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carpenteraut98

Fuel Cells Save Money, Fuel and Mother Earth | ReTechnology Power and Water Engineering - 0 views

  • Although fuel cells are more expensive than fossil fuels, it is predicted that in the near future, fuel cell power will be less expensive and more efficient. The cost is an enticing advantage for the future.
  • The only emission is water vapor, a lot environment-friendly than the toxic elements released into the air by burning fossil fuels and gasoline burning cars.
  • The only waste product is water vapor.
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    "Although fuel cells are more expensive than fossil fuels, it is predicted that in the near future, fuel cell power will be less expensive and more efficient. The cost is an enticing advantage for the future."
westkea00

Energy Resources: Wave power - 3 views

  • Waves are a powerful source of energy.
  • The problem is that it's not easy to harness this energy and convert it into electricity in large amounts.
  • wave power stations are rare
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  • Once you've built a wave power station, the energy is free, needs no fuel and produces no waste or pollution
  • The energy is free - no fuel needed, no waste produced.
  • Not expensive to operate and maintain.
  • Can produce a great deal of energy.
  • Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem.
  • Ocean waves are caused by the wind as it blows across the sea. Waves are a powerful source of energy.
  • Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem
  • At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a turbine in this hole, which is turned by the air rushing in and out. The turbine turns a generator. A problem with this design is that the rushing air can be very noisy, unless a silencer is fitted to the turbine. The noise is not a huge problem anyway, as the waves make quite a bit of noise themselves.
  • At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a turbine in this hole, which is turned by the air rushing in and out. The turbine turns a generator. A problem with this design is that the rushing air can be very noisy, unless a silencer is fitted to the turbine. The noise is not a huge problem anyway, as the waves make quite a bit of noise themselves.
  • A company called Pelamis Wave Power are developing a method of offshore wave energy collection, using a floating tube called "Pelamis"
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    " Advantages   The energy is free - no fuel needed, no waste produced. Not expensive to operate and maintain. Can produce a great deal of energy. Disadvantages Depends on the waves - sometimes you'll get loads of energy, sometimes almost nothing. Needs a suitable site, where waves are consistently strong. Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem. Must be able to withstand very rough weather."
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    One of them works like a swimming pool wave machine in reverse. At a swimming pool, air is blown in and out of a chamber beside the pool, which makes the water outside bob up and down, causing waves.  
kenyonlau99

Where Does Solar Energy Come From - PV Gap - 0 views

  • Solar energy is energy from the sun, it is a renewable source of energy and does not cause pollution.
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    where does solar/photovoltaic energy come from? answer above!
behanjos99

What are geothermal energy advantages and disadvantages? - 0 views

  • Advantages: Geothermal energy cost is extremely low compared to many other energy sources. It has low pollution compared to fossil fuels and nuclear energy. Geothermal energy is a renewable energy source. Almost no environmental impact when using geothermal heat from nuclear decay. Geothermal heat pump systems can reduce your energy use storing heat from the summer/sun and makes use of it in the night and winter. Low maintenance systems.
  • Disadvantages: The most important disadvantage is absolutely the geological problem.  The heat source is mostly close to volcanic activity of some sort. Chemicals are byproducts of the production electricity with hot ground water. Some geothermal plants use a lot of water and it needs to go somewhere its after use. Some of the poluting chemicals in that water and steam are sulfur, mercury, hydrogen sulfide, arsenic, ammonia. Earth is a changing creature.  A drilled hole in the ground could supply thousands of homes heat and one earthquake could change that in a second.  It can also change gradually over time. Location, location, location.  That is certainly true of geothermal energy.  It cannot be transported over vast distances.  If used to heat up houses or for hot tap water it is only the quality of the pipe that delivers the water that determines how far it can go and if it will be of any use when it arrives. If the heat is used for electrical production it helps to have plants close so the energy loss is not too great. 
  • Corrosion is a big problem.  Composition of the chemicals can vary but it is always a problem.  It is among other the reason they need to heat up clean water to use and do not use it directly in to heating of houses.  In cases it has been used directly it causes pipes to corrode. In nuclear heating rock the rock cools down over few decades and hundreds of years are needed to get initial heating back.  Power stations of that sort are therefore not considered as profitable. Geothermal Heat pump systems do have high installation cost. Some areas run out of water or run low on ground water during seasonal dry spells. Less water means less heat and less energy to produce. Some drilling sites are too hot to handle.  Yea. Drillers have actually tried and tried some holes and they just can’t get the needed equipment in because the holes shoot it out like guns.   With workers running to stay alive while steel rains down on them. 
carpenteraut98

How Are Hydrogen Fuel Cells Affecting the Environment? | eHow.com - 0 views

  • por and a small amou
  • Unlike internal combustion and the burning of fossil fuels, hydrogen fuel cells do not produce particulates or emissions other than water vapor and a small amount of carbon dioxide.
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    "hydrogen fuel cells do not produce particulates or emissions other than water vapor and a small amount of carbon dioxide."
rodriguezjos99

Five Reasons Why Tidal Energy is the Wave of the Future - Green Living Ideas - 3 views

  • Green energy has never been more important than it is today with the looming threat of global warming. Every possible effort must be made to reverse the worldwide threat of climate change by subsidizing and switching to green energy. One often-overlooked source of clean, renewable energy comes not from solar, wind or geothermal power, but from the tides.
  • Tidal Energy is valuable to environmentalists because unlike fossil fuels the source of energy will not be depleted in the foreseeable future no matter how much energy is collected.
  • The collection of tidal energy is clean because it involves very little emission of carbon dioxide and other greenhouse gases
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  • The pattern of tides is extremely stable and not strongly affected by weather conditions which suggests that it would be a very stable source of green energy.
  • Moving water can exert a much greater force on a turbine than wind which means the turbine can turn slowly and still produce a great deal of electricity. The slow and stable tidal forces are ideal parameters for engineering energy solutions. The fact that the turbines can be slow-moving makes it easier to avoid interfering with local ecosystems
  • While the initial cost of building tidal energy plants is high, the plants are expected to run for a very long time which will make them more cost-effective in the long run
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    "Five Reasons Why Tidal Energy is the Wave of the Future JANUARY 4, 2013 BY GUEST CONTRIBUTOR LEAVE A COMMENT Join GLI's 10,000 other followers on Twitter! Green energy has never been more important than it is today with the looming threat of global warming. Every possible effort must be made to reverse the worldwide threat of climate change by subsidizing and switching to green energy. One often-overlooked source of clean, renewable energy comes not from solar, wind or geothermal power, but from the tides. 1. Tidal Energy is Renewable Tidal Energy is valuable to environmentalists because unlike fossil fuels the source of energy will not be depleted in the foreseeable future no matter how much energy is collected. The gravitational relationship between the Earth and the moon is extremely stable in the long term just like solar, wind and geothermal energy. 2. Tidal Energy is Green The collection of tidal energy is clean because it involves very little emission of carbon dioxide and other greenhouse gases. However, the marine ecosystem is fragile and great care must be taken to avoid interfering with the lives of organisms that depend on the tide."
bishophan00

Wind Power Information, Wind Power Facts - National Geographic - 1 views

  • Wind is a clean source of renewable energy that produces no air or water pollution.
  • Wind is the movement of air from an area of high pressure to an area of low pressure. In fact, wind exists because the sun unevenly heats the surface of the Earth. As hot air rises, cooler air moves in to fill the void. As long as the sun shines, the wind will blow. And as long as the wind blows, people will harness it to power their lives.
  • The wind spins the blades, which turn a shaft connected to a generator that produces electricity. Other turbines work the same way, but the turbine is on a vertical axis and the blades look like a giant egg beater.
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  • At the end of last year, global capacity was more than 70,000 megawatts.
  • And since the wind is free, operational costs are nearly zero once a turbine is erected.
  • Globally, generation more than quadrupled between 2000 and 2006.
  • n the energy-hungry United States, a single megawatt is enough electricity to power about 250 homes.
  • ndustry experts predict that if this pace of growth continues, by 2050 the answer to one third of the world's electricity needs will be found blowing in the wind.
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    where wind energy come from
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    ". At the end of last year, global capacity was more than 70,000 megawatts. In the energy-hungry United States, a single megawatt is enough electricity to power about 250 homes. "
mcdermottaar99

Generate Your Own Wind Energy - 0 views

  • As with installing your own solar energy, installing wind energy will help to reduce carbon emissions, which damage the environment and will save money.
  • It's only downfall is possibly the visual impact it makes on the landscape: A tall 'small scale' generator could attract wide rebuttal from neighbours, and this is worth considering before embarking on a wind generation project. However, if you live in a remote area, which benefits from exposure to the wind, or have neighbours that are happy for you to go ahead with the project, installing wind power can be an economically viable way to capitalise on natural, renewable resources
  • A wind generator will cost in the region of £3'000 - £15'000, at about £3'000 per kilowatt.
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  • You can expect a wind generator to pay for itself in little over five years, and with conventional energy prices soaring, the dividends will increase with time.
tvedepai00

Devices that Harness Wave Energy | Wave Energy Cost - 2 views

  • Wave energy is an irregular and oscillating low-frequency energy source that can be converted to a 60-Hertz frequency
  • Kinetic energy, the energy of motion, in waves is tremendous. An average 4-foot, 10-second wave striking a coast puts out more than 35,000 horsepower per mile of coast.
  • Because wave energy needs only 1/200 the land area of wind and requires no access roads, infrastructure costs are less;
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  • It varies in intensity, but it is available twenty-four hours a day, 365 days a year.
  • or now, the best wave generator technology in place in the United Kingdom is producing energy at an average projected/assessed cost of 7.5 cents kWh. In comparison, electricity generated by large scale coal burning power plants costs about 2.6 cents per kilowatt-hour.
  • As long as
  • the sun shines, wave energy will never be depleted
  • produce energy at about 4.5 cents kWh.
  • 7.5 cents kWh
  • In comparison, electricity generated by large scale coal burning power plants costs about 2.6 cents per kilowatt-hour.
  • about 3 cents per kilowatt hour
  • Wave energy devices are quieter and much less visually obtrusive than wind devices
mchughkon99

Directory:Cents Per Kilowatt-Hour - PESWiki - 0 views

  • 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. NuclearCurrently supplies around 24% of the global electricity demand. 11.1 - 14.5 Cents/kW-h Political difficulties in using nuclear in some nations. Risk of widespread (and potentially lethal) contamination upon containment failure. Fuel is plentiful, but problematic. Waste disposal remains a significant problem, and de-commissioning is costly (averaging approximately US $320MM per plant in the US).
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    cost for fossil fuels
dpurdy

How Does CO2 Cause Global Warming? | eHow.com - 0 views

  • Carbon dioxide contributes to global warming by absorbing heat energy from the earth, trapping it and preventing its release into space.
sconzomic99

Climate Change: Causes - 0 views

dpurdy

HowStuffWorks "Do wind turbines kill birds?" - 0 views

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    Do wind generators kill birds?
dpurdy

The hidden costs of fossil fuels - and biofuels, too - CSMonitor.com - 1 views

  • Climate considerations aside, damages wrought by ethanol made from corn were usually similar to, or even slightly worse, than damages from gasoline. That’s because of the extra energy needed to convert corn to biofuel.
sokolkyl00

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

  • Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
  • In one technique, long troughs of U-shaped mirrors focus sunlight on a pipe of oil that runs through the middle. The hot oil then boils water for electricity generation. Another technique uses moveable mirrors to focus the sun's rays on a collector tower, where a receiver sits. Molten salt flowing through the receiver is heated to run a generator.
  • Despite the drawbacks, solar energy use has surged at about 20 percent a year over the past 15 years, thanks to rapidly falling prices and gains in efficiency. Japan, Germany, and the United States are major markets for solar cells. With tax incentives, solar electricity can often pay for itself in five to ten years.
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  • Solar energy is lauded as an inexhaustible fuel source that is pollution and often noise free. The technology is also versatile.
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    " Today, the technology produces less than one tenth of one percent of global energy demand."
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    Intriguing facts about the suns energy on how they use it on oil and the drawback 
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    Every hour the sun beams onto Earth more than enough energy to satisfy global energy needs for an entire year. Solar energy is the technology used to harness the sun's energy and make it useable. Today, the technology produces less than one tenth of one percent of global energy demand.
dpurdy

How we know human activity is causing warming | Environmental Defense Fund - 1 views

  • The theory of global warming is nothing new. The Nobel Prize-winning chemist Svante Arrhenius first proposed the idea of global warming in 1896. Carbon dioxide, he knew, traps heat in the Earth's atmosphere. He also knew that burning coal and oil releases carbon dioxide (CO2).
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