Biofuels - July 26
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Green Energy, Part 2: Ethanol and Biodiesel
Andrew K. Burger, www.TechNewsWorld.com
Each biofuel, be it ethanol, biodiesel or vegetable oil, has its particular advantages and disadvantages, as well as proponents and detractors. However, ethanol and biodiesel may not be the best choice in terms of potential purposes, energy efficiency and environmental effects, according to a number of research studies.
...Although it seems that the pendulum has definitively shifted in the direction of building a diversified renewable energy infrastructure, the extent to which the U.S. does so, and which energy sources will be made use of, remains unclear. Three decades after the first OPEC oil crisis, our economic and material well-being, as well as our international diplomatic and military policies, are still inextricably bound to the production and consumption of petroleum and other fossil fuels. What transpires will have a profound impact on our environment, economy, national security.
(20 July 2006)
More realistic than the usual article about biofuels. -BA
Redesigning Life to Make Ethanol
Jamie Shreeve, Technology Review (MIT)
Genetically engineered organisms can more efficiently produce ethanol from cheap and abundant sources of biomass, such as agricultural waste. It could make ethanol cost competitive.
...Converting cellulose to ethanol involves two fundamental steps: breaking the long chains of cellulose molecules into glucose and other sugars, and fermenting those sugars into ethanol. In nature, these processes are performed by different organisms: fungi and bacteria that use enzymes (cellulases) to "free" the sugar in cellulose, and other microbes, primarily yeasts, that ferment sugars into alcohol.
In 2004, Iogen, a Canadian biotechnology company based in Ottawa, began selling modest amounts of cellulosic ethanol, made using common wheat straw as feedstock and a tropical fungus genetically enhanced to hyperproduce its cellulose-digesting enzymes. But Iogen estimates that its first full-scale commercial plant, for which it hopes to break ground in 2007, will cost $300 million -- five times the cost of a conventional corn-fed ethanol facility of similar size.
The more one can fiddle with the ethanol-producing microbes to reduce the number of steps in the conversion process, the lower costs will be, and the sooner cellulosic ethanol will become commercially competitive. In conventional production, for instance, ethanol has to be continually removed from fermentation reactors, because the yeasts cannot tolerate too much of it. MIT's Greg Stephanopoulos, a professor of chemical engineering, has developed a yeast that can tolerate 50 percent more ethanol. But, he says, such genetic engineering involves more than just splicing in a gene or two. "The question isn't whether we can make an organism that makes ethanol," says Stephanopoulos. "It's how we can engineer a whole network of reactions to convert different sugars into ethanol at high yields and productivities. Ethanol tolerance is a property of the system, not a single gene. If we want to increase the overall yield, we have to manipulate many genes at the same time."
The ideal organism would do it all -- break down cellulose like a bacterium, ferment sugar like a yeast, tolerate high concentrations of ethanol, and devote most of its metabolic resources to producing just ethanol.
...In the short term, some advances in biology and engineering are needed before fuels made from biomass will be practical and competitive with fossil fuels. But in the longer term, says Venter, "we're limited mostly by our imagination, not by the limits of biology."
(21 July 2006)
Most promises that we can exceed the limits of biology end in disaster. -BA
Biofuel demand creates chain reaction
Food companies such as Unilever, Nestle and Cadbury could face higher commodity costs over the long term as rising demand for biofuels pushes up prices for raw materials such as wheat, corn and sugar, according to a report by Goldman Sachs.
The development of bio-fuels - fuels produced from renewable organic sources such as corn and sugar crops - is starting to accelerate more rapidly as governments seek alternatives to more expensive oil-based energy sources.
Demand for biofuels is pushing up crop prices, making it more expensive for food companies to source the raw materials used in their products.
(25 July 2006)
Ethanol's rise prompts worries of a corn crunch
Mark Clayton, Christian Science Monitor
Some see a competition between food and fuel as corn growers begin to provide a significant energy source.
Iowa's corn fields may seem like endless green oceans, but if dozens of new corn-to-ethanol biorefineries now in development are all built, they could swallow most of the state's corn crop.
Amid America's rush to replace gasoline with homegrown alternatives like corn-based ethanol, some researchers worry that the results may benefit motorists at the expense of higher food costs and fewer US crop exports. It also raises ethical and environmental questions about the best uses of crop land.
Fresh signs of ethanol's new economic impact are expected soon. After languishing for years, corn prices are projected to rise about 25 percent from around $2.00 a bushel currently to $2.45 a bushel this next crop year, reports the US Department of Agriculture (USDA). But as ethanol demand for corn kicks in, prices could go much higher in the future depending on gasoline prices. Meat and grocery prices could eventually rise as well, some analysts say.
"Ethanol has had huge impact on corn markets," says Jason Hill, a University of Minnesota researcher and coauthor of a study on ethanol's environmental impact published in the proceedings of the National Academy of Science last month. "Competition between food and fuel is growing, along with the environmental consequences as more ethanol facilities are built," the study says.
(25 July 2006)
Agency Seeks to Develop Military Aviation Biofuel
Blackanthem Military News
The Defense Advanced Research Projects Agency is soliciting energy alternatives and fuel efficiency efforts in a bid to reduce the military's reliance on traditional fuel for aircraft.
The Defense Advanced Research Projects Agency (DARPA) has released a solicitation calling for the exploration of energy alternatives and fuel efficiency efforts in a bid to reduce the military's reliance on traditional fuel for aircraft.
DARPA is looking for processes that will efficiently produce alternative non-petroleum based military jet fuel from agriculture or aquaculture crops.
Current commercial processes do not produce alternative fuels that meet the higher energy density and wide operating temperature range necessary for military aviation uses.
The program is currently outlined in a recently issued broad agency announcement and is known as The BioFuels program.
The goal of the BioFuels program is to develop an affordable alternative production process that will achieve a 60 percent or greater conversion efficiency, by energy content, of crop oil to military aviation fuel (JP-8) and elucidate a path to 90 percent conversions.
(24 July 2006)
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