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Generate Your Own Wind Energy - 0 views

  • As with installing your own solar energy, installing wind energy will help to reduce carbon emissions, which damage the environment and will save money.
  • It's only downfall is possibly the visual impact it makes on the landscape: A tall 'small scale' generator could attract wide rebuttal from neighbours, and this is worth considering before embarking on a wind generation project. However, if you live in a remote area, which benefits from exposure to the wind, or have neighbours that are happy for you to go ahead with the project, installing wind power can be an economically viable way to capitalise on natural, renewable resources
  • A wind generator will cost in the region of £3'000 - £15'000, at about £3'000 per kilowatt.
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  • You can expect a wind generator to pay for itself in little over five years, and with conventional energy prices soaring, the dividends will increase with time.
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Wave Energy Pros and Cons - Energy Informative - 0 views

  • Harnessing wave energy comes without the emission of harmful green house gases. This is the main motivation factor behind further development of this way of power generation.
  • Like with most green energy sources, wave power is also renewable. Since this energy source ultimately comes from the heat energy that is emitted from the sun, it will not disappear for some time – in fact, several billion years or as long time it takes for the sun to burn out.
  • The energy density is typically around 30-40 kW for every meter (2.2 feet) of wave along the shore. As we go further into the ocean 100kW for every meter is not uncommon.
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  • Waves are hardly interrupted and almost always in motion.
  • This makes generating electricity from wave energy a reasonable reliable energy source
  • It should be mentioned that the amount of energy that is being transported through waves does vary every year and from season to season. On the northern hemisphere, the average value of November and May could be different with a factor of two or more.
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EnergyBC: Tidal Power - 2 views

  • his is somewhat balanced out by long plant lives of 100 years for the actual barrage structure, and 40 for the equipment, as well as low operating costs.
  • An estimate is given by researcher Eleanor Denny. Denny estimates that in order for a facility to be profitable, its capital cost should be less than €530,000 (~$700,000 USD) per MegaWatt which with the current technology is not a realistic goal, meaning that so far the industry produces negative net benefits.50
  • Canada's Race Rocks site, where a single turbine generator converts 65 kW of energy, cost $4,000,000.54 This figure was met with $3,000,000 investment from project partner EnCana's Environmental Innovation Fund, and a grant of just under $1 million awarded to Pearson College and their partners in the project.
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  • This plant produces about 100 times the power generated at Race Rocks. An investment of around €8.5 million ($11 million USD) made SeaGen a reality.
  • The environmental impacts of tidal barrage include hampered fish migration, forced water level changes on the basin behind the barrage, reduced salinity in the basin due to low quantities of ocean water, and reduced ability of currents to transport and suspend sediments
  • sustainable energy resources produce limited amounts of carbon dioxide emissions
  • , they are, by nature, reliant on the natural environment and therefore are vulnerable to the effects of climate change
  • Brief History of Tidal Power The energy stored in tides been known to people for many centuries. The earliest records of tidal mills are dated back to the 8th Century CE.7 The tidal mills were mainly used for grain grinding and were of similar design to the conventional water mills with the exception of the addition of a dam and reservoir. The industrial revolution increased demand for power but tidal energy never got off the ground, undercut by cheap fossil fuels and other developments which offered easier access to power generation. Existing tidal mills became as obsolescent as pre-industrial water-mills. The first large scale modern tidal electric plant started to operate in La Rance Estuary, St. Malo, France in the 1960s and has been operating ever since. In recent years the search for renewable, non-polluting energy sources and the increase in fossil fuel prices has encouraged renewed interest in tidal power.
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Tidal power - Wikipedia, the free encyclopedia - 0 views

  • idal power is taken from the Earth's oceanic tides; tidal forces are periodic variations in gravitational attraction exerted by celestial bodies. These forces create corresponding motions or currents in the world's oceans
  • Because the Earth's tides are ultimately due to gravitational interaction with the Moon and Sun and the Earth's rotation, tidal power is practically inexhaustible and classified as a renewable energy resource
  • Because the Earth's tides are ultimately due to gravitational interaction with the Moon and Sun and the Earth's rotation, tidal power is practically inexhaustible and classified as a renewable energy resource
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    ware tide energy comes from     
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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.
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tidal energy - 0 views

  • Tidal energy is the utilization of the variations in sea level caused primarily by the gravitational effects of the moon, combined with the rotation of the Earth.
  • Tidal energy is a clean, renewable energy resource, but its environmental impacts and accessibility, limit its potential to become a major provider of electricity. Where tidal energy is a viable resource, it may prove to be expensive at first, but economical in the long run if the technology improves.
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Montana Environmental Information CenterCost of Wind vs. Fossil Fuels - MEIC - 0 views

  • Wind energy is cost-competitive with fossil fuels, especially coal. In Montana, wind energy is less expensive than coal for NorthWestern Energy--the state's largest utility.
  • ccording to the EIA, the total cost of wind energy without federal tax and other financial incentives is about 9.7 cents/kilowatt-hour. The total cost of conventional coal without federal tax and other financial incentives is about 9.4 cents/kilowatt-hour.
  • here are integration costs associated with intermittent renewable energy but unlike fossil fuels, wind (and solar and many other renewables) the fuel price stays the same: Zero.  Plus, wind-power technology has rapidly evolved. Turbines are much larger, growing from an average of 1.2 megawatts to 1.6 megawatts (a 33% increase in average capacity) in just three years.
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  • When comparing the cost of wind vs. fossil fuels its important to consider  fuel costs, integration costs, operating costs, and the cost of tax incentives. Wind energy is cost-competitive with fossil fuels, especially coal. In Montana, wind energy is less expensive than coal for NorthWestern Energy--the state's largest utility. The graph below from the Montana Public Service Commission, compares the costs of various resources in NorthWestern's portfolio. Judith Gap wind facility is about $47.00/Megawatt-hour (or 4.7 cents/kilowatt-hour) and Colstrip Unit 4 is $68.00/Megawatt-hour or (6.8 cents/kilowatt hour).
  • Today's typical new turbine has a 2.3-megawatt capacity; 7-megawatt turbines will be available soon.  The newer turbines can wring more electric power out of the wind (especially at lower wind speeds) than older turbines could. The combination of greater output and greater capacity nearly offsets the materials and labor cost increases plaguing traditional resources.
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    wind to fossil fuels 
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Energy Resources: Biofuels - 2 views

  • By "biofuels" on this page, I mean fuels for vehicles, such as "biodiesel" and "bioethanol" - although you can also use the term "biofuel" to cover any kind of fuel made from living materials or their waste.
  • How it works Biofuels are made from two main sources: Growing crops such as corn, sugar cane, soya or rapeseed; or from palm oil Growing algae
  • Biofuels are made from two main sources: Growing crops such as corn, sugar cane, soya or rapeseed; or from palm oil Growing algae
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  • iofuels are potentially carbon-neutral, because although carbon dioxide is released when we burn them, carbon dioxide is taken in by the plants as they grow. However, energy is needed to grow the crops, harvest them, and to process the results into usable products - and most of this energy will be from fossil fuels for farm machinery and power stations.
  • Biofuels are potentially carbon-neutral, because although carbon dioxide is released when we burn them, carbon dioxide is taken in by the plants as they grow. However, energy is needed to grow the crops, harvest them, and to process the results into usable products - and most of this energy will be from fossil fuels for farm machinery and power stations.
  • Producing biofuels from crops means using large amounts of land to grow those crops - that means less land for food production. We must be careful to strike a balance between crops ofr fuel and crops for food.
  • Producing biofuels from crops means using large amounts of land to grow those crops - that means less land for food production. We must be careful to strike a balance between crops ofr fuel and crops for food.
  • Algae - that's pond scum - are microscopic water plants. They reproduce and photosynthesise fast, and the algae are then filtered out of the water and the lipids (oils) are used to make biodiesel.
  • It is claimed that growing plants to make biofuels will take in that carbon dioxide again. But biologists tell us that forests are not 'the lungs of the planet' after all - they give out as much CO2 as they absorb as the plants respire. It seems that it's plant plankton in the oceans that takes in most CO2 and gives out most oxygen.
  • It takes huge areas of land in order to grow crops for biofuels, although making biofuels from algae does not have this problem
  • Biofuel production is closer to being carbon-neutral than using fossil fuels.
  • Is it renewable? Biofuels are renewable, we can plant more of the crops or grow more of the algae.
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Fossils Fuels vs. Renewable Energy | Ecology Global Network - 1 views

  • Burning fossil fuels creates carbon dioxide, the number one greenhouse gas contributing to global warming. Combustion of these fossil fuels is considered to be the largest contributing factor to the release of greenhouse gases into the atmosphere. In the 20th century, the average temperature of Earth rose 1 degree Fahrenheit (1°F). This was a period that saw the most prolific population growth and industrial development
  • Some estimates say our fossil fuel reserves will be depleted within 50 years, while others say it will be 100-120 years.
  • Sun, wind and water are perfect energy sources…depending on where you are. They are non-polluting, renewable and efficient
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  • The object is to capture and harness their mechanical power and convert it to electricity in the most effective and productive manner possible.
  • Another form of hydroelectric energy is tidal power. In use since the early 1900s, tidal power stations collect the energy created by the rise and fall of the tides to convert to electricity.
    • mannixjul00
       
      history maybe?
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Energy Resources: Tidal power - 1 views

  • Advantages Once you've built it, tidal power is free. It produces no greenhouse gases or other waste. It needs no fuel. It produces electricity reliably. Not expensive to maintain. Tides are totally predictable. Offshore turbines and vertical-axis turbines are not ruinously expensive to build and do not have a large environmental impact. Disadvantages A barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed. Fish can't migrate, unless "fish ladders" are installed. Only provides power for around 10 hours each day, when the tide is actually moving in or out. There are few suitable sites for tidal barrages Is it renewable? Tidal energy is renewable. The tides will continue to ebb and flow, and the energy is there for the taking.
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What are the advantages and disadvantages of alternative tidal power as an energy source - 1 views

  • Advantages: Tidal energy is an alternative energy. The energy produced is clean and non polluting. There is no carbon dioxide or any other by-products released. It produces no greenhouse gases or other waste.It is a renewable energy that will help reduce our reliance on the burning of fossil fuels. There are two tides every day and they can be relied on. The energy is there for the taking.So the electricity supply is constant and efficient.Once you've built it, the energy is free because it comes from the ocean's powerIt needs no fuel.It produces electricity reliably.Not expensive to maintain.Tides are definitely predictable. There are two tides every day and they can be relied on. So the electricity supply is constant. Offshore turbines and vertical-axis turbines are not ruinously expensive to build and do not have a large environmental impact.A plant is expected to be in production for 75 to 100 yearsUses an abundant, inexpensive fuel source (water) to generate powerMay protect coastline against damage from high storm tides and provide a ready-made road bridge
  • Holding back the tide allows silt to build up on the river bed.The dams and barrages sometimes interfere with shipping. You will need to find a way to connect the electricity to the grid.Pose same threats as large dams, altering the flow of saltwater in and out of estuaries, which changes the hydrology and salinity and possibly negatively affects the marine mammals that use the estuaries as their habitatTurbidity decreases as a result of smaller volume of water being exchanged between the basin and the sea.The average salinity inside the basin decreases, also affecting the ecosystemA barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed.There are few suitable sites for tidal barrages.Only provides power for around 10 hours each day, when the tide is actually moving in or out.
  • It only provides about 7% of the power needed for England and Wales that means that some people get their energy close to free and some pay a lot of moneyWater is not replenished, it cannot flow away so any dirt or pollution lingers around the coast much longerNeeds a very big piece of sea to be cost effectiveCannot be used inlandBarrage systems require salt resistant parts and lots of maintenanceAffects the lives of the people who rely on fishing for a means of livingLimited because the tide never speeds up or slows down, and occurs on 6 hour cycles. It is also dependent on the fetch distance. The fetch is the distance the tide rises and falls, so some beaches have a very small fetch, and others have a big fetch but hardly any have a large enough fetch to support tidal energy
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Wave Power - Energy from ocean surface waves - 1 views

  • Wave energy is produced when electricity generators are placed on the surface of the ocean
  • Energy output is determined by wave height, wave speed, wavelength, and water density.
  • The energy provided is most often used in desalination plants, power plants and water pumps.
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  • The energy provided is most often used in desalination plants, power plants and water pumps.
  • Just like wind mills and wind turbines that generate power and electricity from the wind, scientists are now working to generate power from the sea
  • Wave energy is among the impressive list of renewable energy resources that is being developed in the United States.
  • Ocean wave energy can be captured directly from surface waves. Blowing wind and pressure fluctuations below the surface are the main reasons for causing waves.
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    Controlling factor of electric power.
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EIA Energy Kids - Geothermal - 3 views

  • Geothermal Basics What Is Geothermal Energy? The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity. Geothermal energy is a renewable energy source because the heat is continuously produced inside the Earth.
  • Geothermal energy is generated in the Earth's core. Temperatures hotter than the sun's surface are continuously produced inside the Earth by the slow decay of radioactive particles, a process that happens in all rocks. The Earth has a number of different layers:
  • Where Geothermal Energy is Found The ring of fire goes around the edges of the Pacific. The map shows that volcanic activity occurs around the Pacific rim.Source: National Energy Education Development Project (Public Domain) Naturally occurring large areas of hydrothermal resources are called geothermal reservoirs. Most geothermal reservoirs are deep underground with no visible clues showing above ground. But geothermal energy sometimes finds its way to the surface in the form of: Volcanoes and fumaroles (holes where volcanic gases are released) Hot springs Geysers
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  • U.S. Geothermal Is Mostly in the West Most of the geothermal reservoirs in the United States are located in the western States and Hawaii.
  • Electricity generation power plants require water or steam at very high temperature (300° to 700°F). Geothermal power plants are generally built where geothermal reservoirs are located within a mile or two of the surface.
  • The United States Is the Leader in Geothermal Power Generation The United States leads the world in electricity generation with geothermal power.  In 2009, U.S. geothermal power plants produced 15 billion kilowatt-hours (kWh), or 0.4% of total U.S. electricity generation.  In 2009, five States had geothermal power plants:
  • Geothermal power plants use hydrothermal resources that have two common ingredients: water (hydro) and heat (thermal). Geothermal plants require high temperature (300°F to 700°F) hydrothermal resources that may come from either dry steam wells or hot water wells.
  • high-pressure hot water from deep inside the Earth and convert it to steam to drive the generator turbines. When the steam cools, it condenses to water and is injected back into the ground to be used over and over again. Most geothermal power plants are flash steam plants.
  • Geothermal Power Plants Have Low Emission Levels Geothermal power plants do not burn fuel to generate electricity, so their emission levels are very low. They release less than 1% of the carbon dioxide emissions of a fossil fuel plant. Geothermal plants use scrubber systems to clean the air of hydrogen sulfide that is naturally found in the steam and hot water. Geothermal plants emit 97% less acid rain-causing sulfur compounds than are emitted by fossil fuel plants. After the steam and water from a geothermal reservoir have been used, they are injected back into the Earth.
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Hydropower: Generate Energy with Rivers and Ocean Tides - For Dummies - 0 views

  • When water flows toward the shore with the incoming tide, it flows through a tidal energy system, turning a turbine that generates electricity. When the tide shifts and flows in the opposite direction, away from shore, the tidal energy system again captures the energy with a turbine and converts it into electricity.
  • An important source of alternative energy is hydropower: converting the flow of rivers and ocean waves and tides into electricity through dams and turbines. The best part about both of these water sources is that they’re 100 percent renewable.
  • The main advantage of using ocean tides for energy is that tides and waves are a constant, unchanging, clean source of energy. The main disadvantage is that tidal energy systems may impact the environment by changing the flow of water into shoreline and estuarine ecosystems.
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NREL: Hydrogen and Fuel Cells Research - Renewable Electrolysis - 0 views

  • Renewable electrolysis is a process that uses renewable electricity to produce hydrogen by passing an electrical current through water. Renewable energy sources such as photovoltaics, wind, biomass, hydropower, and geothermal can provide clean, sustainable electricity for our nation
  • Wind turbines can be used to produce hydrogen through a process called renewable electrolysis.
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Tidal Energy Pros and Cons - Energy Informative - 0 views

  • This ultimately reduces the cost these power plants can sell their electricity
  • It is important to realize that the methods for generating electricity from tidal energy is a relatively are relatively new technologies
  • Tidal Energy is a renewable energy source. This energy source is a result of the gravitational fields from both the sun and the moon, combined with the earth’s rotation around its axis, resulting in high and low tides.
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  • In addition to being a renewable energy, it does not emit any climate gases and does not take up a lot of space
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    pollution
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Biofuel Facts, Biofuel Information - National Geographic - 0 views

  • Biofuels have been around as long as cars have. At the start of the 20th century, Henry Ford planned to fuel his Model Ts with ethanol, and early diesel engines were shown to run on peanut oil.
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    "On the face of it, biofuels look like a great solution. Cars are a major source of atmospheric carbon dioxide, the main greenhouse gas that causes global warming. But since plants absorb carbon dioxide as they grow, crops grown for biofuels should suck up about as much carbon dioxide as comes out of the tailpipes of cars that burn these fuels. And unlike underground oil reserves, biofuels are a renewable resource since we can always grow more crops to turn into fuel. Unfortunately, it's not so simple. The process of growing the crops, making fertilizers and pesticides, and processing the plants into fuel consumes a lot of energy. It's so much energy that there is debate about whether ethanol from corn actually provides more energy than is required to grow and process it. Also, because much of the energy used in production comes from coal and natural gas, biofuels don't replace as much oil as they use. For the future, many think a better way of making biofuels will be from grasses and saplings, which contain more cellulose. Cellulose is the tough material that makes up plants' cell walls, and most of the weight of a plant is cellulose. If cellulose can be turned into biofuel, it could be more efficient than current biofuels, and emit less carbon dioxide. "
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Renewable Energy Sources (4) Wave energy | dnahtigal - 0 views

  • Waves are caused by the action of winds on the sea. Waves can be many metres in height and contain a great deal of energy. This energy can be harnessed to drive turbines that generate electricity.
  • Wave energy collectors are of two main types. The first type directs waves into man-made channels, where the water passes through a turbine that generates electricity. The second type uses the up and down movement of a wave to push air
  • Wave energy can be harnessed in coastal areas, close to the shore. There has been one such device working on the island of Islay in Scotland since the early 1990s, producing 75kW of electricity.
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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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Energy Resources: Wave power - 1 views

  • Ocean waves are caused by the wind as it blows across the sea. Waves are a powerful source of energy.
  • How it works There are several methods of getting energy from waves. One of them works like a swimming pool wave machine in reverse. At a swimming pool, air is blown in and out of a chamber beside the pool, which makes the water outside bob up and down, causing waves.   At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a turbine in this hole, which is turned by the air rushing in and out. The turbine turns a generator.
  • Once you've built a wave power station, the energy is free, needs no fuel and produces no waste or pollution.
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  • Not expensive to operate and maintain.
  • Needs a suitable site, where waves are consistently strong.
  • Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem.
  • Is it renewable? Wave power is renewable.
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