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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."
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http://www.bis.gov.uk/assets/foresight/docs/energy/hydrogen-and-fuel-cells-towards-a-su... - 1 views

    • giumarraant99
       
      Read abstract.. why hydrogen and fuel cells
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    CO2 pollution use (sticky note)
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Solar Electricity and how it works - Photovoltaic Systems and Components, Grid-Connecte... - 0 views

  • 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
       
      Great video showing solar cell (photovoltaic) in action.
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    Solar is not always connected to grid. Sometimes there are batteries, otherwise your system is connected to grid to share excess electricity.
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BBC NEWS | Technology | Wave farms show energy potential - 1 views

  • Ocean waves carry tremendous power, and could, in theory at least, provide much of the world's electricity.
  • "What gives us tremendous hope with this technology is that our opening costs are substantially below where wind power started 20, 25 years ago."
  • Wind power has reduced its cost by 80% since, as the technology has been deployed and optimised, he says.
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  • Ms Pontes says wave energy could someday supply 20% of Portugal's power.
  • "That's equal to about six-and-a-half percent of our total capacity in the United States, equal to all the dams that we have in the US right now."
  • The European Union has proposed a commitment to generate 20% of its energy from renewable sources by the year 2020.
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Wave Energy: Pros and Cons - 0 views

  • wave power is one of the most researched areas of renewable energy.
  • Wave power results from the transport of energy by ocean surface waves and its capture into systems that can be therefore used for useful applications
  • Some of these applications include electricity generation, the pumping of water, or water desalination.
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Describe Two Different Energy Alternatives To... | Chegg.com - 1 views

  • Difference Between Alternative Energies (Ae) And Fossil Fuels essential difference between alternative energies (AE) And fossil fuels? Alternative energies will not have a lot of pollution, but fossil fuels will cause some..
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Fire Damage Restoration | SERVPRO Industries, Inc. - 0 views

  • Types of soot include: Wet Smoke Residues - Result from smoldering fires with low heat. Residues are sticky, smeary and with pungent odors.  Smoke webs can be difficult to clean. Dry Smoke Residues - Result from fast burning fires at high temperatures. Residues are often dry, powdery, small, nonsmeary smoke particles. Protein Residues - Virtually invisible residues that discolor paints and varnishes.  Extreme pungent odor. Fuel Oil Soot - Furnace puff backs distribute fuel oil soot. Other Types of Residues - Tear gas, fingerprint powder, and fire extinguisher residues also need cleanup.
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Biofuels | Biofuel Guide - 0 views

  • There have been studies that prove the many benefits of substituting fossil fuels (petroleum, etc) with biofuels such as biodiesel and ethanol. In its simplest sense, such biofuels are biodegradable which means they are derived from organic materials. They are naturally renewable. It can create numerous jobs since our own farmers can practically make them domestically. Consequently, our reliance on foreign sources of fossil fuels will be significantly reduced. Moreover, these biofuels emit nontoxic and cleaner emissions in comparison to traditional fuels. These alternative fuels also do not promote global warming, since the carbon they emit is taken back to the environment.
  • biofuel is far more simple and easy to use
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Solar vehicle - Wikipedia, the free encyclopedia - 0 views

  • Power density: Power from a solar array is limited by the size of the vehicle and area that can be exposed to sunlight. While energy can be accumulated in batteries to lower peak demand on the array and provide operation in sunless conditions, the battery adds weight and cost to the vehicle. The power limit can be mitigated by use of conventional electric cars supplied by solar (or other) power, recharging from the electrical grid.
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Home - BioFuel Information - 0 views

  • The most important advantage of using liquid as fuel is that they can be easily pumped and can also be handled easily.
  • Biofuels are the best way of reducing the emission of the greenhouse gases.
  • Some of the major producers and users of biogases are Asia, Europe and America. Theoretically, biofuel can be easily produced through any carbon source; making the photosynthetic plants the most commonly used material for production. Almost all types of materials derived from the plants are used for manufacturing biogas. One of the greatest problems that is being faced by the researchers in the field is how to covert the biomass energy into the liquid fuel
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Disadvantages of Wind Energy - Don't Get Blown Away by All The Positives of Wind - 2 views

  • 3.Wind Turbines Interfere with Television Reception.
  • Some of these blades can have a span of 100 or more feet.
  • birds easily fly into the blade path and get killed.
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  • get about a hundred of these "bad boys" cranking out a few hundred RPM's and you might have the sound of an alien attack.
  • If you do live along the coast, your personal property is rather expensive and you might not be able to afford the opportunity to afford the land, let alone a wind generator.
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Fuel Cells - Electrochemical Power - 1 views

  • One of the first applications for fuel cells based on their advantageous properties was in the US space program.
  • Compared to IC engines, fuel cells have practically no polluting exhaust like NOx and sulphides.
  • It is generally acknowledged that the feasibility and durability of fuel cells in automobiles has been proven. The major focus now is on cost reduction
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Science of Summer: How Do Ocean Waves Form? | LiveScience - 0 views

  • Presnell explained that wind speed and duration help in determining the size and frequency of ocean waves. Another factor is called "fetch," referring to the span of water over which a breeze blows, and the longer a fetch, the more energy a wave can build up.
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What are Biofuels? - 0 views

  • Biofuels are liquid fuels which have been derived from other materials such as waste plant and animal matter. There are two main types of biofuels – bioethanol and biodiesel. Bioethanol is used as a replacement for gasoline and biodiesel is used as a replacement for diesel.
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Geothermal Basics - Environment - 0 views

  • Unlike fossil fuel power plants, no smoke is emitted from geothermal power plants, because no burning takes place; only steam is emitted from geothermal facilities. Emissions of nitrous oxide, hydrogen sulfide, sulfur dioxide, particulate matter, and carbon dioxide are extremely low, especially when compared to fossil fuel emissions. The binary geothermal plant, which currently represents around 15% of all geothermal plant capacity, along with the flash/binary plant, produce nearly zero air emissions. Even dry steam plants, which are considered to have the highest levels of air emissions, are considered environmentally benign compared with fossil fuels. For example, Lake County, California, downwind of The Geysers, has met all federal and state ambient air quality standards for almost 25 years. There are 21 power plants at The Geysers, comprising a significant complex of electric generation facilities, yet even despite this, air quality is excellent. At The Geysers, air quality has even improved as a result of geothermal development because hydrogen sulfide, which would ordinarily be released naturally into the atmosphere by hot springs and fumaroles, instead now passes through an abatement system that reduces hydrogen sulfide emissions by 99.9%. (1) See also Myth #2.
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What are the advantages and disadvantages of renewable tidal power - 0 views

  • trictly, tidal power comes from the mov
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    Strictly, tidal power comes from the movement of the tides, and wave power comes from the movement of the waves. There are two kinds of tidal power stations: Tidal stream systems, which use turbines turned by the moving water to generate electricity. Very like wind power. Barrage systems. These are like dams built across rivers. After the tide comes in, the gates are closed. When the tide is low enough on the downstream side, the water flows through turbines rather like a hydro-electric dam. Wave power consists of harnessing the movement of the waves. There are various pilot schemes of this at the moment.
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How Solar Works in 4 Steps « Energy4Home - 0 views

  • 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.
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Towards a Just and Sustainable Solar Industry - Silicon Valley Toxics Coalition - 0 views

  • Although solar panels provide clean energy while in use, a variety of factors during the manufacturing and disposal of these panels have the potential to greatly damage the environment.
  • The most commonly used solar panels are silicon-based panels that share many of the same materials and manufacturing processes as semiconductors. Solar panels have the potential to create an e-waste burden if the proper infrastructure is not developed before the first wave of panels begins to come down.
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Pelamis Wave Power - 0 views

  • Since 1998, the Pelamis development programme has covered all aspects of the design from the fundamental concept refinement through to accelerated cycle testing of individual components for reliability.
  • During the first phase of Pelamis development prior to full-scale operations in 2004, extensive numerical modelling and analysis and a range of technology demonstration models at different scales were used to understand survival characteristics in extreme waves and verify the accuracy of our simulations
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How much CO2 does solar energy produce? | Ecooutfitters.net - 0 views

  • Let’s not hide the fact that manufacturing solar panels requires resources, fossil fuels that release CO2 emissions and add to our carbon footprint. However, it’s been shown in numerous studies that solar panel production releases nowhere near as much CO2 and other greenhouse gases as electric generated from coal, oil, natural gas, etc. (and you still need to produce the equipment to generate electricity from those sources as well.)
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