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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
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
  • ...19 more annotations...
  • Wind turbines, like aircraft propeller blades, turn in the moving air and power an electric generator that supplies an electric current
  • Modern wind turbines fall into two basic groups; the horizontal-axis variety, like the traditional farm windmills used for pumping water, and the vertical-axis design, like the eggbeater-style Darrieus model
  • wind farm, and generate bulk electrical power
  • Utility-scale turbines range in size from 50 to 750 kilowatts. Single small turbines, below 50 kilowatts
  • Wind energy is very abundant in many parts of the United States. Wind resources are characterized by wind-power density classes, ranging from class 1 (the lowest) to class 7 (the highest). Good wind resources (e.g., class 3 and above, which have an average annual wind speed of at least 13 miles per hour) are found in many locations (see United States Wind Energy Resource Map)
  • free, renewable resource, so no matter how much is used today, there will still be the same supply in the future
  • clean, non-polluting, electricity. Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases
  • higher initial investment than fossil-fueled generators. Roughly 80% of the cost is the machinery, with the balance being site preparation and installation.
  • 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.
  • 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."
labrumbra99

A Basic Overview of Fuel Cell Technology - 0 views

americanhistory.si.edu/...basics.htm

fuel cell convert

shared by labrumbra99 on 15 Mar 12 - Cached
  • 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
  • labrumbra99 on 08 Mar 13
     
    "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."
  • ricciardellinick on 11 Mar 13
     
    "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."
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]
bolendev99

Solar electricity PV (photovoltaic) panels explained - benefits, costs, savings, earnin... - 1 views

www.energysavingtrust.org.uk/...Solar-panels-PV

solar sustainable

shared by bolendev99 on 08 Mar 13 - No Cached
  • bolendev99 on 08 Mar 13
     
    "The benefits of solar electricity Cut your electricity bills: sunlight is free, so once you've paid for the initial installation your electricity costs will be reduced. Get paid for the electricity you generate: the government's Feed-In Tariffs pay you for the electricity you generate, even if you use it. Sell electricity back to the grid: if your system is producing more electricity than you need, or when you can't use it, you can sell the surplus back to the grid. Cut your carbon footprint: solar electricity is green, renewables energy and doesn't release any harmful carbon dioxide] or other pollutants. A typical home solar PV system could save over a tonne of carbon dioxide per year - that's more than 30 tonnes over its lifetime. "
dpurdy

How do Photovoltaics Work? - NASA Science - 1 views

science.nasa.gov/...solarcells

solar history convert

shared by dpurdy on 08 Mar 13 - No Cached
  • 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.
  • bolendev99 on 08 Mar 13
     
    " 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"
  • dpurdy on 12 Mar 13
     
    "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."
dpurdy

Solar Electricity and how it works - Photovoltaic Systems and Components, Grid-Connecte... - 0 views

www.solardirect.com/...pvbasics.htm

grid solar transported works how converted

shared by dpurdy on 26 Oct 12 - No Cached
  • A valuable feature of photovoltaic systems is the ability to connect with the existing power grid which allows owners to sell excessive electricity back to the utility with a plan known as (5) Net Metering. At times when you are not using all of the electricity produced by your system, your meter will spin backwards selling the electricity back to the (6) utility power grid at retail rate.
  • (1) Solar Electric or PV modules convert sunlight to electricity. The PV modules generate DC electricity - or direct current - sending it to the inverter. (2) The inverter transforms the DC power into AC electricity for ordinary household needs. (3) Existing electrical panel distributes solar electricity and utility power to (4) loads (appliances). For systems with a battery backup (optional), the inverter also regulates the charge of batteries. The electricity stored in the batteries can be used at night or during blackouts.
    • dpurdy
      dpurdy on 26 Oct 12
       
      Great video showing solar cell (photovoltaic) in action.
  • dpurdy on 26 Oct 12
     
    Solar is not always connected to grid. Sometimes there are batteries, otherwise your system is connected to grid to share excess electricity.
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
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  • 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.
  • 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."
sconzomic99

What is tidal energy - How tidal works? - Tidal energy - 0 views

www.solarpowernotes.com/...tidal-energy.html

tide energy cost sustainable

shared by sconzomic99 on 11 Mar 13 - Cached
  • tidal energy uses tidal strength of water and back and forth movement  in seas, rivers or oceans. Tidal power exploits kinetic energy of water that power water turbines with its movement between the wings which rotate the turbine to produce electricity.
  • For producing significant amount of energy out of tidal water turbines, range of tides should be high and substantial amount of water should be there for pushing water through the turbine.
  • It is significantly important to spot the appropriate place which provide suitable and sustainable conditions to produce tidal energy, there are plenty of places around the globe which provide good conditions for installing water turbines and then produce electricity use tidal power of oceans in the location.
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  • Once tidal power plant is built its’ electricity is free. It does not emit greenhouse gasses, carbon emission gasses which pollute environment. It does not have any dependency of any fossil fuel including furnace oil, gasses, etc; it needs no oil what so ever to produce electricity. Tidal power technology is renewable energy, which uses tidal and waves of same water for producing electricity over and over again. Tidal power technology like all renewable energy is clean energy and does not leave much impact on environment. Tidal power plants does not require much maintenance, therefore it is maintenance cost free. Tidal energy stations have about 80 % efficiency ratio, where as fossil fuel have approximately 30 % for efficiency levels. Tides in oceans are very predictable, its easy to judge when strong tides are going to show up from water consider weather and other conditions. The better tides and wave strengths of the oceans is, improved the efficiency of the station is. Electricity does not fluctuate on large scale using tidal energy as it happens in solar power technology.
  • Electricity can only be produced when tides are high in the sea, once ocean is calm and does not flow certain level of waves, it cannot produce electricity. Therefore electricity can be produced for only 10 hrs a day in presence of tides.
  • Tidal power plants are not cost effective. Millions of dollars are utilized for developing tidal power which could provide electricity in Megawatts.
  • Once tidal power plant is built its’ electricity is free. It does not emit greenhouse gasses, carbon emission gasses which pollute environment. It does not have any dependency of any fossil fuel including furnace oil, gasses, etc; it needs no oil what so ever to produce electricity. Tidal power technology is renewable energy, which uses tidal and waves of same water for producing electricity over and over again. Tidal power technology like all renewable energy is clean energy and does not leave much impact on environment. Tidal power plants does not require much maintenance, therefore it is maintenance cost free. Tidal energy stations have about 80 % efficiency ratio, where as fossil fuel have approximately 30 % for efficiency levels. Tides in oceans are very predictable, its easy to judge when strong tides are going to show up from water consider weather and other conditions. The better tides and wave strengths of the oceans is, improved the efficiency of the station is. Electricity does not fluctuate on large scale using tidal energy as it happens in solar power technology.
  • not appropriate to risk £15 millions worth of money. This is the main reason why this project is yet start
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
stanglebre99

Wind Development - 0 views

www.citizensenergy.com/...wind-development

transported wind

shared by stanglebre99 on 22 Oct 12 - No Cached
  • Negotiating power purchase agreements
  • In some states, where the electricity market has been deregulated, it is possible for the owner of a wind project to sell electricity directly to customers.  However, wind developers usually sell their electricity to electric utilities, which sell the electricity to customers. T his is usually done by negotiating a power purchase agreement, which is a contract requiring a utility to buy the electricity from a wind farm at a certain price over a certain period of time.  In some cases, an alternative arrangement is reached, in which the developer owns a share of the project long enough to mak
  • In some states, where the electricity market has been deregulated, it is possible for the owner of a wind project to sell electricity directly to customers.  However, wind developers usually sell their electricity to electric utilities, which sell the electricity to customers. T his is usually done by negotiating a power purchase agreement, which is a contract requiring a utility to buy the electricity from a wind farm at a certain price over a certain period of time.  In some cases, an alternative arrangement is reached, in which the developer owns a share of the project long enough to make a specified amount of money.  After this point, the ownership in the project “flips,” and the utility ends up owning the project.
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  • a specified amount of mone
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
     
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dpurdy

Converting Coal into Electricity ~ All About Coal ~ American Coal Foundation - 1 views

www.teachcoal.org/...coalconvert.html

Fossil fuels convert electricity coal grid

shared by dpurdy on 03 Nov 11 - Cached
  • The coal powder mixes with hot air, which helps the coal burn more efficiently, and the mixture moves to the furnace. The burning coal heats water in a boiler, creating steam. Steam released from the boiler powers an engine called a turbine, transforming heat energy from burning coal into mechanical energy that spins the turbine engine. The spinning turbine is used to power a generator, a machine that turns mechanical energy into electric energy. This happens when magnets inside a copper coil in the generator spin.
  • Electricity-generating plants send out electricity using a transformer, which increases the voltage of the electricity based on the amount required and the distance it must travel. Voltages are often as high as 500,000 volts at this point.  Electricity flows along transmission lines to substation transformers. These transformers reduce the voltage for use in the local areas to be served.  From the substation transformers, electricity travels along distribution lines, which can be either above or below the ground, to cities and towns. Transformers once again reduce the voltage—this time to about 120 to 140 volts—for safe use inside homes and businesses. The delivery process is instantaneous. By the time you have flipped a switch to turn on a light, electricity has been delivered.
    • dpurdy
      dpurdy on 03 Nov 11
       
      This previous paragraph is about how electricity gets to your home.
  • anonymous on 05 Oct 13
     
    today hindi news,today news talmi,hindi news www.killdo.de.gg
charlesjos00

How Solar Works in 4 Steps « Energy4Home - 0 views

blogs.constellation.com/...how-solar-works-in-4-steps

solar steps convert

shared by charlesjos00 on 27 Sep 13 - No Cached
  • 1) Individual silicon based (most commonly) cells called photovoltaics (PV) make up the modern day solar panel. These PV cell clusters perform the task of converting incoming sunlight directly into electricity. 2) Wires attached to the panels transport the converted electricity to a piece of equipment called an inverter. The job of the inverter is to convert the solar generated Direct Current (DC) electricity into the type of power your home can use, which is called Alternating Current (AC). 3) After the electricity travels through the inverter, the AC electricity is then transported via wire to your breaker panel to meet your home’s electric demands. 4) The process doesn’t end there, though. There are times when your panels will generate more power than you consume and times when you aren’t generating enough electricity (night times and periods of low light). When your panels are not generating enough solar electricity, you will continue to get power from your local utility. However, when you’re generating a surplus of solar electricity, that excess clean energy will be “net metered” to your local utility grid and you may earn a credit on your power bill for that net metered electricity.
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
dpurdy

Directory:Cents Per Kilowatt-Hour - PESWiki - 9 views

peswiki.com/...ectory:Cents_Per_Kilowatt-Hour

solar tide tidal wind geothermal cost fossil fuels

shared by dpurdy on 08 Nov 11 - Cached
  • Method Cents/kW-h Limitations and Externalities WindCurrently supplies approximately 1.4% of the global electricity demand. Wind is considered to be about 30% reliable. 4.0 - 6.0 Cents/kW-h Wind is currently the only cost-effective alternative energy method, but has a number of problems. Wind farms are highly subject to lightning strikes, have high mechanical fatigue failure, are limited in size by hub stress, do not function well, if at all, under conditions of heavy rain, icing conditions or very cold climates, and are noisy and cannot be insulated for sound reduction due to their size and subsequent loss of wind velocity and power. GeothermalCurrently supplies approximately 0.23% of the global electricity demand. Geothermal is considered 90-95% reliable. 4.5 - 30 Cents/kW-h New low temperature conversion of heat to electricity is likely to make geothermal substantially more plausible (more shallow drilling possible) and less expensive. Generally, the bigger the plant, the less the cost and cost also depends upon the depth to be drilled and the temperature at the depth. The higher the temperature, the lower the cost per kwh. Cost may also be affect by where the drilling is to take place as concerns distance from the grid and another factor may be the permeability of the rock. HydroCurrently supplies around 19.9% of the global electricity demand. Hydro is considered to be 60% reliable. 5.1 - 11.3 Cents/kW-h Hydro is currently the only source of renewable energy making substantive contributions to global energy demand. Hydro plants, however, can (obviously) only be built in a limited number of places, and can significantly damage aquatic ecosystems. SolarCurrently supplies approximately 0.8% of the global electricity demand. 15 - 30 Cents/kW-h Solar power has been expensive, but soon is expected to drop to as low as 3.5 cents/kW-h. Once the silicon shortage is remedied through alternative materials, a solar energy revolution is expected.
  • Tide 2 - 5 Cents/kW-h Blue Energy's tidal fence, engineered and ready for implementation, would provide a land bridge (road) while also generating electricity. Environmental impact is low. Tides are highly predictable.
  • Method Cents/kW-h Limitations and Externalities GasCurrently supplies around 15% of the global electricity demand. 3.9 - 4.4 Cents/kW-h Gas-fired plants and generally quicker and less expensive to build than coal or nuclear, but a relatively high percentage of the cost/KWh is derived from the cost of the fuel. Due to the current (and projected future) upwards trend in gas prices, there is uncertainty around the cost / KWh over the lifetime of plants. Gas burns more cleanly than coal, but the gas itself (largely methane) is a potent greenhouse gas. Some energy conversions to calculate your cost of natural gas per kwh. 100 cubic feet (CCF)~ 1 Therm = 100,000 btu ~ 29.3 kwh. CoalCurrently supplies around 38% of the global electricity demand. 4.8 - 5.5 Cents/kW-h Increasingly difficult to build new coal plants in the developed world, due to environmental requirements governing the plants. Growing concern about coal fired plants in the developing world (China, for instance, imposes less environmental overhead, and has large supplies of high sulphur content coal). The supply of coal is plentiful, but the coal generation method is perceived to make a larger contribution to air pollution than the rest of the methods combined.
behanjos99

Geothermal pollution: Does geothermal energy cause pollution? - 1 views

www.green-energy-efficient-homes.com/geothermal-pollution.html

form geothermal co2

shared by behanjos99 on 12 Mar 13 - No Cached
  • Geothermal electricity generation does involve a small amount of geothermal pollution in that the steam coming up from below ground carries some toxic gases, but in most plants these gases, as well as the steam, are condensed and reinjected into the ground so the effect on the environment is negligible. There are no CO2 emissions from geothermal energy so it is a much better source of electricity than coal or natural gas or nuclear (or even large-scale hydro generation which requires the flooding of large areas of land).
  • Geothermal electricity generation does involve a small amount of geothermal pollution in that the steam coming up from below ground carries some toxic gases, but in most plants these gases, as well as the steam, are condensed and reinjected into the ground so the effect on the environment is negligible. There are no CO2 emissions from geothermal energy so it is a much better source of electricity than coal or natural gas or nuclear (or even large-scale hydro generation which requires the flooding of large areas of land).
  • Geothermal electricity generation does involve a small amount of geothermal pollution in that the steam coming up from below ground carries some toxic gases, but in most plants these gases, as well as the steam, are condensed and reinjected into the ground so the effect on the environment is negligible. There are no CO2 emissions from geothermal energy so it is a much better source of electricity than coal or natural gas or nuclear (or even large-scale hydro generation which requires
  • ...1 more annotation...
  • Geothermal electricity generation does involve a small amount of geothermal pollution in that the steam coming up from below ground carries some toxic gases, but in most plants these gases, as well as the steam, are condensed and reinjected into the ground so the effect on the environment is negligible. There are no CO2 emissions from geothermal energy so it is a much better source of electricity than coal or natural gas or nuclear (or even large-scale hydro generation which requires the flooding of large areas of land).
marloweth98

Solar panel - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/Solar_panel

solar

shared by marloweth98 on 15 Mar 12 - Cached
  • so solar module, photovoltaic module or photovoltaic panel
  • photovoltaic cells
  • arger photovoltaic system to generate and supply electricity in commercial and residential applications. Because a single solar panel can produce only a limited amount of power, many installations contain several panels.
  • ...5 more annotations...
  • Third generation solar cells are advanced thin-film cells. They produce high-efficiency conversion at low cost.
  • photovoltaic system typically
  • includes an array of solar panels, an inverter, and sometimes a battery and interconnection wiring.
  • lexible thin film cells and modules are created on the same production line by depositing the photoactive layer and other necessary layers on a flexible substrate. If the substrate is an insulator (e.g. polyester or polyimide film) then monolithic integration can be used. If it is a conductor then another technique for electrical connection must be used. The cells are assembled into modules by laminating them to a transparent colourless fluoropolymer on the front side (typically ETFE or FEP) and a polymer suitable for bonding to the final substrate on the other side. The only commercially available (in MW quantities) flexible module uses amorphous silicon triple junction (from Unisolar). So-called inverted metamorphic (IMM) multijunction solar cells made on compound-semiconductor technology are just becoming commercialized in July 2008. The University of Michigan's solar car that won the North American Solar Challenge in July 2008 used IMM thin-film flexible solar cells. The requirements for residential and commercial are different in that the residential needs are simple and can be packaged so that as solar cell technology progresses, the other base line equipment such as the battery, inverter and voltage sensing transfer switch still need to be compacted and unitized for residential use. Commercial use, depending on the size of the service will be limited in the photovoltaic cell arena, and more complex parabolic reflectors and solar concentrators are becoming the dominant technology. The global flexible and thin-film photovoltaic (PV) market, despite caution in the overall PV industry, is expected to experience a CAGR of over 35% to 2019, surpassing 32 GW according to a major new study by IntertechPira.[4]
  • t $4.50, which was 33 times lower than the cost in 1970 of $150.[8][9]
  • marloweth98 on 15 Mar 12
     
    facts
gillinghammic98

TLC Home "How many solar cells would I need in order to provide all of the electricity ... - 0 views

tlc.howstuffworks.com/...question418.htm

shared by gillinghammic98 on 15 Mar 12 - No Cached
  • Because solar electricity is so expensive, you would normally go to great lengths to reduce your electricity consumption. Instead of a desktop computer and a monitor you would use a laptop computer. You would use fluorescent lights instead of incandescent. You would use a small B&W TV instead of a large color set. You would get a small, extremely efficient refrigerator­. By doing these things you might be able to reduce your average power consumption to 100 watts. This would cut the size of your solar panel and its cost by a factor of 6, and this might bring it into the realm of possibility.
  • From our calculations and assumptions abo­ve, we know that a solar panel can generate 70 milliwatts per square inch * 5 hours = 350 milliwatt hours per day. Therefore you need about 41,000 square inches of solar panel for the house. That's a solar panel that measures about 285 square feet (about 26 square meters). That would cost around $16,000 right now. Then, because the sun only shines part of the time, you would need to purchase a battery bank, an inverter, etc., and that often doubles the cost of the installation.If you want to have a small room air conditioner in your bedroom, double everything.
  • A "typical home" in America can use either electricity or gas to provide heat -- heat for the house, the hot water, the clothes dryer and the stove/oven. If you were to power a house with solar electricity, you would certainly use gas appliances because solar electricity is so expensive. This means that what you would be powering with solar electricity are things like the refrigerator, the lights, the compute­r, the TV, stereo equipment, motors in things like furnace fans and the washer, etc. Let's say that all of those things average out to 600 watts on average. Over the course of 24 hours, you need 600 watts * 24 hours = 14,400 watt-hours per day.
  • ...1 more annotation...
  • The thing to remember, however, is that 100 watts per hour purchased from the power grid would only cost about 24 cents a day right now, or $91 a year. That's why you don't see many solar houses unless they are in very remote locations. When it only costs about $100 a year to purchase power from the grid, it is hard to justify spending thousands of dollars on a solar system.
chakrabortyshi00

Tidal Power: Nature's renewable hydro electric engine: Additional info - 2 views

www.bionomicfuel.com/wer-new-source-of-hydro-energy

sustainable wave

shared by chakrabortyshi00 on 12 Mar 13 - No Cached
  • Tidal power energy is still being studied and developed, but in the future it could be a major renewable hydropower energy source.
  • England, for example, could supply over 10 percent of its electricity in this way.
  • . Wind and solar energy generators convert much less.
  • ...2 more annotations...
  • They can convert about 80 percent of the energy into electricity
  • Another disadvantage is that the start-up costs involved are very high and a lot of time is required for the construction projects, which can cost millions of dollars and take up to 10 years to build
  • chakrabortyshi00 on 26 Sep 13
     
    Tidal hydropower energy has various advantages. The first of these is reliability and consistency. Other alternative energy sources like wind and solar can have varying amounts of energy generated depending on the weather conditions. Tidal power energy can generate electricity by the clock and indefinitely. This means that shortages can be easily avoided. In addition, tidal turbines are efficient when it comes to generating energy. They can convert about 80 percent of the energy into electricity. Wind and solar energy generators convert much less. Of course, another great benefit of tidal power renewable energy is that it is environmentally friendly. There are no CO2 emissions that are damaging to the atmosphere or Sulfur Dioxide emissions responsible for acid rain.
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