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Fuel Cell Markets - Advantages & Benefits of Fuel Cell & Hydrogen Technologies - 2 views

  • Advantages by Application Telecoms CHP Fuel Cell Generators Electric Vehicles - APU's and Range Extenders Fuel Cell Forklifts Marine Power Portable Power
  • Low Emissions – Using hydrogen, PEM fuel cells only emit water at the point of use. Even when using hydrocarbon fuels, fuel cells emit considerably less emissions than other combustion based technologies, this is for two reasons. Firstly their higher efficiency means they require less fuel to generate the same energy and secondly because there is no combustion, there are negligible NOx or SOx emissions and no particulate emissions.
  • Reliability & Maintenance – The only moving parts in fuel cells are involved with water, heat and air management (pumps, blowers, compressors). When compared to internal combustion engines, there are considerably less moving parts and these require less maintenance (no oil changes every 150 hours). Less maintenance means less site visits or trips to the garage and reduced operating costs. Fuel cells can be monitored remotely and any problems dealt with quickly.
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  • Few moving parts means all you will ever hear of a fuel cell is either a compressor, blower or pump
  • Hydrogen is the lightest of all gases and disperses very quickly, it is also non-polluting and hazardous to the surrounding environment (unlike gasoline a spillage / leak will not cause an environmental disaster). Hydrogen, like natural gas and petrol, is a fuel and will burn when ignited. Hydrogen is only explosive when it is able to build up in a enclosed space, which is very difficult as it has a habit of escaping (hydrogen is the smallest of all elements). As long as appropriate safety procedures are followed, as they should with any fuel, hydrogen is a safe fuel.
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    Advantages & Benefits of Hydrogen and Fuel Cell Technologies High Efficiency - Like generators and other engines, fuel cells are energy conversion devices - they convert stored energy within a fuel into usable energy. A fuel cell uses an electrochemical reaction to extract energy directly in the form of heat and electricity, both of which can be utilised at the point of generation.
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Wave power - Wikipedia, the free encyclopedia - 2 views

  • Waves are generated by wind passing over the surface of the sea. As long as the waves propagate slower than the wind speed just above the waves, there is an energy transfer from the wind to the waves.
  • The first known patent to utilize energy from ocean waves dates back to 1799 and was filed in Paris by Girard and his son.[12] An early application of wave power was a device constructed around 1910 by Bochaux-Praceique to light and power his house at Royan, near Bordeaux in France
  • Once the wave energy is captured at a wave source, power must be carried to the point of use or to a connection to the electrical grid by transmission power cables.[2
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  • The realistically usable worldwide resource has been estimated to be greater than 2 TW.[49][50] Locations with the most potential for wave power include the western seaboard of Europe, the northern coast of the UK, and the Pacific coastlines of North and South America, Southern Africa, Australia, and New Zealand. The north and south temperate zones have the best sites for capturing wave power. The prevailing westerlies in these zones blow strongest in winter. Waves are very predictable; waves that are caused by winds can be predicted five days in advance.[citation needed]
  • There is a potential impact on the marine environment. Noise pollution, for example, could have negative impact if not monitored, although the noise and visible impact of each design varies greatly.[5]. Other biophysical impacts (flora and fauna, sediment regimes and water column structure and flows) of scaling up the technology is being studied.[51] In terms of socio-economic challenges, wave farms can result in the displacement of commercial and recreational fishermen from productive fishing grounds, can change the pattern of beach sand nourishment, and may represent hazards to safe navigation.[52] Waves generate about 2,700 gigawatts of power
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Energy Resources: Tidal power - 1 views

  • Advantages Once you've built it, tidal power is free. It produces no greenhouse gases or other waste. It needs no fuel. It produces electricity reliably. Not expensive to maintain. Tides are totally predictable. Offshore turbines and vertical-axis turbines are not ruinously expensive to build and do not have a large environmental impact. Disadvantages A barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed. Fish can't migrate, unless "fish ladders" are installed. Only provides power for around 10 hours each day, when the tide is actually moving in or out. There are few suitable sites for tidal barrages Is it renewable? Tidal energy is renewable. The tides will continue to ebb and flow, and the energy is there for the taking.
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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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What is wave energy? | Pelamis Wave Power - 4 views

  • What is wave energy? Waves are generated by the passage of wind across the surface of the sea.  Energy is transferred from the wind to the waves.  Waves travel vast distances across the ocean and at great speed and the energy is concentrated near the water surface.  The energy within a wave is proportional to the square of the wave height.  Therefore a two-meter high wave has four times the power of a one-meter high wave. The longer and stronger the wind blows over the surface of the sea, the higher, longer, faster and more powerful the sea is.
  • Although wave energy is a form of concentrated wind energy, as it has often travelled over large distances it is regularly out of phase with the local wind conditions.  Wave energy can therefore help to balance output variability from other renewable sources and maximise the efficient use of the electricity networks.   Wave energy is also more predictable than many other forms of renewable energy, such as wind or solar, and can be forecast accurately up to five days in advance.
  • Wave energy is clean and renewable!  It is one of the last renewable energy forms which mankind has yet to harness, and its potential is huge.
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  • Wave energy could play a major part in the world’s efforts to combat climate change, potentially displacing 1 – 2 billion tonnes of CO2 per annum from conventional fossil fuel generating sources.
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Tidal Energy | Pros for Wave and Tidal Power - 3 views

  • Tidal energy is one of the oldest forms of energy used by humans. Indeed, tide mills, in use on the Spanish, French and British coasts, date back to 787 A.D.. Tide mills consisted of a storage pond, filled by the incoming (flood) tide through a sluice and emptied during the outgoing (ebb) tide through a water wheel. The tides turned waterwheels, producing mechanical power to mill grain. We even have one remaining in New York- which worked well into the 20th century.
  • Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
  • A tidal range of at least 7 m is required for economical operation and for sufficient head of water for the turbines
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  • Currently, 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 (1 megawatt = 1 MW = 1 million watts) at the mouth of the La Rance river estuary on the northern coast of France
  • Tidal electricity can be used to displace electricity which would otherwise be generated by fossil fuel (coal, oil, natural gas) fired power plants, thus reducing emissions of greenhouse and acid gasses.
  • There is a high capital cost for a tidal energy project, with possibly a 10-year construction period.
  • Electricity can be generated by water flowing both into and out of a bay. As there are two high and two low tides each day, electrical generation from tidal power plants is characterized by periods of maximum generation every twelve hours, with no electricity generation at the six hour mark in between.
  • Tidal energy is a renewable source of electricity which does not result in the emission of gases responsible for global warming or acid rain associated with fossil fuel generated electricity. Use of tidal energy could also decrease the need for nuclear power, with its associated radiation risks. Changing tidal flows by damming a bay or estuary could, however, result in negative impacts on aquatic and shoreline ecosystems, as well as navigation and recreation.
  • Indeed, tide mills, in use on the Spanish, French and British coasts,
  • date back to 787 A.D..
  • Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
  • idal energy is one of the oldest forms of energy used by humans. Indeed, tide mills, in use on the Spanish, French and British coasts, date back to 787 A.D.. Tide mills consisted of a storage pond, filled by the incoming (flood) tide through a sluice and emptied during the outgoing (ebb) tide through a water wheel. The tides turned waterwheels, producing mechanical power to mill grain. We even have one remaining in New York- which worked well into the 20th century. Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
  • Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable.
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    "Tidal power is non-polluting, reliable and predictable.Tidal barrages, undersea tidal turbines - like wind turbines but driven by the sea - and a variety of machines harnessing undersea currents are under development. Unlike wind and waves, tidal currents are entirely predictable."
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    when it started to be used and who it was used by.
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Geothermal Education Office - Geothermal Energy - 2 views

  • Like many renewable resources, geothermal resources need relatively high initial investments to access the heat, hot water and steam. But the geothermal "fuel" cost is predictable and stable. Fossil fuel supplies will increase in cost as reserves are exhausted. Fossil fuel supplies can be interrupted political disputes abroad. Renewable geothermal energy is a better long term investment.
  • Examples are the huge costs of global climate change; the health effects from ground level pollution of the air; future effects of pollution of water and land; military expenditures to protect petroleum sources and supply routes; and costs of safely storing radioactive waste for generations. Geothermal energy can already compete with the direct costs of conventional fuels in some locations and is a clean, indigenous, renewable resource without hidden external costs.
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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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Tides of the Ocean - Windows to the Universe - 0 views

  • Each day the ocean surface rises and falls because of tides. The highest point of the rise is called high tide. The lowest point is called low tide. Most places have two high tides and two low tides each day. Tides happen because of the gravitational pull of the Moon and Sun on ocean water. The Moon has a much greater impact on tides than the Sun because it is much closer. The Moon pulls water that is closest to it making a high tide on the side of the Earth closest to the Moon and there is a high tide on the opposite side of the Earth too. Low tides happen in places between the high tides. Because Earth is rotating, the tides change over time. The difference between high tide and low tide is called the tidal range. The tidal range can be as little as a few centimeters to as much as several meters depending on the shape of the ocean floor. In Canada's Bay of Fundy the tidal range is very large – 16 meters.
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Geothermal Energy | A Student's Guide to Global Climate Change | US EPA - 0 views

  • Geothermal power plants, which use heat from deep inside the Earth to generate steam to make electricity. Geothermal heat pumps, which tap into heat close to the Earth's surface to heat water or provide heat for buildings.
  • At a geothermal power plant, wells are drilled 1 or 2 miles deep into the Earth to pump steam or hot water to the surface.
  • hot springs, geysers, or volcanic activity, because these are places where the Earth is particularly hot just below the surface.
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  • Hot water is pumped from deep underground through a well under high pressure. When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam. The steam spins a turbine, which is connected to a generator that produces electricity. The steam cools off in a cooling tower and condenses back to water. The cooled water is pumped back into the Earth to begin the process again.
  • Geothermal heat pumps can do all sorts of things—from heating and cooling homes to warming swimming pools.
  • heat by pumping water or a refrigerant (a special type of fluid) through pipes just below the Earth's surface, where the temperature is a constant 50 to 60°F.
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Switch to Clean Energy | A Student's Guide to Global Climate Change | US EPA - 1 views

  • When we get electricity from renewable energy sources like wind and solar power, we avoid the carbon dioxide emissions that would have come from burning fossil fuels like coal, oil, or natural gas.
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Voith | Wave power plants - 0 views

  • With this technology, sea water turbines do not come into contact with water
  • Instead, a column of air is set in motion which drives the machines. In detail, this works in the following manner: The waves spill into a hollow container which is open to the sea. This compresses and calms the air column in a so-called collector in a similar way to how an air pump works. The power plant "breathes" in and out. The pressure difference is then turned into rotary energy in a so-called Wells turbine (named after its inventor). This is in turn passed to a generator where electricity is produced. This means that the turbine has the air periodically flow through it from both sides, depending on whether the device is "breathing" in or out. Because of the special rotor geometry, there is no need to either periodically change the blade angles or the direction of rotation. If you consider the fact that an average of some 3 million waves break on to the coast every year, it is clear that only this simple turbine design can offer maximum reliability.
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Advantages and Disadvantages Of Wave Energy - 0 views

  • Wave energy is as source of power that comes from the endless march of the waves as they roll into the shore then back out again. Humans harness this power along the coastal regions of the United States, Canada, Scotland, and Australia. Energy that comes from the waves in the ocean sounds like a boundless, harmless supply.
  • Advantages of Wave Energy 1. Renewable: The best thing about wave energy is that it will never run out. There will always be waves crashing upon the shores of nations, near the populated coastal regions. The waves flow back from the shore, but they always return. Unlike fossil fuels, which are running out, in some places in the world, just as quickly as people can discover them. Unlike ethanol, a corn product, waves are not limited by a season. They require no input from man to make their power, and they can always be counted on
  • Also unlike fossil fuels, creating power from waves creates no harmful byproducts such as gas, waste, and pollution. The energy from waves can be taken directly into electricity-producing machinery and used to power generators and power plants nearby. In today’s energy-powered world, a source of clean energy is hard to come by.
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  • Another benefit to using this energy is its nearness to places that can use it. Lots of big cities and harbors are next to the ocean and can harness the power of the waves for their use. Coastal cities tend to be well-populated, so lots of people can get use from wave energy plants.
  • A final benefit is that there are a variety of ways to gather it. Current gathering methods range from installed power plant with hydro turbines to seafaring vessels equipped with massive structures that are laid into the sea to gather the wave energy.
  • The biggest advantages of wave power as against most of the other alternative energy sources is that it is easily predictable and can be used to calculate the amount that it can produce. The wave energy is consistent and proves much better than other sources which are dependent on wind or sun exposure.
  • The biggest disadvantage to getting your energy from the waves is location. Only power plants and towns near the ocean will benefit directly from it. Because of its source, wave energy is not a viable power source for everyone. Landlocked nations and cities far from the sea have to find alternate sources of power, so wave energy is not the clean energy solution for everyone.
  • As clean as wave energy is, it still creates hazards for some of the creatures near it. Large machines have to be put near and in the water to gather energy from the waves. These machines disturb the seafloor, change the habitat of near-shore creatures (like crabs and starfish) and create noise that disturbs the sea life around them. There is also a danger of toxic chemicals that are used on wave energy platforms spilling and polluting the water near them.
  • Another downside is that it disturbs commercial and private vessels. Power plants that gather wave energy have to be placed by the coastline to do their job, and they have to be near cities and other populated areas to be of much use to anybody. But these are places that are major thoroughfares for cargo ships, cruise ships, recreational vehicles and beach goers. All of these people and vessels will be disrupted by the installation of a wave energy gathering source. This means that government officials and private companies that want to invest in wave energy sources have to take into account and consider the needs of those they may be disturbing.
  • Wind power is highly dependent on wavelength i.e. wave speed, wave length, wavelength and water density. They require a consistent flow of powerful waves to generate significant amount of wave power. Some areas experience unreliable wave behavior and it becomes unpredictable to forecast accurate wave power and therefore cannot be trusted as reliable energy source.
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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

Wind Energy - 1 views

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fossil fuels BP - 0 views

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