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cheniermab99

Wind Turbines for Electricity - 1 views

shared by cheniermab99 on 12 Mar 13 - No Cached
  • In 2006, wind power supplied 0.6% of US electricity but reduced CO2 emission from electricity production by a full 1%.
  • What really matters is the cost to society. With current subsidy methods, it costs around 3¢/kWh
  •   One-Time Cost per kW Capacity (usage) Factor Fixed Cost per kWh Variable Cost per kWh Total Cost per kWh Gas Turbine $439 15% 5.2¢ 8.7¢ 13.9¢ Coal $1,338 90% 2.7¢ 1.9¢ 4.5¢ Nuclear $2,180 90% 4.3¢ 0.3¢ 4.6¢ Wind $1,254* 30% 7.5¢ 0.0¢ 7.5¢
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  • as coal is the worst source of CO2. Thirty years from now, wind power might be cutting global GHG emissions by 10%.
westkea00

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.
greenhan99

Spotlight: How Biofuel Is Made - 0 views

  • Alcohol-based biofuels are produced in much the same way as liquor, though, of course with different emphasis. In fact, ethyl alcohol, or ethanol, which is the most commonly used bio-alcohol, is the same type of alcohol that is found in whiskey, vodka, gin, etc.  All of these are based on the fermentation of starches and sugars. The ingredients are gathered, ground up, mixed with water and left to ferment with the help of yeast or other organisms for some period of time (three years for Scotch whiskey!) before it is finally distilled into the final product.
kramerjac99

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
hertznerkar00

Where does wind energy come from? - Alternative Energy - 0 views

  • Most of the wind energy produced  for power needs comes from wind farms, great big windmill type contraptions produce electricity because as the wind blows it turns the blades on a shaft, which powers a generator.
  • Wind energy is mechanical energy, the rotating movement of the blades of the windmill produces electricity through a generator. The wind is formed by the heating and cooling effects of the suns rays, the air rotates in high and low pressure which generates wind. Depending  on the type of wind pressure that is generated,whether it is a cool breeze on your face, different capacity of the strength of wind is formed in different parts of the world, this power goes to producing an effective source of untapped energy, for use by us in the form of heating and lighting.
  • Most of the wind energy produced  for power needs comes from wind farms, great big windmill type contraptions produce electricity because as the wind blows it turns the blades on a shaft, which powers a generator.
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  • Most of the wind energy produced  for power needs comes from wind farms, great big windmill type contraptions produce electricity because as the wind blows it turns the blades on a shaft, which powers a generator.
  • Wind Power is usually split into two types, offshore and land based operations.
greenhan99

The Biofuels FAQs: The Facts About Biofuels: Ethanol - 0 views

  • Biodiesel consumption was much lower, about 250 million gallons in 2006
  • which requires an annual increase in biofuels use to 7.5 billion gallons by 2012.
greenhan99

Biodiesel Fuel Car, Biofuels Car, Biodiesel Fuel | GreenStudentU.com - 0 views

  • using biodiesel fuel reduces carbon dioxide emissions by 78% when compared to regular petroleum fuel.
mchughkon99

World's fist commercial scale tidal energy generator nears completion - 0 views

  • April 4, 2008 Bristol based renewable energy company Marine Current Turbines has completed the first installation phase of the 1.2MW SeaGen Tidal System at Northern Ireland’s Strangford Lough - a site chosen for its combination of fast tidal current and ability to provide shelter from bad weather which may hinder the construction process.
dextereli99

What is the sustainability of solar energy? - Yahoo! Answers - 2 views

  • The will burn for billions of years, it won't run out any time soon. This is sustainable because it will not deplete in the near future. The harder question is if the materials that go into a solar cell are sustainable. They use primarily silicon, which is one of the most abundant materials on earth. But they can also use other things, like metals (copper, silver, gold), and some toxic chemicals (arsenic, cadmium) etc. The sustainability of these materials is questionable. These materials are recyclable, and it is thought 99% of a solar cell can be recycled. But the production of them does has some toxic site affects, which means we have to balance the 'clean' energy production of the cells with the bad by products of their manufacturing process.
brennantho98

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.
tvedepai00

Devices that Harness Wave Energy | Wave Energy Cost - 2 views

  • Wave energy is an irregular and oscillating low-frequency energy source that can be converted to a 60-Hertz frequency
  • Kinetic energy, the energy of motion, in waves is tremendous. An average 4-foot, 10-second wave striking a coast puts out more than 35,000 horsepower per mile of coast.
  • It varies in intensity, but it is available twenty-four hours a day, 365 days a year.
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  • Because wave energy needs only 1/200 the land area of wind and requires no access roads, infrastructure costs are less;
  • or now, the best wave generator technology in place in the United Kingdom is producing energy at an average projected/assessed cost of 7.5 cents kWh. In comparison, electricity generated by large scale coal burning power plants costs about 2.6 cents per kilowatt-hour.
  • the sun shines, wave energy will never be depleted
  • As long as
  • produce energy at about 4.5 cents kWh.
  • 7.5 cents kWh
  • In comparison, electricity generated by large scale coal burning power plants costs about 2.6 cents per kilowatt-hour.
  • about 3 cents per kilowatt hour
  • Wave energy devices are quieter and much less visually obtrusive than wind devices
leonardsar99

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.
  •  
    the sun
adamsaub98

How long has the concept of tidal power been around? | GreenAnswers - 0 views

  • Mills using tidal power can be dated back to 12th century Europe,
whalenkil98

Institute for Energy Research | Fossil Fuels - 1 views

  • Scattered records of the use of coal date to at least 1100 BC.
dpurdy

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.
dpurdy

How Does CO2 Cause Global Warming? | eHow.com - 0 views

  • Carbon dioxide contributes to global warming by absorbing heat energy from the earth, trapping it and preventing its release into space.
dpurdy

What Is Biodiesel - 0 views

  • The Transesterification process is the reaction of a triglyceride (fat/oil) with an alcohol to form esters and glycerol
dpurdy

Transesterification - Definition, Glossary, Details - Oilgae - 0 views

  • The main reaction for converting oil to biodiesel is called transesterification.
  • The transesterification process reacts an alcohol (like methanol) with the triglyceride oils contained in vegetable oils, animal fats, or recycled greases, forming fatty acid alkyl esters (biodiesel)
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