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Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

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Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#42

Ignoring the horrible horrible horrible title ... This can only work if there is a temperature difference between the grapheme membrane and the load resistor (the lamp in the animations). Other wise, it breaks the Second Law of Thermodynamics. The problem is not that it breaks some remark from Feynman, the problem is that if there is no temperature difference, it breaks the Second Law of Thermodynamics and in particu…

Doesn’t the article explicitly say that is not the case?

> Though the thermal environment is performing work on the load resistor, the graphene and circuit are at the same temperature and heat does not flow between the two.

I’m not a physicist or even an educated layman, can you explain your comment more?

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#43
post #8
post #3

What does 'limitless' mean, physically?

If I'm understanding the article correctly, a very tiny piece of graphene can pick up a very tiny amount of energy from the random jiggles at the atomic scale. Presumably, those jiggles are always going to be there, unless somehow earth becomes a cold, dead place. So imagine the solar panel on your calculator didn't need light, just a temperature above absolute zero.

This is exactly what the press release say, but this is impossible due the the Second Law of Thermodynamics. So (select at least one)

1) The press release is wrong

2) The research article is wrong

3) The Second Law of thermodynamics is wrong.

[As a fast explanation, if the grapheme membrane and the lamp in the animation are at the same temperature, then the electrons in the lamp will get an equivalent amount of random jiggles and will counter the effect described in the article. (There may be also a similar problem with the diodes, capacitor, etc.)]

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#45
post #34

The abstract of the paper Fluctuation-induced current from freestanding graphene [1]: > At room temperature, micron-sized sheets of freestanding graphene are in constant motion, even in the presence of an applied bias voltage. We quantify the out-of-plane movement by collecting the displacement current using a nearby small-area metal electrode and present an Ito-Langevin model for the motion coupled to a circuit cont…

"However, there is power dissipated by the load resistor, and its time average is exactly equal to the power supplied by the thermal bath."

As the "thermal bath" is supplying power, this seems consistent with it being a Carnot-equivalent heat engine.

There is certainly nothing in physics that prevents the extraction of energy from an environment in which the temperature fluctuates - devices that do so to keep mechanical clocks running indefinitely have been around for some time.

http://atmosadam.com/howitworks.html

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#47

If this is representative of press releases from universities it's no wonder that people can't tell the difference between free energy scams and real physics. Sounds like nonsense to me but the article is so badly written that it's hard to tell. In fact it is hard to be sure whether they have actually created a prototype or merely simulated it.

> If this is representative of press releases from universities If you want reporting that accurately represent science, in my experience, the university press releases are even worse than the worst mainstream shit-tier media.

The incentives for the PR team is to make news. They don’t have to spend a ton of time cleaning up the mess of misleading press releases.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#48
post #18
post #6

It’s more like “limitless power from heat transferred into graphene from an external power source”. So it’s a special type of a thermo electric generator basically.

Only in the load resistor. Electron flux in the graphene membrane appears to be solely due to geometry. This curvature does not necessarily need to be buckled via heat energy. It could be mechanical or electrical, if I understand things correctly... More detail in this video clip with UArk's Paul Thibado: https://www.youtube.com/watch?v=wrleMqm3HiU I think what this research opens up is the possibility of "optimal" h…

Could they add this to waste heat pipes in power plants to extract more energy?

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#49
post #34

The abstract of the paper Fluctuation-induced current from freestanding graphene [1]: > At room temperature, micron-sized sheets of freestanding graphene are in constant motion, even in the presence of an applied bias voltage. We quantify the out-of-plane movement by collecting the displacement current using a nearby small-area metal electrode and present an Ito-Langevin model for the motion coupled to a circuit cont…

"However, there is power dissipated by the load resistor, and its time average is exactly equal to the power supplied by the thermal bath." As the "thermal bath" is supplying power, this seems consistent with it being a Carnot-equivalent heat engine. There is certainly nothing in physics that prevents the extraction of energy from an environment in which the temperature fluctuates - devices that do so to keep mechani…

The clock in your link uses the temperature fluctuations, for example if it hot during the day and cool during the night. So you can have a flux of heat from the hot part to the cold part, and extract a small part as useful energy.

If we take the press release at face value, in this device there is no difference of temperature. So if the Second Law of Thermodynamics is correct it is not possible to extract some useful energy to do something interesting, like turning on the lamp in the animation.

Re: Physicists Build Circuit That Generates Clean, Limitless Power from Graphene

#50
post #18
post #6

It’s more like “limitless power from heat transferred into graphene from an external power source”. So it’s a special type of a thermo electric generator basically.

Only in the load resistor. Electron flux in the graphene membrane appears to be solely due to geometry. This curvature does not necessarily need to be buckled via heat energy. It could be mechanical or electrical, if I understand things correctly... More detail in this video clip with UArk's Paul Thibado: https://www.youtube.com/watch?v=wrleMqm3HiU I think what this research opens up is the possibility of "optimal" h…

Yea that video is helpful and it looks like mechanical energy or thermal could be used to deform the graphene film to do some work on that film which them stores it. So it seems like what’s happening is that thermal energy is being used to put energy into the free standing graphene lattice. Then as it extends in length due to the film heating, it stores energy almost like inflating a balloon, then it touches one of the electrodes nearby and the electrons in this unique material transfer charge to the other electrode and causes the film to contract so a portion of the charge was transferred away, and it contracts then can repeat the process. So it’s a small motor that harvests either mechanical or thermal energy. But given the tiny size, it would seem like thermal might be the dominant thing since the membrane would probably need some sort of mass to benefit from random movements. Or the graphene would need to be extremely flexible. But not totally sure..
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