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News and Trends
http://www.ias.ac.in/currsci/aug102008/321.pdf A paper by Ajay C. Deore and T. Sudhakar Johnson reports an occurrence of vivipary in Jatropha curcas, a popular biofuel crop in developing countries. Jatropha seeds are usually processed for oil extraction and the oil is reacted with an alcohol (methanol or alcohol) for biodiesel production. Vivipary is a condition where “the embryo (the young plant within the seed) grows first to break the seed coat, then out of the fruit wall while still attached to the parent plant (precocious germination). This is not a desirable condition in commercial Jatropha plantations when seeds are harvested. Vivipary is apparently a rare occurrence in Jatropha; to the knowledge of the authors, there has been no report of vivipary in Jatropha. The authors presume that a combination of “intrinsic and extrinsic factors” such as physiology, soil condition, temperature and dry spell followed by high humidity induced by heavy rainfall may be involved. The occurrence of vivipary in Jatropha, aside from being an interesting area of research, may have implications on commercial seed harvesting. The authors mention that “a commercial planter needs to take the precocious germination of J. curcas seeds into consideration, particularly in high humid regions while harvesting fruits. The physiologically matured yellow fruits should be "harvested without much delay”. The report appears in the August 10 issue of the journal, Current Science. Related information on vivipary: http://mangrove.nus.edu.sg/guidebooks/text/1044.htm
http://www.biofuelreview.com/content/view/1705/1/ A recent study by Accenture (a global management consulting, technology services and outsourcing company) says that “the creation of a global biofuels industry will be much more difficult to achieve than originally thought”. The study entitled, “Biofuels' time of transition: Achieving high performance in a world of increasing fuel diversity", predicts that biofuels will eventually account for 10% to 15% of the future global energy mix, but getting there will be difficult, “reflecting the challenges involved in creating full-scale markets in biofuels feedstock, production, transport and distribution”. The study identifies challenges in three key areas that need to be addressed: (1) environment: the ‘food vs. fuel debate” will slow demand, and the challenge is for governments to address sustainability issues, (2) distribution: tough decisions will have to be made regarding “storing, blending and accommodating different grades of biofuels”, (3) infrastructure investment: the challenge is to justify the massive up-front infrastructure investment to support large scale biofuel operations/trading, “when the ultimate returns and size of the market are uncertain”. Among the findings of the study are: (1) second generation biofuels (i.e. cellulose ethanol) will be used in tandem with first generation biofuels (i.e. corn or cane ethanol) for a number of years, (2) “the fragmented "patchwork" of local-market regulations across the world is helping to drive a shift away from a global and super-efficient petroleum market, to a fuels market with fragmented pools of supply and demand and varying mixes of fuels”..
http://www.biodieselmagazine.com/article.jsp?article_id=2719 A 13-week vehicle-study was made by a renewable fuel retailer (Propel, Inc.) for a baking company (The Essential Baking Company), to assess the effect of fuel replacement from mineral (petro-) diesel to B99 (99% biodiesel blend) on its fleet of delivery vehicles. The results of the study (done in the United States) showed that biodiesel in its almost pure form (i.e., 99% blend) performed equally (if not, better) than regular petrodiesel. During the testing period, the test vehicles (of different models, route types, and mileage driven) traveled about 37,000 miles on 2,500 gallons of B99 biodiesel. The vehicles ran more smoothly, without any mechanical issues. There were also no cold weather problems encountered. Some drivers reported that their vehicles ran more quietly on the B99 blend compared to regular petrodiesel. Using an “integrated carbon emission reduction tracking platform” which automatically tracks gallons and calculates the fleet’s reduction in carbon dioxide (and other pollutant) emissions, the 13-week study showed that B99-powered vehicles had: (1) a reduction in carbon dioxide emissions by 43,000 pounds, (2) a displacement of 1,553 gallons of petroleum oil, (3) a 78% reduction in particulate matter emissions, (4) a 60% to 80% reduction in air toxins emissions, and (5) a 100% reduction in the emissions of sulfur compounds.. Energy Crops and Feedstocks for Biofuels Production
http://www.purdue.edu/UNS/x/2008b/080827CarpitaBioenergy.html Scientists from Purdue University (United States) are studying “genes involved in plant cell wall generation and learning their function”, with the objective of using the results to develop the next generation biofuel feedstocks. The so-called, “third generation biofuel feedstocks” can be described as ‘designer bioenergy crops” whose characteristics have been modified to suit a particular processing requirement (for example, bioenergy crops with low lignin content for cellulose ethanol production). The scientists, Nick Carpita and Maureen McCann, "will study genes involved in the formation of cell walls in the group of plants known as grasses, which includes corn”, with the aim of developing improved crops that can be processed into biofuels. According to Biological Science Associate Professor McCann, "Maize has the same genes arranged in the same order and on the same chromosomes as the other grasses. We'll switch genes on and off as we identify them to see what they do. Once we know the genes and their functions, then we can assess which ones might make good targets for modification for enhanced biomass and sugars for processing into biofuel.”. Biofuels Processing
http://www.umass.edu/newsoffice/newsreleases/articles/76713.php A scientific team from the University of Massachusetts Amherst (United States) has received a research grant to study the use of microwave technology for faster and less costly production of biodiesel. The research grant amounting to about 280,000 Euros, will be for the project on “Microwave Enhanced Catalytic Production of Biofuels”. The present methods for biodiesel production involve high inputs of thermal energy to drive the necessary reactions. Conventional heating methods in biodiesel production utilize either electrical or chemical energy. Associated costs for these types of heating are high, hence the need to explore cheaper methods of heat generation. In microwave heating, electromagnetic waves are passed through the material, and cause the molecules to oscillate. The molecular oscillations generate heat which starts within material and then spreads over the entire volume at about the same rate. Microwave heating has been shown to have some advantages over conventional heating because it decreases the energy requirements for a number of reactions in the biodiesel production process. It also decreases the reaction time. The team will couple microwave technology with the use of a solid catalyst which is said to save about "50% of the current costs”. Related information on microwave heating: http://www.ecw.org/prod/433-1mh.pdf
http://www.pnas.org/content/early/2008/09/06/0801266105.abstract The production of cellulose ethanol from plant biomass usually goes through a series of steps involving (1) enzymatic breakdown of the complex cellulose/hemicellulose molecules of the plant biomass into their component sugars and (2) fermentation of the liberated sugars to ethanol (usually by yeasts). Although cellulose ethanol production has higher net energy yield and has a better carbon balance (compared to corn ethanol), its production cost is still high. Cellulose ethanol takes a longer time to produce compared to corn ethanol. The enzymes for cellulose/hemicellulose breakdown are still expensive. Furthermore, much of the non-glucose sugars in the fermentation broth (such as xylose from the breakdown of hemicelluloses) cannot be utilized by yeasts into ethanol. (Yeasts can only utilize the glucose in the broth to ethanol). Some of these hurdles are a step closer to being overcome, when scientists from Dartmouth College and Mascoma Corporation (United States) developed a metabolically engineered bacterium which can utilize the non-glucose sugars (xylose) in the fermentation broth into ethanol, at record breaking product yields and with little by-product formation at thermophilic (45 oC to 80 oC) temperatures. The metabolism of the bacterium, Thermoanaerobacterium saccharolyticum, was modified so that it can co-utilize glucose and xylose (and other sugars like mannose and arabinose) into ethanol at high product yield and with little by-products. The maximum ethanol titer produced by one strain was 37 g/liter, “the highest reported thus far for a thermophilic anaerobe”. Yeasts can reach only to as high as 10 to 12 g/L of ethanol. The research findings are reported in a recent issue of the Proceedings of the National Academy of Sciences (PNAS) (URL above). Related information on thermophilic microorganisms and hemicelluloses: http://en.wikipedia.org/wiki/Thermophilic_bacteria Biofuels Policy and Economics
http://www.biofuelreview.com/content/view/1704/ The New Zealand Parliament recently passed a Biofuels Bill which is seen to “stimulate the market for alternative transport fuels” in the country. Under the legislation, oil companies are bound by a “biofuel sales obligation” which requires them to have 0.5% of their sales to be from biofuel sales. The obligation will increase in 0.5% increments up to 2.5% by 2012. “Sustainability principles” are embedded in the legislation which will ensure that the biofuels sold under the obligation will (1) emit less greenhouse gases “over their life cycles” relative to fossil fuels, (2) does not have negative impacts on food production, and (3) does not adversely affect indigenous biodiversity and lands with “high conservation value”. The legislation also allows an increasing proportion of locally produced biofuels to come from by-product sources (such as those from the dairy or beef industry), as well as from sustainable sources (i.e., fast growing trees and grasses grown on marginal land, and algae from cultivated sewage ponds).. |
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