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

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Discussion Overview

The discussion revolves around the energy source in a setup featuring a fan or windmill inside a box, where pressure differentials are proposed to cause rotation. Participants explore the implications of this setup on thermodynamics, particularly in relation to the second law of thermodynamics and energy conversion.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant suggests that the energy for the fan's rotation comes from high-pressure air, but questions whether this process violates the second law of thermodynamics by converting high-entropy heat energy into low-entropy motion.
  • Another participant references a similar concept, the Brownian ratchet, indicating that it also fails to work as intended, although they express difficulty in explaining the reasons behind this failure.
  • A participant mentions the bobbing bird device, which operates on temperature differentials and requires water to function, noting that while it is a form of free energy, it does not produce significant power.
  • One participant humorously speculates about the potential of focusing energy from such devices into protons, suggesting a fantastical scenario involving particle acceleration and cost savings, but this is presented in a light-hearted manner.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility and implications of the energy conversion processes discussed. There is no consensus on whether the proposed setups can effectively produce usable energy or if they violate thermodynamic principles.

Contextual Notes

The discussion includes speculative ideas and humorous remarks, which may affect the seriousness of the technical claims made. The limitations of the proposed energy sources and their practical applications remain unresolved.

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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