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Biofuels: Journey to Forever - how to make your own clean-burning biofuel - 0 views

journeytoforever.org/biofuel.html biofuel
shared by janosjus99 on 22 Oct 12 - Cached
    • janosjus99
      janosjus99 on 22 Oct 12
       
      history on bio fuels
  • but if everyone had cars like ours, there'd be no need for roads."
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How Is Wave Energy Used to Generate Electricity? | eHow.com - 0 views

www.ehow.com/sed-generate-electricity_.html converted
shared by baileyamb99 on 22 Oct 12 - No Cached
  • Earth is composed mainly of bodies of water---about 71 percent of the earth's surface is water. Ninety-seven percent of that is found in the oceans. Because the earth's surface is curved, the sun heats it unevenly. This causes winds to blow across the water and generate waves. The sun and moon also exert their gravitational pull on the earth, triggering wave-producing tides. Wave motion energy can be harnessed and generated into electricity.
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HowStuffWorks "Algae Biodiesel Engineering: Extracting Oil from Algae " - 0 views

science.howstuffworks.com/...algae-biodiesel2.htm
shared by janosjus99 on 22 Oct 12 - No Cached
  • How can we get oil from algae? It's like getting juice from an orange -- with an additional chemical reaction thrown in
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Biofuels - 0 views

www.voxsolaris.com/biofuels.html cost
shared by pettitmat99 on 22 Oct 12 - No Cached
  • Biofuels are basically any fuel that can be burned in air to produce heat that is produced by biological means, normally by plant growth. Currently the most prominant biofuels are ethanol and bio-deisel because these can be burned in existing internal combustion engines and are thus a direct replacement for oil. The most important biofuel historically is wood with oth
  • Biofuels are currently cheaper than oil although this is only because we are seeing very high oil prices at the moment. Under what might be termed more 'normal' market conditions, biofuels lack any meaningful price advantage. Biofuel production is very labor intensive and very land intensive. Production of ethanol from sugar cane was pioneered by the Brazilians in the 1970's as a solution to an oil import bill they could ill afford. It worked for them as they have plenty of land they can convert to growing sugar cane and at the time, plenty of cheap labor with which to harvest it.
  • he simple truth is the world does not have enough land to produce anywhere near the quantity of biofuels we need to make any dent in our oil consumption. They are only in fashion now oil prices are high and it is cost effective to produce them. Sooner or later food prices will rise to such a point that biofuel production will cease to be economic.
  • ...2 more annotations...
  • In any case the current price of oil is unlikely to be sustained. Much of today's oil prices can be attributed to the geopolitical situation in the Middle East and the hording of oil both for security of supply and more recently as a hedge against the falling dollar.
  • e they cheaper than oil? That depends how you calculate the cost!
  • pettitmat99 on 22 Oct 12
     
    "But herein lies the first problem with biofuels. They may be carbon nuetral but they are certainly not as green as they might be. Not if the land to grow sugar is coming from cutting down the Amazon jungle and not if vast quantities o"
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BBC News - Wilburton giant solar farm connected to National Grid - 0 views

www.bbc.co.uk/...ngland-cambridgeshire-14218355 solar grid transported infrastructure how
shared by dpurdy on 26 Oct 12 - No Cached
  • dpurdy on 26 Oct 12
     
    Video shows farm connected to grid. This shows the type of infrastructure that will need to be installed. 
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How the Air Moves Forming Winds - 0 views

www.technologystudent.com/...wind1.htm
shared by chadwickall99 on 23 Oct 12 - No Cached
  • Wind power is generated by moving air. As the sun heats the land, the air above also warms and rises. Cold air then replaces the rising air. This creates the winds that we feel most days of the year.
  • If you visit the seaside or coastal area you will probably find that the weather is more breezy or windy than inland. This is because the warm air rises over the land and cold air over the sea replaces it.
  • chadwickall99 on 23 Oct 12
     
    "As the sun heats the land, the air above also warms and rises. Cold air then replaces the rising air. This creates the winds that we feel most days of the year. "
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Photoelectric effect - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/...Photoelectric_effect solar how converted
shared by phinneycha99 on 26 Oct 12 - Cached
  • 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
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http://www.nrel.gov/docs/fy06osti/39534.pdf - 0 views

www.nrel.gov/...39534.pdf
shared by smithree98 on 26 Oct 12 - No Cached
    • smithree98
      smithree98 on 26 Oct 12
       
      chart that says how much energy hydrogen produces
    • smithree98
      smithree98 on 26 Oct 12
       
      not just hydyogen
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HowStuffWorks "How Fuel Cells Work" - 1 views

auto.howstuffworks.com/...fuel-cell1.htm hydrogen future potential uses history
shared by dpurdy on 26 Oct 12 - Cached
  • The fuel cell will compete with many other energy­ conversion devices, including the gas turbine in your city's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.
  • Sir William Grove invented the first fuel cell in 1839. Grove knew that water could be split into hydrogen and oxygen by sending an electric current through it (a process called electrolysis). He hypothesized that by reversing the procedure you could produce electricity and water. He created a primitive fuel cell and called it a gas voltaic battery. After experimenting with his new invention, Grove proved his hypothesis. Fifty years later, scientists Ludwig Mond and Charles Langer coined the term fuel cell while attempting to build a practical model to produce electricity.
  • carrowluk99 on 26 Oct 12
     
    " Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently."
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How is Wind Formed? - Answers.Ask.com - 0 views

answers.ask.com/...how_is_wind_formed
shared by dynesbri97 on 13 Mar 12 - No Cached
  • Wind is formed when heats over a large area, causing the air to expand and causing a pressure change. When a low pressure system runs into a high pressure system, it causes a change in the air resulting in wind
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HowStuffWorks "How Solar Cells Work" - 0 views

science.howstuffworks.com/...solar-cell.htm solar
shared by smithcol98 on 13 Mar 12 - Cached
  • ough light, they seem to work forever. Y
  • ong as there's
    • smithcol98
      smithcol98 on 13 Mar 12
       
      hi max
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How does wind form - 0 views

wiki.answers.com/...How_does_wind_form
shared by dynesbri97 on 13 Mar 12 - No Cached
  • All winds are caused by differences in air pressure, which are usually caused by the sun. When high air pressure flow into low air pressure, it creates wind.Our planet turns around the Sun on an axis with a 23 degree tilt towards the North Star. The difference of heating on the surface of the Earth (between the equator and the pole) causes a mass of hot air to go up and to displace colder air toward the bottom - this all causes movement in the mass of air that is contain in our atmosphere.
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http://www.hydrogen.energy.gov/pdfs/doe_h2_fuelcell_factsheet.pdf - 3 views

www.hydrogen.energy.gov/...doe_h2_fuelcell_factsheet.pdf hydrogen potential future how
shared by efana1 on 13 Mar 12 - No Cached
    • efana1
      efana1 on 15 Mar 12
       
      Good overview of the potential uses
  • daleymax98 on 13 Mar 12
     
    Facts about Hydrogen Fuel Cells
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Solar Energy Facts - 0 views

www.jc-solarhomes.com/solar_energy_facts.htm
shared by gillinghammic98 on 15 Mar 12 - Cached
  • he energy from the sun  varies from place to place and is very dependent on weather conditions. Without an atmosphere 1.4 KW/m2 per hour is available, but with an atmosphere we can only count on 1KW/m2 per hour in the absence of clouds. So, if asked how much 3 hours of sunlight on one square meter is worth what would you say?
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TLC Home "How many solar cells would I need in order to provide all of the electricity ... - 0 views

tlc.howstuffworks.com/...question418.htm
shared by gillinghammic98 on 15 Mar 12 - No Cached
  • Because solar electricity is so expensive, you would normally go to great lengths to reduce your electricity consumption. Instead of a desktop computer and a monitor you would use a laptop computer. You would use fluorescent lights instead of incandescent. You would use a small B&W TV instead of a large color set. You would get a small, extremely efficient refrigerator­. By doing these things you might be able to reduce your average power consumption to 100 watts. This would cut the size of your solar panel and its cost by a factor of 6, and this might bring it into the realm of possibility.
  • From our calculations and assumptions abo­ve, we know that a solar panel can generate 70 milliwatts per square inch * 5 hours = 350 milliwatt hours per day. Therefore you need about 41,000 square inches of solar panel for the house. That's a solar panel that measures about 285 square feet (about 26 square meters). That would cost around $16,000 right now. Then, because the sun only shines part of the time, you would need to purchase a battery bank, an inverter, etc., and that often doubles the cost of the installation.If you want to have a small room air conditioner in your bedroom, double everything.
  • A "typical home" in America can use either electricity or gas to provide heat -- heat for the house, the hot water, the clothes dryer and the stove/oven. If you were to power a house with solar electricity, you would certainly use gas appliances because solar electricity is so expensive. This means that what you would be powering with solar electricity are things like the refrigerator, the lights, the compute­r, the TV, stereo equipment, motors in things like furnace fans and the washer, etc. Let's say that all of those things average out to 600 watts on average. Over the course of 24 hours, you need 600 watts * 24 hours = 14,400 watt-hours per day.
  • ...1 more annotation...
  • The thing to remember, however, is that 100 watts per hour purchased from the power grid would only cost about 24 cents a day right now, or $91 a year. That's why you don't see many solar houses unless they are in very remote locations. When it only costs about $100 a year to purchase power from the grid, it is hard to justify spending thousands of dollars on a solar system.
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Hydrogen Fuel Cells - Disadvantages - 0 views

www.columbia.edu/...h-fuel-cell-disadv.html cells fuel disadvantages what hydrogen cost how potential
shared by crandallchr98 on 15 Mar 12 - No Cached
  • Fuel cells are currently very expensive, but since they have a simple construction, mass production costs would become extremely low. 
  • Prototype fuel cells last only 1/5th as long as would be needed to make fuel cells cost-effective.
  • They are energy losers because it costs more to produce hydrogen than is earned by using hydrogen in fuel cells:  Electricity generated by fuel cells in cars costs thousands of dollars per kilowatt:  This would have to fall by a factor of 10 for fuel cells to become economically viable.
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Wind Energy Basics - 5 views

windeis.anl.gov/...index.cfm wind convert
shared by pondalb98 on 13 Mar 12 - Cached
  • Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity.
  • The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity
  • The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power
  • ...19 more annotations...
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current
  • Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model
  • wind farm, and generate bulk electrical power
  • Utility-scale turbines range in size from 50 to 750 kilowatts. Single small turbines, below 50 kilowatts
  • Wind energy is very abundant in many parts of the United States. Wind resources are characterized by wind-power density classes, ranging from class 1 (the lowest) to class 7 (the highest). Good wind resources (e.g., class 3 and above, which have an average annual wind speed of at least 13 miles per hour) are found in many locations (see United States Wind Energy Resource Map)
  • free, renewable resource, so no matter how much is used today, there will still be the same supply in the future
  • clean, non-polluting, electricity. Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases
  • higher initial investment than fossil-fueled generators. Roughly 80% of the cost is the machinery, with the balance being site preparation and installation.
  • Although wind power plants have relatively little impact on the environment compared to fossil fuel power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and birds and bats having been killed (avian/bat mortality) by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants
  • remote locations far from areas of electric power demand (such as cities)
  • alternative uses may be more highly valued than electricity generation. However, wind turbines can be located on land that is also used for grazing or even farming
  • Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity.
  • The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity to power homes, businesses, schools, and the like.
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
  • Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines.
  • Wind is a form of solar energy
  • The terms "wind energy" or "wind power
  • describe the process by which the wind is used to generate mechanical power or electricity.
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current. Simply stated, a wind turbine is the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity.
  • freeberntay99 on 08 Mar 13
     
    "Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover. This wind flow, or motion energy, when "harvested" by modern wind turbines, can be used to generate electricity."
  • pondalb98 on 12 Mar 13
     
    "Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor. Most large modern wind turbines are horizontal-axis turbines."
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How do wind turbines transform the energy found in the wind - 1 views

wiki.answers.com/...m_the_energy_found_in_the_wind wind energy
shared by big_jerome on 19 Mar 12 - No Cached
  • A wind turbine is a rotating machine which converts the kinetic energy in wind into mechanical energy. If the mechanical energy is used directly by machinery, such as a pump or grinding stones, the machine is usually called a windmill.
  • wind t
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Wind Energy America - FAQs - 1 views

www.windenergyamerica.com/faqs.html wind
shared by bishophan00 on 19 Mar 12 - No Cached
  • Simply put, an average one megawatt wind turbine will produce enough energy for the annual needs of 350 average households. The amount of energy produced by a turbine varies depending on several factors, namely the size and reliability of the turbine, and the speed that the wind is blowing. These factors together produce the turbine’s capacity. Typically modern turbines range in size from 660 kilowatts to over 3 megawatts of capacity. They are placed in fairly windy locations with minimum wind speeds in the range of six meters per second (around 13 miles per hour). Wind turbines generally run at 30 to 40 percent capacity, so a 1 MW turbine could produce around 3 million KWh of electricity in a year.
  • , wind energy could provide 20% of America’s electricity.
  • According to the American Wind Energy Association, the total U.S. production of wind power is around 25 gigawatts
  • freeberntay99 on 08 Mar 13
     
    "Simply put, an average one megawatt wind turbine will produce enough energy for the annual needs of 350 average households. The amount of energy produced by a turbine varies depending on several factors, namely the size and reliability of the turbine, and the speed that the wind is blowing. These factors together produce the turbine's capacity. Typically modern turbines range in size from 660 kilowatts to over 3 megawatts of capacity. They are placed in fairly windy locations with minimum wind speeds in the range of six meters per second (around 13 miles per hour). Wind turbines generally run at 30 to 40 percent capacity, so a 1 MW turbine could produce around 3 million KWh of electricity in a year."
  • ...2 more comments...
  • wellsann99 on 12 Mar 13
     
    today's wind power
  • kurishkri00 on 24 Sep 13
     
    How much wind power is currently being produced in the United States? According to the American Wind Energy Association, the total U.S. production of wind power is around 25 gigawatts. New wind projects made up 42% of the U.S.'s total new power-producing capacity constructed in 2008, adding 8.4GW of new facilities into the grid.
  • kurishkri00 on 26 Sep 13
     
    What is wind power? Wind power is the result of using the wind to generate electricity. In the past windmills were used to grind grain or pump water. Today, a large wind turbine can power all the electricity needs of at least 350 homes.
  • bishophan00 on 27 Sep 13
     
    , wind energy could provide 20% of America's electricity. Today's wind turbines are very different from the windmills of the past. Moder
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Winds, Waves, Tides - Ocean Energy | Environmental News, Articles & Information | Globa... - 2 views

www.ecoworld.com/...-waves-tides-ocean-energy.html cost how what sustainable future
shared by dpurdy on 03 Nov 11 - No Cached
  • Can Already Cost Under $.06 per Kilowatt Hour * Pneumatic devices, such as the oscillating water column (OWC), use wave motion to compress and decompress air, and drive a turbine. * Float-based devices utilise a buoyant float moving with the waves, reacting against a sea bed anchor in order to harness energy. * Spillover devices utilise wave height to replenish a reservoir of seawater, which runs a turbine. * Raft-type devices use the relative motion of adjacent rafts or pontoons to harness wave energy. * Moving-body devices articulate in the water, inducing motion, which may be used to drive a hydraulic motor.
  • Tidal stream devices extract energy from the diurnal flow of tidal currents (caused by the gravitational pull of the moon). Unlike wind and wave power, tidal streams offer entirely predictable output. However, as the lunar cycle is of around 25 hours’ duration, the timing of peak outputs differs by around an hour each day and tidal energy cannot be guaranteed at times of peak demand.
  • However, several large grid-connected demonstration projects are expected to enter the water in the near future. Tidal stream is thus a few years behind wave energy.
  • ...3 more annotations...
  • Marine Current Turbines is about to field test a submerged 300 kW tidal turbine off Devon in the United Kingdom
  • The manufacturers of all these devices expect to deliver energy at a cost of 10-14 US cents per kWh, falling to below 6 US cents as experience grows and technologies mature
  • Power generation using wave energy is at a much earlier stage of development. Wave energy offers more predictable outputs than wind, but in early 2003 there was only around one megawatt of generating capacity installed worldwide, all of it essentially with demonstration prototypes. Proposed projects are likely to take this to about 6 MW over the next few years. The wave industry is characterised by a wide variety of novel devices
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