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tidal energy steps to electricity - Google Search - 1 views

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    "Mills using tidal power can be dated back to 12th century Europe, a technology that followed colonists to the Americas."
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STELR :: wind ENERGY - 1 views

  • STEP 1: Moving air pushes against the blades of the turbine, which are tilted to the direction of the wind. This makes the blades spin. In the process, some of the kinetic energy of the moving air is transformed into the mechanical energy of the spinning blades. (The wind still has some kinetic energy as it flows away from the turbine.) STEP 2: The shafts and the gears inside the gear box transfer the mechanical energy of the turbine to the generator. (The gears make the drive shaft to the generator spin faster than the shaft connected to the blade hub.) STEP 3: The generator transforms mechanical energy into electrical energy.
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    steps to converting win power to electricty
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STEP - Heating houses by sunlight-How sustainable is solar power generally? - 0 views

  • Solar energy does little to harm the environment.
  • Even when the sun does not shine because of cloud or dust, its diffuse rays can still be used to produce electricity or heat.
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Tidal Energy Ltd » The Technology - 0 views

  • Tidal energy is a form of hydropower that converts the energy of the tides into electricity or other useful forms of power. The tide is created by the gravitational effect of the sun and the moon on the earth. Tidal energy is therefore a predictable form of renewable energy, which can be harnessed in two forms:
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    what it is.
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Tidal Power - 1 views

  • Tidal power is a means of electricity generation achieved by capturing the energy contained in moving water mass due to tides. Two types of energy can be extracted: kinetic energy of currents between ebbing and surging, and potential energy from the difference in height (or head) between high and low water marks.
  • Tidal power schemes do not produce energy 24 hours a day. A conventional design, in any mode of operation, would produce power for 6 to 12 hours in every 24 and will not produce power at other times
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Five Reasons Why Tidal Energy is the Wave of the Future - Green Living Ideas - 3 views

  • Green energy has never been more important than it is today with the looming threat of global warming. Every possible effort must be made to reverse the worldwide threat of climate change by subsidizing and switching to green energy. One often-overlooked source of clean, renewable energy comes not from solar, wind or geothermal power, but from the tides.
  • Tidal Energy is valuable to environmentalists because unlike fossil fuels the source of energy will not be depleted in the foreseeable future no matter how much energy is collected.
  • The collection of tidal energy is clean because it involves very little emission of carbon dioxide and other greenhouse gases
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  • The pattern of tides is extremely stable and not strongly affected by weather conditions which suggests that it would be a very stable source of green energy.
  • Moving water can exert a much greater force on a turbine than wind which means the turbine can turn slowly and still produce a great deal of electricity. The slow and stable tidal forces are ideal parameters for engineering energy solutions. The fact that the turbines can be slow-moving makes it easier to avoid interfering with local ecosystems
  • While the initial cost of building tidal energy plants is high, the plants are expected to run for a very long time which will make them more cost-effective in the long run
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    "Five Reasons Why Tidal Energy is the Wave of the Future JANUARY 4, 2013 BY GUEST CONTRIBUTOR LEAVE A COMMENT Join GLI's 10,000 other followers on Twitter! Green energy has never been more important than it is today with the looming threat of global warming. Every possible effort must be made to reverse the worldwide threat of climate change by subsidizing and switching to green energy. One often-overlooked source of clean, renewable energy comes not from solar, wind or geothermal power, but from the tides. 1. Tidal Energy is Renewable Tidal Energy is valuable to environmentalists because unlike fossil fuels the source of energy will not be depleted in the foreseeable future no matter how much energy is collected. The gravitational relationship between the Earth and the moon is extremely stable in the long term just like solar, wind and geothermal energy. 2. Tidal Energy is Green The collection of tidal energy is clean because it involves very little emission of carbon dioxide and other greenhouse gases. However, the marine ecosystem is fragile and great care must be taken to avoid interfering with the lives of organisms that depend on the tide."
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Wind Power - What is Wind Power and How Does It Work? - 0 views

  • wind power as a better way to generate electricity than plants fueled by coal, hydro (water) or nuclear power.
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    "Wind power is actually a form of solar power, because wind is caused by heat from the sun. Solar radiation heats every part of the Earth's surface, but not evenly or at the same speed. Different surfaces-sand, water, stone and various types of soil-absorb, retain, reflect and release heat at different rates, and the Earth generally gets warmer during daylight hours and cooler at night. As a result, the air above the Earth's surface also warms and cools at different rates. Hot air rises, reducing the atmospheric pressure near the Earth's surface, which draws in cooler air to replace it. That movement of air is what we call wind."
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    what is wind power
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How does tidal energy generate electricity - 0 views

  • Tidal BarragesA tidal barrage is basically a huge dam that is built across a river or estuary. Tunnels are built throughout the dam, and when the tide rises and falls it turns a turbine that generates power. Tidal FencesTidal fences are giant turnstiles that have vertical axis turbines mounted on a fence. The water passes through the fence and powers the turbines. Tidal TurbinesTidal turbines are the latest water power technology used in tidal areas. They look like wind turbines that are lined together underwater. They are used to capture strong tidal flows, so they have to be built extra strong.
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History of wind power - Wikipedia, the free encyclopedia - 0 views

  • The first windmills in Europe appear in sources dating to the twelfth century. These early European windmills were sunk post mills. The earliest certain reference to a windmill dates from 1185, in Weedley, Yorkshire, although a number of earlier but less certainly dated twelfth century European sources referring to windmills have also been adduced.
  • The first windmill used for the production of electricity was built in Scotland in July 1887 by Prof James Blyth of Anderson's College,
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The Energy Story - Chapter 15: Solar Energy - 1 views

  • We have always used the energy of the sun as far back as humans have existed on this planet. As far back as 5,000 years ago, people "worshipped" the sun. Ra, the sun-god, who was considered the first king of Egypt.
  • We have always used the energy of the sun as far back as humans have existed on this planet. As far back as 5,000 years ago, people "worshipped" the sun.
  • Ra, the sun-god, who was considered the first king of Egypt
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  • When sunlight strikes the solar cell, electrons (red circles) are knocked loose. They move toward the treated front surface (dark blue color). An electron imbalance is created between the front and back. When the two surfaces are joined by a connector, like a wire, a current of electricity occurs between the negative and positive sides. These individual solar cells are arranged together in a PV module and the modules are grouped together in an array. Some of the arrays are set on special tracking devices to follow sunlight all day long.
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    the sun
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Unearthing the True Cost of Fossil Fuels : TreeHugger - 0 views

  • “true” cost of coal: Depending on how you factor in the costs of climate change, it could be between a few additional cents per kWh to a whopping ¢26.89 extra per kilowatt hour—the high-end estimate from the Harvard study. By way of comparison, the average American paid ¢11.54 per kWh on their residential electric bills last year.
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How Do PV Solar Panels Work - Solar - 0 views

  • When a visible light photon strikes a solar cell it can do one of three things: pass straight through, be reflected, or be absorbed. If the photon is absorbed, its energy is absorbed by an electron in an atom of the solar cell enabling it to escape from its normal position (photon excitation), cross the junction and fill a hole. Since electrons are physically moving across the PN junction, the positive charge carrying holes are effectively moving in the opposite direction around the load circuit (a rechargeable battery or light bulb etc). This completes the circuit providing more holes for the electrons to combine with and providing usable electricity.
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How Wind Works | Wind Energy Foundation - 0 views

  • Wind is simply air in motion. It is caused by the uneven heating of the Earth's surface by the sun. Because the Earth's surface is made of very different types of land and water, it absorbs the sun's heat at different rates. One example of this uneven heating can be found in the daily wind cycle.
  • Mechanical or electrical power is created through the kinetic energy of the wind.
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Wind turbine - Wikipedia, the free encyclopedia - 0 views

  • The first electricity-generating wind turbine was a battery charging machine installed in July 1887 by Scottish academic James Blyth to light his holiday home in Marykirk, Scotland.[7
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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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Tidal stream generators - Brightside - 0 views

  • Tidal stream generators look and work like underwater wind turbines. As opposed to using the rising and falling movement of the tides, tidal stream generators take advantage of the fast moving sea currents (tidal streams), which flow when tides are moving in and out. These tidal streams cause the turbines to rotate, turning the generators which generate electricity. Tidal stream generators have the advantage of being much cheaper to build, and do not have as much of an environmental impact as a tidal barrage. The turbines turn relatively slowly, hence do not affect sea life. This is different to tidal barrages which can disrupt fish migrating up rivers from the sea.
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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
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      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.
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      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.
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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.
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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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Hydrogen FAQ - 0 views

  • The cost of hydrogen per mile to power a fuel cell electric vehicle is approximately competitive with the cost of gasoline at $2.30/gallon. This assumes that the hydrogen is made by reforming natural gas at the fueling station with existing commercial hydrogen fueling equipment in low production volumes (10 units). With larger scale production, we estimate that hydrogen will cost less per mile than gasoline selling at $1.50/gallon.
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