Where Does the Energy Come From in a Box with a Fan and Windmill Setup?

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The discussion centers on a hypothetical setup involving a fan or windmill inside a box, where pressure changes cause the fan to rotate clockwise. The key point is the exploration of energy sources for this motion, with the suggestion that high-pressure air is converting high-entropy heat energy into low-entropy mechanical energy. This raises questions about the implications for the second law of thermodynamics. The conversation also references similar concepts, such as the Brownian ratchet, which attempts to harness microscopic motion but ultimately fails to produce usable energy. Additionally, there is a humorous tangent about using this energy concept in a fantastical scenario involving particle acceleration, but the main focus remains on the inefficacy of these energy-harvesting devices.
blackwizard
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A friend of mine asked me where the energy comes from in this setup:

Imagine a fan/windmill inside a box. The fan is only allowed 2 turn clockwise and is connected to an axel which exits the box.

The atmosphere will keep the air inside the box at, well, atmospheric temperateure. Every so often from random pressure changes, the pressure at 1 side of the fans blade(s) will be higher than the other. When the high pressure is on the right side of the blade it will turn the fan clockwise (its a very well lubricated fan). The result is constant, very slow, clockwise rotation.

I reckon the turning motion is getting its energy from the high pressure air but it seems like its turning useless high-entropy heat energy from the air into useful low-entropy energy in the form of turning motion. A violation of the second law?
 
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There is a similar PMM device on a microscopic scale that tries to exploit Brownian motion using nothing but a simple one-way gear and ratchet system (the kind you see in clocks). It won't work either. I wish I had the skill to explain how/why.
 
The old bobbing bird runs on the temperature differential between the ambient atmosphere and cooling due to evaporation. It's free energy. You just have to top off the glass of water now and then. There are several devices of this nature. Trouble is none of them produce any power to speak of.
 
zoobyshoe said:
Trouble is none of them produce any power to speak of.

Actually if you focused all that energy into a single proton for a whole day, you'd get a super-TeV proton. Maybe ten of them! Imagine LHC paved over and replaced with a vast army of bobbing birds, each accelerating one proton towards the detector system (powered by a pinwheel). You could save billions.
 
Rach3 said:
Actually if you focused all that energy into a single proton for a whole day, you'd get a super-TeV proton. Maybe ten of them! Imagine LHC paved over and replaced with a vast army of bobbing birds, each accelerating one proton towards the detector system (powered by a pinwheel). You could save billions.
STOP! I'm on the verge of orgasm! W will kill me if I waste it on you.
Seriously, dude... you should start a porn site based upon this.
 

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