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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.
dpurdy

Wave Energy: an Overview (Oxfordshire Climate Exchange) - 1 views

climatex.org/...wave-energy-overview

wave potential future how form history

shared by dpurdy on 30 Oct 12 - No Cached
  • Waves are generated by winds blowing over the ocean surface.  Wave energy is effectively a stored and concentrated form of solar energy since the winds that produce them are caused by pressure differences in the atmosphere caused by the sun's differential heating of the earth's surface. Waves can efficiently transport energy for thousands of miles and retain their energy long after the winds that first created them have died down, which makes waves one of the most concentrated and consistent sources of renewable energy. 
  • Globally, the potential use of wave power is, unsurprisingly, limited to areas of the world where there are waves. On a global scale, this is dictated by global wind patterns, with the result that waves are more prevalent in the mid-latitudes (40-60(N/S), than nearer the equator where the lack of ocean wind is referred to as the 'doldrums'.  Interestingly, this potential for wave power contrasts with that of solar power, which is more effective in lower latitudes
    • dpurdy
      dpurdy on 30 Oct 12
       
      Location of wave power.
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  • it is widely anticipated that other types of renewable resources, including wave energy, will need to be developed in order to meet more challenging targets beyond 2020. 
  • As with most renewable energy sources, wave devices have no emissions during generation but the energy associated with the construction of the device does have small associated emissions.
    • dpurdy
      dpurdy on 30 Oct 12
       
      What do we need to do in the future to make this work.
  • it is essential that the current demonstration schemes are successful, to reassure future investors. The most important objective is to deploy full-size demonstration schemes in order to gain greater confidence in the most developed technologies (as in the EU's Atlas project). 
  • it will be necessary to significantly improve the network connections to the electricity suppliers.
dpurdy

Succeeding in the 21st Century -- Skills and Abilities for the Future TCA paper - 0 views

www.coedu.usf.edu/...tca_paper.htm

all

shared by dpurdy on 24 Oct 12 - No Cached
  • The exchange of thoughts and ideas by speech or writing
  • Cooperative effort within a group in order to achieve a desired goal
  • To give rise to imaginative or artistic abilities as well as the ability to find novel solutions to problems
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  • Training or control over one's conduct for personal improvement as well as the ability to forgo immediate pleasure for long term goals
  • The ability to discern factual from opinionated information
  • The effective use of grammatical rules and guidelines in order to express one's ideas in correct form
  • bility to use computer technology effectively, including word-processing and spreadsheets
  • The ability to use the defined principles of logic and effectively engage in abstract thinking to achieve mastery or understanding
conwayjam99

World of Wind Energy.com - The World's #1 Wind Energy Site! - News - WIND ECOLOGY AND P... - 1 views

www.worldofwindenergy.com/vbnews.php

pollution tubines

shared by conwayjam99 on 15 Mar 12 - No Cached
  • Wind power is a renewable resource, which means using it will not deplete the earth's supply of fossil fuels. It also is a clean energy source, and operation does not produce carbon dioxide, sulfur dioxide, mercury, particulates, or any other type of air pollution, as do conventional fossil fuel power sources.
  • Wind power consumes no fuel for continuing operation, and has no emissions directly related to electricity production.
  • Wind power's ability to reduce pollution and greenhouse gas emissions will depend on the amount of wind energy produced, and hence scalability.
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  • Wind power may also have an indirect effect on pollution at other production facilities, due to the need for reserve and regulation, and may affect the efficiency profile of plants used to balance demand and supply, particularly if those facilities use fossil fuel sources. Compared to other power sources, however, wind energy's direct emissions are low, and the materials used in construction (concrete, steel, fiberglass, generation components) and transportation are straightforward.
  • Wind power's ability to reduce pollution and greenhouse gas emissions will depend on the amount of wind energy produced, and hence scalability.
  • Wind power may also have an indirect effect on pollution at other production facilities, due to the need for reserve and regulation, and may affect the efficiency profile of plants used to balance demand and supply, particularly if those facilities use fossil fuel sources. Compared to other power sources, however, wind energy's direct emissions are low, and the materials used in construction (concrete, steel, fiberglass, generation components) and transportation are straightforward.
  • carbon dioxide, sulfur dioxide, mercury, particulates, or any other type of air pollution, as do conventional fossil fuel power sources.
  • conwayjam99 on 13 Mar 13
     
    " United States, onshore and near-shore turbines kill 70,000 birds per year, compared to 57 million killed by cars and 97.5 million killed by collisions with plate glass."
smithree98

Hydrogen Fuel-Cell Vehicles - Is Hydrogen the Fuel of the Future? - 1 views

environment.about.com/...fcv.htm

hydrogen fuel all benifits

shared by smithree98 on 15 Mar 12 - No Cached
  • The benefits of ditching fossil fuels for hydrogen are many, of course. Burning fossil fuels like coal, natural gas and oil to heat and cool our buildings and run our vehicles takes a heavy toll on the environment, contributing significantly to both local problems such as elevated particulate levels and global ones such as a warming climate. The only by-product of running a hydrogen-powered fuel cell is oxygen and a trickle of water, neither of which will cause any harm to human health or the environment.
  • But right now, 95 percent of the hydrogen available in the United States is either extracted from fossil fuels or made using electrolytic processes powered by fossil fuels, thus negating any real emissions savings or reduction in fossil-fuel usage. Only if renewable energy sources—solar, wind and others—can be harnessed to provide the energy to process hydrogen fuel can the dream of a truly clean hydrogen fuel be realized.
  • They concluded that we’d lower greenhouse gas emissions more by driving gasoline/electric hybrid cars than by driving fuel-cell cars run on hydrogen from coal. Hydrogen made using natural gas would fare a little bit better in terms of pollution output, while making it from wind power would be a slam-dunk for the environment.
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  • replacing the fossil fuels responsible for global warming and various nagging forms of pollution.
  • Another problem is the lack of hydrogen refueling stations
  • many reasons, ranging from safety to cost to lack of demand.
  • they are spending upwards of $1 million to produce each one due to the advanced technology involved and low production runs. Toyota hopes to reduce its costs per fuel-cell vehicle to around $50,000 by 2015
  • smithree98 on 22 Oct 12
     
    says most things about hydrogen and what it does
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.
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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
  • 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."
dpurdy

Winds, Waves, Tides - Ocean Energy | Environmental News, Articles & Information | Globa... - 2 views

www.ecoworld.com/...-waves-tides-ocean-energy.html

cost how what sustainable future

shared by dpurdy on 03 Nov 11 - No Cached
  • Can Already Cost Under $.06 per Kilowatt Hour * Pneumatic devices, such as the oscillating water column (OWC), use wave motion to compress and decompress air, and drive a turbine. * Float-based devices utilise a buoyant float moving with the waves, reacting against a sea bed anchor in order to harness energy. * Spillover devices utilise wave height to replenish a reservoir of seawater, which runs a turbine. * Raft-type devices use the relative motion of adjacent rafts or pontoons to harness wave energy. * Moving-body devices articulate in the water, inducing motion, which may be used to drive a hydraulic motor.
  • Tidal stream devices extract energy from the diurnal flow of tidal currents (caused by the gravitational pull of the moon). Unlike wind and wave power, tidal streams offer entirely predictable output. However, as the lunar cycle is of around 25 hours’ duration, the timing of peak outputs differs by around an hour each day and tidal energy cannot be guaranteed at times of peak demand.
  • However, several large grid-connected demonstration projects are expected to enter the water in the near future. Tidal stream is thus a few years behind wave energy.
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  • Marine Current Turbines is about to field test a submerged 300 kW tidal turbine off Devon in the United Kingdom
  • The manufacturers of all these devices expect to deliver energy at a cost of 10-14 US cents per kWh, falling to below 6 US cents as experience grows and technologies mature
  • Power generation using wave energy is at a much earlier stage of development. Wave energy offers more predictable outputs than wind, but in early 2003 there was only around one megawatt of generating capacity installed worldwide, all of it essentially with demonstration prototypes. Proposed projects are likely to take this to about 6 MW over the next few years. The wave industry is characterised by a wide variety of novel devices
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 - Hydropower - 1 views

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

what how location

shared by dpurdy on 03 Nov 11 - No Cached
  • Tides are caused by the gravitational pull of the moon and sun, and the rotation of the Earth. Near shore, water levels can vary up to 40 feet due to tides. Dam of the Tidal Power Plant on the Estuary of the Rance River, Bretagne, France Source: Stock photography (copyrighted) Tidal power is more predictable than wind energy and solar power. A large enough tidal range — 10 feet — is needed to produce tidal energy economically.
  • The United States has no tidal plants and only a few sites where tidal energy could be produced economically. France, England, Canada, and Russia have much more potential to use this type of energy.
  • Tidal turbines are basically wind turbines in the water that can be located anywhere there is strong tidal flow. Because water is about 800 times denser than air, tidal turbines have to be much sturdier than wind turbines. Tidal turbines are heavier and more expensive to build but capture more energy.
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  • Waves are caused by the wind blowing over the surface of the ocean. There is tremendous energy in the ocean waves. It's estimated that the total potential off the coasts of the United States is 252 billion kilowatthours a year, about 6% of the United States' electricity consumption in 2010. The west coasts of the United States and Europe and the coasts of Japan and New Zealand are good sites for harnessing wave energy.
  • Many more ways to capture wave energy are currently under development. Some of these devices being developed are placed underwater, anchored to the ocean floor, while others ride on top of the waves. The world's first commercial wave farm using one such technology opened in 2008 at the Aguçadora Wave Park in Portugal.
  • anonymous on 28 Sep 13
     
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whalenkil98

Photovoltaics - Timeline of the History of Photovoltaics - 0 views

inventors.about.com/...Photovoltaics.htm

solar convert

shared by whalenkil98 on 12 Mar 13 - Cached
  • 1839: Nineteen-year-old Edmund Becquerel, a French experimental physicist, discovered the photovoltaic effect while experimenting with an electrolytic cell made up of two metal electrodes. 1873: Willoughby Smith discovered the photoconductivity of selenium.
  • kenyonlau99 on 12 Mar 13
     
    "Today's photovoltaic systems are used to generate electricity to pump water, light up the night, activate switches, charge batteries, supply power to the utility grid, and much more. 1839: Nineteen-year-old Edmund Becquerel, a French experimental physicist, discovered the photovoltaic effect while experimenting with an electrolytic cell made up of two metal electrodes. 1873: Willoughby Smith discovered the photoconductivity of selenium. 1876: Adams and Day observed the photovoltaic effect in solid selenium. 1883: Charles Fritts, an American inventor, described the first solar cells made from selenium wafers. 1887: Heinrich Hertz discovered that ultraviolet light altered the lowest voltage capable of causing a spark to jump between two metal electrodes. 1904: Hallwachs discovered that a combination of copper and cuprous oxide was photosensitive. Einstein published his paper on the photoelectric effect. 1914: The existence of a barrier layer in PV devices was reported. 1916: Millikan provided experimental proof of the photoelectric effect. 1918: Polish scientist Czochralski developed a way to grow single-crystal silicon. 1923: Albert Einstein received the Nobel Prize for his theories explaining the photoelectric effect. 1951: A grown p-n junction enabled the production of a single-crystal cell of germanium. 1954: The PV effect in Cd was reported; primary work was performed by Rappaport, Loferski and Jenny at RCA. Bell Labs researchers Pearson, Chapin, and Fuller reported their discovery of 4.5% efficient silicon solar cells; this was raised to 6% only a few months later (by a work team including Mort Prince). Chapin, Fuller, Pearson (AT&T) submitted their results to the Journal of Applied Physics. AT&T demonstrated solar cells in Murray Hill, New Jersey, then at the National Academy of Science Meeting in Washington, DC. 1955: Western Electric began to sell commercial licenses for silicon PV technologies; early successful products included PV-powered dolla
dpurdy

EnergyBC: Tidal Power - 2 views

www.energybc.ca/...tidal.html

tide form convert history

shared by dpurdy on 12 Mar 13 - No Cached
  • his is somewhat balanced out by long plant lives of 100 years for the actual barrage structure, and 40 for the equipment, as well as low operating costs.
  • An estimate is given by researcher Eleanor Denny. Denny estimates that in order for a facility to be profitable, its capital cost should be less than €530,000 (~$700,000 USD) per MegaWatt which with the current technology is not a realistic goal, meaning that so far the industry produces negative net benefits.50
  • Canada's Race Rocks site, where a single turbine generator converts 65 kW of energy, cost $4,000,000.54 This figure was met with $3,000,000 investment from project partner EnCana's Environmental Innovation Fund, and a grant of just under $1 million awarded to Pearson College and their partners in the project.
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  • This plant produces about 100 times the power generated at Race Rocks. An investment of around €8.5 million ($11 million USD) made SeaGen a reality.
  • , they are, by nature, reliant on the natural environment and therefore are vulnerable to the effects of climate change
  • sustainable energy resources produce limited amounts of carbon dioxide emissions
  • The environmental impacts of tidal barrage include hampered fish migration, forced water level changes on the basin behind the barrage, reduced salinity in the basin due to low quantities of ocean water, and reduced ability of currents to transport and suspend sediments
  • Brief History of Tidal Power The energy stored in tides been known to people for many centuries. The earliest records of tidal mills are dated back to the 8th Century CE.7 The tidal mills were mainly used for grain grinding and were of similar design to the conventional water mills with the exception of the addition of a dam and reservoir. The industrial revolution increased demand for power but tidal energy never got off the ground, undercut by cheap fossil fuels and other developments which offered easier access to power generation. Existing tidal mills became as obsolescent as pre-industrial water-mills. The first large scale modern tidal electric plant started to operate in La Rance Estuary, St. Malo, France in the 1960s and has been operating ever since. In recent years the search for renewable, non-polluting energy sources and the increase in fossil fuel prices has encouraged renewed interest in tidal power.
westkea00

Energy Basics: Wave Energy - 0 views

www.eere.energy.gov/...wave_energy.html

shared by westkea00 on 12 Mar 13 - No Cached
  • Offshore Systems Offshore systems are situated in deep water, typically of more than 131 feet (40 meters). Sophisticated mechanisms—such as the Salter Duck—use the bobbing motion of the waves to power a pump that creates electricity. Other offshore devices use hoses connected to floats that ride the waves. The rise and fall of the float stretches and relaxes the hose, which pressurizes the water, which, in turn, rotates a turbine. Specially built seagoing vessels can also capture the energy of offshore waves. These floating platforms create electricity by funneling waves through internal turbines and then back into the sea. Onshore Systems Built along shorelines, onshore wave power systems extract the energy of breaking waves. Onshore system technologies include: Oscillating Water Columns: Oscillating water columns consist of a partially submerged concrete or steel structure that has an opening to the sea below the waterline. It encloses a column of air above a column of water. As waves enter the air column, they cause the water column to rise and fall. This alternately compresses and depressurizes the air column. As the wave retreats, the air is drawn back through the turbine as a result of the reduced air pressure on the ocean side of the turbine. Tapchans: Tapchans, or tapered channel systems, consist of a tapered channel that feeds into a reservoir constructed on cliffs above sea level. The narrowing of the channel causes the waves to increase in height as they move toward the cliff face. The waves spill over the walls of the channel into the reservoir, and the stored water is then fed through a turbine. Pendulor Devices: Pendulor wave-power devices consist of a rectangular box that is open to the sea at one end. A flap is hinged over the opening, and the action of the waves causes the flap to swing back and forth. The motion powers a hydraulic pump and a generator.
  • Wave energy technologies extract energy directly from surface waves or from pressure fluctuations below the surface. Renewable energy analysts believe there is enough energy in ocean waves to provide up to 2 terawatts of electricity. (A terawatt is equal to a trillion watts.)
brownale99

How is geothermal energy better than fossil fuels - 1 views

wiki.answers.com/...nergy_better_than_fossil_fuels

geothermal sustainable

shared by brownale99 on 12 Mar 13 - No Cached
  • brownale99 on 12 Mar 13
     
    "Geo thermal systems heat and cool your house cheaper and better than fossil fuels will with gas going up pretty soon you would not be able to afford it. It might be costly to put one in your house initially but it will pay itself off in 3-5 years. Also there is a company called ECONAR that builds a heat pump that will cool, heat, and do 50 to 100% of your hot water heat. Fossil fuels also produce carbon dioxide when burnt, adding to the greenhouse gases and contributing to climate change."
crandallmad00

How Tidal Power is Riding the Crest of a Wave - 1 views

www.renewableenergyworld.com/...-is-riding-the-crest-of-a-wave

tide wave

shared by crandallmad00 on 12 Mar 13 - No Cached
  • The argument for tidal power is overwhelming: it’s a practically infinite supply of clean energy and has one of the smallest carbon footprints of any power source; it’s reliable, cost-efficient, has minimal effect on the marine environment and virtually zero effect on sea-gazing aesthetics. Most importantly, The World Energy Council estimates that the energy that can be harvested from world’s oceans is equal to twice the electricity that the world produces now
  • A reason many energy experts are looking at what tidal may be able to contribute, compared to other renewable sources like wind power, is that the amount of energy generated from a power-generating turbine is proportional to the density of the fluid that flows back and forth – meaning a water turbine has several hundred times the power of an air turbine.
  • Seawater is denser than air; a lot denser – 832 times to be exact, meaning an 8 knot tidal current has more energy than a 380kph wind. This means a wave farm of ‘sea snakes’ – devices built by Scotland’s Pelamis Wave Power – covering half a square mile of ocean could produce 30 MWh of power, which is estimated to be enough for 20,000 homes. A wave farm covering 472 square miles could supply 24 million households – enough for the entire UK.
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  • Partly this has been due to the uncertainty of how to harness all this abundant marine energy. While it’s great that there’s the potential to harness up to 153 GW of tidal power in the UK alone,
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
westkea00

Ocean Wave Energy Power Technology - History - 0 views

clean-future.com/...wave-power

shared by westkea00 on 06 Apr 13 - No Cached
  • Currently, numerous wave power plants (so called wave farms) have been implemented throughout the world. Many different organizations have designed various wave power systems that differ in size, cost, and effectiveness. A wave farm is a collection of wave power systems in order to create mass quantities of power. One example of a wave power plant is the Aguçadoura Wave Farm in Portugal from Pelamis Wave Power Ltd. It is the first wave farm ever established and produces 2.25 megawatts of power. It was completed in 2008. Other wave farms, with other companies involved, have been proposed.
  • Wave energy is about using the energy of ocean waves for producing electrical current. It is a renewable energy resource and often confused with Tidal Power.
  • Wave energy is considered a form of hydropower, although it is the wind blowing over the surface of the ocean causing waves. So in many ways, wave energy is also wind energy - with all the pros and cons.
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  • In contrast to tidal power, ocean wave energy plants do not make use of the energy difference between high tide and low tide, but generating energy from continuous wave motion. So, wave energy generation is the conversion of the forces from the motion of waves into usable energy.
  • Wave power generation has been tested over the past century as an alternative energy source to fossil fuels to create electrical power, sea water desalinization, and reservoir pumping. Unfortunately, despite of all examinations and tests, the price for generating energy from ocean waves is still about twice as high as that of wind energy. Companies involved in wave energy generation hope to be able to cut 50% of the costs within the next couple of years.
  • During the 1970's gasoline crisis, wave power was pushed in order to be a good long term energy solution. Later, the energy crisis was resolved yet the leaps and bounds made in the innovation of wave power remained. Though there were not many wave power plants actually implemented, it has proven to be a benefit to modern resolutions with current power crises. Fuel prices are rising exponentially and the greenhouse effect is having potentially disastrous effects on the environment. There has never been more need for alternatives to fossil generated energy.
brownale99

Green Rock Energy - Geothermal Energy - Sustainability - 0 views

www.greenrock.com.au/geothermalSustainability.php

geothermal sustainable

shared by brownale99 on 22 Oct 12 - No Cached
  • The Benefits "Geothermal energy has the potential to generate and deliver sustainable supplies of clean, renewable base load power. Depending on the nature of the resource and the reservoir, individual production wells have the potential to generate consistent supplies of base load power for decades."
  • Geothermal energy has the potential to generate and deliver sustainable supplies of clean, renewable base load power.
  • individual production wells have the potential to generate consistent supplies of base load power for decades.
  • ...2 more annotations...
  • Base load electricity generated from geothermal energy is clean, renewable and has minimal impact on the environment.
  • Unlike burning fossil fuels, the process emits no greenhouse gases, pollution or hazardous wastes.
  • messinaaar98 on 22 Oct 12
     
    "The Benefits "Geothermal energy has the potential to generate and deliver sustainable supplies of clean, renewable base load power. Depending on the nature of the resource and the reservoir, individual production wells have the potential to generate consistent supplies of base load power for decades.""
  • gazdiknic99 on 11 Mar 13
     
    main idea, supporting facts, and conclusion
  • brownale99 on 11 Mar 13
     
    ""Geothermal energy has the potential to generate and deliver sustainable supplies of clean, renewable base load power. Depending on the nature of the resource and the reservoir, individual production wells have the potential to generate consistent supplies of base load power for decades.""
dpurdy

Huge challenges in scaling up biofuels infrastructure - 1 views

www.physorg.com/news201799021.html

biofuel infrastructure potential

shared by dpurdy on 22 Mar 12 - No Cached
  • Major changes will be needed to grow, handle, transport and store the immense quantities of biomass -- mostly lignocellulosic feedstocks such as switchgrass, crop residues and forest wastes -- necessary to continually feed electric power generation stations and produce biofuels for transportation,
  • converting to a system in which biomass provides much of the country's energy will require new ways of thinking about agriculture, energy infrastructure and rural economic development.
  • It is estimated that bioenergy has the potential to provide up to 60 percent of the world's primary energy, and biomass seems poised to provide a major alternative to fossil fuels,"
  • ...2 more annotations...
  • "Thus, the combination of expected growth in energy demand and the lower density of biomass imply that by 2050, biomass transport volumes will be greater than the current capacity of the entire energy and agricultural commodity infrastructure,
  • "For example, a large biofuel plant would require 16 to 20 tanker trucks or railcars per day to move the fuel to market, increasing both traffic and costs."
dpurdy

EIA Energy Kids - Solar - 2 views

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

solar what location pollution how history sustainable

shared by dpurdy on 03 Nov 11 - No Cached
  • Energy from the Sun The sun has produced energy for billions of years.  Solar energy is the sun’s rays (solar radiation) that reach the Earth. This energy can be converted into other forms of energy, such as heat and electricity.
  • Photovoltaic (PV devices) or “solar cells” change sunlight directly into electricity. Individual PV cells are grouped into panels and arrays of panels that can be used in a wide range of applications ranging from single small cells that charge calculator and watch batteries, to systems that power single homes, to large power plants covering many acres.
  • Solar energy systems do not produce air pollutants or carbon-dioxide
  • ...5 more annotations...
  • Solar energy is by far the Earth's most available energy source. Solar power is capable of providing many times the total current energy demand. But it is an intermittent energy source, meaning that it is not available at all times.
  • Photons Carry Solar Energy Sunlight is composed of photons, or particles of solar energy. These photons contain various amounts of energy corresponding to the different wavelengths of the solar spectrum. When photons strike a photovoltaic cell, they may be reflected, pass right through, or be absorbed. Only the absorbed photons provide energy to generate electricity. When enough sunlight (energy) is absorbed by the material (a semiconductor), electrons are dislodged from the material's atoms. Special treatment of the material surface during manufacturing makes the front surface of the cell more receptive to free electrons, so the electrons naturally migrate to the surface.
  • Weather Affects Photovoltaics The performance of a photovoltaic array is dependent upon sunlight. Climate conditions (such as clouds or fog) have a significant effect on the amount of solar energy received by a photovoltaic array and, in turn, its performance.
  • History of the Photovoltaic Cell The first practical photovoltaic (PV) cell was developed in 1954 by Bell Telephone researchers examining the sensitivity of a properly prepared silicon wafer to sunlight. Beginning in the late 1950s, PV cells were used to power U.S. space satellites. PV cells were next widely used for small consumer electronics like calculators and watches and to provide electricity in remote or "off-grid" locations were there were no electric power lines. Technology advances and government financial incentives have helped to greatly expand PV use since the mid-1990s.
  • Using solar energy produces no air or water pollution and no greenhouse gases, but does have some indirect impacts on the environment.
  • anonymous on 02 Oct 13
     
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dpurdy

EIA Energy Kids - Geothermal - 3 views

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

geothermal what location how pollution history sustainable

shared by dpurdy on 03 Nov 11 - No Cached
  • Geothermal Basics What Is Geothermal Energy? The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity. Geothermal energy is a renewable energy source because the heat is continuously produced inside the Earth.
  • Geothermal energy is generated in the Earth's core. Temperatures hotter than the sun's surface are continuously produced inside the Earth by the slow decay of radioactive particles, a process that happens in all rocks. The Earth has a number of different layers:
  • Where Geothermal Energy is Found The ring of fire goes around the edges of the Pacific. The map shows that volcanic activity occurs around the Pacific rim.Source: National Energy Education Development Project (Public Domain) Naturally occurring large areas of hydrothermal resources are called geothermal reservoirs. Most geothermal reservoirs are deep underground with no visible clues showing above ground. But geothermal energy sometimes finds its way to the surface in the form of: Volcanoes and fumaroles (holes where volcanic gases are released) Hot springs Geysers
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  • U.S. Geothermal Is Mostly in the West Most of the geothermal reservoirs in the United States are located in the western States and Hawaii.
  • Electricity generation power plants require water or steam at very high temperature (300° to 700°F). Geothermal power plants are generally built where geothermal reservoirs are located within a mile or two of the surface.
  • The United States Is the Leader in Geothermal Power Generation The United States leads the world in electricity generation with geothermal power.  In 2009, U.S. geothermal power plants produced 15 billion kilowatt-hours (kWh), or 0.4% of total U.S. electricity generation.  In 2009, five States had geothermal power plants:
  • Geothermal power plants use hydrothermal resources that have two common ingredients: water (hydro) and heat (thermal). Geothermal plants require high temperature (300°F to 700°F) hydrothermal resources that may come from either dry steam wells or hot water wells.
  • high-pressure hot water from deep inside the Earth and convert it to steam to drive the generator turbines. When the steam cools, it condenses to water and is injected back into the ground to be used over and over again. Most geothermal power plants are flash steam plants.
  • Geothermal Power Plants Have Low Emission Levels Geothermal power plants do not burn fuel to generate electricity, so their emission levels are very low. They release less than 1% of the carbon dioxide emissions of a fossil fuel plant. Geothermal plants use scrubber systems to clean the air of hydrogen sulfide that is naturally found in the steam and hot water. Geothermal plants emit 97% less acid rain-causing sulfur compounds than are emitted by fossil fuel plants. After the steam and water from a geothermal reservoir have been used, they are injected back into the Earth.
  • 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
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