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    Vietnam has won the prestigious EU-sponsored Energy Globe award for 2006 for a community biogas program, the Ministry of Agriculture and Rural Development announced. ThanhNien News - April 13, 2007.

    Given unstable fossil fuel prices and their negative effects on the economy, Tanzania envisages large-scale agriculture of energy crops Deputy Minister for Agriculture, Food Security and Cooperatives, Mr Christopher Chiza has said. A 600 hectare jatropha seed production effort is underway, with the seeds expected to be distributed to farmers during the 2009/2010 growing season. Daily News (Dar es Salaam) - April 12, 2007.

    Renault has announced it will launch a flex-fuel version of its Logan in Brazil in July. Brazilian autosales rose 28% to 1,834,581 in 2006 from 2004. GreenCarCongress - April 12, 2007.

    Chevron and Weyerhouser, one of the largest forest products companies, are joining forces to research next generation biofuels. The companies will focus on developing technology that can transform wood fiber and other nonfood sources of cellulose into economical, clean-burning biofuels for cars and trucks. PRNewswire - April 12, 2007.

    BioConversion Blog's C. Scott Miller discusses the publication of 'The BioTown Source Book', which offers a very accessible introduction to the many different bioconversion technologies currently driving the bioenergy sector. BioConversion Blog - April 11, 2007.

    China's State Forestry Administration (SFA) and the China National Cereals, Oils and Foodstuffs Import & Export Corp., Ltd. (COFCO) have signed a framework agreement over plans to cooperatively develop forest bioenergy resources, COFCO announced on its web site. Interfax China - April 11, 2007.

    The Ministry of Agriculture and Livestock of El Salvador is speeding up writing the country's biofuels law in order to take advantage of the US-Brazil cooperation agreement which identified the country as one where projects can be launched fairly quickly. The bill is expected to be presented to parliament in the coming weeks. El Porvenir - April 11, 2007.

    ConocoPhillips will establish an eight-year, $22.5 million research program at Iowa State University dedicated to developing technologies that produce biofuels. The grant is part of ConocoPhillips' plan to create joint research programs with major universities to produce viable solutions to diversify America's energy sources. Iowa State University - April 11, 2007.

    Interstate Power and Light has decided to utilize super-critical pulverized coal boiler technology at its large (600MW) new generation facility planned for Marshalltown, Iowa. The plant is designed to co-fire biomass and has a cogeneration component. The investment tops US$1billion. PRNewswire - April 10, 2007.

    One of India's largest sugar companies, the Birla group will invest 8 billion rupees (US$187 million) to expand sugar and biofuel ethanol output and produce renewable electricity from bagasse, to generate more revenue streams from its sugar business. Reuters India - April 9, 2007.

    An Iranian firm, Mashal Khazar Darya, is to build a cellulosic ethanol plant that will utilise switchgrass as its feedstock at a site it owns in Bosnia-Herzegovina. The investment is estimated to be worth €112/US$150 million. The plant's capacity will be 378 million liters (100 million gallons), supplied by switchgrass grown on 4400 hectares of land. PressTv (Iran) - April 9, 2007.

    The Africa Power & Electricity Congress and Exhibition, to take place from 16 - 20 April 2007, in the Sandton Convention Centre, Johannesburg, South Africa, will focus on bioenergy and biofuels. The Statesman - April 7, 2007.

    Petrobras and Petroecuador have signed a joint performance MOU for a technical, economic and legal viability study to develop joint projects in biofuel production and distribution in Ecuador. The project includes possible joint Petroecuador and Petrobras investments, in addition to qualifying the Ecuadorian staff that is directly involved in biofuel-related activities with the exchange of professionals and technical training. PetroBras - April 5, 2007.

    The Société de Transport de Montréal is to buy 8 biodiesel-electric hybrid buses that will use 20% less fuel and cut 330 tons of GHG emissions per annum. Courrier Ahuntsic - April 3, 2007.

    Thailand mandates B2, a mixture of 2% biodiesel and 98% diesel. According to Energy Minister Piyasvasti Amranand, the mandate comes into effect by April next year. Bangkok Post - April 3, 2007.

    In what is described as a defeat for the Bush administration, the U.S. Supreme Court ruled [*.pdf] today that environmental officials have the power to regulate greenhouse gas emissions that spur global warming. By a 5-4 vote, the nation's highest court told the U.S. Environmental Protection Agency to reconsider its refusal to regulate carbon dioxide and other emissions from new cars and trucks that contribute to climate change. Reuters - April 2, 2007.

    Goldman Sachs estimates that, in the absence of current trade barriers, Latin America could supply all the ethanol required in the US and Europe at a cost of $45 per barrel – just over half the cost of US-made ethanol. EuroToday - April 2, 2007.

    The Kauai Island Utility Cooperative signed a long-term purchase power agreement last week with Green Energy Team, LLC. The 20-year agreement enables KIUC to purchase power from Green Energy's proposed 6.4 megawatt biomass-to-energy facility, which will use agricultural waste to generate power. Honolulu Advertiser - April 2, 2007.

    The market trend to heavier, more powerful hybrids is eroding the fuel consumption advantage of hybrid technology, according to a study done by researchers at the University of British Columbia. GreenCarCongress - March 30, 2007.

    Hungarian privately-owned bio-ethanol project firm Mabio is planning to complete an €80-85 million ethanol plant in Southeast Hungary's Csabacsud by end-2008. Onet/Interfax - March 29, 2007.

    Energy and engineering group Abengoa announces it has applied for planning permission to build a bioethanol plant in north-east England with a capacity of about 400,000 tonnes a year. Reuters - March 29, 2007.

    The second European Summer School on Renewable Motor Fuels will be held in Warsaw, Poland, from 29 to 31 August 2007. The goal of the event is to disseminate the knowledge generated within the EU-funded RENEW (Renewable Fuels for Advanced Powertrains) project and present it to the European academic audience and stakeholders. Topics on the agenda include generation of synthetic gas from biomass and gas cleaning; transport fuel synthesis from synthetic gas; biofuel use in different motors; biomass potentials, supply and logistics, and technology, cost and life-cycle assessment of BtL pathways. Cordis News - March 27, 2007.

    Green Swedes want even more renewables, according to a study from Gothenburg University. Support for hydroelectricity and biofuels has increased, whereas three-quarters of people want Sweden to concentrate more on wind and solar too. Swedes still back the nuclear phase-out plans. The country is Europe's largest ethanol user. It imports 75% of the biofuel from Brazil. Sveriges Radio International - March 27, 2007.

    Fiat will launch its Brazilian-built flex-fuel Uno in South Africa later this year. The flex-fuel Uno, which can run on gasoline, ethanol or any combination of the two fuels, was displayed at the Durban Auto Show, and is set to become popular as South Africa enters the ethanol era. Automotive World - March 27, 2007.

    Siemens Power Generation (PG) is to supply two steam turbine gensets to a biomass-fired plant in Três Lagoas, 600 kilometers northwest of São Paulo. The order, valued at €22 million, was placed by the Brazilian company Pöyry Empreendimentos, part of VCP (Votorantim Celulose e Papel), one of the biggest cellulose producers in the Americas. PRDomain - March 25, 2007.

    Asia’s demand for oil will nearly double over the next 25 years and will account for 85% of the increased demand in 2007, Organization of Petroleum Exporting Countries (Opec) officials forecast yesterday at a Bangkok-hosted energy conference. Daily Times - March 24, 2007.

    Portugal's government expects total investment in biomass energy will reach €500 million in 2012, when its target of 250MW capacity is reached. By that date, biomass will reduce 700,000 tonnes of carbon emissions. By 2010, biomass will represent 5% of the country's energy production. Forbes - March 22, 2007.

    The Scottish Executive has announced a biomass action plan for Scotland, through which dozens of green energy projects across the region are set to benefit from an additional £3 million of funding. The plan includes greater use of the forestry and agriculture sectors, together with grant support to encourage greater use of biomass products. Energy Business Review Online - March 21, 2007.

    The U.S. Dep't of Agriculture's Forest Service has selected 26 small businesses and community groups to receive US$6.2 million in grants from for the development of innovative uses for woody biomass. American Agriculturalist - March 21, 2007.

    Three universities, a government laboratory, and several companies are joining forces in Colorado to create what organizers hope will be a major player in the emerging field of converting biomass into fuels and other products. The Colorado Center for Biorefining & Biofuels, or C2B2, combines the biofuels and biorefining expertise of the University of Colorado, Colorado State University, the Colorado School of Mines, and the Colorado-based National Renewable Energy Laboratory (NREL). Founding corporate members include Dow Chemical, Chevron, ConocoPhillips, and Shell. C&EN - March 20, 2007.

    The city of Rome has announced plans to run its public bus fleet on a fuel mix of 20 per cent biodiesel. The city council has signed an accord that would see its 2800 buses switch to the blended fuel in order to cut greenhouse gas emissions and local air pollution. A trial of 200 buses, if successful, would see the entire fleet running on the biofuel mix by the end of 2008. Estimates put the annual emission savings at 40,000 tonnes of carbon dioxide. CarbonPositive - March 19, 2007.

    CODON (Dutch Biotech Study Association) organises a symposium on the 'Biobased Economy' in Wageningen, Netherlands, home of one of Europe's largest agricultural universities. In a biobased economy, chemistry companies and other non-food enterprises primarily use renewable materials and biomass as their resources, instead of petroleum. The Netherlands has the ambition to have 30% of all used materials biobased, by 2030. FoodHolland - March 19, 2007.

    Energy giants BP and China National Petroleum Corp, the PRC's biggest oil producer, are among the companies that are in talks with Guangxi Xintiande Energy Co about buying a stake in the southern China ethanol producer to expand output. Xintiande Energy currently produces ethanol from cassava. ChinaDaily - March 16, 2007.

    Researchers at eTEC Business Development Ltd., a biofuels research company based in Vienna, Austria, have devised mobile facilities that successfully convert the biodiesel by-product glycerin into electricity. The facilities, according to researchers, will provide substantial economic growth for biodiesel plants while turning glycerin into productive renewable energy. Biodiesel Magazine - March 16, 2007.

    Ethanol Africa, which plans to build eight biofuel plants in the maize belt, has secured funding of €83/US$110 million (825 million Rand) for the first facility in Bothaville, its principal shareholder announced. Business Report - March 16, 2007.

    A joint venture between Energias de Portugal SGPS and Altri SGPS will be awarded licences to build five 100 MW biomass power stations in Portugal's eastern Castelo Branco region. EDP's EDP Bioelectrica unit and Altri's Celulose de Caima plan to fuel the power stations with forestry waste material. Total investment on the programme is projected at €250/US$333 million with 800 jobs being created. Forbes - March 16, 2007.

    Indian bioprocess engineering firm Praj wins €11/US$14.5 million contract for the construction of the wheat and beet based bio-ethanol plant for Biowanze SA in Belgium, a subsidiary of CropEnergies AG (a Sudzucker Group Company). The plant has an ethanol production capacity of 300,000 tons per year. IndiaPRWire - March 15, 2007.

    Shimadzu Scientific Instruments announced the availability of its new white paper, “Overview of Biofuels and the Analytical Processes Used in their Manufacture.” The paper is available for free download at the company’s website. The paper offers an overview of the rapidly expanding global biofuel market with specific focus on ethanol and biodiesel used in auto transportation. It provides context for these products within the fuel market and explains raw materials and manufacturing. Most important, the paper describes the analytical processes and equipment used for QA testing of raw materials, in-process materials, and end products. BusinessWire - March 15, 2007.

    Côte d'Ivoire's agriculture minister Amadou Gon has visited the biofuels section of the Salon de l'Agriculture in Paris, one of the largest fairs of its kind. According to his communication office, the minister is looking into drafting a plan for the introduction of biofuels in the West African country. AllAfrica [*French] - March 13, 2007.


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Friday, April 13, 2007

Scientists reveal quantum secrets of photosynthesis - may lead to clean energy

While astrobiologists speculate on what plants on planets in other solar systems might look like (not green) and reveal clues on how to make photosynthesis more efficient, science is still trying to unravel some of the long-standing mysteries of how the mechanism works here on Earth. Researchers with the the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) at Berkeley, have now come a step closer to understanding it. Speed is the key to the transfer of sunlight energy to molecular reaction centers for conversion into chemical energy with nearly 100-percent efficiency. The transfer of the solar energy takes place almost instantaneously, so little energy is wasted as heat. But how photosynthesis actually achieves this near instantaneous energy transfer has remained a secret.

The team of researchers reports that the answer lies in quantum mechanical effects. Results of its study are presented in the April 12, 2007 issue of the journal Nature. Their discovery may ultimately lead to the creation of artificial photosynthesis that would allow us to tap into the sun as a clean, efficient, sustainable and carbon-neutral source of energy.
“We have obtained the first direct evidence that remarkably long-lived wavelike electronic quantum coherence plays an important part in energy transfer processes during photosynthesis. This wavelike characteristic can explain the extreme efficiency of the energy transfer because it enables the system to simultaneously sample all the potential energy pathways and choose the most efficient one.” - Graham Fleming, Deputy Director of Berkeley Lab, a professor of chemistry at UC Berkeley.
Graham Fleming is the lead author of the study and an internationally acclaimed leader in spectroscopic studies of the photosynthetic process. In a paper entitled "Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems", he and his collaborators report the detection of “quantum beating” signals, coherent electronic oscillations in both donor and acceptor molecules, generated by light-induced energy excitations, like the ripples formed when stones are tossed into a pond (image, click to enlarge).

Electronic spectroscopy measurements made on a femtosecond (millionths of a billionth of a second) time-scale showed these oscillations meeting and interfering constructively, forming wavelike motions of energy ('superposition states') that can explore all potential energy pathways simultaneously and reversibly, meaning they can retreat from wrong pathways with no penalty. This finding contradicts the classical description of the photosynthetic energy transfer process as one in which excitation energy hops from light-capturing pigment molecules to reaction center molecules step-by-step down the molecular energy ladder.

“The classical hopping description of the energy transfer process is both inadequate and inaccurate,” said Fleming. “It gives the wrong picture of how the process actually works, and misses a crucial aspect of the reason for the wonderful efficiency", the professor added:
:: :: :: :: :: :: :: :: :: ::

The photosynthetic technique for transferring energy from one molecular system to another should make any short-list of Mother Nature’s spectacular accomplishments. If we can learn enough to emulate this process, we might be able to create artificial versions of photosynthesis that would help us effectively tap into the sun as a clean, efficient, sustainable and carbon-neutral source of energy.

Towards this end, Fleming and his research group have developed a technique called two-dimensional electronic spectroscopy that enables them to follow the flow of light-induced excitation energy through molecular complexes with femtosecond temporal resolution. The technique involves sequentially flashing a sample with femtosecond pulses of light from three laser beams. A fourth beam is used as a local oscillator to amplify and detect the resulting spectroscopic signals as the excitation energy from the laser lights is transferred from one molecule to the next. (The excitation energy changes the way each molecule absorbs and emits light.)

Fleming has compared 2-D electronic spectroscopy to the technique used in the early super-heterodyne radios, where an incoming high frequency radio signal was converted by an oscillator to a lower frequency for more controllable amplification and better reception (image, click to enlarge). In the case of 2-D electronic spectroscopy, scientists can track the transfer of energy between molecules that are coupled (connected) through their electronic and vibrational states in any photoactive system, macromolecular assembly or nanostructure.

Fleming and his group first described 2-D electronic spectroscopy in a 2005 Nature paper, when they used the technique to observe electronic couplings in the Fenna-Matthews-Olson (FMO) photosynthetic light-harvesting protein, a molecular complex in green sulphur bacteria.

Gregory Engel, first author of the study said: “The 2005 paper was the first biological application of this technique, now we have used 2-D electronic spectroscopy to discover a new phenomenon in photosynthetic systems. While the possibility that photosynthetic energy transfer might involve quantum oscillations was first suggested more than 70 years ago, the wavelike motion of excitation energy had never been observed until now.”

As in the 2005 paper, the FMO protein was again the target. FMO is considered a model system for studying photosynthetic energy transfer because it consists of only seven pigment molecules and its chemistry has been well characterized.

“To observe the quantum beats, 2-D spectra were taken at 33 population times, ranging from 0 to 660 femtoseconds,” said Engel. “In these spectra, the lowest-energy exciton (a bound electron-hole pair formed when an incoming photon boosts an electron out of the valence energy band into the conduction band) gives rise to a diagonal peak near 825 nanometers that clearly oscillates. The associated cross-peak amplitude also appears to oscillate. Surprisingly, this quantum beating lasted the entire 660 femtoseconds.”

Engel said the duration of the quantum beating signals was unexpected because the general scientific assumption had been that the electronic coherences responsible for such oscillations are rapidly destroyed.

“For this reason, the transfer of electronic coherence between excitons during relaxation has usually been ignored,” Engel said. “By demonstrating that the energy transfer process does involve electronic coherence and that this coherence is much stronger than we would ever have expected, we have shown that the process can be much more efficient than the classical view could explain. However, we still don’t know to what degree photosynthesis benefits from these quantum effects.”

Engel said one of the next steps for the Fleming group in this line of research will be to look at the effects of temperature changes on the photosynthetic energy transfer process. The results for this latest paper in Nature were obtained from FMO complexes kept at 77 Kelvin. The group will also be looking at broader bandwidths of energy using different colors of light pulses to map out everything that is going on, not just energy transfer. Ultimately, the idea is to gain a much better understanding how nature not only transfers energy from one molecular system to another, but is also able to convert it into useful forms.

“Nature has had about 2.7 billion years to perfect photosynthesis, so there are huge lessons that remain for us to learn,” Engel said. “The results we’re reporting in this latest paper, however, at least give us a new way to think about the design of future artificial photosynthesis systems.”

This research was funded by the U.S. Department of Energy and by the Miller Institute for Basic Research in Sciences.

Co-authoring the Nature paper with Fleming were Gregory Engel, who was first author, Tessa Calhoun, Elizabeth Read, Tae-Kyu Ahn, Tomáš Mančal and Yuan-Chung Cheng, all of whom held joint appointments with Berkeley Lab’s Physical Biosciences Division and the UC Berkeley Chemistry Department at the time of the study, plus Robert Blankenship, from the Washington University in St. Louis.

More information:

Nature, Editor's Summary: Making photosynthesis tick - 12 April 2007

Tobias Brixner, Jens Stenger, Harsha M. Vaswani, Minhaeng Cho, Robert E. Blankenship and Graham R. Fleming, "Two-dimensional spectroscopy of electronic couplings in photosynthesis" [*abstract], Nature 434, 625-628 (31 March 2005) | doi:10.1038/nature03429

Gregory S. Engel, Tessa R. Calhoun, Elizabeth L. Read, Tae-Kyu Ahn, Tomás caron Manc caronal, Yuan-Chung Cheng, Robert E. Blankenship & Graham R. Fleming, "Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems", [*abstract], Nature, 446 Number 7137 pp701-830434, 625-628 (12 April 2007) | doi:10.1038/446740a


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