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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

#11

Post by vitus »

> In the 1950s, physicist Léon Brillouin published a landmark paper refuting the idea that adding a single diode, a one-way electrical gate, to a circuit is the solution to harvesting energy from Brownian motion. Knowing this, Thibado’s group built their circuit with two diodes for converting AC into a direct current (DC).

So, they built a full-wave rectifier (albeit with only 2 instead of, say, 4 diodes)? Pretty neat to see electrical engineering fundamentals at work.

(also, for any who wanted specifics: article is at https://journals.aps.org/pre/abstract/10.1103/PhysRevE.102.0... ; abstract contains a couple of circuit diagrams)

edit: updated link, thanks for pointing that out

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

#12

Post by [deleted] »

cowpig wrote: post #8
Jugurtha wrote: 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.

[deleted]

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

#14

Post by jl2718 »

aduitsis wrote: post #5

Naive question, wouldn't this (converting Brownian motion into electricity) violate the 2nd law of thermodynamics? (edit, this is explicitly addressed further in the article: That's an important distinction, said Thibado, because a temperature difference between the graphene and circuit, in a circuit producing power, would contradict the second law of thermodynamics. "This means that the second law of thermodynamics…

This sounds like a mangled explanation. It seems to me, somewhat naively, that the resonator must be held at a higher temperature than the rest of the circuit to produce work on the load.

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

#15

Post by kwhitefoot »

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.

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

#16

Post by tgsovlerkhgsel »

kwhitefoot wrote: post #15

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.

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

#18

Post by ArtWomb »

xt00 wrote: 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" harvesting. There is some resonant frequency, some circuit configuration yet to be discovered that is perhaps self-sustaining. They've chosen "stochastic thermodynamical" circuits because its low hanging fruit. But it seems really exciting to me. Almost like a third class of energy production after solar and hydrogen (where 99% of research funds are allocated). Ocean wave energy harvesting perhaps?

In any case, congrats to the researchers on their painstaking hard work ;)

Fluctuation-induced current from freestanding graphene: toward nanoscale energy harvesting

https://arxiv.org/abs/2002.09947

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

#19

Post by IgorPartola »

ArtWomb wrote: post #18
xt00 wrote: 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…

This does sound promising. Is it possible to run this process in reverse a la a heat pump to create an AC with no moving parts? Or is this purely a one way process?

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

#20

Post by tsimionescu »

> The idea of harvesting energy from graphene is controversial because it refutes physicist Richard Feynman’s well-known assertion that the thermal motion of atoms, known as Brownian motion, cannot do work. Thibado’s team found that at room temperature the thermal motion of graphene does in fact induce an alternating current (AC) in a circuit, an achievement thought to be impossible.

So it sounds like, if this really works, it may have some impact on our general understanding of thermodynamics or the properties of Brownian motion?

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