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jack wells

Wind Program: Frequently Asked Questions about Wind Energy - 2 views

  • What is wind energy? Wind energy (or wind power) refers to the process by which wind turbines convert the movement of wind into electricity. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Humans use this wind flow for many purposes: sailing boats, pumping water, and also generating electricity. Wind turbines convert the kinetic energy of the moving wind into electricity.
  • Birds and bats are occasionally killed in collisions with wind turbines. Like any form of development, wind projects can also negatively impact wildlife by altering habitat. Over the past two decades, the impact of wind development on birds has been greatly reduced by improvements in turbine design and particularly through improved project and turbine siting.
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    How do wind turbines work? A wind turbine works like a fan, but in reverse: instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the turbine's blades, which spin a shaft connected to a generator to make electricity.
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    wind energy facts.
Connor Wiggins

fuel cell Facts, information, pictures | Encyclopedia.com articles about fuel cell - 0 views

  • Fuel cells convert chemical energy to electrical energy by combining hydrogen from fuel with oxygen from the air. Hydrogen fuel can be supplied in two ways—either directly as pure hydrogen gas or through a "fuel reformer" that converts hydrocarbon fuels such as methanol, natural gas, or gasoline into hydrogen-rich gas. A fuel cell's only emission is water.
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    What fuel cell is and how its made 
conboyeri98

Fuel Cells | Energy Sources | Chevron - 0 views

  • Fuel cells are self-contained power generation devices that are able to produce reliable electricity for residential, commercial, industrial and transportation applications. A fuel cell can convert hydrogen directly into electricity that can be used to power an electric car, for example, or a home.
  • In fuel cells, the use of hydrogen produces fewer greenhouse gases than does burning fossil fuels
  • . Fuel cells convert energy efficiently, which helps conserve energy resources. And a byproduct of this electro-chemical process is pure water—a clear benefit for the environment
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  • However, hydrogen—a tasteless, odorless, colorless gas—is not found freely in nature. It must be extracted from other substances.
tavarreskat99

Tidal Energy | Pros for Wave and Tidal Power - 3 views

  • Tidal energy is one of the oldest forms of energy used by humans. Indeed, tide mills, in use on the Spanish, French and British coasts, date back to 787 A.D.. Tide mills consisted of a storage pond, filled by the incoming (flood) tide through a sluice and emptied during the outgoing (ebb) tide through a water wheel. The tides turned waterwheels, producing mechanical power to mill grain. We even have one remaining in New York- which worked well into the 20th century.
  • Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
  • A tidal range of at least 7 m is required for economical operation and for sufficient head of water for the turbines
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  • Currently, although the technology required to harness tidal energy is well established, tidal power is expensive, and there is only one major tidal generating station in operation. This is a 240 megawatt (1 megawatt = 1 MW = 1 million watts) at the mouth of the La Rance river estuary on the northern coast of France
  • Tidal electricity can be used to displace electricity which would otherwise be generated by fossil fuel (coal, oil, natural gas) fired power plants, thus reducing emissions of greenhouse and acid gasses.
  • There is a high capital cost for a tidal energy project, with possibly a 10-year construction period.
  • Electricity can be generated by water flowing both into and out of a bay. As there are two high and two low tides each day, electrical generation from tidal power plants is characterized by periods of maximum generation every twelve hours, with no electricity generation at the six hour mark in between.
  • Tidal energy is a renewable source of electricity which does not result in the emission of gases responsible for global warming or acid rain associated with fossil fuel generated electricity. Use of tidal energy could also decrease the need for nuclear power, with its associated radiation risks. Changing tidal flows by damming a bay or estuary could, however, result in negative impacts on aquatic and shoreline ecosystems, as well as navigation and recreation.
  • Indeed, tide mills, in use on the Spanish, French and British coasts,
  • date back to 787 A.D..
  • Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
  • idal energy is one of the oldest forms of energy used by humans. Indeed, tide mills, in use on the Spanish, French and British coasts, date back to 787 A.D.. Tide mills consisted of a storage pond, filled by the incoming (flood) tide through a sluice and emptied during the outgoing (ebb) tide through a water wheel. The tides turned waterwheels, producing mechanical power to mill grain. We even have one remaining in New York- which worked well into the 20th century. Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
  • Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
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    "Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable."
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    when it started to be used and who it was used by.
rainwateremi99

The Cost of Biofuels in Guatemala - Photographs - NYTimes.com - 0 views

  • Now that the United States is using 40 percent of its crop to make biofuel, it is not surprising that tortilla prices have doubled in Guatemala, which imports nearly half of its corn. 
jack wells

The Benefits of Wind Power - Green Living Ideas - 0 views

  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.
  • One of the most important is that wind power is the least expensive of all other forms of alternative energy. 
  • Another tremendous benefit of wind power is that it is a sustainable source of energy and a clean source of energy
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  • Wind energy is also a renewable energy, meaning it does not deplete our natural resources like coal or petroleum based products.
  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free.
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    The benefits of wind energy.
lemairenat98

Tidal stream systems - 0 views

shared by lemairenat98 on 12 Mar 13 - No Cached
collignonaut99

Fuel Cell History - Fuel Cell Today - 0 views

  • William Grove, a chemist, physicist and lawyer, is generally credited with inventing the fuel cell in 1839
  • n the late 1950s and early 1960s NASA, in collaboration with industrial partners, began developing fuel cell generators for manned space missions.
    • dpurdy
       
      Great graphic showing history
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    "IntroductionHistoryTechnologiesApplicationsBenefitsFAQGlossaryFurther Reading Home Page About fuel cells History History "
tushabeper99

What are the advantages and disadvantages of solar energy - 0 views

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    "Advantages: Solar power gives you a return on your investment, while paying your utility for electricity gives you 0% return. Solar energy is renewable unlike the conventional resources (coal, oil) which will inevitably run out. Non-polluting, no carbon dioxide like fossil fuels Free except for capital expenses. Longevity - solar panels can last over twenty years Low maintenance - solar panels require very little upkeep Independence - an off-grid system allows you to break free from the electrical grid Environmentally friendly because the conversion of energy doesn't produce any carbon dioxide. It comes from the sun, which, unless you are in The South or North pole, comes out almost everyday Solar power is better for the environment, compared to burning fossil fuels and other electrical power. sun is renewable You get clean energy without harming the environment [in term of carbon emissions] , in certain countries, excessive power generated can be sold back to local electricity provider reduces pollution helps create jobs - shores up economy - to build -> you hire - innovate-maintain - basically economic activities reduced dependence on fossil fuels Once installed, the power is free It is environmentally friendly and no pollution is associated with solar power You can sell your excess power back to the power companies It can be installed anywhere You can use batteries to store power for use at night Energy from the sun is renewable, that is, it keeps on coming It is free It does no damage to the earth or its atmosphere It produces no carbon dioxide It doesn't have to be dug up from the ground like coal, oil, natural gas, or uranium It doesn't have to be cut down, like wood from forests. It produces clean, green power in the form of electricity and can be used to power just about everything we need. There is more solar energy landing on the earth every day than it would take to supply the world for a year. Solar energy can heat swimming pools, power calcul
boothreb99

Hydrogen's Dirty Secret | Mother Jones - 0 views

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    "Such a system, experts say, would effectively eliminate most of the benefits offered by hydrogen. Although the fuel-cell cars themselves may emit nothing but water vapor, the process of producing the fuel cells from hydrocarbons will continue America's dependence on fossil fuels and leave behind carbon dioxide, the primary cause of global warming."
shortsleevesky99

Fuel Cells - 1 views

  • Current estimates for an entire system, including fuel and air supply, insulation, fuel cells stack, reformer and desulfurizer, piping, labor, depreciation, system control and power electronics is as high as $4000 per kW [20].
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    "The technology for fuel cells has been around since 1839. NASA further developed the technology for the Gemini space project[18],[19]. Fuel cell technology remains in a developmental phase and only in the past ten years has development significantly increased."
shortsleevesky99

FAQ | Fuel Cells 2000 - 0 views

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    "The first fuel cell was built in 1839 by Sir William Grove, a Welsh judge and gentleman scientist, who conducted dozens of experiments using his "gas battery."  More than a century later, equipment manufacturer Allis Chalmers plowed a Wisconsin alfalfa field using fuel cell-powered tractor (1959).  Serious interest in the fuel cell as a practical energy generator did not begin until the 1960′s, when the U.S. space program chose fuel cells over riskier nuclear power and more expensive solar energy, using fuel cells to furnish power for the Gemini and Apollo spacecraft and electricity and water for the space shuttle.  Also in the 1960s, the first passenger vehicle, a prototype van, was built by GM (1966); major auto manufacturers began more concerted fuel cell development efforts in the 1990s."
streetscor99

Fuel cells, what is a fuel cell, disadvantages, benefits - 0 views

  • * Because there is no combustion in a fuel cell, fuel is converted to electricity more efficiently than any other electrical generating technology available today. * There are no moving parts in a fuel cell stack, making them more reliable and quieter than generators. Even the ancillary systems (fans, pumps, controls, etcetera) in a complete fuel cell unit are relatively mature and simple technologies that should prove extremely reliable.
  • In the past, fuel cells were large and extremely expensive to manufacture, just as the first calculators and computers were. But, just like these products, the cost of fuel cells will quickly come down to consumer-affordable levels with mass production. We are currently in a transition period now, where many fuel cell companies are investing literally hundreds of millions of dollars to gear up for mass manufacturing at the same time they are trying to begin to develop a variety of markets for their product.
turnmaster

Geothermal Electric Technology | Whole Building Design Guide - 0 views

  • The conversion technologies from hydrothermal fluids to electricity include flash steam, dry steam, and binary-cycle power plants. Each geothermal electric system is made up of several key components including a: Production well Turbine Generator Injection well. Dry steam power plants are the simplest and oldest design, upon which the two other systems are based. They use a geothermal production well that produces fluid heated by the natural heat of the earth. The steam goes directly to a turbine, which drives a generator that produces electricity. The fluid then goes into an injection well, which is a well that is specifically drilled for the safe disposal of the geothermal fluids.
boothreb99

Group items matching "fuel cell" in title, tags, annotations or url - qmstech2 | Diigo ... - 1 views

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    "The fuel cell is being considered as an eventual replacement for the internal combustion engine for cars, trucks and buses. Major car manufacturers have teamed up with fuel cell research centers or are doing their own development. There are plans for mass-producing cars running on fuel cells. Because of the low operating cost of the combustion engine, and some unresolved technical challenges of the fuel cell, however, experts predict that a large scale implementation of the fuel cell to power cars will not occur before 2015, or even 2020."
stockmanchl99

History of BioFuel | www.stillisstillmoving.com - 0 views

  • Fueling up with ethanol and vegetable oils  was common long before the development of the internal combustion engine. Vegetable and animal oil lamps have been used since the dawn of civilization. Increasingly efficient heaters and lamps meant that higher quality fuels were developed.  For example, small alcohol stoves (also called “spirit lamps”) were commonly used by travelers in the 17th century to warm food and themselves. One of Ben Franklin’s spirit lamps is on display in a Philadelphia exhibit.
  • Fueling up with ethanol and vegetable oils  was common long before the development of the internal combustion engine. Vegetable and animal oil lamps have been used since the dawn of civilization. Increasingly efficient heaters and lamps meant that higher quality fuels were developed.  For example, small alcohol stoves (also called “spirit lamps”) were commonly used by travelers in the 17th century to warm food and themselves. One of Ben Franklin’s spirit lamps is on display in a Philadelphia exhibit.
  • At the end of WWI, gasoline quality was declining, and Detroit dropped the standard compression ratio to 3.8 to one. According to Scientific American in 1919, there were to options. One, lower the compression ratio even further, sacrificing efficiency but allowing the continued use of low-grade petroleum.  Or two, use more ethanol in the fuel mix in order to conserve petroleum and allow the creation of more efficient, higher compression engines.  The choice was further skewed in the direction of ethanol when the US Geological Survey announced, in 1920, that oil was running out.[20]
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    "Around the 1850s, lamp fuels in the US and Europe were usually made from animal and vegetable oils, often combined with alcohol.  "Camphene" (a camphor oil scented blend of turpentine and ethanol) was by far the leading fuel in the US with at least 90 million gallons sold per year.[14] But a tax on all alcohol in the US, including industrial alcohol for lamps, meant that other sources of illuminants were needed.  The kerosene industry arose as a direct result of this tax on its competitor - and not because whales were running out, as the "whale oil" myth would have it. "Kerosene" was named as the solar (keros) fuel in imitation of  "camphene." The highly volatile byproduct, called "gasoline" in the hope it would be used in municipal gas light systems, was usually blended unsafely into lamp fuels, or just poured into streams or burned off."
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