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charlesjos00

Definition of a Solar Cell - History of Solar Cells - 0 views

  • A solar cell is any device that directly converts the energy in light into electrical energy through the process of photovoltaics. The development of solar cell technology begins with the 1839 research of French physicist Antoine-César Becquerel. Becquerel observed the photovoltaic effect while experimenting with a solid electrode in an electrolyte solution when he saw a voltage develope when light fell upon the electrode.
crandallmad00

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.
wooddan99

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.
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.
wooddan99

Geothermal Could be Cheaper than Fossil Fuels with $3 Billion DOE Investment Says NYU S... - 0 views

  • Geothermal could be cheaper than fossil fuels, according to a study just published at NYU Stern. Yet, strangely, geothermal received the fewest Federal DOE dollars invested in R&D over the last 8 years
sokolkyl00

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.
geczyluk99

What is a Fuel Cell - 0 views

  • Because they don’t go through the combustion process, there’s none of the pollution that’s associated with pollution, there’s no nox, there’s no particulate formation.
bishophan00

It is said that rotation of the earth causes wind.But how? - 0 views

  • Wind speed and direction is a result of high and low pressure areas in the atmosphere.
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    Wind speed and direction is a result of high and low pressure areas in the atmosphere.
sokolkyl00

Getting to Solar Energy Sustainability | The Energy Collective - 2 views

  • I recognize this may seem like fantasy, but if the proponents of solar energy and other clean energy alternatives really want it to succeed they must get off life support, be free from the addiction to unsustainable subsidies, and given a chance to grow and thrive on their own in a healthy, competitive market environment where innovation and hard work create sustainable market equilibrium.
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.
geczyluk99

Benefits and Challenges - 0 views

  • Fuel cell systems are not yet as durable as internal combustion engines, especially in some temperature and humidity ranges.
  • FCVs are currently more expensive than conventional vehicles and hybrids. Manufacturers must bring down production costs, especially the costs of the fuel cell stack and hydrogen storage, to compete with conventional technologies.
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    "FCVs are currently more expensive than conventional vehicles and hybrids. Manufacturers must bring down production costs, especially the costs of the fuel cell stack and hydrogen storage, to compete with conventional technologies."
westkea00

Pelamis Wave Power - 0 views

shared by westkea00 on 25 Sep 13 - Cached
westkea00

Pelamis Wave Power - 0 views

  • The Pelamis is an offshore wave energy converter that uses the motion of waves to generate electricity.
  • The machine operates in water depths greater than 50m and is typically installed 2-10km from the coast. The machine is rated at 750kW with a target capacity factor of 25-40 per cent, depending on the conditions at the chosen project site. On average one machine will provide sufficient power to meet the annual electricity demand of approximately 500 homes.
  • The Pelamis machine is made up of five tube sections linked by universal joints which allow flexing in two directions. The machine floats semi-submerged on the surface of the water and inherently faces into the direction of the waves. As waves pass down the length of the machine and the sections bend in the water, the movement is converted into electricity via hydraulic power take-off systems housed inside each joint of the machine tubes, and power is transmitted to shore using standard subsea cables and equipment.
westkea00

Wave Power - Energy from ocean surface waves - 1 views

  • Wave energy is produced when electricity generators are placed on the surface of the ocean
  • Energy output is determined by wave height, wave speed, wavelength, and water density.
  • The energy provided is most often used in desalination plants, power plants and water pumps.
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  • The energy provided is most often used in desalination plants, power plants and water pumps.
  • Just like wind mills and wind turbines that generate power and electricity from the wind, scientists are now working to generate power from the sea
  • Wave energy is among the impressive list of renewable energy resources that is being developed in the United States.
  • Ocean wave energy can be captured directly from surface waves. Blowing wind and pressure fluctuations below the surface are the main reasons for causing waves.
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    Controlling factor of electric power.
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