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An Ethanol and/or Solar
and/or Wind Anything Into Ethanol Forget about corn-future biofuels will be made of wood chips and trash. by Robb Mandelbaum published online October 3, 2008 http://discovermagazine.com/2008/oct/03-anything-into-ethanol - - - Excerpts: Biofuels could be a crucial weapon against both rising temperatures and dwindling global oil sup- plies. They are made from organic material such as plants, so they essentially recycle existing car- bon in the atmosphere instead of releasing new carbon from the depths of the earth; they are also, in principle, endlessly renewable. But the best-known biofuel, ethanol, is looking decidedly unpromising right now. Today most ethanol in the United States is made from corn, using an energy-intensive process that may not actually save a lot of fossil fuel, and in any case America cannot produce enough ethanol from corn to really matter. Scientists have long tried to devise an efficient way to make ethanol from a wider range of raw materials, especially waste products rather than food. The U.S. government has calculated that the country could generate 1.4 billion tons of biomass a year. This could make 100 billion gallons of fuel or more, enough to meet much of America's demand for motor gasoline. One approach to tapping into all that biomass focuses on cellulose, the material that gives plant cells their strong walls. The cellulose is converted into sugar and then from sugar into ethanol. But despite decades of research, the technology is still far from commercially viable. Now several companies, including Coskata and Range Fuels, say they have cracked the problem. They are pursuing a different strategy, one that turns any carbon-rich matter into a gas, which is then converted to liquid fuel. This approach can use any organic material, so the potential sources for this fuel are virtually unlimited. Soon, the companies claim, they will be able to refine vast quantities of non- corn ethanol. ... Click here to see the rest of DISCOVERmagazine.com's special energy coverage. http://discovermagazine.com/2008/oct/24-the-future-of-energy - - - end excerpts - - - - - - Powering the Planet With Sun-Harnessing Balloons One innovator says the greatest threat to a clean- energy world is kids with BB guns. by Fred Hapgood published online September 19, 2008 http://tinyurl.com/sunharnessingballoons - - - Excerpts: ... A few years back, a group of West Coast engineers were puzzling over a practical way to tackle the problem, looking for a hydrocarbon-free, clean, and renewable energy system that required no major technical breakthroughs and could be put to work in the next few years. The result: the start-up Cool Earth Solar ... and its new-think technology, an inexpensive plastic- film balloon a bit over eight feet tall. Millions of these balloons could hover low over the landscape, each concentrating sunlight onto a photovoltaic cell inside, and pumping out elec- tricity more cheaply than power from fossil fuels, the company says. ... Why is solar power a better energy source than wind, geothermal, biofuels, and nuclear? Don't we need them all? Solar seems to have the best economics. It cer- tainly has all the energy we need and will need for a long time. What are the potential problems with solar bal- loons? It would be nice to put this out in the field and have it last 30 years. But the thin film won't last that long, so we intend to replace it every couple of years. On a 1-kilowatt concentrator, that's a couple dollars' worth of plastic, so it's not some- thing that hurts us. ... By this time next year, we hope to start building a series of standardized plants, each consisting of thousands of balloons and about 10 to 30 million watts in size. [A 30-million-watt plant would have about 30,000 balloons.] The goal would be selling electricity directly to utility companies. A few years from now, we would like to be adding hundreds of megawatts of capacity every year. - - - end excerpts - - - - - - High-Flying Windmills Blow Away Their Ground-Based Cousins Next-generation turbines may catch all the energy we need, thousands of feet up. by Fred Hapgood published online September 24, 2008 http://tinyurl.com/highflyingwindmills - - - Excerpts: Wind power has long been touted as a major energy resource, but for decades no one knew how much energy it could actually yield. Then three years ago Stanford University atmos- pheric scientists ... did a detailed calculation based on known patterns of air motion. Using a conservative approach, they counted only the energy that could be generated from winds blow- ing over land at an altitude of 80 meters, the approximate height of a typical modern wind turbine. Under perfect conditions, the total would be 72 trillion watts. It is a handsome quantity. In 2007 the entire elec- trical generating capacity of the United States was just a bit more than 1 trillion watts. But Archer realized that this number barely hints at the potential. Wind speed rises with altitude, and available power rises at the cube of wind speed. This means that 72 trillion watts is a low- ball estimate. A few miles up, a turbine blade could generate up to 250 times the energy of the same blade near the ground. The prospect, Archer says, "is just super-incredibly exciting." One scheme for harvesting that breezy bounty comes from Bryan Roberts, an engineering professor at the University of Technology in Sydney, Australia, and Sky WindPower, the San Diego-based company developing his work. The team is designing kites with rotors that fly helicopter-style to altitudes of a mile or more, where the winds are strongest. Upon arrival, the rotors switch to generating mode, sending current down their tethers, which might be many miles long. ... - - - end excerpts - - - - - - Can Engineers Achieve the Holy Grail of Energy: Infinite and Clean? All they need to do is tame 200-million- degree plasma-without using too much energy. by Charles Seife published online October 6, 2008 http://tinyurl.com/fusion-holygrailofenergy - - - Excerpts: For more than half a century, engineers have been trying to build a miniature sun in a bottle: a fusion reactor. Now an international team is embarking on the most intense effort ever to make it happen. If the group succeeds, we could soon generate nearly boundless power from an isotope of hydrogen that is plentiful in our oceans. That's a big if, though. ... Researchers from Europe, Japan, the United States, China, India, South Korea, and Russia are working to break the power barrier by building the best plasma container ever devised, known as the Inter- national Thermonuclear Experimental Reactor, or ITER. After more than two decades of planning, the $15 billion project is finally getting under way in southern France. ITER will house a doughnut-shaped magnetic vessel, called a tokamak, with a diameter of 17 meters [56 feet]. It will be surrounded by superconducting nio- bium coils that create magnetic fields 100,000 times as powerful as Earth's. These fields will do double duty: They will heat a cloud of hydrogen to the sear- ing temperature required for fusion while forcing the resulting plasma to sit in a ring-shaped cloud away from the tokamak's walls. The goal of fusion physicists is to use the heat from a fusing plasma to keep the reaction going indefinitely, without the need to pump in external energy. ITER will not quite get to that point, but with luck, when the reactor is turned on in 2018, it will be able to hold a burning plasma for five minutes or more, allowing it to release 10 times as much energy as is put in. That would make ITER the first fusion reactor to produce a net surplus of energy. Scientists can then begin working out how to harvest fusion energy for practical use. ... - - - end excerpts - - -
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