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NREL: Learning - Biofuels Basics - 0 views

  • Unlike other renewable energy sources, biomass can be converted directly into liquid fuels, called "biofuels," to help meet transportation fuel needs
  • Today, ethanol is made from starches and sugars, but NREL scientists are developing technology to allow it to be made from cellulose and hemicellulose,
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HowStuffWorks "How Fuel Cells Work" - 1 views

  • The fuel cell will compete with many other energy­ conversion devices, including the gas turbine in your city's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.
  • Sir William Grove invented the first fuel cell in 1839. Grove knew that water could be split into hydrogen and oxygen by sending an electric current through it (a process called electrolysis). He hypothesized that by reversing the procedure you could produce electricity and water. He created a primitive fuel cell and called it a gas voltaic battery. After experimenting with his new invention, Grove proved his hypothesis. Fifty years later, scientists Ludwig Mond and Charles Langer coined the term fuel cell while attempting to build a practical model to produce electricity.
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    " Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently."
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A Basic Overview of Fuel Cell Technology - 0 views

  • they generate electricity with very little pollution—much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
  • Scientists and inventors have designed many different types and sizes of fuel cells in the search for greater efficiency, and the technical details of each kind vary
  • in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now “ionized,” and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
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  • But in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now �ionized,� and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
  • Every fuel cell also has an electrolyte, which carries electrically charged particles from one electrode to the other, and a catalyst, which speeds the reactions at the electrodes. Hydrogen is the basic fuel, but fuel cells also require oxygen. One great appeal of fuel cells is that they generate electricity with very little pollution–much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
  • A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes.
  • fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode.
  • One detail of terminology:
  • Oxygen enters the fuel cell at the cathode and, in some cell types (like the one illustrated above), it there combines with electrons returning from the electrical circuit and hydrogen ions that have traveled through the electrolyte from the anode. In other cell types the oxygen picks up electrons and then travels through the electrolyte to the anode, where it combines with hydrogen ions. The electrolyte plays a key role. It must permit only the appropriate ions to pass between the anode and cathode. If free electrons or other substances could travel through the electrolyte, they would disrupt the chemical reaction. Whether they combine at anode or cathode, together hydrogen and oxygen form water, which drains from the cell. As long as a fuel cell is supplied with hydrogen and oxygen, it will generate electricity. Even better, since fuel cells create electricity chemically, rather than by combustion, they are not subject to the thermodynamic laws that limit a conventional power plant (see "Carnot Limit" in the glossary). Therefore, fuel cells are more efficient in extracting energy from a fuel. Waste heat from some cells can also be harnessed, boosting system efficiency still further
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    "A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes."
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    "A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode."
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How Solar Energy Works | Union of Concerned Scientists - 0 views

  • By the time it reaches Earth's surface, the energy in sunlight has fallen to about 1,000 watts per square meter at noon on a cloudless day. Averaged over the entire surface of the planet, 24 hours per day for a year, each square meter collects the approximate energy equivalent of almost a barrel of oil each year, or 4.2 kilowatt-hours of energy every day. Deserts, with very dry air and little cloud cover, receive the most sun—more than six kilowatt-hours per day per square meter. Northern climates, such as Boston, get closer to 3.6 kilowatt-hours. Sunlight varies by season as well, with some areas receiving very little sunshine in the winter. Seattle in December, for example, gets only about 0.7 kilowatt-hours per day. It should also be noted that these figures represent the maximum available solar energy that can be captured and used, but solar collectors capture only a portion of this, depending on their efficiency. For example, a one square meter solar electric panel with an efficiency of 15 percent would produce about one kilowatt-hour of electricity per day in Arizona.
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Fuel cell - Wikipedia, the free encyclopedia - 0 views

  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied.
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  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent
  • There are many types of fuel cells, but they all consist of an anode (negative side), a cathode (positive side) and an electrolyte that allows charges to move between the two sides of the fuel cell.
  • The principle of the fuel cell was discovered by German scientist Christian Friedrich Schönbein in 1838
  • Stationary fuel cells are used for commercial, industrial and residential primary and backup power generation. Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, communications centers, rural locations including research stations, and in certain military applications. A fuel cell system running on hydrogen can be compact and lightweight, and have no major moving parts. Because fuel cells have no moving parts and do not involve combustion, in ideal conditions they can achieve up to 99.9999% reliability.[49] This equates to less than one minute of downtime in a six-year period.
  • Although there are currently no Fuel cell vehicles available for commercial sale, over 20 FCEVs prototypes and demonstration cars have been released since 2009. Demonstration models include the Honda FCX Clarity, Toyota FCHV-adv, and Mercedes-Benz F-Cell.[64] As of June 2011 demonstration FCEVs had driven more than 4,800,000 km (3,000,000 mi), with more than 27,000 refuelings.[65]
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used.
  • The fuel cell he made used similar materials to today's phosphoric-acid fuel cell.
  • In 2003, U.S. President George W. Bush proposed the Hydrogen Fuel Initiative (HFI). This aimed at further developing hydrogen fuel cells and infrastructure technologies with the goal of producing commercial fuel cell vehicles. By 2008, the U.S. had contributed 1 billion dollars to this project
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    "A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied."
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    Explains what a fuel cell is.
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    "Individual fuel cells produce relatively small electrical potentials, about 0.7 volts, so cells are "stacked", or placed in series, to increase the voltage and meet an application's requirements.[2] In addition to electricity, fuel cells produce water, heat and, depending on the fuel source, very small amounts of nitrogen dioxide and other emissions. The energy efficiency of a fuel cell is generally between 40-60%, or up to 85% efficient if waste heat is captured for use."
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    "A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used."
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Biofuel crops may worsen global warming: study - CTV News - 0 views

  • "Our study found that any biofuel that causes clearing of natural ecosystems will increase global warming," Joe Fargione, a scientist for The Nature Conservancy, told CTV.ca.
  • He said converting natural areas into croplands results in tons of carbon being emitted into the atmosphere -- a carbon 'debt' that outweighs any benefits.
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Cheap fuel cells real soon? - Democratic Underground - 0 views

  • Scientists have come up with a more efficient way to split ocean water and turn it into sustainable, clean hydrogen fuel. They created a flexible plastic film that acts as the catalyst to begin splitting ocean water, without requiring the high energy input that current methods need.
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Fuel cell - Simple English Wikipedia, the free encyclopedia - 0 views

  • t has to be produced first, and if this is done by burning fossil fuels, it does not help against climate change. But, the hydrogen fuel cell will help against climate change in future, because scientists are trying to find new ways to make hydrogen without using fossil fuels.
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BBC News - UK tidal power has huge potential, say scientists - 0 views

  • Despite high costs, experts say tidal power is more reliable than wind.
  • The UK is underestimating the amount of electricity that could be generated from tidal sources, new research says.
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    Despite high costs, experts say tidal power is more reliable than wind.
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Wind Turbines - Kinetic wind energy generator technology - 0 views

  • Though our scientists may claim that they are inventing something new by using wind as a source of generating energy, the truth is that wind is being used for centuries for this purpose. An example of this is an article published in 1838, which clearly shows that even in those times, wind was considered an important source of energy. Here are a few quotes that were recorded in the past, which prove that wind was always important in generating energy
  • Renewable energy production and demand growth is gaining momentum in many ways across the world. There is a booming demand of wind power today and all wind energy equipment manufacturers are gearing up to meet the demand and take advantage of it. Wind power capacity growth will be reaching 447GW in the next five years and by year 2014 end, Asia will lead the world in installed wind capacity.
  • Yes, the day is not far off when reaching for sky is the new motto for generating cost-effective renewable energy. Initially it was considered to be technically non-viable to tap high-altitude winds. But today, technically-advanced materials and innovative computer know-how are giving new life to this scheme with innovative autonomous aerial structures using wind energy to generate power
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  • It's an expert estimation that the total energy stored in wind is 100 times higher than actually needed by humans on this earth. The catch is that we have to learn and devise ways to trap this wind power blowing across the planet earth. Experts tell us one more thing that most of the wind energy is available at high altitude and we can’t manufacture turbines of that height. So we have to think of new ways to trap that wind power blowing at a significant height. Some experts estimate that the total energy contained in wind is 100 times the amount needed by everyone on the planet. However, most of this energy is at high altitudes, far beyond the reach of any wind turbine.
  • A research company in New Hampshire recently patented its bladeless wind turbine, which is based on a patent issued to Nikola Tesla in 1913. This wind turbine is christened as the Fuller Wind Turbine. This turbine is developed by Solar Aero. The specialty of Fuller Wind Turbine is it has only one rotating part, known as the turbine-driveshaft. The entire machinery is assembled inside a housing. Wind turbines are often disliked by environmentalists because they kill birds and bats and often generate noise for the residents living nearby
  • Presently Fluid Dynamics Expert, John Dabiri, is very much on the quest of improving designs of wind turbines. Spotting behaviours that may throw light on energy-related practices in biological system and trying to implement that in real-life situations is part of that quest and Mr.Dabiri is jubilant that he is learning lessons from a school of fish! Water-energy, and wind energy are both studied.
  • GE, the US industrial group, is promoting and showing confidence in offshore wind technology by buying ScanWind, which makes direct-drive turbine components. This move will help in generating thousands of new jobs in the field of designing and manufacturing turbines. This move will affirm the confidence of investors in the fledgling offshore wind industry, which has been weighed down by concerns about costs and reliability. GE is moving ahead with establishing turbine manufacturing facilities to serve the European markets at first. They have to make up their mind about the size of the investment and location
  • The Metropolis Magazine has been holding Next Generation Design Competition since 2003. They want to provide a platform for young designers to promote the spirit of activism, social involvement, and entrepreneurship. They offer prize money of $ 10,000. But the real attraction is the publicity given to the projects of winners and runners-up. This recognition helps abstract ideas take concrete forms. For 2009, the theme for the Next Generation Design Competition was: How do we fix our energy addiction? They offered some guidelines, "Think about how we live and work, what we use, how we get where we need to go, hidden costs to our pocket books and the environment, across the whole design spectrum. Focus on one area that needs fixing—products, interiors, buildings and landscape, communication systems, or anything else you can imagine—and develop your idea fully. And above all, think of our energy addiction as a design problem at all scales."
  • sector. Wind turbines generate clean and green power for us but they have certain precondition. One of it is the power unit has to be set up in strong wind area. But Green Energy Technologies has developed a brand new wind power generator known as the WindCube. It is smaller compared to the normal wind generator. WindCube is specially designed to set up on the roof of a building in urban and rural areas. WindCube carries a 22 x 22 x 12 feet framework and its single unit can produce a maximum of 60kW of power
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How Biomass Energy Works | Union of Concerned Scientists - 0 views

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    In the United States, we already get over 50 billion kilowatt-hours of electricity from biomass, providing nearly 1.5 percent of our nation's total electric sales.
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