ethanol. Our study evaluated two types of saccharification methods that convert distilled grain waste to monosaccharides: enzymatic saccharification and concentrated H2SO4 saccharification. Results showed that enzymatic saccharification performed unsatisfactorily because of inefficient removal of lignin during pretreatment. Concentrated H2SO4 saccharification led to a total sugar recovery efficiency of 79.0 %, and to considerably higher sugar concentrations than enzymatic saccharification. The process of ethanol production from distilled grain waste based on concentrated H2SO4 saccharification was then studied. The process mainly consisted of concentrated H2SO4 saccharification, solid-liquid separation, decoloration, sugar-acid separation, oligosaccharide hydrolysis, and continuous ethanol fermentation. An improved simulated moving bed system was employed to separate sugars from acid after concentrated H2SO4 saccharification, by which 95.8 % of glucose and 85.8 % of xylose went into the sugar-rich fraction, while 83.3 % of H2SO4 went into the acid-rich fraction. A flocculating yeast strain, Saccharomyces cerevisiae KF-7, was used for continuous ethanol fermentation, which produced an ethanol yield of 91.9-98.9 %, based on glucose concentration. PMID:24710703

Tan, Li; Sun, Zhaoyong; Zhang, Wenxue; Tang, Yueqin; Morimura, Shigeru; Kida, Kenji

2014-10-01

373

Nanocrystalline cellulose extraction process and utilization of the byproduct for biofuels production.  

PubMed

Cellulose consists of amorphous and crystalline regions. It is the crystalline regions which may be exploited to produce nanocrystalline cellulose (NCC). In order to extract nanocrystalline cellulose from native cellulose, sulfuric acid hydrolysis is typically used. The amorphous regions of cellulose are hydrolyzed and degraded into soluble products while the crystalline regions remain intact. In an effort to make the NCC extraction process more feasible, a new process was developed to recover and utilize the hydrolyzed regions of cellulose as a byproduct. The acid hydrolyzed amorphous regions were separated and then recovered (regenerated) into solid particles. XRD data revealed that the recovered material is characteristic of cellulose II. Hydrolysis conditions were optimized to maximize the yield of the recovered material and at the same time produce NCC material. Preliminary experiments showed yield values of approximately 61% for the cellulose I crystalline portions and values of about 21.7% for the recovered material (cellulose II). Enzymatic hydrolysis experiments of the recovered material revealed high susceptibility to enzymatic hydrolysis which makes it a promising source for biofuels production. PMID:23465941

Pirani, Sanaa; Hashaikeh, Raed

2013-03-01

374

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

375

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

376

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

377

Overview on Biofuels From a European Perspective  

Microsoft Academic Search

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 biofuel demands. The EU acknowledged

Luigi Ponti; Andrew Paul Gutierrez

2009-01-01

378

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

379

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 to the cellulose a Chemical and Environmental Engineering Department, University of California, Riverside wall structure and thereby allow hydrolyzing enzymes better access to the cellulose core. However, few

California at Riverside, University of

380

Progress in the production and application of n-butanol as a biofuel  

Microsoft Academic Search

Butanol is a very competitive renewable biofuel for use in internal combustion engines given its many advantages. In this review, the properties of butanol are compared with the conventional gasoline, diesel fuel, and some widely used biofuels, i.e. methanol, ethanol, biodiesel. The comparison of fuel properties indicates that n-butanol has the potential to overcome the drawbacks brought by low-carbon alcohols

Chao Jin; Mingfa Yao; Haifeng Liu; Chia-fon F. Lee; Jing Ji

2011-01-01

381

Exploiting diversity and synthetic biology for the production of algal biofuels.  

PubMed

Modern life is intimately linked to the availability of fossil fuels, which continue to meet the world's growing energy needs even though their use drives climate change, exhausts finite reserves and contributes to global political strife. Biofuels made from renewable resources could be a more sustainable alternative, particularly if sourced from organisms, such as algae, that can be farmed without using valuable arable land. Strain development and process engineering are needed to make algal biofuels practical and economically viable. PMID:22895338

Georgianna, D Ryan; Mayfield, Stephen P

2012-08-16

382

Genomic Evaluation of Thermoanaerobacter spp. for the Construction of Designer Co-Cultures to Improve Lignocellulosic Biofuel Production  

PubMed Central

The microbial production of ethanol from lignocellulosic biomass is a multi-component process that involves biomass hydrolysis, carbohydrate transport and utilization, and finally, the production of ethanol. Strains of the genus Thermoanaerobacter have been studied for decades due to their innate abilities to produce comparatively high ethanol yields from hemicellulose constituent sugars. However, their inability to hydrolyze cellulose, limits their usefulness in lignocellulosic biofuel production. As such, co-culturing Thermoanaerobacter spp. with cellulolytic organisms is a plausible approach to improving lignocellulose conversion efficiencies and yields of biofuels. To evaluate native lignocellulosic ethanol production capacities relative to competing fermentative end-products, comparative genomic analysis of 11 sequenced Thermoanaerobacter strains, including a de novo genome, Thermoanaerobacter thermohydrosulfuricus WC1, was conducted. Analysis was specifically focused on the genomic potential for each strain to address all aspects of ethanol production mentioned through a consolidated bioprocessing approach. Whole genome functional annotation analysis identified three distinct clades within the genus. The genomes of Clade 1 strains encode the fewest extracellular carbohydrate active enzymes and also show the least diversity in terms of lignocellulose relevant carbohydrate utilization pathways. However, these same strains reportedly are capable of directing a higher proportion of their total carbon flux towards ethanol, rather than non-biofuel end-products, than other Thermoanaerobacter strains. Strains in Clade 2 show the greatest diversity in terms of lignocellulose hydrolysis and utilization, but proportionately produce more non-ethanol end-products than Clade 1 strains. Strains in Clade 3, in which T. thermohydrosulfuricus WC1 is included, show mid-range potential for lignocellulose hydrolysis and utilization, but also exhibit extensive divergence from both Clade 1 and Clade 2 strains in terms of cellular energetics. The potential implications regarding strain selection and suitability for industrial ethanol production through a consolidated bioprocessing co-culturing approach are examined throughout the manuscript. PMID:23555660

Verbeke, Tobin J.; Zhang, Xiangli; Henrissat, Bernard; Spicer, Vic; Rydzak, Thomas; Krokhin, Oleg V.; Fristensky, Brian; Levin, David B.; Sparling, Richard

2013-01-01

383

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

384

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

385

Liquid biofuels - can they meet our expectations?  

NASA Astrophysics Data System (ADS)

Liquid biofuels are one of the options for reducing the emission of greenhouse gases and the dependence on fossil fuels. This is reflected in the DIRECTIVE 2003/30/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL on the promotion of the use of biofuels or other renewable fuels for transport. The promotion of E10, an automotive fuel containing 10 percent bioethanol, is based on this directive. At present almost all bioethanol is produced from agricultural crops such as maize, corn or sugar beet and sugar cane in suitable climates. In view of shortages and rising prices of food, in particular in developing countries, the use of food and feed crops for biofuel production is increasingly criticized. Alternative sources of biomass are perennial grasses and wood, whose cellulose fraction can be converted to alcohol by the so called "second generation" processes, which seem to be close to commercial deployment. The use of the total plant biomass increases the biofuel yield per hectare as compared to conventional crops. Of special interest for biofuel production is woody biomass from forests as this avoids competition with food production on arable land. Historically woody biomass was for millennia the predominant source of thermal energy. Before fossil fuels came into use, up to 80 percent of a forest was used for fuel wood, charcoal and raw materials such as potash for trade and industry. Now forests are managed to yield up to 80 percent of high grade timber for the wood industry. Replacing sophisticatedly managed forests by fast growing biofuel plantations could make economic sense for land owners when a protected market is guaranteed by politics, because biofuel plantations would be highly mechanized and cheap to operate, even if costs for certified planting material and fertilizer are added. For forest owners the decision to clear existing long rotation forests for biofuel plantations would still be weighty because of the extended time of decades required to rebuild a timber forest if alternative fuel sources would outcompete biofuels in the future. Because second generation bioethanol plants are technically complex and will require substantial amounts of biomass - at least at current perception - the impact of large scale conversion of arable and forests to biofuel plantations on biodiversity, ground water, rural communities, tourism as well as traffic and transport, just to mention a few, must be considered. Another factor is storability of biomass. Whole plant and woody biomass is much more difficult to store than grains and a steady flux from the plantation to the mill might be difficult to sustain under adverse weather conditions.

Glatzel, G.

2012-04-01

386

Measuring and moderating the water resource impact of biofuel production and trade  

NASA Astrophysics Data System (ADS)

Energy systems and water resources are inextricably linked, especially in the case of bioenergy, which can require up to three orders of magnitude more water than other energy carriers. Water scarcity already affects about 1 in 5 people globally, and stands to be exacerbated in many locales by current biofuel expansion plans. This dissertation engages with several of the analytical and governance challenges raised by this connection between bioenergy expansion and global water resources. My examination begins with an overview of important concepts in water resource analysis, followed by a review of current literature on the water impacts of most major energy pathways. I then report on a case study of ethanol fuel in California. This work employed a coupled agro-climatic and life cycle assessment (LCA) model to estimate the water resource impacts of several bioenergy expansion scenarios at a county-level resolution. It shows that ethanol production in California regularly consumes more than 1000 gallons of water per gallon of fuel produced, and that 99% of life-cycle water consumption occurs in the feedstock cultivation phase. This analysis then delves into the complexity of life cycle impact assessment for water resources. Despite improvements in water accounting methods, impact assessment must contend with the fact that different water sources are not necessarily commensurable, and that impacts depend on the state of the resource base that is drawn upon. I adapt water footprinting and LCA techniques to the bioenergy context, describing comprehensive inventory approaches and developing a process for characterizing (weighting) consumption values to enable comparison across resource bases. This process draws on metrics of water stress, accounting for environmental flow requirements, climatic variability, and non-linearity of water stress effects. My assessment framework was developed in hopes that it would be useful in managing the risks and impacts it describes. The primary actors in this governance effort are government regulators, whose policies and incentives continue to drive and to shape the expansion of the bioenergy industry. However, the ability of governments to manage the impacts of biofuels is severely constrained by their obligations under international trade law. This dissertation concludes, therefore, with a detailed investigation into relevant precedents under the General Agreement on Tariffs and Trade (GATT) and the World Trade Organization (WTO). I use these precedents to identify the policy tools that governments would be able to bring to bear in moderating the water resource impacts and myriad other environmental and social concerns raised by bioenergy expansion.

Fingerman, Kevin Robert

387

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

388

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

389

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

390

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

391

Biofuels: balancing risks and rewards.  

PubMed

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

2013-02-01

392

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

393

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.

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

394

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...

395

Biofuels from microalgae.  

PubMed

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 biofuels can be coupled with flue gas CO2 mitigation, wastewater treatment, and the production of high-value chemicals. Microalgal farming can also be carried out with seawater using marine microalgal species as the producers. Developments in microalgal cultivation and downstream processing (e.g., harvesting, drying, and thermochemical processing) are expected to further enhance the cost-effectiveness of the biofuel from microalgae strategy. PMID:18335954

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

2008-01-01

396

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.

Science Channel

397

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

398

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

399

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

400

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

401

Carbon Calculator for Land Use Change from Biofuels Production (CCLUB). Users' manual and technical documentation.  

SciTech Connect

The Carbon Calculator for Land Use Change from Biofuels Production (CCLUB) calculates carbon emissions from land use change (LUC) for four different ethanol production pathways including corn grain ethanol and cellulosic ethanol from corn stover, miscanthus, and switchgrass. This document discusses the version of CCLUB released May 31, 2012 which includes corn, as did the previous CCLUB version, and three cellulosic feedstocks: corn stover, miscanthus, and switchgrass. CCLUB calculations are based upon two data sets: land change areas and above- and below-ground carbon content. Table 1 identifies where these data are stored and used within the CCLUB model, which is built in MS Excel. Land change area data is from Purdue University's Global Trade Analysis Project (GTAP) model, a computable general equilibrium (CGE) economic model. Section 2 describes the GTAP data CCLUB uses and how these data were modified to reflect shrubland transitions. Feedstock- and spatially-explicit below-ground carbon content data for the United States were generated with a surrogate model for CENTURY's soil organic carbon sub-model (Kwon and Hudson 2010) as described in Section 3. CENTURY is a soil organic matter model developed by Parton et al. (1987). The previous CCLUB version used more coarse domestic carbon emission factors. Above-ground non-soil carbon content data for forest ecosystems was sourced from the USDA/NCIAS Carbon Online Estimator (COLE) as explained in Section 4. We discuss emission factors used for calculation of international greenhouse gas (GHG) emissions in Section 5. Temporal issues associated with modeling LUC emissions are the topic of Section 6. Finally, in Section 7 we provide a step-by-step guide to using CCLUB and obtaining results.

Mueller, S; Dunn, JB; Wang, M (Energy Systems); (Univ. of Illinois at Chicago)

2012-06-07

402

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

403

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

404

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

405

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 with pasture-feedlot manage-· ment alternatives. Assess economic implications of beef production using an array character- istics of beef that may provide an alternative lean-to-fat composition for consum- ers. http

406

Nutrient management studies in biofuel cropping systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

Research was conducted to determine the effect of nutrient management practices on biofuel crop production, and to evaluate long term effects of biofuel crop production on selected chemical, physical and microbiological properties. Experimental plots for research on biofuel crop production were esta...

407

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

408

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.

409

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

410

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

411

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 is 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 CO2 or, consequently, to global warming.

Robert M. Boddey

1995-01-01

412

Butanol (a superior biofuel) production from agricultural residues (renewable biomass): recent progress in technology  

Technology Transfer Automated Retrieval System (TEKTRAN)

This article reviews bioconversion of plant materials such as wheat straw (WS), corn stover (CS), barley straw (BS), and switchgrass (SG) to butanol and process technology that converts these materials into this superior biofuel. Successful fermentation of low value WS makes butanol fermentation ec...

413

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 COâ or, consequently, to global warming.

R. M. Boddey

1995-01-01

414

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

415

The Crossover Biorefinery in The Production of Liquid Biofuels and Bioderived Chemicals from Biomass: Emerging Technologies  

Technology Transfer Automated Retrieval System (TEKTRAN)

Energy security and climate change imperatives require large-scale substitution of petroleum-based fuels over the next 15 years. Biofuels offer a diverse range of promising alternatives. Biomass is the only known, large-scale, renewable resource that can be converted into liquid fuels for transpor...

416

Biofuel production from catalytic thermochemical conversion of animal manure and biomass  

Technology Transfer Automated Retrieval System (TEKTRAN)

The objective of the research is to identify suitable catalysts to convert animal manure-based and biomass-based synthesis gas (syngas) to liquid biofuels such as mixed alcohols and hydrocarbons. Two pathways of catalytically converting syngas are investigated: (1)a two-step process involving the in...

417

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

E-print Network

will be able to model a safer, greener, and more economically sustainable way of doing business that can expansion by improving the business model. Through a partnership with Piedmont Biofuels, and the addition · Technology development stage of project: Stage 3, Commercial Facilities · Quantity of primary fuel

418

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 20–50% of dry weight) of neutral lipid stored in cytosolic lipid bodies. A successful and economically viable algae based biofuel industry mainly depends on the selection of appropriate algal strains. The

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

2011-01-01

419

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

420

Increasing corn for biofuel production reduces biocontrol services in agricultural landscapes  

E-print Network

in these 4 states. Recent biofuel-driven growth in corn planting results in lower landscape diversityCentre for Crop Systems Analysis, Department of Plant Sciences, Wageningen University, P.O. Box 430, 6700 AK ecosystem services High recent prices of oil and a growing interest in developing alternative liquid fuels

Landis, Doug

421

Predicting agricultural management influence on long-term soil organic carbon dynamics: implications for biofuel production  

Technology Transfer Automated Retrieval System (TEKTRAN)

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,...

422

Biomass composition of perennial grasses for biofuel production in North Dakota, USA  

Technology Transfer Automated Retrieval System (TEKTRAN)

Successful development of biofuels from biomass feedstocks depends on high yields and acceptable quality. We investigated the chemical composition of ten perennial grasses and mixtures across environments in North Dakota, USA. The contents of neutral detergent fiber, acid detergent fiber, acid deter...

423

Soil Nitrous Oxide Emissions with Crop Production for Biofuel: Implications for Greenhouse Gas Mitigation  

Technology Transfer Automated Retrieval System (TEKTRAN)

The growing biofuel commodity market for corn ethanol has the potential to reduce direct greenhouse gas (GHG) emissions associated with fossil fuel combustion in the US. However, projected increases in cropland to accommodate this energy-based commodity will also impact emissions of GHGs from soils...

424

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

425

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

426

Regional Algal Biofuel Production Potential in the Coterminous United States as Affected by Resource Availability Trade-offs  

SciTech Connect

The warm sunny climate and unoccupied arid lands in the American southwest are favorable factors for algae cultivation. However, additional resources affect the overall viability of specific sites and regions. We investigated the tradeoffs between growth rate, water, and CO2 availability and costs for two strains: N. salina and Chlorella sp. We conducted site selection exercises (~88,000 US sites) to produce 21 billion gallons yr-1 (BGY) of renewable diesel (RD). Experimental trials from the National Alliance for Advanced Biofuels and Bio-Products (NAABB) team informed the growth model of our Biomass Assessment Tool (BAT). We simulated RD production by both lipid extraction and hydrothermal liquefaction. Sites were prioritized by the net value of biofuel minus water and flue gas costs. Water cost models for N. salina were based on seawater and high salinity groundwater and for Chlorella, fresh and brackish groundwater. CO2 costs were based on a flue gas delivery model. Selections constrained by production and water were concentrated along the Gulf of Mexico and southeast Atlantic coasts due to high growth rates and low water costs. Adding flue gas constraints increased the spatial distribution, but the majority of sites remained in the southeast. The 21 BGY target required ~3.8 million hectares of mainly forest (41.3%) and pasture (35.7%). Exclusion in favor of barren and scrub lands forced most production to the southwestern US, but with increased water consumption (5.7 times) and decreased economic efficiency (-38%).

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

2014-03-15

427

Biofuels and water: an exploration  

Microsoft Academic Search

Biofuel production will affect water resources, especially on a regional and local scale. This happens through increased crop production and its associated use of agro-chemicals, water requirements for ethanol processing factories, and through the expected conversion of natural areas providing important water-related services to rural as well as urban areas. It is suggested to include (effects of) biofuels in current

Gerdien Meijerink; J. W. A. Langeveld; P. J. G. J. Hellegers

2008-01-01

428

Assessing the environmental sustainability of biofuels  

E-print Network

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...

Kazamia, Elena; Smith, Alison G.

2014-09-30

429

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

430

Effect of catalyst additives on the production of biofuels from palm oil cracking in a transport riser reactor.  

PubMed

Catalytic cracking of crude palm oil (CPO) and used palm oil (UPO) were studied in a transport riser reactor for the production of biofuels at a reaction temperature of 450 degrees C, with residence time of 20s and catalyst-to-oil ratio (CTO) of 5 gg(-1). The effect of HZSM-5 (different Si/Al ratios), beta zeolite, SBA-15 and AlSBA-15 were studied as physically mixed additives with cracking catalyst Rare earth-Y (REY). REY catalyst alone gave 75.8 wt% conversion with 34.5 wt% of gasoline fraction yield using CPO, whereas with UPO, the conversion was 70.9 wt% with gasoline fraction yield of 33.0 wt%. HZSM-5, beta zeolite, SBA-15 and AlSBA-15 as additives with REY increased the conversion and the yield of organic liquid product. The transport riser reactor can be used for the continuous production of biofuels from cracking of CPO and UPO over REY catalyst. PMID:19138514

Chew, Thiam Leng; Bhatia, Subhash

2009-05-01

431

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

432

A New Biofuels Technology Blooms in Iowa  

SciTech Connect

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

2010-01-01

433

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

434

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

435

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

436

Feasibility of filamentous fungi for biofuel production using hydrolysate from dilute sulfuric acid pretreatment of wheat straw  

PubMed Central

Background Lipids produced from filamentous fungi show great promise for biofuel production, but a major limiting factor is the high production cost attributed to feedstock. Lignocellulosic biomass is a suitable feedstock for biofuel production due to its abundance and low value. However, very limited study has been performed on lipid production by culturing oleaginous fungi with lignocellulosic materials. Thus, identification of filamentous fungal strains capable of utilizing lignocellulosic hydrolysates for lipid accumulation is critical to improve the process and reduce the production cost. Results The growth performances of eleven filamentous fungi were investigated when cultured on glucose and xylose. Their dry cell weights, lipid contents and fatty acid profiles were determined. Six fungal strains with high lipid contents were selected to culture with the hydrolysate from dilute sulfuric acid pretreatment of wheat straw. The results showed that all the selected fungal strains were able to grow on both detoxified liquid hydrolysate (DLH) and non-detoxified liquid hydrolysate (NDLH). The highest lipid content of 39.4% was obtained by Mortierella isabellina on NDLH. In addition, NDLH with some precipitate could help M. isabellina form pellets with an average diameter of 0.11?mm. Conclusion This study demonstrated the possibility of fungal lipid production from lignocellulosic biomass. M. isabellina was the best lipid producer grown on lignocellulosic hydrolysates among the tested filamentous fungi, because it could not only accumulate oils with a high content by directly utilizing NDLH to simplify the fermentation process, but also form proper pellets to benefit the downstream harvesting. Considering the yield and cost, fungal lipids from lignocellulosic biomass are promising alternative sources for biodiesel production. PMID:22824058

2012-01-01

437

Ethanol in the Environment ? A Critical Review of its Roles as a Natural Product, a Biofuel and a Potential Environmental Pollutant  

Microsoft Academic Search

Ethanol has long been known as a natural product of fermentation and an important industrial chemical. Recently it has been recognised as a useful biofuel. However, the overview of the global environmental cycle of ethanol in vegetation, wetlands, the ocean and the atmosphere has so-far been neglected. Ethanol is a key product of higher plants under oxygen-deficient conditions, and the

WAYNE V. KIRSTINE; IAN E. GALBALLY

2011-01-01

438

Turning Bacteria into Fuel: Cyanobacteria Designed for Solar-Powered Highly Efficient Production of Biofuels  

SciTech Connect

Broad Funding Opportunity Announcement Project: ASU is engineering a type of photosynthetic bacteria that efficiently produce fatty acids—a fuel precursor for biofuels. This type of bacteria, called Synechocystis, is already good at converting solar energy and carbon dioxide (CO2) into a type of fatty acid called lauric acid. ASU has modified the organism so it continuously converts sunlight and CO2 into fatty acids—overriding its natural tendency to use solar energy solely for cell growth and maximizing the solar-to-fuel conversion process. ASU’s approach is different because most biofuels research focuses on increasing cellular biomass and not on excreting fatty acids. The project has also identified a unique way to convert the harvested lauric acid into a fuel that can be easily blended with existing transportation fuels.

None

2010-01-01

439

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

Microsoft Academic Search

Energy crises, global warming, and climatic changes call for technological and commercial advances in manufacturing high-quality\\u000a transportation fuels from unconventional feedstocks. Microalgae is one of the most promising sources of biofuels due to the\\u000a 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

Luísa Gouveia; Ana Evangelista Marques; Teresa Lopes da Silva; Alberto Reis

2009-01-01

440

Mass-cultivation of carbohydrate rich macroalgae, a possible solution for sustainable biofuel production  

Microsoft Academic Search

Global demand for bio-fuels continues unabated. Rising concerns over environmental pollution and global warming have encouraged\\u000a the movement to alternate fuels, the world ethanol market is projected to reach 86 billion litres this year. Bioethanol is\\u000a currently produced from land-based crops such as corn and sugar cane. A continued use of these crops drives the food versus\\u000a fuel debate. An

Stefan Kraan