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kenyonlau99

How much power is generated in the United States by solar power? - 2 views

  • just over 843,000 kilowatt-hours of electricity were provided by solar power. The vast majority of that, more than 666,500 kWh, were produced in California. Roughly 14 percent of the total renewable energy generated in the U.S. in 2008 was solar energy. And remember that these numbers continue to grow each year. The solar industry has been growing on an average of 30-40 percent each year, and as the industry grows, so will the amount of clean, renewable power it puts out. Interested in Home Solar Energy? Fill in your details below and certified solar contractors will give you FREE estimates. What type of Solar Energy services are you interested in? * Please Select Solar Electrical Solar Thermal First Name * Last Name * Zipcode *
    • kenyonlau99
       
      GOOD INFO!
  • The EIA states that just over 843,000 kilowatt-hours of electricity were provided by solar power. The vast majority of that, more than 666,500 kWh, were produced in California. Roughly 14 percent of the total renewable energy generated in the U.S. in 2008 was solar energy. And remember that these numbers continue to grow each year. The solar industry has been growing on an average of 30-40 percent each year, and as the industry grows, so will the amount of clean, renewable power it puts out.
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    how much solar energy is being converted in the USA?
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    "How much power is generated in the United States by solar power? ted-vollgraff According to the Energy Information Administration (EIA), renewable energy accounted for 7 percent of U.S. energy consumption in 2008. Solar power accounted for only one percent. But, considering how much energy is consumed each year in the United States, that is still a decent bit of power. The EIA states that just over 843,000 kilowatt-hours of electricity were provided by solar power. The vast majority of that, more than 666,500 kWh, were produced in California. Roughly 14 percent of the total renewable energy generated in the U.S. in 2008 was solar energy. And remember that these numbers continue to grow each year. The solar industry has been growing on an average of 30-40 percent each year, and as the industry grows, so will the amount of clean, renewable power it puts out. "
ricciardellinick

Energy Studies - How Fuel Cell Works - 2 views

  • Hydrogen is the simplest of all elements with one electron and one proton. Two hydrogen atoms form one hydrogen gas molecule, or H2, but this gas is rarely found in large quantities in nature. Hydrogen’s chemical properties allow it to combine easily with other elements to form other molecules.
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    "Hydrogen is the simplest of all elements with one electron and one proton. Two hydrogen atoms form one hydrogen gas molecule, or H2, but this gas is rarely found in large quantities in nature. Hydrogen's chemical properties allow it to combine easily with other elements to form other molecules"
whalenkil98

Where does solar energy come from - 1 views

  • Solar energy originates in the depths of our sun. The sun endures a continuous stream of thermonuclear explosions as hydrogen atoms are fused into helium atoms. We encounter the resultant energy as radiation that strikes the surface of the earth.
    • kenyonlau99
       
      so once the rays of the sun hit the solar panel it then is turned into energy .Fully powered by the sun.
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    "Solar energy originates in the depths of our sun."
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    Where solar energy is formed and how it is formed.
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    .Fully powered by the sun.
dpurdy

How do Photovoltaics Work? - NASA Science - 1 views

  • Photovoltaics is the direct conversion of light into electricity at the atomic level. Some materials exhibit a property known as the photoelectric effect that causes them to absorb photons of light and release electrons. When these free electrons are captured, an electric current results that can be used as electricity.
  • When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity. This electricity can then be used to power a load, such as a light or a tool.
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    " Solar cells are made of the same kinds of semiconductor materials, such as silicon, used in the microelectronics industry. For solar cells, a thin semiconductor wafer is specially treated to form an electric field, positive on one side and negative on the other. When light energy strikes the solar cell, electrons are knocked loose from the atoms in the semiconductor material. If electrical conductors are attached to the positive and negative sides, forming an electrical circuit, the electrons can be captured in the form of an electric current -- that is, electricity. This electricity can then be used to power a load, such as a light or a too"
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    "The photoelectric effect was first noted by a French physicist, Edmund Bequerel, in 1839, who found that certain materials would produce small amounts of electric current when exposed to light. In 1905, Albert Einstein described the nature of light and the photoelectric effect on which photovoltaic technology is based, for which he later won a Nobel prize in physics. The first photovoltaic module was built by Bell Laboratories in 1954. It was billed as a solar battery and was mostly just a curiosity as it was too expensive to gain widespread use. In the 1960s, the space industry began to make the first serious use of the technology to provide power aboard spacecraft. Through the space programs, the technology advanced, its reliability was established, and the cost began to decline. During the energy crisis in the 1970s, photovoltaic technology gained recognition as a source of power for non-space applications."
dynesbri97

Renewable Solar Energy: How is Wind Formed - 0 views

  • Wind is formed by the indirect effect of the sun on the Earth’s surface. There is a reasonable explanation why is it so. As the sun shines, the Sun heats the Earth's surface; the air near ground level gets hot and rises up. Cold air at higher altitudes replaces it. At nighttime the process is reversed. This is  in principal how is wind formed on Earth.
  • This process of hot air rising and colder air sinking, causes high and low air pressure areas and results in wind formation. The more the pressure changes in an area, the faster the wind speed will be. If two areas are close to each other, pressure difference will cause higher wind speed to be produced compared to areas that are far apart from each other. This is how the wind is formed on Earth and this phenomena is known as vertical wind formation
rutalil00

Wind power - Wikipedia, the free encyclopedia - 1 views

  • Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electricity, windmills for mechanical power, windpumps for water pumping or drainage, or sails to propel ships
  • Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electricity, windmills for mechanical power, windpumps for water pumping or drainage, or sails to propel ships.
  • The total amount of available power from the wind is considerably more than present human power use from all sources.[3] At the end of 2011, worldwide nameplate capacity of wind-powered generators was 238 gigawatts (GW), growing by 41 GW over the preceding year.[4] Wind power now (2010 data) has the capacity to generate 430 TWh annually, which is about 2.5% of worldwide electricity usage.[5][6] Over the past five years (2010 data) the average annual growth in new installations has been 27.6 percent. Wind power market penetration is expected to reach 3.35 percent by 2013 and 8 percent by 2018.[7][8] Several countries have already achieved relatively high levels of wind power penetration, such as 21% of stationary electricity production in Denmark,[5] 18% in Portugal,[5] 16% in Spain,[5] 14% in Ireland[9] and 9% in Germany in 2010.[5][10] As of 2011, 83 countries around the world are using wind power on a commercial basis
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  • A large wind farm may consist of several hundred individual wind turbines which are connected to the electric power transmission network. Offshore wind power can harness the better wind speeds that are available offshore compared to on land, so offshore wind power’s contribution in terms of electricity supplied is higher.[11] Small onshore wind facilities are used to provide electricity to isolated locations and utility companies increasingly buy back surplus electricity produced by small domestic wind turbines. Although a variable source of power, the intermittency of wind seldom creates problems when using wind power to supply up to 20% of total electricity demand, but as the proportion rises, increased costs, a need to use storage such as pumped-storage hydroelectricity, upgrade the grid, or a lowered ability to supplant conventional production may occur.[12][13][14] Power management techniques such as excess capacity, storage, dispatchable backing supply (usually natural gas), exporting and importing power to neighboring areas or reducing demand when wind production is low, can mitigate these problems.
  • Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation, and uses little land. In operation, the overall cost per unit of energy produced is similar to the cost for new coal and natural gas installations.[15] The construction of wind farms is not universally welcomed, but any effects on the environment from wind power are generally much less problematic than those of any other power source
  • Wind is the movement of air across the surface of the Earth, affected by areas of high pressure and of low pressure.[35] The surface of the Earth is heated unevenly by the Sun, depending on factors such as the angle of incidence of the sun's rays at the surface (which differs with latitude and time of day) and whether the land is open or covered with vegetation. Also, large bodies of water, such as the oceans, heat up and cool down slower than the land. The heat energy absorbed at the Earth's surface is transferred to the air directly above it and, as warmer air is less dense than cooler air, it rises above the cool air to form areas of high pressure and thus pressure differentials. The rotation of the Earth drags the atmosphere around with it causing turbulence. These effects combine to cause a constantly varying pattern of winds across the surface of the Earth.[35]
  • Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power, windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships.
  • Compared to the environmental impact of traditional energy sources, the environmental impact of wind power is relatively minor in terms of pollution
  • Wind energy is the kinetic energy of air in motion, also called wind
  • ind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land.[2] The effects on the environment are generally less problematic than those from other powe
  • Wind power is very consistent from year to year but has significant variation over shorter time scales. The intermittency of wind seldom creates problems when used to supply up to 20% of total electricity demand,[5] but as the proportion increases, a need to upgrade the grid, and a lowered ability to supplant conventional production can occur.
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    wind turbine stuff
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    "Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power, windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships."
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    Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land.[2] The effects on the environment are generally less problematic than those from other power sources. As of 2011, Denmark is generating more than a quarter of its electricity from wind and 83 countries around the world are using wind power on a commercial basis.[3] In 2010 wind energy production was over 2.5% of total worldwide electricity usage, and growing rapidly at more than 25% per annum. The monetary cost per unit of energy produced is similar to the cost for new coal and natural gas installations.[4]
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.
kramerjac99

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.
jack wells

The Benefits of Wind Power - Green Living Ideas - 0 views

  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.
  • One of the most important is that wind power is the least expensive of all other forms of alternative energy. 
  • Another tremendous benefit of wind power is that it is a sustainable source of energy and a clean source of energy
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  • Wind energy is also a renewable energy, meaning it does not deplete our natural resources like coal or petroleum based products.
  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free.
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    The benefits of wind energy.
pondalb98

Wind Energy Basics - 5 views

  • 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
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  • 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.
  • remote locations far from areas of electric power demand (such as cities)
  • 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
  • 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.
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    "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."
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    "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."
dpurdy

What is wave energy? | Pelamis Wave Power - 4 views

  • What is wave energy? Waves are generated by the passage of wind across the surface of the sea.  Energy is transferred from the wind to the waves.  Waves travel vast distances across the ocean and at great speed and the energy is concentrated near the water surface.  The energy within a wave is proportional to the square of the wave height.  Therefore a two-meter high wave has four times the power of a one-meter high wave. The longer and stronger the wind blows over the surface of the sea, the higher, longer, faster and more powerful the sea is.
  • Although wave energy is a form of concentrated wind energy, as it has often travelled over large distances it is regularly out of phase with the local wind conditions.  Wave energy can therefore help to balance output variability from other renewable sources and maximise the efficient use of the electricity networks.   Wave energy is also more predictable than many other forms of renewable energy, such as wind or solar, and can be forecast accurately up to five days in advance.
  • Wave energy is clean and renewable!  It is one of the last renewable energy forms which mankind has yet to harness, and its potential is huge.
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  • Wave energy could play a major part in the world’s efforts to combat climate change, potentially displacing 1 – 2 billion tonnes of CO2 per annum from conventional fossil fuel generating sources.
bonnjos98

How long have people been using geothermal energy? - Curiosity - 1 views

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    "It may surprise you to know that the ancient Romans had central heating. They used geothermal energy - in the form of hot springs - to heat their homes. Geothermal heating wasn't used in an organized fashion since until the late 19th century when Boise, Idaho, piped in water from local hot springs to warm buildings. Now, geothermal energy is used globally. Reykjavik, Iceland, leads the world in use of geothermal energy, heating 95 percent of its buildings with heat from below the Earth's surface."
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    "It may surprise you to know that the ancient Romans had central heating. They used geothermal energy - in the form of hot springs - to heat their homes. Geothermal heating wasn't used in an organized fashion since until the late 19th century when Boise, Idaho, piped in water from local hot springs to warm buildings. Now, geothermal energy is used globally. Reykjavik, Iceland, leads the world in use of geothermal energy, heating 95 percent of its buildings with heat from below the Earth's surface."
jack wells

My Library for wind - 0 views

  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free.
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    "One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free."
butlerlex99

Solar Energy Facts: Solar Energy, Solar Cells, Solar Panels | Resourses - 0 views

  • For billions of years, the sun has poured out huge amounts of energy in several forms, including light, heat, radio waves, and even x-ray. The Earth, in orbit around the sun, intercepts a very small part of the sun’s immense output. On Earth, direct sunlight is available from sunrise until sunset, except during solar eclipses. Solar collectors and modules are designed to capture some of the sun’s energy and change it from radiation into more usable forms such as heat or electricity. In fact, sunlight is an excellent source of heat and electricity, the two most important forms of energy we consume.
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    solar energy facts
dpurdy

Explainer: what are biofuels? | Biofuels | SBS World News - 0 views

  • The biofuel industry takes the chemical energy contained in organic materials and converts this into useful energy sources. However, it is not necessarily a sustainable industry. Daniel Tan explains.
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    Explanation of the form of bio fuels.
labrumbra99

A Basic Overview of Fuel Cell Technology - 0 views

  • they generate electricity with very little pollution—much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
  • Scientists and inventors have designed many different types and sizes of fuel cells in the search for greater efficiency, and the technical details of each kind vary
  • in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now “ionized,” and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
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  • But in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now �ionized,� and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
  • Every fuel cell also has an electrolyte, which carries electrically charged particles from one electrode to the other, and a catalyst, which speeds the reactions at the electrodes. Hydrogen is the basic fuel, but fuel cells also require oxygen. One great appeal of fuel cells is that they generate electricity with very little pollution–much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
  • A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes.
  • fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode.
  • One detail of terminology:
  • Oxygen enters the fuel cell at the cathode and, in some cell types (like the one illustrated above), it there combines with electrons returning from the electrical circuit and hydrogen ions that have traveled through the electrolyte from the anode. In other cell types the oxygen picks up electrons and then travels through the electrolyte to the anode, where it combines with hydrogen ions. The electrolyte plays a key role. It must permit only the appropriate ions to pass between the anode and cathode. If free electrons or other substances could travel through the electrolyte, they would disrupt the chemical reaction. Whether they combine at anode or cathode, together hydrogen and oxygen form water, which drains from the cell. As long as a fuel cell is supplied with hydrogen and oxygen, it will generate electricity. Even better, since fuel cells create electricity chemically, rather than by combustion, they are not subject to the thermodynamic laws that limit a conventional power plant (see "Carnot Limit" in the glossary). Therefore, fuel cells are more efficient in extracting energy from a fuel. Waste heat from some cells can also be harnessed, boosting system efficiency still further
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    "A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes."
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    "A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode."
dpurdy

History of Biofuels - BioFuel Information - 1 views

  • Biofuels in the solid form has been in use ever since man discovered fire.
  • Wood was the first form of biofuel that was used even by the ancient people for cooking and heating
  • This form of fuel was discovered even before the discovery of the fossil fuels, but with the exploration of the fossil fuel like gas, coal, and oil the production and use of biofuel suffered a severe impact.
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  • One of the first inventors to convince the people of the use of ethanol was a German named Nikolaus August Otto. Rudolf Diesel is the German inventor of the diesel engine. He designed his diesel engine to run in peanut oil and later Henry Ford designed the Model T car which was produced from 1903 to 1926. This car was completely designed to use hemp derived biofuel as fuel
  • n the period of World War II, the high demand of biofuels was due to the increased use as an alternative for imported fuel. In this period, Germany was one of the countries that underwent a serious shortage of fuel. It was during this period that various other inventions took place like the use of gasoline along with alcohol that was derived from potatoes. Britain was the second country which came up with the concept of grain alcohol mixed with petrol
smithree98

EIA Energy Kids - Hydrogen - 2 views

  • Like electricity, hydrogen is a secondary source of energy. It stores and carries energy produced from other resources (fossil fuels, water, and biomass).
  • ydrogen is the simplest element. Each atom of hydrogen has only one proton. It is also the most plentiful gas in the universe. Stars like the sun are made primarily of hydrogen. The sun is basically a giant ball of hydrogen and helium gases. In the sun's core, hydrogen atoms combine to form helium atoms. This process — called fusion — gives off radiant energy.
  • Hydrogen gas is so much lighter than air that it rises fast and is quickly ejected from the atmosphere. This is why hydrogen as a gas (H2) is not found by itself on Earth. It is found only in compound form with other elements. Hydrogen combined with oxygen, is water (H2O). Hydrogen combined with carbon forms different compounds, including methane (CH4), coal, and petroleum.
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  • Hydrogen has the highest energy content of any common fuel by weight
  • Like electricity, hydrogen is an energy carrier and must be produced from another substance. Hydrogen is not currently widely used, but it has potential as an energy carrier in the future. Hydrogen can be produced from a variety of resources (water, fossil fuels, or biomass) and is a byproduct of other chemical processes.
  • Steam reforming is currently the least expensive method of producing hydrogen and accounts for about 95% of the hydrogen produced in the United States. This method is used in industries to separate hydrogen atoms from carbon atoms in methane (CH4). But the steam reforming process results in greenhouse gas emissions that are linked with global warming.1
  • Electrolysis Creates No Emissions but Is Costly Electrolysis is a process that splits hydrogen from water. It results in no emissions, but it is currently an expensive process. New technologies are currently being developed.
  • Hydrogen fuel cells make electricity. They are very efficient, but expensive to build. Small fuel cells can power electric cars. Large fuel cells can provide electricity in remote places with no power lines.
  • Portable fuel cells are being sold to provide longer power for laptop computers, cell phones, and military applications.
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    tells all about hydrogen
gonzalezisa00

Science of Summer: How Do Ocean Waves Form? | LiveScience - 0 views

  • Presnell explained that wind speed and duration help in determining the size and frequency of ocean waves. Another factor is called "fetch," referring to the span of water over which a breeze blows, and the longer a fetch, the more energy a wave can build up.
olsentri00

Wind Power - 0 views

  • We have been harnessing the wind's energy for hundreds of years. From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain. Today, the windmill's modern equivalent - a wind turbine - can use the wind's energy to generate electricity.
  • Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind. Turbines catch the wind's energy with their propeller-like blades. Usually, two or three blades are mounted on a shaft to form a rotor.
  • A blade acts much like an airplane wing. When the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift. The force of the lift is actually much stronger than the wind's force against the front side of the blade, which is called drag. The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity.
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  • Wind turbines can be used as stand-alone applications, or they can be connected to a utility power grid or even combined with a photovoltaic (solar cell) system. For utility-scale sources of wind energy, a large number of wind turbines are usually built close together to form awind plant. Several electricity providers today use wind plants to supply power to their customers.
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    Today, the windmill's modern equivalent - a wind turbine - can use the wind's energy to generate electricity.
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    Today, the windmill's modern equivalent - a wind turbine - can use the wind's energy to generate electricity.
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