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geczyluk99

A Pollution-Free Hydrogen Economy? Not So Soon | MIT Technology Review - 0 views

  • There’s a much cheaper way to produce hydrogen: spray steam on white-hot coals and out comes mostly hydrogen gas (40 percent) and carbon monoxide (50 percent), a mixture known appropriately as “water gas.” It’s the least expensive way to make hydrogen. Unfortunately, the carbon monoxide produced along with it is highly poisonous. To extract the last bit of energy, the carbon monoxide can be burned, and that turns it into the greenhouse gas carbon dioxide.
  • Electric cars powered by hydrogen fuel cells don’t produce greenhouse-enhancing carbon dioxide. But producing hydrogen does-and if we want to reduce our petroleum dependence, we’re going to have to reconcile ourselves to that fact.
kurishkri00

Wind Energy - 0 views

  • The wind turns the blades, which spin a shaft connected to the generator and produces electricity. Turbine blades are designed in such a way that wind causes them to rotate, which rotates the shaft at low speed, with a gear at the end that itself is connected to small gear on high speed shaft that runs through alternator housing.
  • he generator produces electricity using the same principle as a generator of your car (depending on the turbine). Magnetic Rotor inside the generator on high speed shaft spins inside loops of copper wire that are wound around an iron core. The rotor creates “electromagnetic induction” as it spins around the inside of the core through the coils, which generates electrical power. The current is regulated and transmission network (or home network system connection), after some changes, so it can use in our homes or sent to a battery bank for storage.
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    Most wind turbines turn in the moving air like blades of propeller aircraft and supply power to an electric generator that produces electricity. Wind turbines, rather than working as a fan in your house that uses electricity to generate wind, use wind power to generate electricity. - See more at: http://www.conserve-energy-future.com/Wind_Into_Energy.php#sthash.MFQJ5BOI.dpuf
mannixjul00

Fossils Fuels vs. Renewable Energy | Ecology Global Network - 1 views

  • Burning fossil fuels creates carbon dioxide, the number one greenhouse gas contributing to global warming. Combustion of these fossil fuels is considered to be the largest contributing factor to the release of greenhouse gases into the atmosphere. In the 20th century, the average temperature of Earth rose 1 degree Fahrenheit (1°F). This was a period that saw the most prolific population growth and industrial development
  • Some estimates say our fossil fuel reserves will be depleted within 50 years, while others say it will be 100-120 years.
  • Sun, wind and water are perfect energy sources…depending on where you are. They are non-polluting, renewable and efficient
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  • The object is to capture and harness their mechanical power and convert it to electricity in the most effective and productive manner possible.
  • Another form of hydroelectric energy is tidal power. In use since the early 1900s, tidal power stations collect the energy created by the rise and fall of the tides to convert to electricity.
    • mannixjul00
       
      history maybe?
bonnjos98

My Library - 0 views

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    ""It may surprise you to know that the ancient Romans had central heating. They used geothermal energy - in the form of hot springs - to heat their homes. Geothermal heating wasn't used in an organized fashion since until the late 19th century when Boise, Idaho, piped in water from local hot springs to warm buildings. Now, geothermal energy is used globally. Reykjavik, Iceland, leads the world in use of geothermal energy, heating 95 percent of its buildings with heat from below the Earth's surface." more from curiosity.discovery.com - Not Cached - Edit - Delete - Share▼ - Preview"
sokolkyl00

Solar power - Sustainable green energy to protect our economy and environment | PARTHA ... - 2 views

  • A Solar Energy system can operate entirely independently, not requiring a connection to a power or gas grid at all. Systems can therefore be installed in remote locations, making it more practical and cost-effective than the supply of utility electricity to a new site.
  • A Solar Energy system can operate entirely independently, not requiring a connection to a power or gas grid at all. Systems can therefore be installed in remote locations, making it more practical and cost-effective than the supply of utility electricity to a new site.
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    "It offers much more self-reliance than depending upon a power utility for all electricity."
dittrichcai99

AE Kids : Geothermal Energy - 0 views

  • o" means "from the earth," and "thermal" means "heat," so this type of energy is found under
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    "A geothermal heating system uses pipes buried more than four feet deep in the earth. That is another reason why it's important for adults to call 811 before they dig in their yard so they don't hit buried piping. The system pumps a liquid through the pipes to absorb the heat and brings it back indoors. A device called a "heat exchanger" takes the heat from the liquid and uses it to heat the air inside the home."
streetscor99

Fuel cells, what is a fuel cell, disadvantages, benefits - 0 views

  • * Because there is no combustion in a fuel cell, fuel is converted to electricity more efficiently than any other electrical generating technology available today. * There are no moving parts in a fuel cell stack, making them more reliable and quieter than generators. Even the ancillary systems (fans, pumps, controls, etcetera) in a complete fuel cell unit are relatively mature and simple technologies that should prove extremely reliable.
  • In the past, fuel cells were large and extremely expensive to manufacture, just as the first calculators and computers were. But, just like these products, the cost of fuel cells will quickly come down to consumer-affordable levels with mass production. We are currently in a transition period now, where many fuel cell companies are investing literally hundreds of millions of dollars to gear up for mass manufacturing at the same time they are trying to begin to develop a variety of markets for their product.
dpurdy

How do fossil fuels cause pollution - 1 views

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    "Fossil fuels, even when burned perfectly (natural gas, or methane, burns the best) release carbon dioxide which is a greenhouse gas causing dangerous global warming. Most fossil fuels also release smoke (leading to smog), and they may also release sulfur oxides and nitrogen oxides which contribute to acid rain."
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    "Fossil fuels, even when burned perfectly (natural gas, or methane, burns the best) release carbon dioxide which is a greenhouse gas causing dangerous global warming. Most fossil fuels also release smoke (leading to smog), and they may also release sulfur oxides and nitrogen oxides which contribute to acid rain."
mcgarrdan98

Geothermal Energy: Construction Impacts - 0 views

  • Emissions generated during the construction phase include exhaust from vehicular traffic and construction equipment, fugitive dust from traffic on paved and unpaved roads, and the release of geothermal fluid vapors (especially hydrogen sulfide, carbon dioxide, mercury, arsenic, and boron, if present in the reservoir). Activities such as site clearing and grading, power plant and pipeline system construction, and transmission line construction would have more intense exhaust-related emissions over a period of 2 to 10 years. Impacts would depend upon the amount, duration, location, and characteristics of the emissions and the meteorological conditions (e.g., wind speed and direction, precipitation, and relative humidity).
  • Most impacts to ecological resources (vegetation, wildlife, aquatic biota, special status species, and their habitats) would be low to moderate and localized during the construction phase (although impacts due to noise could be high). Activities such as site clearing and grading, road construction, power plant construction, ancillary facility construction, and vehicle traffic have the potential to affect ecological resources by disturbing habitat, increasing erosion and runoff, and creating noise at the project site. Impacts to vegetation include loss of native species and species diversity; increased risk of invasive species; increased risk of topsoil erosion and seed bank depletion; increased risk of fire; and alteration of water and seed dispersal.
  • Solid and industrial waste would be generated during construction activities. Much of the solid waste would be nonhazardous, consisting of containers and packaging materials, miscellaneous wastes from equipment assembly and presence of construction crews (food wrappers and scraps), and woody vegetation. Industrial wastes would include minor amounts of paints, coatings, and spent solvents. Most of these materials would likely be transported off-site for disposal.
ricciardellinick

Energy Studies - How Fuel Cell Works - 2 views

  • Hydrogen is the simplest of all elements with one electron and one proton. Two hydrogen atoms form one hydrogen gas molecule, or H2, but this gas is rarely found in large quantities in nature. Hydrogen’s chemical properties allow it to combine easily with other elements to form other molecules.
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    "Hydrogen is the simplest of all elements with one electron and one proton. Two hydrogen atoms form one hydrogen gas molecule, or H2, but this gas is rarely found in large quantities in nature. Hydrogen's chemical properties allow it to combine easily with other elements to form other molecules"
chakrabortyshi00

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

  • 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.
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  • 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
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    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.
jack wells

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

  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.
  • One of the most important is that wind power is the least expensive of all other forms of alternative energy. 
  • Another tremendous benefit of wind power is that it is a sustainable source of energy and a clean source of energy
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  • Wind energy is also a renewable energy, meaning it does not deplete our natural resources like coal or petroleum based products.
  • One of the most important is that wind power is the least expensive of all other forms of alternative energy.  Wind turbines generate electricity at around 5 cents per kWh (Kilowatt Hour), which is comparable to the new coal and/or oil burning power plants.  The costs are projected to decline even more as technology improves, and this is very important because most of the cost with wind power is in manufacturing.  Once the wind turbines are in place there is little cost to maintain and wind power is free.
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    The benefits of wind energy.
lemairenat98

Tidal stream power - Simple English Wikipedia, the free encyclopedia - 0 views

  • Tidal stream systems need to be located in areas with fast currents where natural flows are concentrated between obstructions, for example at the entrances to bays and rivers, around rocky points, headlands, or between islands or other land masses.
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    "Tidal stream systems need to be located in areas with fast currents where natural flows are concentrated between obstructions, for example at the entrances to bays and rivers, around rocky points, headlands, or between islands or other land masses."
phinneycha99

Energy and kids - 1 views

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    "Photovoltaic cells, like batteries, generate direct current (DC) which is generally used for small loads (electronic equipment).  When DC from photovoltaic cells is used for commercial applications or sold to electric utilities using the electric grid, it must be converted to alternating current (AC) using inverters, solid state devices that convert DC power to AC. "
sopranodan99

Wave & Tidal Energy Technology | Renewable Northwest Project - 0 views

  • Potential
  • Wave energy resources are best between 30º and 60º latitude in both hemispheres, and the potential tends to be the greatest on western coasts
  • While no commercial wave or tidal projects have yet been developed in the United States, several projects are planned for the near future, including projects in the Northwest
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  • ‘Pelamis’ wave energy conversion devices and generates a combined 2.25 MW of electricity. OPD plans to expand the facility to produce 22.5 MW in 2007
  • The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system.
  • Total Annual U.S. Incident Wave Energy 2,110 terrawatt-hours
  • The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system
  • In addition to its abundant solar, wind and geothermal resources, the Pacific Northwest is also uniquely situated to capture the renewable energy of the ocean. Special buoys, turbines, and other technologies can capture the power of waves and tides and convert it into clean, pollution-free electricity. Like other renewable resources, both wave and tidal energy are variable in nature. Waves are produced by winds blowing across the surface of the ocean. However, because waves travel across the ocean, their arrival time at the wave power facility may be more predictable than wind. In contrast, tidal energy, which is driven by the gravitational pull of the moon and sun, is predictable centuries in advance.
  • The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system
  • The Unit
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    the amount of 1/4 of energy around the coasts could be equal to the amount energy produced by hydropower
filionmar99

Group items tagged pollution - qmstech2 | Diigo Groups - 0 views

    • filionmar99
       
      read this
  • The major challenge to using wind as a source of power is that it is intermittent and does not always blow when electricity is needed. Wind cannot be stored (although wind-generated electricity can be stored, if batteries are used), and not all winds can be harnessed to meet the timing of electricity demands. Further, good wind sites are often located in 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.
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  • A Renewable Non-Polluting Resource Wind energy is a free, renewable resource, so no matter how much is used today, there will still be the same supply in the future. Wind energy is also a source of clean, non-polluting, electricity. Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases. According to the U.S. Department of Energy, in 1990, California's wind power plants offset the emission of more than 2.5 billion pounds of carbon dioxide, and 15 million pounds of other pollutants that would have otherwise been produced. It would take a forest of 90 million to 175 million trees to provide the same air quality.
sokolkyl00

Sustainable energy - Wikipedia, the free encyclopedia - 1 views

  • Sustainable energy is the sustainable provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs.
  • Sustainable energy is the sustainable provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs.
  • Sustainable energy is the sustainable provision of energy that meets the needs of the present without compromising the ability of future generations to meet their needs. Technologies that promote sustainable energy include renewable energy sources, such as hydroelectricity, solar energy, wind energy, wave power, geothermal energy, and tidal power, and also technologies designed to improve energy efficiency.
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  • At this rate, many experts believe that solar energy is not efficient enough to be economically sustainable given the cost to produce the panels themselves.
pettitmat99

2 studies conclude that biofuels are not so green after all - The New York Times - 0 views

  • most all biofuels used today cause more greenhouse gas emissions than conventional fuels if the pollution caused by producing these "green" fuels is taken into account, two studies published Thursday have concluded.
  • The benefits of biofuels have come under increasing attack in recent months as scientists have evaluated the global environmental cost of their production. The new studies, published by the journal Science, are likely to add to the controversy.
  • When you take this into account, most of the biofuel that people are using or planning to use would probably increase greenhouse gasses substantially," sai
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  • t even that equation proved overly simplistic because the process of turning plants into fuel causes it own emissions - through refining and transport, for example
  • If vegetable oil prices go up globally, as they have because of increased demand for biofuel crops, new land is inevitably cleared as farmers in developing countries switch production. Crops from old plantations and fields go to Europe for biofuels, but new fields and plantations are created to feed people at home.
    • pettitmat99
       
      GR8 info on pollution of biofuels
  • ut the new studies suggested that when land use is taken into account few, if any biofuels, will be acceptable.
  • d: "If the whole point of biofuels directives was to reduce greenhouse gas emissions, we've found out that most biofuels are not really better than conventional fuels at that."
dpurdy

Renewable Energy, Other sources of Renewable Energy - 0 views

  • "Worldwide, approximately 3000 gigawatts (1 gigawatt = 1 GW = 1 billion watts) of energy is continuously available from the action of tides.
  • The best areas are on the eastern sides of the oceans (western side of the continents) between the 40 and 60 latitudes in both the northern and southern hemispheres.
  • While the "wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites," constructing and mooring the site and transmitting the electricity to shore would be prohibitively costly.
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  • There is a handful of wave energy demonstration plants operating worldwide, but none produces a significant amount of electricity.
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    While the "wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites," constructing and mooring the site and transmitting the electricity to shore would be prohibitively costly.
cottonetar98

Montana Environmental Information CenterCost of Wind vs. Fossil Fuels - MEIC - 0 views

  • Wind energy is cost-competitive with fossil fuels, especially coal. In Montana, wind energy is less expensive than coal for NorthWestern Energy--the state's largest utility.
  • ccording to the EIA, the total cost of wind energy without federal tax and other financial incentives is about 9.7 cents/kilowatt-hour. The total cost of conventional coal without federal tax and other financial incentives is about 9.4 cents/kilowatt-hour.
  • here are integration costs associated with intermittent renewable energy but unlike fossil fuels, wind (and solar and many other renewables) the fuel price stays the same: Zero.  Plus, wind-power technology has rapidly evolved. Turbines are much larger, growing from an average of 1.2 megawatts to 1.6 megawatts (a 33% increase in average capacity) in just three years.
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  • When comparing the cost of wind vs. fossil fuels its important to consider  fuel costs, integration costs, operating costs, and the cost of tax incentives. Wind energy is cost-competitive with fossil fuels, especially coal. In Montana, wind energy is less expensive than coal for NorthWestern Energy--the state's largest utility. The graph below from the Montana Public Service Commission, compares the costs of various resources in NorthWestern's portfolio. Judith Gap wind facility is about $47.00/Megawatt-hour (or 4.7 cents/kilowatt-hour) and Colstrip Unit 4 is $68.00/Megawatt-hour or (6.8 cents/kilowatt hour).
  • Today's typical new turbine has a 2.3-megawatt capacity; 7-megawatt turbines will be available soon.  The newer turbines can wring more electric power out of the wind (especially at lower wind speeds) than older turbines could. The combination of greater output and greater capacity nearly offsets the materials and labor cost increases plaguing traditional resources.
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    wind to fossil fuels 
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