ORNL report: imports from Latin America may help US meet energy goals - 30 to 85 billion gallons available for export by 2017

The Biopact's take on bioenergy has always been one of interdependence and global trade, instead of localism and energy nationalism. Biofuels and bioproducts must be produced there where it can be done in the most efficient and cost-effective manner, and where it yields most social, environmental and economic benefits. We focused on a potential win-win relationship between Africa and Europe. Now researchers from the Oak Ridge National Laboratory (ORNL) did the same for the United States and Latin America.

In a very comprehensive report released today they find that Latin American nations could become important suppliers of efficient, environmentally-friendly and cost-effective ethanol for world markets in coming decades. U.S. imports, they say, can bring significant "mutual benefits" and may benefit development in poorer countries. Many of the findings once again reflect the case Biopact has been making all along (and which was substantiated by another recent study that analysed a global 'biopact' - previous post).

The study, Biofuel Feedstock Assessment for Selected Countries, presents findings from research conducted in support of a larger study of “Worldwide Potential to Produce Biofuels with a focus on U.S. Imports” by the Department of Energy. The ORNL study highlights the importance of Brazil’s dynamic sugarcane industry in future world trade in fuel ethanol.

A team of ORNL researchers led by Keith Kline and Gbadebo Oladosu projected that a select group of countries alone - Brazil, Argentina, Colombia and members of the Caribbean Basin Initiative - could produce sufficient feedstock for more than 30 billion gallons of ethanol per year by 2017, which would represent a six-fold increase over current production. If Canada, China, India and Mexico are included, the total potential available for exports could be as high as 85 billion gallons of gasoline equivalent (graph, click to enlarge). Nearly 40 percent of the projected supply in 2017 is based on the potential to use new technology to produce advanced biofuels from cellulosic feedstock using crop residues and forestry byproducts.

Current feedstock production, based on traditional crops such as sugarcane, soybeans and palm oil, has the potential to double or triple by 2017 in some cases. Supply growth is derived from increasing the area cultivated, supplemented by improving yields and farming practices. - Gbadebo A. Oladosu, the lead economist

Although it was not a focus for this research, the researchers highlighted implications for potential land use change. The ORNL report assembles historic data on feedstock production for multiple countries and crops and calculates future production and the potential supplies available for export. Included in the report are detailed graphs, tables and disaggregated data for feedstock supplies under a range of future growth possibilities.

The supply projections provide analysts and policymakers with better data on which to base decisions. The potential for future biofuel feedstock production in Latin America offers interesting opportunities for the U.S. and developing nations. - Keith L. Kline, lead author

Results suggest that an increasing portion of U.S. fossil fuel imports that now arrive from distant nations in Africa and the Middle East Asia could be replaced by renewable biofuels from neighbors in the Americas.

'Mutual benefits', a Biopact of sorts
Paul Leiby, an ORNL expert on energy security, notes that ethanol from trading partners in this hemisphere could offer many mutual benefits: more reliable and diversified U.S. fuel supply, improved rural livelihoods in Latin America, reductions in greenhouse gas emissions and the expanded availability of biofuel in many urban markets via delivery at coastal ports:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: ethanol :: biodiesel :: trade :: efficiency :: interdependence :: developing countries :: Latin America ::

Biofuel imports complement domestic biofuel production and diminish reliance on oil, the price of which is unstable and strongly influenced by the OPEC cartel. Even if imported, biofuels can improve our energy security by reducing oil imports and expanding our base of independent fuel sources. Best of all, American consumers could pay less at the pump during energy emergencies. - Leiby

ORNL’s study focuses on assessing future potential for feedstock production in Argentina, Brazil, Canada, China, Colombia, India, Mexico and the Caribbean Basin region. Countries were selected based on their potential to impact world biofuel markets, proximity to the U.S. and other criteria. The research team hopes to expand the analysis to include additional nations in Asia and Africa over the coming year.

The report provides supply curves for selected countries and feedstocks projected to 2012, 2017 and 2027. Highlights include:

• If the total projected feedstock supply calculated as “available” for export or biofuel in 2017 from these countries were converted to biofuel, it would represent the equivalent of about 38 billion gallons of gasoline. [See Figure]
• Sugarcane and bagasse, the solid residue after juices are pressed from the sugarcane stalk, form the bulk of potential future feedstock supplies, representing about two-thirds of the total available for export or biofuel in 2017.
• Soybeans are next in importance in terms of available supply potential in 2017, representing about 18 percent of the total.
• Most future supplies of corn and wheat are projected to be allocated to food and feed and would not be available for biofuels. Canada may be an exception because government programs will likely cause these crops to be used as feedstock to meet their domestic biofuel targets over the coming decade.
• In the various countries assessed, recent changes in national policies and laws are catalyzing investments in biofuel industries to meet targets for fuel blending that generally fall in the 5 percent to 10 percent range.
• Social and environmental concerns associated with the expansion of feedstock production are considered in the report, including land availability and efforts to establish systems for certification of sustainable production.
• Sugarcane dominates potential supply among the crops studied while bagasse – the crushed stalk residue from sugarcane processing – and forest industry residues are the principle sources among potential cellulosic supplies.

Also contributing to the ORNL report were Bob Perlack, Amy Wolfe and Virginia Dale of ORNL’s Environmental Sciences Division and Matt McMahon, a summer intern from Appalachian State University.

This research was jointly funded by DOE’s Office of Policy and International Affairs and the Office of Energy Efficiency and Renewable Energy, Biomass Programs. UT-Battelle manages Oak Ridge National Laboratory for the Department of Energy.

References:

Keith L. Kline, Gbadebo A. Oladosu, Amy K. Wolfe, Robert D. Perlack, Virginia H. Dale, Matthew McMahon, Biofuel Feedstock Assessment for Selected Countries [*.pdf], Prepared for U.S. Department of Energy Office of Policy and International Programs and the EERE Office of the Biomass Program; To Support the DOE study of Worldwide Potential to Produce Biofuels with a focus on U.S. Imports - February 2008.

Biopact: Study: Global Biopact on biofuels can bring benefits to both rich and poor nations - February 20, 2008

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Researchers visualize complex pigment mixtures in living cells: technique offers new insights into photosynthesis at molecular level

In a technical advance that could allow researchers to watch cells as they act during the process of photosynthesis, scientists funded by the U.S. Department of Energy have developed a method that extends the power of fluorescence-mediated bio-imaging to see discrete pigments inside live cells of bacteria. The method is providing fresh insights into what happens on a molecular level during photosynthesis. It also promises to provide important information about the inner workings of cells as they engage in the photosynthesis process of collecting sunlight and turning it into chemical energy. The new tool is set to become an integral part of "systems biology".

The new capacity to gather information about photosynthesis this way could be valuable in helping researchers fine tune the bacteria for specific purposes, said Wim Vermaas, a professor in Arizona State University's (ASU) School of Life Sciences, member of the university's Center for Bioenergy and Photosynthesis and lead author.

The article titled "In vivo hyperspectral confocal fluorescence imaging to determine pigment localization and distribution in cyanobacterial cells" was published in this week’s online Early Edition of the Proceedings of the National Academy of Sciences. The ASU researchers worked with scientists from Sandia National Laboratories, Albuquerque, on the new method.

The method is based on fluorescence imaging to discern the different pigments of bacteria that are engaged in photosynthesis. Fluorescence is a property where some compounds emit a characteristic glow when excited by specific wavelengths of light. Up until now, current fluorescent methods have had a hard time discerning compounds with similar pigments and fluorescence characteristics, hampering the ability of researchers to know exactly what is going on inside a cell.

Confocal fluorescence microscopy has proven to be an excellent method to localize pigments in cells as long as there is little spectral overlap between different fluorescing pigments. The new method, "hyperspectral fluorescence imaging", greatly pushes the boundaries of this technique, and can separately localize pigments with similar fluorescence spectra. The researchers employed an advanced image analysis method that was developed at Sandia Labs.

This is a new tool in our tool box, and a very good one at that. [...] This is an analysis method that is superior to what commercial analysis systems can do. It tells you where the fluorescent materials are in the cell, what the fluorescence of each material looks like and how much is present even if the fluorescence properties look like each other. - Professor Wim Vermaas, lead author

The initial study focused on localization of pigments in a cyanobacterium, a specific type of bacteria of interest to the team. With the method, they showed that photosynthesis-related pigments (chlorophylls, phycobilins and carotenoids) can be localized in vivo in cells of the cyanobacterium Synechocystis sp. PCC 6803 through deconvolution of individual fluorescence emission spectra in small (0.03 cubic micrometer) volumes by means of hyperspectral confocal fluorescence imaging:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: plant cell :: metabolism :: photosynthesis :: cyanobacteria :: bio-imaging ::

The method allows us to push the resolution limits of confocal fluorescence microscopy, particularly when there are mixtures of different fluorescent compounds with relatively similar spectra. In the specific case of cyanobacteria, it enables the detection of different pigments relative to each other in the cell, and we were able to localize the two different photosystems in the cell relative to each other, along with other pigments. - Professor Vermaas

Using the technique, the researchers report that results obtained indicate a heterogeneous composition of thylakoid membranes in cyanobacteria: Phycobilin emission was most intense along the periphery of the cell whereas chlorophyll fluorescence was distributed more evenly throughout the cell, suggesting that fluorescing phycobilisomes are more prevalent along the outer thylakoids. Carotenoids were prevalent in the cell wall and also were present in thylakoids.

Two chlorophyll fluorescence components also were resolved: the short-wavelength component originated primarily from photosystem II and was most intense near the periphery of the cell; and the long-wavelength component that is attributed to photosystem I, because it disappears in mutants lacking this photosystem, was of higher relative intensity toward the inner rings of the thylakoids. Together, the results suggest compositional heterogeneity between thylakoid rings, with the inner thylakoids enriched in photosystem I.

Vermaas said this means that even in a simple and small cyanobacterial cell (about a hundred fold smaller than can be seen by the human eye) there is an exquisite functional division of labor between membranes inside the cell, with different processes in photosynthesis in different areas of the membranes.

We found that the two photosystems are not fully co-localized in thylakoids in the cell, even though thylakoids ‘look all the same’ in electron micrographs. Based on this, the way the cells probably work, is that the inner thylakoids primarily make ATP (adenosine triphosphate), the energy currency of the cell, by cyclic electron transport around photosystem I, and the peripheral ones do linear electron flow resulting in ATP as well as reduced nicotinamide adenine dinucleotide phosphate, the carrier of reducing equivalents used for carbon dioxide fixation.

The bottom line here is that even if cell ‘compartments,’ like thylakoid membranes, cannot be distinguished in an electron microscope, there is a functional heterogeneity, because of different protein complexes in different parts of the thylakoids. This heterogeneity had long been suspected, but never been proven experimentally.

These results show that hyperspectral fluorescence imaging can provide new information regarding pigment organization and localization even in small cells, and provides a new approach in in vivo localization of complex mixtures of fluorescing compounds at high resolution. - Professor Vermaas

Hyperspectral fluorescence imaging is computationally intensive when investigating cells with multiple fluorescing pigments, but the results thus far illustrate the great power of the technique in recognizing the detailed localization of fluorescing compounds inside small cells, Vermaas said. This work opens up new vistas for localization of several different proteins, pigments and other fluorescing compounds inside a cell, and this type of imaging is likely to become an integral tool for “systems biology,” which seeks to holistically analyze the interplay between proteins, metabolites and the energy/redox state of the cell in order to understand how cells function.

The work was funded by the U.S. Department of Energy.

Image: Hyperspectral imaging scans through wild-type Synechocystis cells. Credit: Vermaas, et. al., PNAS.

References:
Vermaas, W.F.J., et. al. "In vivo hyperspectral confocal fluorescence imaging to determine pigment localization and distribution in cyanobacterial cells", PNAS, Published online on March 3, 2008, DOI: 10.1073/pnas.0708090105

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USDA and DOE to invest up to $18.4 million for 21 biomass RD&D projects: heat, power, biofuels and bioproducts

The U.S. Department of Agriculture (USDA) and the U.S. Department of Energy (DOE) today announced that combined, USDA and DOE will invest up to $18.4 million, over three years, for 21 biomass research and development (R&D), and demonstration projects that will contribute to creating the bioeconomy. These projects specifically aim to address critical barriers to making production of biomass based products - electricity, heat, biofuels and bio-based products - more efficient and cost-effective.

The projects were announced today at the opening of the Washington International Renewable Energy Conference (WIREC 2008). They are integral to furthering the Advanced Energy Initiative, which aims to change the way in which the U.S. powers its cars, homes and business by increasing energy efficiency and diversifying energy sources in effort to increase energy, economic and national security.

Funding for these projects will be provided through the Biomass Research and Development Initiative (BRDI), a joint USDA-DOE effort established in 2000 to develop the next generation of clean, bio-based technologies. The BRDI's Technical and Scientific Committee recently released its Roadmap for Bioenergy and Biobased Products in the United States [*.pdf].

The following entities have been selected as grant recipients:

Research & Development projects

Rutgers, The State University of New Jersey (NJ) – up to $971,799: Grant Purpose: To develop a U.S. native grass breeding consortium to identify regional optimum biomass productivity on marginal lands and switchgrass performance in specific U.S. regions.

Agrivida, Inc. (MA) - up to $982,589: Grant Purpose: To study altered plant compositions for improved biofuel production. This will include analysis of rice straw, sorghum, and switchgrass performance in specific U.S. regions (Agrivida is a key player in third generation biofuel crops).

University of Florida (FL) - up to $866,576: Grant Purpose: To address genetic engineering of sugarcane for increased fermentable sugar yield from hemicellulosic biomass in Florida.

Ceres, Inc. (CA) - up to $839,909: Grant Purpose: To identify and characterize plant genes involved in biosynthesis and deposition of cellulose and hemicellulose in plant cell walls, with a focus on switchgrass throughout the U.S.

Ceres, Inc. (CA) - up to $883,290: Grant Purpose: To evaluate herbacious and woody crops for use in thermochemical processing, specifically examining willow and switchgrass species grown throughout a wide range of geographies in the U.S.

Regents of the University of Colorado (CO) - up to $1,000,000: Grant Purpose: To develop rapid solar-thermal chemical reactor systems for conversion of biomass to synthesis gas.

North Carolina State University (NC) - up to $999,889: Grant Purpose: To develop advanced technology for low-cost ethanol from engineered cellulosic biomass.

Regents of the University of Minnesota (MN) - up to $975,676: Grant Purpose: To develop a microwave-assisted pyrolysis system for conversion of cellulosic biomass to bio-oils.

energy :: sustainability :: biomass :: bioenergy :: biofuels :: cellulosic ethanol :: gasification :: pyrolysis :: bioconversion :: energy crops :: bioproducts :: bioeconomy ::

Regents of the University of Minnesota (MN) - up to $715,340: Grant Purpose: To develop pathways to achieving U.S. bioenergy policy goals, develop economic costs and environmental impacts, and identify potential technological bottlenecks.

Regents of the University of Minnesota (MN) - up to $576,368: Grant Purpose: To research and analyze lignin as a facilitator during saccharification by brown rot fungi.

University of Kentucky Research Foundation (KY) - up to $999,964: Grant Purpose: To develop advanced ceramic materials for the separation and recovery of high-value pentose derivatives from cellulosic biomass using molecular imprinting.

Battelle Memorial Institute, on behalf of DOE’s Pacific Northwest National Laboratory (WA) - up to $1,000,000: Grant Purpose: To address catalytic conversion of biomass to fuels and chemicals using ionic liquids.

Packer Engineering (IL) - up to $1,000,000: Grant Purpose: To research and develop on-farm conversion of biomass to synthetic gas, combined heat and electric power, and fertilizer.

Kansas State University (KS) - up to $690,000: Grant Purpose: To demonstrate pelletizing forage crops and perennial grasses in the field to increase cellulosic ethanol production.

The University of Akron (OH) - up to $743,904: Grant Purpose: To research and develop supercritical methods for biorefinery of rubber-bearing guayule biomass.

Purdue University (IN) - up to $1,000,000: Grant Purpose: To develop a low-cost, high-yield process for direct production of high energy density liquid fuel from biomass. Synergistic use of solar hydrogen with biomass will be explored.

Iowa State University (IA) - up to $944,899: Grant Purpose: To develop catalytic production of ethanol from biomass-derived synthesis gas.

Cornell University (NY) - up to $998,943: Grant Purpose: To develop more effective enzymatic conversion processes through nano-scale elucidation of molecular mechanisms and kinetic modeling.

GE Global Research (NY) - up to $820,035: Grant Purpose: To integrate biomass gasification with catalytic partial oxidation for tar conversion.

Demonstration projects

Texas Engineering Experimental Station (TX) - up to $600,000: Grant Purpose: To provide a demonstration of commercial feasibility of anaerobic fermentation of biomass for the production of carboxylate salts and their conversion to keytones.

Washington State University (WA) - up to $839,909: Grant Purpose: To provide product diversification strategies for a new generation of biofuels and bio-products.

Grant recipients are required to raise a minimum of 20 percent matching funds for R&D projects, and 50 percent matching funds for demonstration projects. Of the $18,449,089 announced today, USDA will provide up to $13,225,554, and DOE will provide up to $5,223,535 (Fiscal Years 2007-2009). Grants are subject to negotiation and will begin immediately, and funding is subject to appropriations from Congress.

Secretaries Ed Schafer (USDA) and Samuel Bodman (US DOE) made today’s announcement while delivering remarks at the Washington International Renewable Energy Conference 2008 (WIREC).The funding announcement was made at WIREC 2008, held in Washington this week, which aims to garner broad, high-level international support for developing and deploying clean, renewable energy technologies as a key mechanism for increasing energy security, mitigating climate change, improving air quality and promoting sustainable development. In addition to raising political support for, and public awareness of the importance of renewable energy, WIREC also includes broad market opportunities for agricultural producers in the rural sector worldwide. WIREC 2008 is the third global ministerial-level conference on renewable energy, following events in Beijing in 2005 and Bonn in 2004.

References:
USDA/DOE: Biomass Research and Development Initiative

Advanced Energy Initiative.

BRDI: Roadmap for Bioenergy and Biobased Products in the United States [*.pdf] - October 2007.

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Energy Quest and Chilean farmers in joint biomass gasification project to produce synthetic diesel

Energy Quest, Inc. an emerging alternative energy company focusing on the development and production of hydrogen-enriched alternative fuels announced the signing of a Letter of Intent (LOI) with Etanol del Pacifico Sur S.A. (EPSSA), an association of medium scale farmers in Chile. The letter sets forth the basic terms and conditions under which Energy Quest expects to enter into a joint venture with for the construction of an 82,000 liter per day waste biomass gasification synthetic diesel plant in Las Cabras, Chile.

The implementation of this technological innovation in the country will surely mark a milestone for the development of ecological fuels in the whole region. We believe this will not only allow an important reduction in global warming emissions, but specially in the case of Chile, it should serve to ease its strong dependency on imported oil. - Jaime Eidelstein, South America Representative for Energy Quest

Energy Quest will provide the proprietary technologies and equipment for the complete gasification synthetic diesel plant, while EPSSA will provide the feedstock of waste biomass from their existing corn growing operations. Energy Quest and EPSSA anticipate achieving engineering and commercial breakthroughs enabling the gasification of agricultural waste biomass for the profitable production of alternative green energy. The company plans to rapidly move forward subject to the mutual agreement of the terms and conditions set forth in the project proposal in addition to the completion of a joint venture agreement.

The basic terms of the proposed project agreement call for the establishment of a joint venture with EPSSA, whereby they would contribute proportionally resulting in ownership of 40% EPSSA and 60% EQI. EPSSA will contribute the waste biomass feed stock:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: gasification :: synthetic biofuels :: biomass-to-liquids :: Chile ::

EQI will provide patents, intellectual properties, equipment, management and financing. The equity of the proposed plant when complete is expected to be US$32 million. Following commissioning and start up, expected to be completed within 12 months from the signing of the joint venture agreement, the joint venture anticipates immediate cash flows with gross annual revenues of $16.6 million while yielding a net profit of $7.1 million after taxes and debt payment.

We are pleased to have secured this opportunity with EPSSA. This project will be the first EQI installation of its gasification synthetic diesel system in South America. We expect this venture to pave the way for additional mutually beneficial opportunities in South America. - Wilf Ouellette, President and CEO of Energy Quest

Etanol del Pacífico Sur S.A., a maize farmers association, was formed in 2006 by 150 mid-sized farmers with a total of 8,000 hectares under corn production in Las Cabras, just south of Santiago, Chile. They also aim to build a US$25 million corn to ethanol plant that will produce 40-50 million liters of bio-ethanol a year.

Energy Quest is a diversified energy company with interests in both conventional and renewable energy sources. Its mission is to bring new technologies to bear to enhance existing energy production as well as developing new energy sources. The immediate objective of the company is to secure energy projects using the PyStR and M2 gasifier and the acquisition of existing, profitable Alternate Energy companies. This would provide significant positive cash flow to the company while being an ideal location for development, demonstration, and operation of many of the company's new technologies. This is the first of many new technologies Energy Quest plans to announce and deploy over the coming months that will demonstrate that it is possible for an energy company to be both environmentally friendly and highly profitable.

Energy Quest through its subsidiaries, Syngas International Corp. and Syngas Energy Corp., is an emerging leader in the development and marketing of low-cost alternate fuels worldwide. Through its technology, the company is focused on becoming a "GreenPowerhouse". Record energy prices combined with the global focus moving rapidly towards addressing pollution, has heightened the need for sustainable, zero emission energy. Energy Quest's technology is based on clean renewable energy positioning it to benefit from global trends.

References:
MarketWire: Energy Quest Signs Letter of Intent With Etanol del Pacifico Sur S.A. - March 3, 2008.

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New study shows way to fourth-generation biofuels: scientists uncover mechanism that regulates carbon dioxide fixation in plants

A team of Biotechnology and Biological Sciences Research Council (BBSRC) funded scientists at the University of Essex has discovered a new mechanism that slows the process of carbon dioxide fixation in plants. The research, to be published today in the Proceedings of the National Academy of Sciences, may ultimately lead to dramatic crop improvements and, they say, "fourth generation" biofuels that remove CO2 from the atmosphere. The scientists reveil a crucial mechanism of the Calvin cycle, which regulates the way plants deal with the ultimate variable: the amount of sunshine they receive.

From first to fourth generation fuels
Biofuel development is currently undergoing a transition from first to second generation fuels that can be made from any biomass source. But scientists are already going beyond the new generation and are thinking of terms of a third, and even fourth-generation (overview in this previous post).

The first generation of biofuels was based on utilizing easily extractible sugars, starches and oils. These carbohydrates and triglycerides come in the form of food: sugar from beets or sugarcane, grains like wheat and maize, or oil from rapeseed or oil palms. These fuels have received their fair deal of criticism, because the perception is that their production is a factor in increased food prices.

A far more sustainable way to make biofuels is to use biochemical and thermochemical conversion methods to turn lignocellulosic biomass into fuels. Some of these techniques, such as gasification and synthesis via the Fischer-Tropsch process are already competitive with oil at over $65. Others are receiving a lot of research attention. If these conversion technologies become cost-competitive and efficient, then the food versus fuel debate is set to end. Lignin and cellulose are the most abundant organic polymers on Earth.

Now a third-generation of biofuels goes a step further: it is based on dedicated crops the properties of which have been designed in such a way that they conform to a particular conversion process. An example would be maize which grows its own cellulase enzymes (previous post), or trees and crops with less lignin which means more cellulose can be converted (more here). These crops have already been developed and many more are under investigation.

The most radical and futuristic biofuels add a component to the production process: the production process is coupled to carbon capture and storage techniques, which allows for the production of carbon-negative bioenergy (contrary to the previous generations, which are merely 'carbon neutral'). In practise this means a transition to a decarbonised biofuel better known as bio-hydrogen the CO2 of which has been captured. Alternatively and perhaps more feasible is a transition to electric transport based on carbon-negative bio-electricity, generated from fourth generation biomass systems.

Crucial to make this transition more efficient is the development of crops that sequester more CO2 than normal plants. Such high-carbon plants withdraw the greenhouse gas from the atmosphere and use it to grow more lignocellulose. When during their conversion into biohydrogen (or bio-electricity) more CO2 is captured and stored, it means they become more carbon-negative. The first crops with a higher CO2 storing capacity have meanwhile been developed: an eucalyptus tree that stores more CO2 and grows less ligning but more cellulose (previous post), and a hybrid larch that sequesters up to 30% more CO2 (earlier post).

The strange world of carbon-negative bioenergy means that more one were to use these fuels in a car, the more one would be fighting climate change: driving more would be good for the planet and help end global warming (previous post). Contrary to other renewables like solar or wind power, which only yield "carbon neutral" energy, carbon-negative biofuels actively remove CO2 from the past from the atmosphere. They generate "negative emissions". Thus they are the most radical tool in the climate fight.

Cracking the Calvin cycle
In a finding that further paves the way for these fourth-generation biofuels and dramatic crop improvements, the scientists from Essex have discovered the mechanism which helps to regulate the way in which plants absorb CO2 from the atmosphere and turn it into sugars.

Plants are dependent on sunlight to capture carbon dioxide, which is turned into important sugars via a process called the Calvin cycle (schematic, click to enlarge). As a result, as the amount of sunlight varies during the day (e.g. through cloud cover or shading from other plants), they must also be able to vary the speed at which they capture carbon dioxide from the atmosphere. This ensures that when there is a lot of sunlight, it is taken full advantage of but that when sunlight drops, so does CO2 uptake. This ability to maximise energy use is important for plants and prevents the loss of important metabolic resources. Because they essentially stay in one place, plants must have many unique abilities to adapt to their environment as it changes around them.

Scientists have been trying to find out how this variable speed control actually works. For the first time they now show how the Calvin cycle can be regulated in response to a changing light environment via a molecular mechanism. There is a special relationship between two enzymes that are involved in the Calvin cycle: phosphoribulokinase (PRK) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH):
energy :: sustainability :: biomass :: bioenergy :: biofuels :: lignocellulose :: carbon dioxide :: Calvin cycle :: plant biology :: efficiency :: carbon-negative :: climate change ::

When light levels decrease, the two enzymes tend to stick together and therefore cannot function, thus slowing the Calvin cycle. The darker it is, the more PRK-GAPDH partnerships are formed and the slower the Calvin cycle becomes. In the light, they break apart rapidly and the Calvin cycle is allowed to speed up.

This fundamental research has thus revealed a novel mechanism and provides a better understanding of the regulation of CO2 fixation in plants. This work will underpin strategies to increase the amount of carbon dioxide absorbed by plants thereby increasing yield for food and biofuel production, and may ultimately feed into the development of "fourth generation" biofuels.

Although this research focuses on the fundamental biological processes that plants use, ultimately, if we can understand these processes, we can use the knowledge to develop and improve food and biofuel crops. - Professor Christine Raines of the University of Essex, Research Leader

Dr Tom Howard, who contributed to the research, added that plants have evolved a fascinating way to cope with variations in their local environments. Unlike animals, they cannot move on to look for new food sources. This research helps to unlock one way that plants deal with the ultimate variable: the amount of sunshine they receive.

References:
Thomas P. Howard, Metodi Metodiev, Julie C. Lloyd, and Christine A. Raines, "Thioredoxin-mediated reversible dissociation of a stromal multiprotein complex in response to changes in light availability", PNAS, March 4 early edition [no link available at the time of publishing; check back later today].

Eurekalert: Scientists uncover a novel mechanism that regulates carbon dioxide fixation in plants - March 4, 2008.

Biopact: A quick look at 'fourth generation' biofuels - October 08, 2007

Biopact: Japanese scientists develop hybrid larch trees with 30% greater carbon sink capacity - October 03, 2007

Biopact: Scientists develop low-lignin eucalyptus trees that store more CO2, provide more cellulose for biofuels - September 17, 2007

Biopact: Third generation biofuels: scientists patent corn variety with embedded cellulase enzymes - May 05, 2007

Biopact: Scientists release new low-lignin sorghums: ideal for biofuel and feed - September 10, 2007

Biopact: The strange world of carbon-negative bioenergy: the more you drive your car, the more you tackle climate change - October 29, 2007

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Researchers discover key to bacterial bio-electricity production

Researchers at the University of Minnesota studying bacteria capable of generating electricity have discovered that riboflavin, commonly known as vitamin B-2, is responsible for much of the energy produced by these organisms. The bacteria, Shewanella, are commonly found in water and soil and are of interest because they can convert simple organic compounds such as lactic acid into electricity. The discovery means the development of efficient bio-fuel cells, or microbial fuel cells (MFCs), comes a step closer. Findings are published in the March 3 issue of Proceedings of the National Academy of Sciences.

The discovery means Shewanella can produce more power simply by increased riboflavin levels. Also, the finding opens up multiple possibilities for innovations in renewable energy - the production of clean power from biomass - and for environmental clean-up.

This is very exciting because it solves a fundamental biological puzzle. Scientists have known for years that Shewanella produce electricity. Now we know how they do it. - Daniel Bond, University of Minnesota's BioTechnology Institute

The interdisciplinary research team, which included several students, showed that bacteria growing on electrodes naturally produced riboflavin. Because riboflavin was able to carry electrons from the living cells to the electrodes, rates of electricity production increased by 370 percent as riboflavin accumulated.

Scaled-up MFCs using similar bacteria could generate enough electricity to clean up wastewater or power remote sensors on the ocean floor. Bacteria could help pay the bills for a wastewater treatment plant. But more ambitious applications, such as electricity for transportation, homes or businesses, will require significant advances in biology and in the cost-effectiveness of fuel cell materials. (An overview of recent developments in MFCs and their potential applications can be found here).

Why do these bacteria produce electricity? In nature, bacteria such as Shewanella need to access and dissolve metals such as iron. Having the ability to direct electrons to metals (schematic, click to enlarge) allows them to change their chemistry and availability:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: sugars :: microbial fuel cell :: bio-fuel cell :: bacteria :: microbiology :: biochemistry ::

Bacteria have been changing the chemistry of the environment for billions of years. Their ability to make iron soluble is key to metal cycling in the environment and essential to most life on earth. - Jeffrey Gralnick, University of Minnesota's department of microbiology

The process could be reversed to prevent corrosion of iron and other metals on ships. Bond and Gralnick were each recently awarded funding from the U.S. Navy to explore this and other potential applications.

These electrochemical and analytical observations demonstrate that biofilms of Shewanella use secreted flavins in electron transfer to external acceptors, and that many environmentally relevant surfaces exposed to Shewanella are coated by electroactive flavins that may affect interactions with bacterial surface proteins. In metal-containing environments, flavin electron shuttling, metal chelation, and surface binding could act in concert to promote respiration and metal oxide dissolution phenotypes associated with this organism. Many activities catalyzed by Shewanella, and other organisms that secrete electroactive compounds, should be reexamined in light of this complex and ecologically important behavior. - Bond et. al.

This research was funded by the Initiative for Renewable Energy and the Environment, the National Science Foundation, the National Institutes of Health and Cargill.

The university's BioTechnology Institute is co-sponsored by the College of Biological Sciences and the Institute of Technology.

References:
Enrico Marsili, Daniel B. Baron, Indraneel D. Shikhare, Dan Coursolle, Jeffrey A. Gralnick, and Daniel R. Bond, "Shewanella secretes flavins that mediate extracellular electron transfer" [*.pdf], PNAS published March 3, 2008, 10.1073/pnas.0710525105

University of Minnessota: U of M researchers discover key for converting waste to electricity - March 3, 2008.

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