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The Disadvantages of Wave Energy | eHow.com - 0 views

  • Because waves are erratic, the amount of energy a wave generator can produce is unpredictable and, therefore, cannot be used as a sole reliable energy source.
  • accidental hydraulic fluid leaks can cause a major environmental problem.
  • A collision could cause a hydraulic spill or leak and become an environmental hazard.
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  • Boats not able to see the generators could cause a potential collision hazard and pose problems for the safety of both those on board and to the wave energy generator.
  • Wave energy boasts many advantages such as its low cost, zero to no pollution, and a large energy output.
  • Wave energy generators can cause noise pollution and be a nuisance to those living close to them, according to the UK Department for Business Innovation & Skills. The noise emanating from a generator, though, is often covered up by the noise of the waves.
  • Wave energy generators can cause noise pollution and be a nuisance to those living close to them, according to the UK Department for Business Innovation & Skills. The noise emanating from a generator, though, is often covered up by the noise of the waves. Wave power generators can also be unsightly to some.
  • Wave energy generators can cause noise pollution and be a nuisance to those living close to them, according to the UK Department for Business Innovation & Skills. The noise emanating from a generator, though, is often covered up by the noise of the waves. Wave power generators can also be unsightly to some.
  • Wave energy generators can cause noise pollution and be a nuisance to those living close to them, according to the UK Department for Business Innovation & Skills. The noise emanating from a generator, though, is often covered up by the noise of the waves. Wave power generators can also be unsightly to some. Floating devices are large snake-like machines floating parallel to one another throughout an area close to the seashore. Some may find them offensive or unpleasant.
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    wave cost is low
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HowStuffWorks "How Fuel Cells Work" - 1 views

  • The fuel cell will compete with many other energy­ conversion devices, including the gas turbine in your city's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.
  • Sir William Grove invented the first fuel cell in 1839. Grove knew that water could be split into hydrogen and oxygen by sending an electric current through it (a process called electrolysis). He hypothesized that by reversing the procedure you could produce electricity and water. He created a primitive fuel cell and called it a gas voltaic battery. After experimenting with his new invention, Grove proved his hypothesis. Fifty years later, scientists Ludwig Mond and Charles Langer coined the term fuel cell while attempting to build a practical model to produce electricity.
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    " Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently."
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How Hydrogen Fuels Cells Work - 0 views

  • The hydrogen fuel cell operates similar to a battery. It has two electrodes, an anode and a cathode, separated by a membrane. Oxygen passes over one electrode and hydrogen over the other. The hydrogen reacts to a catalyst on the electrode anode that converts the hydrogen gas into negatively charged electrons (e-) and positively charged ions (H+).
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    The hydrogen fuel cell operates similar to a battery. It has two electrodes, an anode and a cathode, separated by a membrane. Oxygen passes over one electrode and hydrogen over the other. The hydrogen reacts to a catalyst on the electrode anode that converts the hydrogen gas into negatively charged electrons (e-) and positively charged ions (H+).
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Hydrogen Basics - Fuel Cells - 1 views

  • A fuel cell converts the chemical energy in hydrogen and oxygen into direct current electrical energy by electrochemical reactions. Fuel cells are devices that convert hydrogen gas directly into low-voltage, direct current electricity. The cell has no moving parts.
  • The process is essentially the reverse of the electrolytic method of splitting water into hydrogen and oxygen. In the fuel cell, the cathode terminal is positively charged and the anode terminal is negatively charged. These electrodes are separated by a membrane. Hydrogen gas is converted into electrons and protons (positive hydrogen ions) at the anode. The protons pass through the membrane to the cathode, leaving behind negatively charged electrons. This creates a flow of direct current electricity between the terminals when connected with an external circuit. This current can power an electric motor placed in this circuit. The hydrogen ions, electrons, and oxygen combine at the cathode to form water, the only byproduct of the process.
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    " 13kW PEM fuel cell (Photo: Ballard Power Systems, Inc.) The process is essentially the reverse of the electrolytic method of splitting water into hydrogen and oxygen. In the fuel cell, the cathode terminal is positively charged and the anode terminal is negatively charged. These electrodes are separated by a membrane. Hydrogen gas is converted into electrons and protons (positive hydrogen ions) at the anode. The protons pass through the membrane to the cathode, leaving behind negatively charged electrons. This creates a flow of direct current electricity between the terminals when connected with an external circuit. This current can power an electric motor placed in this circuit. The hydrogen ions, electrons, and oxygen combine at the cathode to form water, the only byproduct of the process"
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EIA Energy Kids - Hydrogen - 2 views

  • Like electricity, hydrogen is a secondary source of energy. It stores and carries energy produced from other resources (fossil fuels, water, and biomass).
  • ydrogen is the simplest element. Each atom of hydrogen has only one proton. It is also the most plentiful gas in the universe. Stars like the sun are made primarily of hydrogen. The sun is basically a giant ball of hydrogen and helium gases. In the sun's core, hydrogen atoms combine to form helium atoms. This process — called fusion — gives off radiant energy.
  • Hydrogen gas is so much lighter than air that it rises fast and is quickly ejected from the atmosphere. This is why hydrogen as a gas (H2) is not found by itself on Earth. It is found only in compound form with other elements. Hydrogen combined with oxygen, is water (H2O). Hydrogen combined with carbon forms different compounds, including methane (CH4), coal, and petroleum.
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  • Hydrogen has the highest energy content of any common fuel by weight
  • Like electricity, hydrogen is an energy carrier and must be produced from another substance. Hydrogen is not currently widely used, but it has potential as an energy carrier in the future. Hydrogen can be produced from a variety of resources (water, fossil fuels, or biomass) and is a byproduct of other chemical processes.
  • Steam reforming is currently the least expensive method of producing hydrogen and accounts for about 95% of the hydrogen produced in the United States. This method is used in industries to separate hydrogen atoms from carbon atoms in methane (CH4). But the steam reforming process results in greenhouse gas emissions that are linked with global warming.1
  • Electrolysis Creates No Emissions but Is Costly Electrolysis is a process that splits hydrogen from water. It results in no emissions, but it is currently an expensive process. New technologies are currently being developed.
  • Hydrogen fuel cells make electricity. They are very efficient, but expensive to build. Small fuel cells can power electric cars. Large fuel cells can provide electricity in remote places with no power lines.
  • Portable fuel cells are being sold to provide longer power for laptop computers, cell phones, and military applications.
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    tells all about hydrogen
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EIA Energy Kids - Solar - 2 views

  • 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
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  • 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.
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Biomass Energy Home Page Biomass Energy: Cost of Production - 0 views

  • The cost of producing ethanol varies with the cost of the feedstock used and the scale of production. Approximately 85 percent of ethanol production capacity in the United States relies on corn feedstock. The cost of producing ethanol from corn is estimated to be about $1.10 per gallon.
  • Because a gallon of ethanol contains less energy than a gallon of gasoline, the production cost of ethanol must be multiplied by a factor of 1.5 to make an energy-cost comparison with gasoline. This means that if ethanol costs $1.10 per gallon to produce, then the effective cost per gallon to equal the energy contained in a gallon of gasoline is $1.65. In contrast, the current wholesale price of gasoline is about 90 cents per gallon.
  • A major hurdle facing commercial biodiesel production is the cost of producing the fuel. Vegetable oil seed procurement, transport, storage and oil extraction accounts for at least 75 percent of the cost of producing biodiesel. The cost varies depending on the feedstock used. For example, based on the market price for industrial rapeseed grown in Washington and Idaho, the estimated cost of producing biodiesel is $2.56 per gallon of rapeseed methyl ester. Recent estimates put the cost of production in the range of $1.30 per gallon (using waste grease feedstock) to $2.00 or more per gallon using soybean oil.
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Hydropower: Generate Energy with Rivers and Ocean Tides - For Dummies - 0 views

  • When water flows toward the shore with the incoming tide, it flows through a tidal energy system, turning a turbine that generates electricity. When the tide shifts and flows in the opposite direction, away from shore, the tidal energy system again captures the energy with a turbine and converts it into electricity.
  • An important source of alternative energy is hydropower: converting the flow of rivers and ocean waves and tides into electricity through dams and turbines. The best part about both of these water sources is that they’re 100 percent renewable.
  • The main advantage of using ocean tides for energy is that tides and waves are a constant, unchanging, clean source of energy. The main disadvantage is that tidal energy systems may impact the environment by changing the flow of water into shoreline and estuarine ecosystems.
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Business Opportunities Assessment for Solar Photovoltaic (PV) Market in Brazil - 0 views

  • The Brazilian government still awaits a reduction in solar prices to create a specific auction by the end of 2013 or the beginning of 2014. However, the Ministry of Mines and Energy (MME) does not demonstrate any signs of this happening.
  • In 2013, however, revenue and capacity installed are expected to double: projects will be delivered, the resolution 482/2012 will have a major impact, and X% of the National Association of Electric Energy’s (ANEEL’s) research and development (R&D) will conclude. Capacity installed expectations in 2013 will near X megawatts (MW); in 2014, X MW; in 2015, X MW; and beyond, faster expansion is expected. Currently, capacity installed for the solar market is X MW, but it is expected to reach X MW by 2017. The total possible capacity installed for Brazil is close to X gigawatts (GW). This market revenue will have a X% compound annual growth rate (CAGR) during the forecast period (2012–2017) due to ANEEL´s R&D, international events, and the resolution 482/2012 cost reductions. Now, market revenue is close to $X million and can reach $X million by 2017.
  • Distributed generation could grow faster with financial support, better service from energy concessionaries, and cost reductions; nonetheless, it will grow considerably.
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  • Distributed microgeneration: electricity generating system, with capacity installed less than or equal to
  • kilowatts (kW); uses solar energy connected to the distribution network through facilities of consumer units Distributed minigeneration: electricity generating system with a capacity installed greater than 100 kW and less than or equal to X MW for the same sources; connected to the distribution network through facilities of consumer units
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What is Tidal Energy? | Renewable Green Energy Power - 0 views

  • It was used in the watermills along the shores of England during the Roman age and also used along the shores of France and Spain. This period was around 900 AD. The water rising from the tides was impounded in barrages and it was allowed to flow through waterwheels and other energy capturing devices thus capturing the energy and converting it into useful work used to grind grains and produce flour. The first tidal mill in the US was built in Salem, MA in 1635.
  • In recent history it was not until the 1960s that a tidal energy plant was built in France, on the estuary of La Rance, to capture the tidal energy and produce electricity. The plant has been operating for the past 50 or so years producing electricity without missing a tide. The second tidal energy plant was built about 20 years later in 1982 in Nova Scotia, Canada.
  • Water is much denser than air and this means that the tidal energy turbines would be much smaller than the wind energy turbines needed for the production of the same amount of electricity.
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  • produced by the rise and fall of tides which occur in all parts of the world.
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Electricity from Geothermal Energy - 1 views

  • The heat from the earth's own molten core can be converted into electricity. This core consists primarily of extremely high temperature liquid rock known as magma. This "geothermal" heat circulates within the rock or is transferred to underground reservoirs of water, which also circulate under the earth's crust. Because of the near limitless ability of the earth to produce magma, and the continuous transfer of heat between subsurface rock and water, geothermal energy is considered a renewable resource.
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    "The heat from the earth's own molten core can be converted into electricity. This core consists primarily of extremely high temperature liquid rock known as magma. This "geothermal" heat circulates within the rock or is transferred to underground reservoirs of water, which also circulate under the earth's crust. Because of the near limitless ability of the earth to produce magma, and the continuous transfer of heat between subsurface rock and water, geothermal energy is considered a renewable resource. Geothermal resources have been harnessed as an energy source since the dawn of civilization, when natural hot springs were first used for cooking and bathing. The geothermal resources tapped to generate electricity are far more intense than those used for space heating and can reside as deep as 10,000 feet below the earth's surface. Capital costs for the construction of geothermal power plants are much higher than for large coal-fired plants or new natural gas turbine technologies. But geothermal plants have reasonable operation and maintenance costs and no fuel costs. Though more expensive than wind power in most cases, new geothermal electricity generation facilities are increasingly competitive with fossil options."
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How Much Does Solar Energy Cost? | Solar Energy Facts - 1 views

  • Which State do you live in?
  • Federal solar tax rebate
  • most of the cost of your system has to do with where you live.
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  • These can be tax write-offs or money back in your pocket.
  • Many states, like New Jersey and Massachusetts, have developed credit markets. You get credits for producing solar and you can sell them for money.
  • if you can cut your power bill before you go solar, everything will cost less. Consider a home energy audit before upgrading to solar energy.
  • Local utilities and municipalities (LA is a great example) have their own solar energy subsidies
  • How much Solar Energy do you Want to Produce?
  • Sometimes just knocking off a part of the bill can give you huge monthly electricity cost savings, as in the case of tiered electricity rates
  • In some areas your utility will pay you for an extra electricity you send back to the grid.
  • importance of energy efficiency
  • If you buy the system you’ll see big up-front costs
  • so you might not get to claim all the credits and rebates available.
  • Generally this option trades long-term financial gain for low (or no) up-front cost.
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    How much the cost is and the importance of the place you are changing the cost and refund/credits you will ether gain or lose
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How is geothermal energy better than fossil fuels - 1 views

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    "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."
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Biofuel Guide - Introduction to Ethanol and Biodiesel - 0 views

  • First generation biofuel are those fuel derived from vegetable or animal fats/oils, starch or sugar with the use of modern technology.
    • dpurdy
       
      Gallons per acre In the perspective of land use and agricultural efficiency, ethanol seems to be a good choice. The reason is that about 420 gallons of ethanol can be generated per acre in contrast to 60 gallons of biodiesel per acre soybeans. Consequently, the cost of soybean oil would significantly increase if biodiesel production is increased as well.
  • 1. Let the base organic material (corn, sugarcane, wheat, etc) pass through a grinding meal to pulverize the selected material. 2. Then, liquefy it by placing the blend of water, grain powder and an enzyme that facilitates the breakdown of the grain compound into a high-heat cooker. 3. Cool it afterwards. Add another enzyme that will facilitate the conversion of starch into sugars which are then fermented, producing alcohol from the cooled mash. 4. Start the fermentation by adding yeast to the sugar mixture. The sugars will be broken down to ethanol (a form of alcohol) and carbon dioxide. 5. Distill the fermented mixture in order for the ethanol to separate from the solids. 6. Get rid of the water from the separated ethanol through a dehydration process.
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    "Cellulose ethanol production is newly discovered experimental processes which can breakdown cellulose in woody fibers. This would only mean that through this method, ethanol from crop wastes, trees and grasses can be derived. It is significantly better since trees and grasses require small amount of energy in comparison to grains that must be replanted annually. "
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Wind Power: clean, sustainable, and affordable | Union of Concerned Scientists - 0 views

  • Wind power generates electricity with... No air emissions No fuel to mine, transport, or store No cooling water No water pollution No wastes
  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas. A typical (750 kW) wind turbine provides enough power for 328 typical (non-electric heating) homes.
  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas. A typical (750 kW) wind turbine provides enough power for 328 typical (non-electric heating) homes.
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  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas. A typical (750 kW) wind turbine provides enough power for 328 typical (non-electric heating) homes.
  • No fuel to mine, transport, or store
  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas.
  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas.
  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas
  • Wind power can reduce pollution generated by fossil fuels such as coal, oil, and gas
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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.
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Alternative Fuels Data Center: Biodiesel Production and Distribution - 0 views

    • pettitmat99
       
      great photo on the production of biodeisels
  • he production process converts oils and fats into chemicals called long-chain mono alkyl esters, or biodiesel. These chemicals are also referred to as fatty acid methyl esters, and t
  • Biodiesel is produced from vegetable oils, yellow grease, and tallow.
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  • Raw or refined plant oil, or recycled greases that have not been processed into biodiesel, are not biodiesel and should be avoided
  • Fats and oils (triglycerides) are much more viscous than biodiesel, and low-level vegetable oil blends can cause long-term engine deposits, ring sticking, lube-oil gelling, and other maintenance problems that can reduce engine life
  • Biodiesel is distributed from the point of production to retail fueling stations by truck, train, or barge.
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    good website to find most information on biofuels
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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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Tidal power (tidal energy) facts - Interesting energy facts - 1 views

  • Tide mills, in use on the Spanish, French and British coasts, date back to 787 A.D.
  • Tidal energy is a type of energy that produces electricity and other forms of power through the use of water.
  • The tide moves a huge amount of water twice each day and although the tidal energy supply is reliable and plentiful, converting it into useful electrical power is not easy.
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  • The first involves converting the power of the horizontal movement of the water into electricity. The second involves producing energy from the rise and drop of water levels
  • Although the technology required to harness tidal energy is well established, tidal power is expensive, and there is only one major tidal generating station in operation. This is a 240 megawatt station at the mouth of the La Rance river estuary in France.
  • There are three prototypes of tidal energy devices: horizontal axis turbine, vertical axis turbine, and oscillating devices
  • Tidal energy is not on the list of sustainable energy technologies the UN agencies even though for islanders it is our best hope for large amounts of affordable clean power.
  • Turbines, similar to wind turbines, can be anchored to the sea bed to generate electricity from tidal currents
  • Tidal energy has an efficiency of 80% in converting the potential energy of the water into electricity
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A Basic Overview of Fuel Cell Technology - 0 views

  •   Fuel Cell Basics Through this website we are seeking historical materials relating to fuel cells. We have constructed the site to gather information from people already familiar with the technology–people such as inventors, researchers, manufacturers, electricians, and marketers. This Basics section presents a general overview of fuel cells for casual visitors. What is a fuel cell? How do fuel cells work? Why can’t I go out and buy a fuel cell? Different types of fuel cells.     What is a fuel cell? A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes.
  • in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now “ionized,” and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
  • Oxygen enters the fuel cell at the cathode and, in some cell types (like the one illustrated above), it there combines with electrons returning from the electrical circuit and hydrogen ions that have traveled through the electrolyte from the anode. In other cell types the oxygen picks up electrons and then travels through the electrolyte to the anode, where it combines with hydrogen ions.
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