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mannixjul00

How Does Tidal Energy Work - 0 views

  • Tidal turbines use similar technology to wind turbines, although their blades are much shorter and stronger. So a good way to think of them is as underwater windmills. Basically the water currents turn the turbines, which in turn activate a generator that produces electricity. These systems work best where there are very strong tidal zones (Norwegian and British coastlines.) and although it is still in it’s infancy it does show great promise.The upfront cost of these tidal stream systems is very high and also installation and maintenance is difficult.
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    "Tidal turbines use similar technology to wind turbines, although their blades are much shorter and stronger. So a good way to think of them is as underwater windmills. Basically the water currents turn the turbines, which in turn activate a generator that produces electricity. These systems work best where there are very strong tidal zones (Norwegian and British coastlines.) and although it is still in it's infancy it does show great promise. The upfront cost of these tidal stream systems is very high and also installation and maintenance is difficult."
dpurdy

Photovoltaic publications : Global Market Outlook, Solar Generation - 1 views

  • On a global scale, approximately 15,000 MW of new PV installations have been added during 2010, amounting the entire PV capacity to almost 40,000 MW.
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    During 2010, the Photovoltaic (PV) market has shown unprecedented growth and wide-spread deployment of this environmentally friendly source of power generation. On a global scale, approximately 15,000 MW of new PV installations have been added during 2010, amounting the entire PV capacity to almost 40,000 MW.
sokolkyl00

Solar Power Energy Information, Solar Power Energy Facts - National Geographic - 0 views

  • Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
  • In one technique, long troughs of U-shaped mirrors focus sunlight on a pipe of oil that runs through the middle. The hot oil then boils water for electricity generation. Another technique uses moveable mirrors to focus the sun's rays on a collector tower, where a receiver sits. Molten salt flowing through the receiver is heated to run a generator.
  • Despite the drawbacks, solar energy use has surged at about 20 percent a year over the past 15 years, thanks to rapidly falling prices and gains in efficiency. Japan, Germany, and the United States are major markets for solar cells. With tax incentives, solar electricity can often pay for itself in five to ten years.
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  • Solar energy is lauded as an inexhaustible fuel source that is pollution and often noise free. The technology is also versatile.
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    " Today, the technology produces less than one tenth of one percent of global energy demand."
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    Intriguing facts about the suns energy on how they use it on oil and the drawback 
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    Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
smithkai143

Re: How is tidal power converted to electricity? - 0 views

  • Tidal Energy originates from gravitational energy. Imagine you have a damn- like structure built along a river. During the high tide, the water flows into the river, causing the turbine to rotate and thus generating electricity. During the low tide, the water flows from the river to the sea, again, turning the turbine. (An electricity generating turbine consists of rotating wires surrounded by strong fixed magnetic field)
smithkai143

What environmental benefits does tidal energy have compared to the traditional fossil f... - 0 views

  • A benefit is very little pollution. However, there is a very serious potential draw back. It can be very hard of fish populations. The proposal for tidal power is to put turbines on the bottom of a bay and let the water rushing in and out with the tide turn them and generate electricity. However, along with the water will come fish and other marine animals. What do you think will happen when these critters get sucked into the turbines. Can you say sushi, boys and girls? Putting some kind of screen in front of the turbine to prevent this would just mean that the animals would be sucked up against the screens, obstructing the flow of water through the turbines.
phinneycha99

Energy and kids - 1 views

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    "Photovoltaic cells, like batteries, generate direct current (DC) which is generally used for small loads (electronic equipment).  When DC from photovoltaic cells is used for commercial applications or sold to electric utilities using the electric grid, it must be converted to alternating current (AC) using inverters, solid state devices that convert DC power to AC. "
phinneycha99

Photoelectric effect - Wikipedia, the free encyclopedia - 0 views

  • In the photoelectric effect, electrons are emitted from matter (metals and non-metallic solids, liquids or gases) as a consequence of their absorption of energy from electromagnetic radiation of very short wavelength and high frequency, such as ultraviolet radiation.
  • Light–matter interaction Low-energy phenomena: Photoelectric effect Mid-energy phenomena: Thomson scattering Compton scattering High-energy phenomena: Pair production
smithree98

http://www.nrel.gov/docs/fy06osti/39534.pdf - 0 views

    • smithree98
       
      chart that says how much energy hydrogen produces
    • smithree98
       
      not just hydyogen
phinneycha99

The Energy of Light - Lesson - www.TeachEngineering.org - 0 views

  • Visible light is only one type of EM wave. We use different kinds of electromagnetic waves for many different purposes.
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    light is electromagnetic radiation.
smithree98

Fuel cell - Wikipedia, the free encyclopedia - 1 views

  • There were 140,000 fuel cell stacks shipped globally in 2010
  • although, as of 2010, no public company in the industry had yet become profitable
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    actually a pretty decent site to find info on hydrogen
dpurdy

Wave power conversion systems for electrical energy production | Leonardo ENERGY - 1 views

  • Sea waves have associated a form of renewable energy which can be captured by using a hydro mechanical device that in turn drives an electrical generator to produce electrical energy.
schmettererdav00

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.
dpurdy

Wave Hub wave energy hydropower infrastructure project on track for summer 2011 deploym... - 0 views

  • Hartlepool-based JDR Cable Systems is constructing the armored 25- kilometer subsea cable that will connect Wave Hub to the grid and the hub structure that will sit on the seabed. Work also is progressing on the hub assembly, which will provide a connection between the main cable from the shore and the tails leading to the wave energy devices.
dpurdy

Devices that Harness Wave Energy | Wave Energy Cost - 0 views

  • Because wave energy needs only 1/200 the land area of wind and requires no access roads, infrastructure costs are less;
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    "7. Because wave energy needs only 1/200 the land area of wind and requires no access roads, infrastructure costs are less;"
dpurdy

Wave Energy: an Overview (Oxfordshire Climate Exchange) - 1 views

  • Waves are generated by winds blowing over the ocean surface.  Wave energy is effectively a stored and concentrated form of solar energy since the winds that produce them are caused by pressure differences in the atmosphere caused by the sun's differential heating of the earth's surface. Waves can efficiently transport energy for thousands of miles and retain their energy long after the winds that first created them have died down, which makes waves one of the most concentrated and consistent sources of renewable energy. 
  • Globally, the potential use of wave power is, unsurprisingly, limited to areas of the world where there are waves. On a global scale, this is dictated by global wind patterns, with the result that waves are more prevalent in the mid-latitudes (40-60(N/S), than nearer the equator where the lack of ocean wind is referred to as the 'doldrums'.  Interestingly, this potential for wave power contrasts with that of solar power, which is more effective in lower latitudes
    • dpurdy
       
      Location of wave power.
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  • it is widely anticipated that other types of renewable resources, including wave energy, will need to be developed in order to meet more challenging targets beyond 2020. 
  • As with most renewable energy sources, wave devices have no emissions during generation but the energy associated with the construction of the device does have small associated emissions.
    • dpurdy
       
      What do we need to do in the future to make this work.
  • it is essential that the current demonstration schemes are successful, to reassure future investors. The most important objective is to deploy full-size demonstration schemes in order to gain greater confidence in the most developed technologies (as in the EU's Atlas project). 
  • it will be necessary to significantly improve the network connections to the electricity suppliers.
dpurdy

How we know human activity is causing warming | Environmental Defense Fund - 1 views

  • The theory of global warming is nothing new. The Nobel Prize-winning chemist Svante Arrhenius first proposed the idea of global warming in 1896. Carbon dioxide, he knew, traps heat in the Earth's atmosphere. He also knew that burning coal and oil releases carbon dioxide (CO2).
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