solar energy


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solar energy

  1. 1. Hello
  2. 2. 5.Advantage and disadvantage 1. Define the sun CONTENT 4.Renewable and Non Renewable energy 2. Solar Energy 3.photovoltaic's
  3. 3. 5.Advantage and disadvantage 1. Define the sun CONTENT 4.Renewable and Non Renewable energy 3.photovoltaic's 2. Solar Energy
  4. 4. The sun yellow dwarf star in the center of the solar system diameter = 1,392,000 km, 109 times of earth’s mass = 2×1030kg, 330,000 times of earth’s 99.86% of the solar system’s total mass ¾ hydrogen, the rest is mostly helium primary source of energy in the earth
  5. 5. CONTENT
  6. 6. solar energy the earth receives 174 petawatts [1015 watts] from the sun 30% is reflected into space and the rest is absorbed by land, oceans, clouds etc. the total energy absorbed by earth’s atmosphere, oceans, land mass is 3,850,000 exajoules [1018 joules] per year energy entering the earth from the sun is twice the energy harnessed from all non-renewable sources of energy combined
  7. 7. CONTENT
  8. 8. photovoltaic's generating electrical power by converting solar radiation into dc electricity using semiconductors that exhibit the photovoltaic effect The photovoltaic effect is the creation of voltage or electric current in a material upon exposure to light first observed by Alexandre-Edmond Becquerel in 1839
  9. 9. the photovoltaic cell also called solar cell, is an electrical device that converts the energy of light directly into electricity by the photovoltaic effect made of monocrystalline silicon or polycrystalline silicon or amorphous silicon or cadmium telluride, or copper indium selenide/sulfide first built by Charles Fritts in1883 by coating the semiconductor selenium with an extremely thin layer of gold
  10. 10. the photovoltaic cell cont. photons in sunlight hit the solar panel and are absorbed by semiconducting materials, such as silicon electrons are knocked loose from their atoms, and current starts flowing through the material and this electricity is captured an array of solar cells converts solar energy into a usable amount of direct current [DC] electricity
  11. 11. CONTENT
  12. 12. Difference between renewable energy and non-renewable energy Renewable energies are the energies that never run out, they don't pollute our planet and some of them produce a lot of energy. Examples: wind energy, solar energy... And non-renewable energies, are the energies that in a day they run out, and they pollute a lot our planet.
  13. 13. Why we need to use renewable energy? Many forms of energy that we have grown dependent on are from non-renewable energy sources. This means that when the energy has been consumed, the supply has gone and cannot be replaced. An example of this is coal. Coal is known as a fossil fuel and is the largest source of energy for the generation of electricity worldwide. When coal has been mined and burnt, it cannot be replaced. Finding alternative energy sources, ideally from renewable sources, will decrease our dependency on fossil fuels and other non-renewable energy sources.
  14. 14. CONTENT
  15. 15. advantages solar energy is a renewable source of energy in the presence of solar power, use of non-renewable sources of energy like petroleum can be lessened which also lessens pollution an array of solar cells converts solar energy into a usable amount of direct current [DC] electricity Though solar panels are expensive, the total amount that would be saved makes the price of the panels will seem small
  16. 16. disadvantages solar panels are expensive solar power is inefficient in cloudy areas batteries and solar panels occupy more space ( Need more spaces ) solar power maintenance is a problem disposal is difficult for the batteries and solar panels when they have broken down because they contain toxic chemicals like lead, sulfuric acid & cadmium telluride
  17. 17. solar energy trends
  18. 18. solar energy trends
  19. 19. solar energy trends