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Produce energy from air

  1. Jul 1, 2013 #1
    Sun shining on earth and make it warm but its not warm enough to make energy of it
    What happend to air molkols when it getting hot?
    Why we can concentrate light by miror whitout spend energy but we cant do it on air? We need power to compres air to make it warmer and we can use it to produce energy
    I say if we can change the propertice of hot molkol to less hots , energy will concetrate and transfered to nighber molkols
    Do you think its posible?
    Sorry for my bad english
     
  2. jcsd
  3. Jul 1, 2013 #2

    mfb

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    molkols? Do you mean molecules?
    In hot air, those molecules are moving faster.

    Solar thermal energy and solar updraft towers (just prototypes) exist.

    Air is not light. The molecules in hot air have a random motion, while sunlight comes from one direction only.
     
  4. Jul 1, 2013 #3
    I dont mean lighting energy i asking to transmite random motion energy to other moulkoles of air
    Yes im new on english language sorry about that
     
  5. Jul 1, 2013 #4

    mfb

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    That is not possible in an "ordered" way, as the motion is completely unordered.
     
  6. Jul 17, 2013 #5
    I think what you mentioned is referred as a classic example against the second law of thermodynamics.
     
  7. Jul 19, 2013 #6
    No i say use sun energy from air temperture
     
  8. Jul 20, 2013 #7

    mfb

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    As jiayue9 and me explained, this is not possible.
    You would need some colder material nearby to extract useful energy.
     
  9. Jul 20, 2013 #8
    Like mfb said there is a way of extracting energy directly from heat but it requires a difference in temperatures between two sides. It is called the Thermoelectric effect you can read it on wikipedia.

    www.wikipedia.com/wiki/Thermoelectricity
     
  10. Jul 24, 2013 #9
    This is all about my poor english language
    I know we can not use this low temp of air for produce energy
    I know if we try to compres air it use more energy than it produce
    I say sun did not spend energy to mix with air so maybe we can take shining energy out, without using energy.
    Can we ?
     
  11. Jul 24, 2013 #10

    mfb

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    What is "shining energy"?
    Solar cells use the solar radiation to extract energy.
    If you do not want to use that, you have to heat something to a higher temperature (above the temperature of the environment). Sunlight can do this, and I linked two concepts which use that.
     
  12. Jul 24, 2013 #11
    Sunshine have energy right? It come from sun right? When it crash to earth make it warm right? And it make air warm, yes? I try to find other way (not direct from sunshine) to use this energy i asking to explore energy from air mulecols
     
  13. Jul 24, 2013 #12

    mfb

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    Right.

    All those methods were mentioned here.
     
  14. Jul 24, 2013 #13
    You speak abut ways that exist i looking to find new way
     
  15. Jul 24, 2013 #14

    mfb

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    Right, and I told you that there cannot be a completely new way. The laws of physics do not allow that.
     
  16. Jul 24, 2013 #15
    I say sunshine did not spend energy to mix with air so maybe we can take shining energy out, without using energy.
    Can we ?
     
  17. Jul 24, 2013 #16

    mfb

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    If you don't build anything special, hot air mixes with the remaining air.
    There is no "shining energy".
    No.
     
  18. Jul 24, 2013 #17
    Shining energy is translate from my language it mean heat that transfer by light
     
  19. Jul 25, 2013 #18

    mfb

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    Thermal radiation?
    Okay, that does not change my points.
     
  20. Jul 25, 2013 #19

    russ_watters

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    If these answers were here just for the asking, don't you think the techniques would have already be used?
     
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