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rutalil00

Wind power - Wikipedia, the free encyclopedia - 1 views

en.wikipedia.org/Wind_power

power

shared by rutalil00 on 13 Mar 12 - Cached
  • 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.
  • krolnik98 on 13 Mar 12
     
    wind turbine stuff
  • pondalb98 on 11 Mar 13
     
    "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."
  • rutalil00 on 24 Sep 13
     
    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]
labrumbra99

Sierra Club Green Home » Blog Archive Fuel Cells: Environmental Benefits » Si... - 0 views

www.sierraclubgreenhome.com/...fuel-cells-eco-benefits

fuel cell sustainable

shared by labrumbra99 on 12 Mar 13 - No Cached
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
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  • fuel cells
  • metimes produce a by-product of water or heat, though hydrogen fuel cells are considered more difficult to work with because of transportation and storage. More user friendly fuel cells which use natural gas with emissions that are much lower than those produced by conventional engines or energy sources and can reduce your carbon footprint by around 40%. Additionally, there are only negligible levels of NOx, SOx, Volatile organic compounds and particulates, which is a drastic improvement over traditional means of grid power production. Besides the decreased CO2 emissions and high efficiency rates, fuel c
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country!
  • labrumbra99 on 12 Mar 13
     
    " The environmental impact of fuel cells depends on the type of cell and the fuel being used. Fuel cells can run on a variety of sources, from natural gas to hydrogen to ethanol to biogas. Those that run on hydrogen can sometimes produce a by-product of water or heat, though hydrogen fuel cells are considered more difficult to work with because of transportation and storage. More user friendly fuel cells which use natural gas with emissions that are much lower than those produced by conventional engines or energy sources and can reduce your carbon footprint by around 40%. Additionally, there are only negligible levels of NOx, SOx, Volatile organic compounds and particulates, which is a drastic improvement over traditional means of grid power production. Besides the decreased CO2 emissions and high efficiency rates, fuel cells offer plenty of positive environmental impacts that should be considered by investors and consumers as solutions for cleaner energy are being further researched. 1. Fuel Conservation The use of fuel cells can significantly diminish our dependency on foreign oil. Since fuel cells make energy electrochemically and do not burn fuel like conventional combustion systems, they are much more efficient. Admittedly, some fuel cells need fossil fuels to start their functions; most residential systems run partially off of natural gas. If just 20% of the cars in America used fuel cells, we could cut oil imports by 1.5 million barrels per day. This is $44 billion per year that could remain in the country! 2. Combined Heat and Power The greatest benefit from high powered, well designed fuel cells is the heat and power produced. This means that a property can reduce additional investments to heat their indoor areas or water. In this case, less is more. Since the heat can be redirected to heat water, the environmental benefit from this is the ability to heat the hot water supply without a need for a separate system as is the case with home solar."
pondalb98

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
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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.
  • 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."
tushabeper99

What are the advantages and disadvantages of solar energy - 0 views

wiki.answers.com/..._disadvantages_of_solar_energy

solar advantages disadvantages

shared by tushabeper99 on 11 Mar 13 - No Cached
  • tushabeper99 on 11 Mar 13
     
    "Advantages: Solar power gives you a return on your investment, while paying your utility for electricity gives you 0% return. Solar energy is renewable unlike the conventional resources (coal, oil) which will inevitably run out. Non-polluting, no carbon dioxide like fossil fuels Free except for capital expenses. Longevity - solar panels can last over twenty years Low maintenance - solar panels require very little upkeep Independence - an off-grid system allows you to break free from the electrical grid Environmentally friendly because the conversion of energy doesn't produce any carbon dioxide. It comes from the sun, which, unless you are in The South or North pole, comes out almost everyday Solar power is better for the environment, compared to burning fossil fuels and other electrical power. sun is renewable You get clean energy without harming the environment [in term of carbon emissions] , in certain countries, excessive power generated can be sold back to local electricity provider reduces pollution helps create jobs - shores up economy - to build -> you hire - innovate-maintain - basically economic activities reduced dependence on fossil fuels Once installed, the power is free It is environmentally friendly and no pollution is associated with solar power You can sell your excess power back to the power companies It can be installed anywhere You can use batteries to store power for use at night Energy from the sun is renewable, that is, it keeps on coming It is free It does no damage to the earth or its atmosphere It produces no carbon dioxide It doesn't have to be dug up from the ground like coal, oil, natural gas, or uranium It doesn't have to be cut down, like wood from forests. It produces clean, green power in the form of electricity and can be used to power just about everything we need. There is more solar energy landing on the earth every day than it would take to supply the world for a year. Solar energy can heat swimming pools, power calcul
stockmanchl99

History of BioFuel | www.stillisstillmoving.com - 0 views

stillisstillmoving.com/...history-of-biofuel

biofuel

shared by stockmanchl99 on 22 Oct 12 - No Cached
  • Fueling up with ethanol and vegetable oils  was common long before the development of the internal combustion engine. Vegetable and animal oil lamps have been used since the dawn of civilization. Increasingly efficient heaters and lamps meant that higher quality fuels were developed.  For example, small alcohol stoves (also called “spirit lamps”) were commonly used by travelers in the 17th century to warm food and themselves. One of Ben Franklin’s spirit lamps is on display in a Philadelphia exhibit.
  • Fueling up with ethanol and vegetable oils  was common long before the development of the internal combustion engine. Vegetable and animal oil lamps have been used since the dawn of civilization. Increasingly efficient heaters and lamps meant that higher quality fuels were developed.  For example, small alcohol stoves (also called “spirit lamps”) were commonly used by travelers in the 17th century to warm food and themselves. One of Ben Franklin’s spirit lamps is on display in a Philadelphia exhibit.
  • At the end of WWI, gasoline quality was declining, and Detroit dropped the standard compression ratio to 3.8 to one. According to Scientific American in 1919, there were to options. One, lower the compression ratio even further, sacrificing efficiency but allowing the continued use of low-grade petroleum.  Or two, use more ethanol in the fuel mix in order to conserve petroleum and allow the creation of more efficient, higher compression engines.  The choice was further skewed in the direction of ethanol when the US Geological Survey announced, in 1920, that oil was running out.[20]
  • stockmanchl99 on 08 Mar 13
     
    "Around the 1850s, lamp fuels in the US and Europe were usually made from animal and vegetable oils, often combined with alcohol.  "Camphene" (a camphor oil scented blend of turpentine and ethanol) was by far the leading fuel in the US with at least 90 million gallons sold per year.[14] But a tax on all alcohol in the US, including industrial alcohol for lamps, meant that other sources of illuminants were needed.  The kerosene industry arose as a direct result of this tax on its competitor - and not because whales were running out, as the "whale oil" myth would have it. "Kerosene" was named as the solar (keros) fuel in imitation of  "camphene." The highly volatile byproduct, called "gasoline" in the hope it would be used in municipal gas light systems, was usually blended unsafely into lamp fuels, or just poured into streams or burned off."
bonnjos98

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

curiosity.discovery.com/...-long-people-geothermal-energy

geothermal history

shared by bonnjos98 on 12 Mar 13 - No Cached
  • knightoli99 on 12 Mar 13
     
    "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."
  • bonnjos98 on 13 Mar 13
     
    "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."
knightoli99

Geothermal Electricity Production - Geothermal Energy - Renewable Energy World - 0 views

www.renewableenergyworld.com/...geoelectricity

geothermal convert

shared by knightoli99 on 12 Mar 13 - No Cached
  • knightoli99 on 12 Mar 13
     
    " Geothermal Electricity Production Most power plants need steam to generate electricity. The steam rotates a turbine that activates a generator, which produces electricity. Many power plants still use fossil fuels to boil water for steam. Geothermal power plants, however, use steam produced from reservoirs of hot water found a couple of miles or more below the Earth's surface. There are three types of geothermal power plants: dry steam, flash steam, and binary cycle. Dry steam power plants draw from underground resources of steam. The steam is piped directly from underground wells to the power plant, where it is directed into a turbine/generator unit. There are only two known underground resources of steam in the United States: The Geysers in northern California and Yellowstone National Park in Wyoming, where there's a well-known geyser called Old Faithful. Since Yellowstone is protected from development, the only dry steam plants in the country are at The Geysers. This geothermal power plant generates electricity for the Imperial Valley in California. Credit: Warren Gretz Flash steam power plants are the most common. They use geothermal reservoirs of water with temperatures greater than 360°F (182°C). This very hot water flows up through wells in the ground under its own pressure. As it flows upward, the pressure decreases and some of the hot water boils into steam. The steam is then separated from the water and used to power a turbine/generator. Any leftover water and condensed steam are injected back into the reservoir, making this a sustainable resource. Binary cycle power plants operate on water at lower temperatures of about 225°-360°F (107°-182°C). These plants use the heat from the hot water to boil a working fluid, usually an organic compound with a low boiling point. The working fluid is vaporized in a heat exchanger and used to turn a turbine. The water is then injected back into the ground to be reheated. The water and the working fluid are
butlerlex99

Quick Facts about Solar Energy | Solarbuzz - 0 views

www.solarbuzz.com/...quick-facts

solar solar power facts

shared by butlerlex99 on 12 Mar 13 - No Cached
  • Quick and interesting facts related to solar energy.  For more terms and explanations, consult our solar glossary. One kilowatt equals 1,000 watts. One kilowatt-hour (kWh) equals the amount of electricity needed to burn a 100 watt light bulb for 10 hours. A sunny location (like Los Angeles, California, US) receives an average of 5.5 hours of sunlight per day each year. A cloudy location (like Hamburg, Germany) receives 2.5 hours per day of sunlight each year. A 1 kilowatt peak solar system generates around 1,600 kilowatt hours per year in a sunny climate and about 750 kilowatt hours per year in a cloudy climate. A solar energy system can provide electricity 24 hours a day when the solar electric modules are combined with batteries in one integrated energy system. Solar modules produce electricity even on cloudy days, usually around 10-20% of the amount produced on sunny days. The typical components of a solar home system include the solar module, an inverter, a battery, a charge controller (sometimes known as a regulator), wiring, and support structure. A typical silicon cell solar module will have a life in excess of 20 years Monthly average residential consumption of electricity in the US in 2008 was 920 kilowatt hours. (Source: US DOE) Monthly average residential electricity bill in the US in 2008 was $103.67. (Source: US DOE)  
  • One kilowatt equals 1,000 watts. One kilowatt-hour (kWh) equals the amount of electricity needed to burn a 100 watt light bulb for 10 hours. A sunny location (like Los Angeles, California, US) receives an average of 5.5 hours of sunlight per day each year. A cloudy location (like Hamburg, Germany) receives 2.5 hours per day of sunlight each year. A 1 kilowatt peak solar system generates around 1,600 kilowatt hours per year in a sunny climate and about 750 kilowatt hours per year in a cloudy climate. A solar energy system can provide electricity 24 hours a day when the solar electric modules are combined with batteries in one integrated energy system. Solar modules produce electricity even on cloudy days, usually around 10-20% of the amount produced on sunny days. The typical components of a solar home system include the solar module, an inverter, a battery, a charge controller (sometimes known as a regulator), wiring, and support structure. A typical silicon cell solar module will have a life in excess of 20 years Monthly average residential consumption of electricity in the US in 2008 was 920 kilowatt hours. (Source: US DOE) Monthly average residential electricity bill in the US in 2008 was $103.67. (Source: US DOE)
  • butlerlex99 on 12 Mar 13
     
    ddid you knows about solar energy
behanjos99

What are geothermal energy advantages and disadvantages? - 0 views

cognitiveanomalies.com/y-advantages-and-disadvantages

disadvantages geothermal form

shared by behanjos99 on 11 Mar 13 - No Cached
  • Advantages: Geothermal energy cost is extremely low compared to many other energy sources. It has low pollution compared to fossil fuels and nuclear energy. Geothermal energy is a renewable energy source. Almost no environmental impact when using geothermal heat from nuclear decay. Geothermal heat pump systems can reduce your energy use storing heat from the summer/sun and makes use of it in the night and winter. Low maintenance systems.
  • Disadvantages: The most important disadvantage is absolutely the geological problem.  The heat source is mostly close to volcanic activity of some sort. Chemicals are byproducts of the production electricity with hot ground water. Some geothermal plants use a lot of water and it needs to go somewhere its after use. Some of the poluting chemicals in that water and steam are sulfur, mercury, hydrogen sulfide, arsenic, ammonia. Earth is a changing creature.  A drilled hole in the ground could supply thousands of homes heat and one earthquake could change that in a second.  It can also change gradually over time. Location, location, location.  That is certainly true of geothermal energy.  It cannot be transported over vast distances.  If used to heat up houses or for hot tap water it is only the quality of the pipe that delivers the water that determines how far it can go and if it will be of any use when it arrives. If the heat is used for electrical production it helps to have plants close so the energy loss is not too great. 
  • Corrosion is a big problem.  Composition of the chemicals can vary but it is always a problem.  It is among other the reason they need to heat up clean water to use and do not use it directly in to heating of houses.  In cases it has been used directly it causes pipes to corrode. In nuclear heating rock the rock cools down over few decades and hundreds of years are needed to get initial heating back.  Power stations of that sort are therefore not considered as profitable. Geothermal Heat pump systems do have high installation cost. Some areas run out of water or run low on ground water during seasonal dry spells. Less water means less heat and less energy to produce. Some drilling sites are too hot to handle.  Yea. Drillers have actually tried and tried some holes and they just can’t get the needed equipment in because the holes shoot it out like guns.   With workers running to stay alive while steel rains down on them. 
tillmanash98

Biofuel potential is bleak - 3 views

ff.org/...biofuel.htm

biofuels potential

shared by tillmanash98 on 15 Mar 12 - No Cached
  • 12.48 billion gal of ethanol
  • The 2004 US corn crop totaled about 11.7 billion bushels,
  • The entire 2004 US corn and soybean crop, converted to biomass fuels, could replace about 10.41 billion gal of petroleum (7.6 billion as ethanol and 2.81 billion as biodiesel).
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  • The US consumed about 7.49 billion bbl of petroleum last year,
  • This means that the total biofuel potential of the record 2004 US corn and soybean harvests would offset about 12 days of US petroleum consumption, or about 3.3% of our total yearly petroleum consumption
  • Given that most of the US corn and soybean crop is already committed to other uses, this analysis indicates that biomass-based fuels will have a negligible role in reducing US petroleum consumption, which in turn underscores that replacing petroleum in the US economy will be a monumental challenge.
  • tillmanash98 on 15 Mar 12
     
    The 2004 US corn crop totaled about 11.7 billion bushels, the largest ever
filionmar99

EIA Energy Kids - Biofuels - 0 views

www.eia.gov/...energy.cfm

biofuel energy

shared by filionmar99 on 03 Nov 11 - No Cached
  • "Biofuels" are transportation fuels like ethanol and biodiesel that are made from biomass materials.
  • Ethanol and biodiesel are usually more expensive than the fossil fuels that they replace, but they are also cleaner-burning fuels, producing fewer air pollutants.
  • What Is Ethanol? Ethanol is an alcohol fuel made from the sugars found in grains, such as:
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  • Most of the ethanol used in the United States today is distilled from corn
  • As a transportation fuel, ethanol can be used as a total or partial replacement for gasoline
  • Unlike gasoline, pure ethanol is nontoxic and biodegradable; it quickly breaks down into harmless substances if spilled.
  • Ethanol and ethanol-gasoline mixtures burn cleaner and have higher octane than pure gasoline, but have higher "evaporative emissions" from fuel tanks and dispensing equipment. These evaporative emissions contribute to the formation of harmful, ground-level ozone and smog.
  • Ethanol may be considered to be carbon-neutral because the plants that are used to make fuel ethanol (such as corn and sugarcane) absorb CO2 as they grow and may offset the CO2 produced when ethanol is made and burned.
  • However, in some parts of the world, large areas of natural vegetation and forests have been cleared and burned to grow soybeans and palm oil trees to make biodiesel
  • Fueling engines with biodiesel has just started to catch on, but it isn't a new idea. Before petroleum diesel fuel became popular, Rudolf Diesel, the inventor of the diesel engine in 1897, experimented with using vegetable oil (biodiesel) as fuel.
  • Biodiesel as a Transportation Fuel A Bus Powered by Soybean Oil Source: Stock photography (copyrighted) Most trucks, buses, and tractors in the United States use diesel fuel.
  • Using a gallon of biodiesel produced in the United States avoids the CO2 emissions that result from burning about a gallon of petroleum diesel. Biodiesel may be considered to be carbon-neutral because the plants that are used to make it, such as soy beans and palm oil trees, absorb carbon dioxide (CO2) as they grow and may offset the CO2 produced when biodiesel is made and burned.
  • Biodiesel is a renewable fuel that can be used instead of diesel fuel, which is made from petroleum. Biodiesel can be made from vegetable oils, animal fats, or greases. Most biodiesel today is made from soybean oil. About half of biodiesel producers are able to make biodiesel from used oils or fats, including recycled restaurant grease.
  • early all gasoline so
  • Nearly all gasoline sold now in the U.S. contains some ethanol.
  • About 99% of the fuel ethanol consumed in the U.S. is added to gasoline in mixtures of up to 10% ethanol and 90% gasoline.
  • he U.S. Environmental Protection Agency ruled in October 2010, that cars and light trucks of model year 2007 and newer can use E15
dpurdy

EIA Energy Kids - Wind - 1 views

www.eia.gov/...energy.cfm

Wind what history pollution

shared by dpurdy on 03 Nov 11 - No Cached
  • Wind is simply air in motion. It is caused by the uneven heating of the Earth's surface by the sun. Because the Earth's surface is made of very different types of land and water, it absorbs the sun's heat at different rates. One example of this uneven heating can be found in the daily wind cycle.
  • The Daily Wind Cycle During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating wind. At night, the winds are reversed because the air cools more rapidly over land than over water. In the same way, the atmospheric winds that circle the earth are created because the land near the Earth's equator is heated more by the sun than the land near the North and South Poles. Wind Energy for Electricity Generation Today, wind energy is mainly used to generate electricity. Wind is a renewable energy source because the wind will blow as long as the sun shines
  • Like old fashioned windmills, today’s wind machines (also called wind turbines) use blades to collect the wind’s kinetic energy. The wind flows over the blades creating lift, like the effect on airplane wings, which causes them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity. With the new wind machines, there is still the problem of what to do when the wind isn't blowing. At those times, other types of power plants must be used to make electricity.
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  • Wind Production In 2010, wind turbines in the United States generated about 2% of total U.S. electricity generation. Although this is a small fraction of the Nation's total electricity production, it was equal to the annual electricity use of about 8.7 million households.
  • Operating a wind power plant is not as simple as just building a windmill in a windy place. Wind plant owners must carefully plan where to locate their machines. It is important to consider how fast and how much the wind blows at the site
  • As a rule, wind speed increases with altitude and over open areas that have no windbreaks. Good sites for wind plants are the tops of smooth, rounded hills, open plains or shorelines, and mountain gaps that produce wind funneling.
  • Conditions are well suited along much of the coasts of the United States to use wind energy. However, there are people who oppose putting turbines just offshore, near the coastlines, because they think the wind turbines will spoil the view of the ocean. There is a plan to build an offshore wind plant off the coast of Cape Cod, Massachusetts.
  • Wind is a renewable energy source that does not pollute, so some people see it as a good alternative to fossil fuels.
  • Since early recorded history, people have been harnessing the energy of the wind. Wind energy propelled boats along the Nile River as early as 5000 B.C.
  • As late as the 1920s, Americans used small windmills to generate electricity in rural areas without electric service. When power lines began to transport electricity to rural areas in the 1930s, local windmills were used less and less,
  • In the early 1980s, wind energy really took off in California, partly because of State policies that encouraged renewable energy sources.
  • Wind is a clean source of energy, and overall, the use of wind for energy has fewer environmental impacts than using many other energy sources. Wind turbines (often called windmills) do not release emissions that pollute the air or water (with rare exceptions), and they do not require water for cooling. They may also reduce the amount of electricity generated from fossil fuels and therefore reduce the amount of air pollution, carbon dioxide emissions, and water use of fossil fuel power plants.
  • Modern wind turbines are very large machines, and some people do not like their visual impact on the landscape.
  • Some people do not like the sound that wind turbine blades make. Some types of wind turbines and wind projects cause bird and bat deaths. These deaths may contribute to declines in species that are also being affected by other human-related impacts.
  • Most wind power projects on land also require service roads that add to their physical impact on the environment.
  • anonymous on 02 Oct 13
     
    Most quality online stores. Know whether you are a trusted online retailer in the world. Whatever we can buy very good quality. and do not hesitate. Everything is very high quality. Including clothes, accessories, bags, cups. Highly recommended. This is one of the trusted online store in the world. View now www.retrostyler.com
conboyeri98

Fuel cell - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/Fuel_cell

fuelcell fuel cell

shared by conboyeri98 on 21 Mar 12 - Cached
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied.
  • ...8 more annotations...
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent
  • There are many types of fuel cells, but they all consist of an anode (negative side), a cathode (positive side) and an electrolyte that allows charges to move between the two sides of the fuel cell.
  • The principle of the fuel cell was discovered by German scientist Christian Friedrich Schönbein in 1838
  • Stationary fuel cells are used for commercial, industrial and residential primary and backup power generation. Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, communications centers, rural locations including research stations, and in certain military applications. A fuel cell system running on hydrogen can be compact and lightweight, and have no major moving parts. Because fuel cells have no moving parts and do not involve combustion, in ideal conditions they can achieve up to 99.9999% reliability.[49] This equates to less than one minute of downtime in a six-year period.
  • Although there are currently no Fuel cell vehicles available for commercial sale, over 20 FCEVs prototypes and demonstration cars have been released since 2009. Demonstration models include the Honda FCX Clarity, Toyota FCHV-adv, and Mercedes-Benz F-Cell.[64] As of June 2011 demonstration FCEVs had driven more than 4,800,000 km (3,000,000 mi), with more than 27,000 refuelings.[65]
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used.
  • The fuel cell he made used similar materials to today's phosphoric-acid fuel cell.
  • In 2003, U.S. President George W. Bush proposed the Hydrogen Fuel Initiative (HFI). This aimed at further developing hydrogen fuel cells and infrastructure technologies with the goal of producing commercial fuel cell vehicles. By 2008, the U.S. had contributed 1 billion dollars to this project
  • collignonaut99 on 08 Mar 13
     
    "A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied."
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  • conboyeri98 on 11 Mar 13
     
    Explains what a fuel cell is.
  • olearydev99 on 11 Mar 13
     
    "Individual fuel cells produce relatively small electrical potentials, about 0.7 volts, so cells are "stacked", or placed in series, to increase the voltage and meet an application's requirements.[2] In addition to electricity, fuel cells produce water, heat and, depending on the fuel source, very small amounts of nitrogen dioxide and other emissions. The energy efficiency of a fuel cell is generally between 40-60%, or up to 85% efficient if waste heat is captured for use."
  • ricciardellinick on 11 Mar 13
     
    "A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used."
tavarreskat99

Tidal Energy | Pros for Wave and Tidal Power - 3 views

www.oceanenergycouncil.com/...Tidal-Energy.html

pollution tide

shared by tavarreskat99 on 03 Nov 11 - Cached
  • 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.
  • 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.
  • 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.
  • 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.
  • butlerlei98 on 08 Mar 13
     
    "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."
  • kramerjac99 on 11 Mar 13
     
    when it started to be used and who it was used by.
rascoekat00

Tidal power - Wikipedia, the free encyclopedia - 1 views

en.wikipedia.org/...Tidal_power

tidal power history

shared by rascoekat00 on 03 Nov 11 - No Cached
  • The first tidal power station was the Rance tidal power plant built over a period of 6 years from 1960 to 1966 at La Rance, France.[8] It has 240 MW installed capacity.
  • Historically, tide mills have been used, both in Europe and on the Atlantic coast of North America. The incoming water was contained in large storage ponds, and as the tide went out, it turned waterwheels that used the mechanical power it produced to mill grain. [1] The earliest occurrences date from the Middle Ages, or even from Roman times.[2][3] It was only in the 19th century that the process of using falling water and spinning turbines to create electricity was introduced in the U.S. and Europe.[
  • Tides are more predictable than wind energy and solar power.
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  • relatively high cost and limited availability of sites with sufficiently high tidal ranges or flow velocities, thus constricting its total availability. However, many recent technological developments and improvements, both in design (e.g. dynamic tidal power, tidal lagoons) and turbine technology (e.g. new axial turbines, cross flow turbines), indicate that the total availability of tidal power may be much higher than previously assumed
  • Tidal stream generator Main article: Tidal stream generator Tidal stream generators (or TSGs) make use of the kinetic energy of moving water to power turbines, in a similar way to wind turbines that use wind to power turbines. Some tidal generators can be built into the structures of existing bridges, involving virtually no aesthetic problems. Likewise, “tidal bridging” is a relatively new advancement that is gaining recognition as a more practical and beneficial way to generate tidal power. Blue Energy Canada is a company that is focused on building bridges to match today's demands. [9]
  • The first study of large scale tidal power plants was by the US Federal Power Commission in 1924 which if built would have been located in the northern border area of the US state of Maine and the south eastern border area of the Canadian province of New Brunswick, with various dams, powerhouses and ship locks enclosing the Bay of Fundy and Passamaquoddy Bay (note: see map in reference). Nothing came of the study and it is unknown whether Canada had been approached about the study by the US Federal Power Commission.[10] There was also a report on the international commission in April 1961 entitled " Investigation of the International Passamaquoddy Tidal Power Project" produced by both the US and Canadian Federal Governments.
bonnjos98

My Library - 0 views

www.diigo.com/bonnjos98

geothermal

shared by bonnjos98 on 13 Mar 13 - No Cached
  • bonnjos98 on 13 Mar 13
     
    ""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." more from curiosity.discovery.com - Not Cached - Edit - Delete - Share▼ - Preview"
stewartlas97

History of Wind Power - 0 views

www.windturbinesnow.com/history-wind-power.htm

wind

shared by stewartlas97 on 12 Mar 13 - No Cached
  • stewartlas97 on 12 Mar 13
     
    "China has also laid claims to having invented windmills around 2,000 years ago, but the first documented claims appear in the 1200's. Around 250 A.D. the Romans introduced windmills into their culture and in the 700's so did Afghanistan. The Afghanistan windmills were also of the vertical axis style and cloth sails or reed matting was developed to catch the air. These windmills were used to grind corn and sugarcane plus draw water. In the 13th century Holland started developing large horizontal axis windmills. These four-blade windmills were larger, carried more torque and wind speed and could do more work than other windmills previously designed. The Holland windmills were also being used to grind grains and to drain part of the Rhine River. In the 19th century Denmark had an estimated 2,500 windmills and in the U. S. windmills were starting to be used to pump water. The Halladay windmill of 1854 is one such example of this. The first windmill in the world built for electrical production was in 1887 in Scotland built by Professor James Blyth. A year later in 1888 in the U. S. Charles Brush of Cleveland, Ohio built a large wind turbine used to generate electricity."
lefebvrekat99

BIOFUELS: What are they? How can they be used as an energy source (either on-...(Q&A) - 0 views

energyexperts.org/...ResourceDetail.aspx

biodiesel biofuels biofuel form

shared by lefebvrekat99 on 12 Mar 13 - No Cached
  • ofuels can be derived from almost any type of "biomass," a broad term that refers to living or recently alive biological material. Because biomass is produced on a short time scale, it is considered a renewable resource. I will describe types of biofuels—ethanol, biodiesel, syngas, bio-hydrogen, biogas, and solid biofuel—and their use. I'll also identify the crops and wastes being used to produce biofuels, and some issues surrounding biofuel production. How are biofuels being used? Biofuels are already used to supply a small fraction of our energy needs, with significant opportunities to expand their use as infrastructure is developed. In addition to ethanol and biodiesel for transportation, biofuels are currently used for power production, heating and cooling of buildings, and the thermal needs of industry. Biomass is today the largest non-hydroelectric renewable source for electricity produced in the U.S. Most of this is produced in pulp and paper mills, which often generate electricity by burning wood chips, bark, or the sludges and "liquors" that are byproducts of the paper-making process. At the same time, they recover waste heat from electricity generation to meet the thermal needs of the mill. This highly efficient combination is referred to as combined heat and power (CHP) or cogeneration. The electricity generated may be used onsite and/or supplied to the local utility for distribution to the public.
faglejoh98

Geothermal Energy Information, Geothermal Power Facts - National Geographic - 0 views

environment.nationalgeographic.com/...geothermal-profile

geothermal sustainable

shared by faglejoh98 on 08 Mar 13 - No Cached
  • Geothermal energy has been used for thousands of years in some countries for cooking and heating. It is simply power derived from the Earth's internal heat.This thermal energy is contained in the rock and fluids beneath Earth's crust. It can be found from shallow ground to several miles below the surface, and even farther down to the extremely hot molten rock called magma.These underground reservoirs of steam and hot water can be tapped to generate electricity or to heat and cool buildings directly.A geothermal heat pump system can take advantage of the constant temperature of the upper ten feet (three meters) of the Earth's surface to heat a home in the winter, while extracting heat from the building and transferring it back to the relatively cooler ground in the summer
  • There are three types of geothermal power plants: dry steam, flash, and binary. Dry steam, the oldest geothermal technology, takes steam out of fractures in the ground and uses it to directly drive a turbine. Flash plants pull deep, high-pressure hot water into cooler, low-pressure water. The steam that results from this process is used to drive the turbine. In binary plants, the hot water is passed by a secondary fluid with a much lower boiling point than water. This causes the secondary fluid to turn to vapor, which then drives a turbine. Most geothermal power plants in the future will be binary plants.
  • It can be extracted without burning a fossil fuel such as coal, gas, or oil. Geothermal fields produce only about one-sixth of the carbon dioxide that a relatively clean natural-gas-fueled power plant produces.
  • ...1 more annotation...
  • wer plants: dry steam, flash, and binary. Dry steam, the oldest geothermal technology, takes steam out of fractures in the ground and uses it to directly drive a turbine. Flash plants
  • behanjos99 on 08 Mar 13
     
    good info.
  • vanierfel98 on 11 Mar 13
     
    Geothermal energy doesn't release much CO2
  • faglejoh98 on 12 Mar 13
     
    "There are three types of geothermal power plants: dry steam, flash, and binary. Dry steam, the oldest geothermal technology, takes steam out of fractures in the ground and uses it to directly drive a turbine. Flash plants pull deep, high-pressure hot water into cooler, low-pressure water. The steam that results from this process is used to drive the turbine. In binary plants, the hot water is passed by a secondary fluid with a much lower boiling point than water. This causes the secondary fluid to turn to vapor, which then drives a turbine. Most geothermal power plants in the future will be binary plants."
rutalil00

How long has wind power been used? - Curiosity - 0 views

curiosity.discovery.com/...how-long-wind-power-use

history

shared by rutalil00 on 08 Mar 13 - No Cached
  • Windmills were first used to grind grain anywhere from 2000 to 4000 years ago in ancient Persia or Babylon;
  • The initial use of wind power was by Egyptians in 3000 B.C. to move their sailboats.
  • freeberntay99 on 08 Mar 13
     
    "The initial use of wind power was by Egyptians in 3000 B.C. to move their sailboats. Windmills were first used to grind grain anywhere from 2000 to 4000 years ago in ancient Persia or Babylon; crusaders brought the windmill idea back to Europe with them in the 11th century A.D. In the 1930s, windmills in rural areas of the U.S. pumped water and generated electricity."
  • justice colvin on 24 Sep 13
     
    In the 1930s, windmills in rural areas of the U.S. pumped water and generated electricity.
  • kurishkri00 on 24 Sep 13
     
    The initial use of wind power was by Egyptians in 3000 B.C. to move their sailboats. Windmills were first used to grind grain anywhere from 2000 to 4000 years ago in ancient Persia or Babylon; crusaders brought the windmill idea back to Europe with them in the 11th century A.D.
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