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Heat Transfer for Hot Attic?

  1. Jun 28, 2012 #1
    Hello,

    My attic gets blazing hot in the summer days, i have installed more than enough electric fans, my house just never gets shaded and the attic is quite small.

    my first idea was to build a giant shade producing robot.

    after that, I decided to vent all of my A/C air into the attic.

    after the heat stroke, i decided it was time to figure out a clever and tricksy method of heat transfer.

    basically i want to transfer the heat into a robot that then turns that heat into direct current, whereupon I run my microwave and toaster off of the stored energy. I just don't know how.

    i am rich and highly educated. your quadratic equations and stuff won't be abstruse for me.
     
  2. jcsd
  3. Jun 28, 2012 #2

    russ_watters

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    Welcome to PF!

    Quadratic equations may not escape you, but the second law of thermodynamics does. You cannot convert heat to electrical energy without a sink for the heat to go to.

    Why don't you just install fans in your attic to ventilate it with outside air? Sending your air conditioned air into the attic won't cool your house it will heat it, since your house will have to replace that air with hot outside air.
     
  4. Jun 28, 2012 #3
    that sink for the heat to go to, that is the robot. bam.

    how do you like that? Now how do I build it?

    I installed two electric fans. i did not actually pump my a/c air into the attic.

    two fans do not help, so i have an abundance of heat at my disposal. I need to either transfer it elsewhere, or use it.

    you know this
     
  5. Jun 28, 2012 #4

    DaveC426913

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    Not sure you realize what a heat sink is. Or a robot. :wink:


    Anyway, the issue here is not to try to actively cool the attic but to let it cool itself. I'll bet dollars to donuts you do not have ventilated soffits in your eaves. What you want is an airflow that enters underneath your eaves troughs and flows up the inside of the peaked roof in your attic, and out the top. Without it, all the fans in the world will do you little good.
    VentsRoof.jpg

    This is the problem with my attic. It too gets hot as blazes, and the reason is because when the attic was finished they did not allow enough soffit ventilation.
     
  6. Jun 29, 2012 #5

    russ_watters

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    Fix your attitude, please.

    A device that is doing the conversion cannot act as its own sink.

    Consider a peltier device, which converts heat to electricity. One side is heated and the other side must be cooled, creating a gradient across which heat flows. The larger the gradient, the greater the heat flow and the greater the energy that can be extracted. Similar to a hydroelectric dam.
     
  7. Jun 29, 2012 #6
    So you need some openings down low and others up high so as to create natural flow of air. warm air rises and as it does will pull in cooler outside air from below. And of course you should insulate the ceiling in the attic...There are standards for setting such ventilation areas.

    Like Dave, I had to add soffit ventilation area as well as additional high roof vents. My problem was that on cold winter days when the sun would rise I had condensation on the underside of my roof.
     
  8. Jun 29, 2012 #7
    i actually have enough soffit ventilation given the 1/150 rule, which is better than the 1/300 rule for attic ventilation. I also have two 1500cfm fans that run during the day.

    its much better than before, but i didn't come to the physics forum to get lectured about attic ventilation, whereas i am a ventilation master.

    they actually call me Dr. Venty around where i live.


    as for you russ, you need to tell me how to build this robot that is a peltier gradient nano sink. i needs to be a heat exchanger too. ok? hurry up.
     
  9. Jun 29, 2012 #8
    maybe i'm not being clear...

    i dont need to cool down my attic, i'm stating that I have an abundant heat supply and would like to transfer it and would like the "physics experts" to help me quantify the culpability of the diameter of ideas.
     
  10. Jun 29, 2012 #9
  11. Jun 29, 2012 #10
  12. Jun 29, 2012 #11

    DaveC426913

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    This, coming from the guy who strung this together?
    :smile:
     
  13. Jun 29, 2012 #12
    i think that just demonstrates the level of understanding and magnanimosity i have achieved.

    but lets break out some science to help you along with my robot

    using the Euler-Riemann zeta function we can deduce that Bose-Einstein Condensate would be proportional to the ratio of pie. So, what if I had a net robot that would capture the suns electromagnetic rays and turn use an ion exchange, making them cool?

    or create a force field around my house that uses condensation to cool the inner area?
     
  14. Jun 29, 2012 #13
    How about using the heat to warm water??

    No robot needed!
     
  15. Jun 29, 2012 #14
    I suppose you could put a vent with an electric turbine on your roof. As the hot air rises out of the attic the air will leave this vent and turn a turbine that will produce (probably a pathetic amount) of electricity.

    PS: Are you stoned right now?
     
  16. Jun 29, 2012 #15

    micromass

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    The OP is refusing to listen, the thread is thus locked.
     
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