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    Japan's Tsukishima Kikai Co. and Marubeni Corp. have together clinched an order from Oenon Holdings Inc. for a plant that will make bioethanol from rice. The Oenon group will invest around 4.4 billion yen (US$40.17 million) in the project, half of which will be covered by a subsidy from the Ministry of Agriculture, Forestry and Fisheries. The plant will initially produce bioethanol from imported rice, with plans to use Hokkaido-grown rice in the future. It will produce 5 million liters per year starting in 2009, increasing output to 15m liters in 2011. The facility will be able to produce as much as 50,000 liters of bioethanol from 125 tons of rice each day. Trading Markets - January 11, 2007.

    PetroSun, Inc. announced today that its subsidiary, PetroSun BioFuels Refining, has entered into a JV to construct and operate a biodiesel refinery near Coolidge, Arizona. The feedstock for the refinery will be algal oil produced by PetroSun BioFuels at algae farms to be located in Arizona. The refinery will have a capacity of thirty million gallons and will produce 100% renewable biodiesel. PetroSun BioFuels will process the residual algae biomass into ethanol. MarketWire - January 10, 2007.

    BlueFire Ethanol Fuels Inc, which develops and operates carbohydrate-based transportation fuel production facilities, has secured capital liquidity for corporate overhead and continued project development in the value of US$15 million with Quercus, an environmentally focused trust. BlueFire Ethanol Fuels - January 09, 2007.

    Some $170 billion in new technology development projects, infrastructure equipment and construction, and biofuel refineries will result from the ethanol production standards contained the new U.S. Energy Bill, says BIO, the global Biotechnology Industry Organization. According to Brent Erickson, BIO's executive vice president "Such a new energy infrastructure has not occurred in more than 100 years. We are at the point where we were in the 1850s when kerosene was first distilled and began to replace whale oil. This technology will be coming so fast that what we say today won't be true in two years." Chemical & Engineering News - January 07, 2007.

    Scottish and Southern Energy plc, the UK's second largest power company, has completed the acquisition of Slough Heat and Power Ltd from SEGRO plc for a total cash consideration of £49.25m. The 101MW CHP plant is the UK’s largest dedicated biomass energy facility fueled by wood chips, biomass and waste paper. Part of the plant is contracted under the Non Fossil Fuel Obligation and part of it produces over 200GWH of output qualifying for Renewable Obligation Certificates (ROCs), which is equivalent to around 90MW of wind generation. Scottish & Southern Energy - January 2, 2007.

    PetroChina Co Ltd, the country's largest oil and gas producer, plans to invest 800 million yuan to build an ethanol plant in Nanchong, in the southwestern province of Sichuan, its parent China National Petroleum Corp said. The ethanol plant has a designed annual capacity of 100,000 tons. ABCMoneyNews - December 21, 2007.

    Mexico passed legislation to promote biofuels last week, offering unspecified support to farmers that grow crops for the production of any renewable fuel. Agriculture Minister Alberto Cardenas said Mexico could expand biodiesel faster than ethanol. More soon. Reuters - December 20, 2007.

    Oxford Catalysts has placed an order worth approximately €700,000 (US$1 million) with the German company Amtec for the purchase of two Spider16 high throughput screening reactors. The first will be used to speed up the development of catalysts for hydrodesulphurisation (HDS). The second will be used to further the development of catalysts for use in gas to liquid (GTL) and Fischer-Tropsch processes which can be applied to next generation biofuels. AlphaGalileo - December 18, 2007.

    According to the Instituto Brasileiro de Geografia e Estatística (IBGE), Brazil's production of sugarcane will increase from 514,1 million tonnes this season, to a record 561,8 million tonnes in the 2008/09 cyclus - an increase of 9.3%. New numbers are also out for the 2007 harvest in Brazil's main sugarcane growing region, the Central-South: a record 425 million tonnes compared to 372,7 million tonnes in 2006, or a 14% increase. The estimate was provided by Unica – the União da Indústria de Cana-de-Açúcar. Jornal Cana - December 16, 2007.

    The University of East Anglia and the UK Met Office's Hadley Centre have today released preliminary global temperature figures for 2007, which show the top 11 warmest years all occurring in the last 13 years. The provisional global figure for 2007 using data from January to November, currently places the year as the seventh warmest on records dating back to 1850. The announcement comes as the Secretary-General of the World Meteorological Organization (WMO), Michel Jarraud, speaks at the Conference of the Parties (COP) in Bali. Eurekalert - December 13, 2007.

    The Royal Society of Chemistry has announced it will launch a new journal in summer 2008, Energy & Environmental Science, which will distinctly address both energy and environmental issues. In recognition of the importance of research in this subject, and the need for knowledge transfer between scientists throughout the world, from launch the RSC will make issues of Energy & Environmental Science available free of charge to readers via its website, for the first 18 months of publication. This journal will highlight the important role that the chemical sciences have in solving the energy problems we are facing today. It will link all aspects of energy and the environment by publishing research relating to energy conversion and storage, alternative fuel technologies, and environmental science. AlphaGalileo - December 10, 2007.

    Dutch researcher Bas Bougie has developed a laser system to investigate soot development in diesel engines. Small soot particles are not retained by a soot filter but are, however, more harmful than larger soot particles. Therefore, soot development needs to be tackled at the source. Laser Induced Incandescence is a technique that reveals exactly where soot is generated and can be used by project partners to develop cleaner diesel engines. Terry Meyer, an Iowa State University assistant professor of mechanical engineering, is using similar laser technology to develop advanced sensors capable of screening the combustion behavior and soot characteristics specifically of biofuels. Eurekalert - December 7, 2007.

    Lithuania's first dedicated biofuel terminal has started operating in Klaipeda port. At the end of November 2007, the stevedoring company Vakaru krova (VK) started activities to manage transshipments. The infrastructure of the biodiesel complex allows for storage of up to 4000 cubic meters of products. During the first year, the terminal plans to transship about 70.000 tonnes of methyl ether, after that the capacities of the terminal would be increased. Investments to the project totaled €2.3 million. Agrimarket - December 5, 2007.

    New Holland supports the use of B100 biodiesel in all equipment with New Holland-manufactured diesel engines, including electronic injection engines with common rail technology. Overall, nearly 80 percent of the tractor and equipment manufacturer's New Holland-branded products with diesel engines are now available to operate on B100 biodiesel. Tractor and equipment maker John Deere meanwhile clarified its position for customers that want to use biodiesel blends up to B20. Grainnet - December 5, 2007.

    According to Wetlands International, an NGO, the Kyoto Protocol as it currently stands does not take into account possible emissions from palm oil grown on a particular type of land found in Indonesia and Malaysia, namely peatlands. Mongabay - December 5, 2007.

    Malaysia's oil & gas giant Petronas considers entering the biofuels sector. Zamri Jusoh, senior manager of Petronas' petroleum development management unit told reporters "of course our focus is on oil and gas, but I think as we move into the future we cannot ignore the importance of biofuels." AFP - December 5, 2007.

    In just four months, the use of biodiesel in the transport sector has substantially improved air quality in Metro Manila, data from the Philippines Department of Environment and Natural Resources (DENR) showed. A blend of one percent coco-biodiesel is mandated by the Biofuels Act of 2007 which took effect last May. By 2009, it would be increased to two percent. Philippine Star - December 4, 2007.

    Kazakhstan will next year adopt laws to regulate its fledgling biofuel industry and plans to construct at least two more plants in the next 18 months to produce environmentally friendly fuel from crops, industry officials said. According to Akylbek Kurishbayev, vice-minister for agriculture, he Central Asian country has the potential to produce 300,000 tons a year of biodiesel and export half. Kazakhstan could also produce up to 1 billion liters of bioethanol, he said. "The potential is huge. If we use this potential wisely, we can become one of the world's top five producers of biofuels," Beisen Donenov, executive director of the Kazakhstan Biofuels Association, said on the sidelines of a grains forum. Reuters - November 30, 2007.

    SRI Consulting released a report on chemicals from biomass. The analysis highlights six major contributing sources of green and renewable chemicals: increasing production of biofuels will yield increasing amounts of biofuels by-products; partial decomposition of certain biomass fractions can yield organic chemicals or feedstocks for the manufacture of various chemicals; forestry has been and will continue to be a source of pine chemicals; evolving fermentation technology and new substrates will also produce an increasing number of chemicals. Chemical Online - November 27, 2007.

    German industrial conglomerate MAN AG plans to expand into renewable energies such as biofuels and solar power. Chief Executive Hakan Samuelsson said services unit Ferrostaal would lead the expansion. Reuters - November 24, 2007.

    Analysts think Vancouver-based Ballard Power Systems, which pumped hundreds of millions and decades of research into developing hydrogen fuel cells for cars, is going to sell its automotive division. Experts describe the development as "the death of the hydrogen highway". The problems with H2 fuel cell cars are manifold: hydrogen is a mere energy carrier and its production requires a primary energy input; production is expensive, as would be storage and distribution; finally, scaling fuel cells and storage tanks down to fit in cars remains a huge challenge. Meanwhile, critics have said that the primary energy for hydrogen can better be used for electricity and electric vehicles. On a well-to-wheel basis, the cleanest and most efficient way to produce hydrogen is via biomass, so the news is a set-back for the biohydrogen community. But then again, biomass can be used more efficiently as electricity for battery cars. Canada.com - November 21, 2007.

    South Korea plans to invest 20 billion won (€14.8/$21.8 million) by 2010 on securing technologies to develop synthetic fuels from biomass, coal and natural gas, as well as biobutanol. 29 private companies, research institutes and universities will join this first stage of the "next-generation clean energy development project" led by South Korea's Ministry of Commerce, Industry and Energy. Korea Times - November 19, 2007.

    OPEC leaders began a summit today with Venezuelan President Hugo Chavez issuing a chilling warning that crude prices could double to US$200 from their already-record level if the United States attacked Iran or Venezuela. He urged assembled leaders from the OPEC, meeting for only the third time in the cartel's 47-year history, to club together for geopolitical reasons. But the cartel is split between an 'anti-US' block including Venezuela, Iran, and soon to return ex-member Ecuador, and a 'neutral' group comprising most Gulf States. France24 - November 17, 2007.

    The article "Biofuels: What a Biopact between North and South could achieve" published in the scientific journal Energy Policy (Volume 35, Issue 7, 1 July 2007, Pages 3550-3570) ranks number 1 in the 'Top 25 hottest articles'. The article was written by professor John A. Mathews, Macquarie University (Sydney, Autralia), and presents a case for a win-win bioenergy relationship between the industrialised and the developing world. Mathews holds the Chair of Strategic Management at the university, and is a leading expert in the analysis of the evolution and emergence of disruptive technologies and their global strategic management. ScienceDirect - November 16, 2007.

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Friday, January 11, 2008

Researchers make breakthrough in silicon nanowires that convert waste heat into electricity

Energy now lost as heat during the production of electricity could be harnessed through the use of silicon nanowires synthesized via a technique developed by researchers with the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) at Berkeley. The far-ranging potential applications of this technology include (bio)hydrogen fuel cell-powered cars, personal power-jackets that could use heat from the human body to recharge electronic devices and highly efficient, decentralised and miniaturised bioenergy power systems.

The thermoelectric nanowires are especially relevant to bioenergy in that biomass is the only common form of renewable energy that is used as a carbonaceous feedstock in thermal power systems (contrary to wind, hydropower and photovoltaics, which don't generate heat). Converting biomass into electricity while using the large amount of heat released in a useful way, is one of the most cost-effective and energy efficient ways to use the resource - much more so than using it for liquid biofuels. But cogeneration (combined heat and power) and district heating systems are relatively costly or require extensive infrastructures. The new nanowires would allow a new form of efficient waste-heat recovery and could miniaturize decentralised bioenergy systems, making them particularly suitable for the developing world.

As in fossil fuel based thermal power plants, biomass plants are currently only about 30–40 per cent efficient and lose more heat to the environment than is converted into electricity. Capturing this low-grade waste heat directly as electricity could make such power systems far more efficient and make a huge difference in the fight against climate change.

Berkeley researchers Arun Majumdar and Peidong Yang describe their findings in the January 10, 2008 edition of the journal Nature, entitled "Enhanced Thermoelectric Performance of Rough Silicon Nanowires". Majumdar, who was recently appointed director of Berkeley Lab's Environmental Energy Technologies Division (EETD) and is a member of the Materials Sciences Division, is an expert on energy conversion and nanoscale science and engineering. Yang is a leading nanoscience authority with Berkeley Lab's Materials Sciences Division and with the UC Berkeley Chemistry Department.
We’ve shown that it’s possible to achieve a large enhancement of thermoelectric energy efficiency at room temperature in rough silicon nanowires that have been processed by wafer-scale electrochemical synthesis. - Peidong Yang, principal investigator
The study describes a unique "electroless etching" method by which arrays of silicon nanowires are synthesized in an aqueous solution on the surfaces of wafers that can measure dozens of square inches in area. The technique involves the galvanic displacement of silicon through the reduction of silver ions on a wafer’s surface. Unlike other synthesis techniques, which yield smooth-surfaced nanowires, this electroless etching method produces arrays of vertically aligned silicon nanowires that feature exceptionally rough surfaces. The roughness is believed to be critical to the surprisingly high thermoelectric efficiency of the silicon nanowires.

The rough surfaces are definitely playing a role in reducing the thermal conductivity of the silicon nanowires by a hundredfold, but at this time the researchers don't fully understand the physics, said Majumdar. They cannot say exactly why it works, but they definitely the technique's results.

Nearly all of the world’s electrical power, approximately 10 trillion Watts, is generated by heat engines powered by either fossil fuels, nuclear energy or biomass: giant gas or steam-powered turbines that convert heat to mechanical energy, which is then converted to electricity. Much of this heat, however, is not converted but is instead released into the environment - approximately 15 trillion Watts. If even a small fraction of this lost heat could be converted to electricity, its impact on the energy situation would be enormous.
Thermoelectric materials, which have the ability to convert heat into electricity, potentially could be used to capture much of the low-grade waste heat now being lost and convert it into electricity. This would result in massive savings on fuel and carbon dioxide emissions. The same devices can also be used as refrigerators and air conditioners, and because these devices can be miniaturized, it could make heating and cooling much more localized and efficient. - Arun Majumdar, principal investigator
However the on-going challenge for scientists and engineers has been to make thermoelectric materials that are efficient enough to be practical. The goal is a value of 1.0 or more for a performance measurement called the “thermoelectric figure of merit” or ZT, which combines the electric and thermal conductivities of a material with its capacity to generate electricity from heat. Because these parameters are generally interdependent, attaining this goal has proven extremely difficult:
:: :: :: :: :: :: :: :: :: :: ::

In recent years, ZT values of one or more have been achieved in thin films and nanostructures made from the semiconductor bismuth telluride and its alloys, but such materials are expensive, difficult to work with, and do not lend themselves to large-scale energy conversions.
Bulk silicon is a poor thermoelectric material at room temperature, but by substantially reducing the thermal conductivity of our silicon nanowires without significantly reducing electrical conductivity, we have obtained ZT values of 0.60 at room temperatures in wires that were approximately 50 nanometers in diameter. By reducing the diameter of the wires in combination with optimized doping and roughness control, we should be able to obtain ZT values of 1.0 or higher at room temperature. - Peidong Yang, principal investigator
The ability to dip a wafer into solution and grow on its surface a forest of vertically aligned nanowires that are consistent in size opens the door to the creation of thermoelectric modules which could be used in a wide variety of situations. For example, such modules could convert the heat from automotive exhaust into supplemental power for a Freedom CAR-type vehicle, or provide the electricity a conventional vehicle needs to run its radio, air conditioner, power windows, etc. You can siphon electrical power from just about any situation in which heat is being given off, heat that is currently being wasted, Majumdar said. For example, if it is cold outside and you are wearing a jacket made of material embedded with thermoelectric modules, you could recharge mobile electronic devices off the heat of your body. In fact, thermoelectric generators have already been used to convert body heat to power wrist watches.

When scaled up, thermoelectric modules could eventually be used in co-generating power with gas or steam turbines fueled by nuclear or carbonaceous feedstocks, including biomass.

The Berkeley Lab researchers will be studying the physics behind this phenomenon to better understand and possibly manipulate it for even further improvements. They will also concentrate on the design and fabrication of thermoelectric modules based on silicon nanowire arrays. Berkeley Lab’s Technology Transfer Department is now seeking industrial partners to further develop and commercialize this technology.

This research was funded by the U.S. Department of Energy's Office of Basic Energy Science, through the Division of Materials Sciences and Engineering.


Figure 1
(click to enlarge): Rough silicon nanowires synthesized by Berkeley Lab researchers demonstrated high performance thermoelectric properties even at room temperature when connected between two suspended heating pads. In this illustration, one pad serves as the heat source (pink), the other as the sensor.

Figure 2 (click to enlarge): (a) is a cross-sectional scanning electron microscope image of an array of rough silicon nanowires with an inset showing a typical wafer chip of these wires. Figure (b) is a transmission electron microscope image of a segment of one of these wires in which the surface roughness can be clearly seen. The inset shows that the wire is single crystalline all along its length.

References:
Allon I. Hochbaum, Renkun Chen, Raul Diaz Delgado, Wenjie Liang, Erik C. Garnett, Mark Najarian, Arun Majumdar and Peidong Yang1, "Enhanced thermoelectric performance of rough silicon nanowires", Nature 451, 163-167 (10 January 2008) | doi:10.1038/nature06381

Lawrence Berkeley National Laboratory: Feeling the Heat: Berkeley Researchers Make Thermoelectric Breakthrough in Silicon Nanowires - January 9, 2008.

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