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The Physics of Tidal Energy - NYTimes.com - 0 views

  • a tidal energy project is moving ahead in Maine, with high costs but high hopes too. But the 180-kilowatt unit that the Ocean Renewable Power Company hopes to put under water next week is really just a first step. The big question is, how well will it withstand the force of the rushing water?
  • The region, the Bay of Fundy, is famous for strong tides, but the company has picked a spot called Cobscook Bay, where the current is relatively slow, an average of 5.8 knots, or 6.7 miles an hour. That is the speed at which the hardware will produce 180 kilowatts.
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    How it works, how fast the waves are
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Tidal Energy | Marine Current Turbines - 0 views

  • idal turbines are very much like an underwater windmill where the blades are driven by consistent, fast-moving currents.  The submerged rotors harness the power of the tidal streams to drive generators, which in turn produce electricity. Water is 832 times denser than air so consequently tidal turbine rotors can be are much smaller than wind turbine rotors generate equivalent  amounts of electricity, and they can be deployed much closer together. Devices that harness tidal stream energy present a unique set of engineering challenges in terms of design, installation and maintenance. During operation, the force of the tidal flow in Strangford Lough is equivalent to a 345 mph wind generating a 100 tonnes of thrust on the rotors. The unique SeaGen design allows capture of the maximum amount of tidal energy whilst keeping maintenance and connectivity costs low.
  • Tidal turbines are very much like an underwater windmill where the blades are driven by consistent, fast-moving currents.  The submerged rotors harness the power of the tidal streams to drive generators, which in turn produce electricity. Water is 832 times denser than air so consequently tidal turbine rotors are much smaller than wind turbine rotors generate equivalent  amounts of electricity, and they can be deployed much closer together. Devices that harness tidal stream energy present a unique set of engineering challenges in terms of design, installation and maintenance. During operation, the force of the tidal flow in Strangford Lough is equivalent to a 345 mph wind generating a 100 tonnes of thrust on the rotors.
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    How it works.
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Tidal Energy for Kids - 0 views

  • As far as producing electricity goes, tidal energy is one of the cheapest kinds.
  • Since the tidal cycle repeats itself every 24 hours, there is a guarantee that power can be produced this way every day of the year.
  • can help protect delicate coastal areas from storm damage, as well
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  • can protect against erosion
  • Even though tidal energy does not produce any kind of pollution, the barrages completely change the coastline. Many animals and birds make their homes on the mudflats around tidal basins. When the tidal energy plants flood these areas, the habitats of these animals are destroyed. Holding the water back also causes silt to build up inside the tidal basin and can cause the released water to take longer to clear from dirt and materials. This can keep the water around the coastline from settling and becoming clear as quickly as it usually does. There is also evidence that using tidal power plants can change the migration patterns of many ocean creatures.
  • Other people think that since tidal energy plants can only produce electricity for about ten hours every day,
  • it is not worth the danger to plants, animals, and ecosystems.
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Distributed Wind - 0 views

  • The U.S. leads the world in the production of small wind turbines, which are defined as having rated capacities of 100 kilowatts and less, and the market is expected to continue strong growth through the next decade.
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Wind Power Information, Wind Power Facts - National Geographic - 1 views

  • Wind is a clean source of renewable energy that produces no air or water pollution.
  • Wind is the movement of air from an area of high pressure to an area of low pressure. In fact, wind exists because the sun unevenly heats the surface of the Earth. As hot air rises, cooler air moves in to fill the void. As long as the sun shines, the wind will blow. And as long as the wind blows, people will harness it to power their lives.
  • The wind spins the blades, which turn a shaft connected to a generator that produces electricity. Other turbines work the same way, but the turbine is on a vertical axis and the blades look like a giant egg beater.
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  • At the end of last year, global capacity was more than 70,000 megawatts.
  • And since the wind is free, operational costs are nearly zero once a turbine is erected.
  • Globally, generation more than quadrupled between 2000 and 2006.
  • n the energy-hungry United States, a single megawatt is enough electricity to power about 250 homes.
  • ndustry experts predict that if this pace of growth continues, by 2050 the answer to one third of the world's electricity needs will be found blowing in the wind.
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    where wind energy come from
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    ". At the end of last year, global capacity was more than 70,000 megawatts. In the energy-hungry United States, a single megawatt is enough electricity to power about 250 homes. "
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Global Warming And Your Car | Car Talk - 0 views

  • Burning one gallon of gas creates 20 pounds of carbon dioxide, and the average car emits about six tons of carbon dioxide every year
  • So... let's accept that global warming is caused by greenhouse gasses, chief among them carbon dioxide. Cars emit carbon dioxide as part of their emissions...
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Nuclear Industry Withers in U.S. as Wind Pummels Prices - Bloomberg - 0 views

  • The wind power boom has benefited consumers in regions where wind development is fastest, contributing to a 40 percent wholesale power-price plunge since 2008
  • U.S. wind installations have risen 10-fold since 2003 to 60,007 megawatts,
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Tidal Power - Costs - Pros & Cons - How it Works - Green Energy - 0 views

  • Tidal power is a predictable source of energy unlike that of wind power and solar power because the tides follow the gravitational pull of the moon. The general production of tidal energy is similar to other forms of hydroelectric power where the force of water flow spins a turbine which generates energy.
  • he tidal stream generator uses the kinetic energy of the flowing tide to spin windmill like turbines. It is also often referred to as a tidal energy converter (TEC).
  • Tidal power is the production of electricity by the utilization of tidal energy.
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Advantages and Disadvantages of Biofuels - 0 views

  • Biofuels have the potential to be significantly less expensive than gasoline and other fossil fuels. This is particularly true as worldwide demand for oil increases, oil supplies dwindle, and more sources of biofuels become apparent.
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    Biofuels have the potential to be significantly less expensive than gasoline and other fossil fuels. This is particularly true as worldwide demand for oil increases, oil supplies dwindle, and more sources of biofuels become apparent.
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Wave Power - 1 views

  • The World Energy Council has estimated that approximately 2 terawatts (2 million megawatts), about double current world electricity production, could be produced from the oceans via wave power.
  • Wave energy is generally considered to be the most concentrated and least variable form of renewable energy. It is the high power density of wave energy that suggests it has the capacity to become the lowest cost renewable energy source.
  • Wave energy is a renewable, zero emission source of power
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Biofuels | BP - 0 views

  • Biofuels
  • We are working to produce biofuels that are low cost, low carbon, sustainable and able to fulfil the world’s transportation fuel needs on a large scale without compromising food production
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Solar energy 'cheaper than fossil fuels in 5 years' - 0 views

  • Speaking to Silicon.com, the author of The Age of Intelligent Machines, said that nanotechnology could help solve the world's energy crisis and make solar technology cheaper.
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Sustainable energy - Wikipedia, the free encyclopedia - 1 views

  • Sustainable energy is the sustainable provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs.
  • Sustainable energy is the sustainable provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs.
  • Sustainable energy is the sustainable provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs. Technologies that promote sustainable energy include renewable energy sources, such as hydroelectricity, solar energy, wind energy, wave power, geothermal energy, and tidal power, and also technologies designed to improve energy efficiency.
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  • At this rate, many experts believe that solar energy is not efficient enough to be economically sustainable given the cost to produce the panels themselves.
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Wind Energy - 0 views

  • Cons:
  • The purchase and set-up of wind turbines can be expensive
  • Wind turbines require certain constant speeds to be productive (13 mph for large turbines, 9 mph for small turbines)
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  • Wind farms can't sustain constant power due to daily and seasonal variance in wind
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2 studies conclude that biofuels are not so green after all - The New York Times - 0 views

  • most all biofuels used today cause more greenhouse gas emissions than conventional fuels if the pollution caused by producing these "green" fuels is taken into account, two studies published Thursday have concluded.
  • The benefits of biofuels have come under increasing attack in recent months as scientists have evaluated the global environmental cost of their production. The new studies, published by the journal Science, are likely to add to the controversy.
  • When you take this into account, most of the biofuel that people are using or planning to use would probably increase greenhouse gasses substantially," sai
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  • t even that equation proved overly simplistic because the process of turning plants into fuel causes it own emissions - through refining and transport, for example
  • If vegetable oil prices go up globally, as they have because of increased demand for biofuel crops, new land is inevitably cleared as farmers in developing countries switch production. Crops from old plantations and fields go to Europe for biofuels, but new fields and plantations are created to feed people at home.
    • pettitmat99
       
      GR8 info on pollution of biofuels
  • ut the new studies suggested that when land use is taken into account few, if any biofuels, will be acceptable.
  • d: "If the whole point of biofuels directives was to reduce greenhouse gas emissions, we've found out that most biofuels are not really better than conventional fuels at that."
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Tidal Wave Energy - Quick Guide to Costs,Investment and How Tidal Generators Produce Ti... - 1 views

  • .In this form of Tidal Power,a Barrage is built near the coast where water is collected during the periods of high tides.During low tide the barrage allows the water from the reservoir to move towards the ocean or sea.The potential energy of the water at a higher level is converted to electricity using Turbines.
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Group items matching "change future" in title, tags, annotations or url - qmstech2 | Di... - 0 views

  • We are working to produce biofuels that are low cost, low carbon, sustainable and able to fulfil the world’s transportation fuel needs on a large scale without compromising food production
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