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Sun is the Ultimate Source of Energy

The sun is a large sphere consists full of hot gases. The source of energy at a distance of about 1.5 × 108km from the earth. The distance of the sun is 1.4 × 106km from the earth  and its mass is 2 × 1030kg. Internal part of the sun is extremely hot having temperature about 2 × 107°C. At such ultimate temperature heat is created due to various fusion reactions in which hydrogen is converted into helium nuclei.


More about sun is the ultimate source of energy


  • In the sun the large number of helium nuclei are formed per second and extremely large quantity of energy is continuously liberated by the sun in form of heat and light.
  • This power is in the outward appearance of electromagnetic radiation.
  • It is radiated in all directions in space.
  • The power available on earth from sun is 1.8 × 1011mW.
  • This power is many times more than the present consumption rate and future source energy needs of the world.
  • Thus solar energy is the only source that satisfy the present and future needs of the world.
  • This makes solar energy as one of the most ultimate source in the energies.
  The Sun



Solar Cells


  • The strategy which translate solar energy directly into electrical energy are known as solar cells or photo voltale cells.
  • Modern ultimate solar cells are made of silicon.
  • Silicon is easily available in abundance and it is environmental ultimate friendly.
  • Solar cells consists of number of thin layers of silicon.
  • Solar cell converts energy from most of radiations into electricity.
  • Typical solar cells are 2cm square piece of unpolluted silicon which produces about 0.7 watt electricity when exposed to sunlight.

About the Sun:

  • Radius  = 695000 kilo meter
  • Escape Velocity = 618.02 km/sec
  • Age of the Sun = 4.5 billion years