Speaking of energy, I found this report from the University of Arkansas by Bob Whitby fascinating:
A team of University of Arkansas physicists has successfully developed a circuit capable of capturing graphene’s thermal motion and converting it into an electrical current.
“An energy-harvesting circuit based on graphene could be incorporated into a chip to provide clean, limitless, low-voltage power for small devices or sensors,†said Paul Thibado, professor of physics and lead researcher in the discovery.
The findings, published in the journal Physical Review E, are proof of a theory the physicists developed at the U of A three years ago that freestanding graphene — a single layer of carbon atoms — ripples and buckles in a way that holds promise for energy harvesting.
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.
There’s generally quite a gap between doing something in a lab and making it commercially available so I don’t think you should expect your EV to be powered by Brownian motion any time soon. I would expect that the first practical applications would be in certain kinds of sensors or, to get wild and crazy, wearable electronics or LED light bulbs that last practically forever.
I expect Feynman is right, and Thibado et al. have made a mistake.
IMO that’s where the smart money would be but you never can tell.
Sounds low energy application, even if viable. What did Feynman say about the effects of eliminating Brownian motion as energy was siphoned off, and how long could it power anything until practically or theoretically depleted? Has anyone seen those calculations?
Perhaps Feynman aside. For those here familiar with thermo, the first law is just a way of saying conservation of energy. It goes here; it goes there. It is not destroyed. The second law is just a way of saying what direction a process will go: always more entropy (randomness)
So in the case at hand, reduced Brownian motion (or graphene jiggling) and would drive less randomness (more order in the Brownian moving C atoms) and importantly, thereby make available energy. That would manifest in lower graphene temperature.
I quickly looked up the cited article. They are proposing an overturned second law. (ie Feynman was wrong) Entropy could go both ways. (they could reload the energy source, energy free) WTF. Seems like gobbldygook. Setting aside entropy issues and Gibbs Free Energy (it runs the world, people), what the hell is replacing the used energy??
The only things that can replace utilized energy in a system are previously stored energy: particularly potential and chemical……….until exhausted. And the big one: mass to energy. What the hell, graphene bombs?
I’m not a good enough exotic math guy to follow any equation based arguments. But I do sure know I don’t believe in perpetual motion machines, free lunches….
I have a though experiment.
Is it theoretically possible for a material to exist that has properties allowing it to serve as a “heat diodeâ€. A container made of such a material would be able to harvest energy from the surrounding environment which could then of course be used to generate electricity.
It would not violate the second law, but could it exist?
Grey
You are on to something, but let me help you.
In the summer, with the sun beating down, is your car hot when you get into it? Of course it is. It absorbs radiative (sun) and ambient diffusion (the air is hot outside) heat.
For centuries people have used the heat capacity of materials to store it, and then release it. Heat rocks or metals in a fire; put them inside the tent to dissipate the heat through the night. This is wholly different from the graphine thing.
In the issue at hand, the proposition was that energy manifested as Brownian motion in graphine could be harnessed and used, reducing the motion (reduced entropy and energy) and never depleting the energy. Cool. That only defies both the first and second laws of thermodynamics…………..but who’s counting?
At first I though Dave was pulling our leg. Then I looked at the article. As I said, I couldn’t follow the math, but I’m dubious. And if they are onto something, write a paper and collect you Nobel Prize……
I had something a little more impossible in mind.
Analogies to a box made of one way mirror, working not just for radiant energy, but for ambient temperature differences.
Somebody will buy it.
Bake bread with no cord!