• Learning How to Convert Heat Directly Into Power: A Thermoelectric Materials Emulator
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[url]http://www.sciencedaily.com/releases/2013/10/131024143313.htm[/url] [IMG]http://images.sciencedaily.com/2013/10/131024143313.jpg[/IMG] [QUOTE][B]Discovered in the 19th century, thermoelectric materials have the remarkable property that heating them creates a small electrical current. But enhancing this current to a level compatible with the needs of modern technologies has revealed an extraordinary challenge for scientists of the last decades, despite important theoretical and experimental efforts. Now a novel approach could lead to substantial progress. At ETH Zurich the quantum optics group of Tilman Esslinger has created a key model to better understand the fundamental phenomena -- "a thermoelectric material emulator."[/B] It happened almost by chance: In Zurich group member Jean-Philippe Brantut and his colleagues had just set up a new experiment when visiting professor Antoine Georges from the Collège de France and University of Geneva had a look at the laboratory and was thrilled. "We didn't really think that in our experiment we could have efficient thermoelectricity," remembers Jean-Philippe Brantut, "but then he told us, that our setup was extremely interesting, something he and his colleagues Corinna Kollath (University of Bonn) and Charles Grenier (Ecole Polytechnique -- CNRS) had been looking for for years." Antoine Georges returned the very next day with a bunch of equations to convince the researchers that their experiment was an ideal way to study thermoelectricity. This triggered a fruitful collaboration between theorists in Paris, Bonn and Geneva and experimentalists in Zurich. The results of the international team are now presented in "Science." [B]From heat to electricity[/B] The generation of electricity from heat usually involves burning a combustible, which then heats a fluid that brings a mechanical turbine into motion, which eventually produces an electrical current. In thermoelectric materials, the entire cycle that is performed by a heat engine occurs naturally. However, this effect is weak and for the materials known so far, the efficiency of thermoelectric generators is much smaller than that of electrical power plants. At the moment the technology is mainly used for powering space probes like rover Curiosity exploring planet Mars or for small devices like self-powered sensors. But experts expect a wide range of possible applications in the future. In any engine there is a lot of heat wasted. Car companies are already testing different systems to recover energy from the exhaust gas expecting fuel savings of 3 to 5 %. Other consumer applications could be powering mobile phones or watches by body heat. A highly efficient thermoelectric material would be a major source of renewable energy, since heat is usually wasted by human activities. At ETH the thermoelectric material emulator sits in a vacuum chamber made out of glass. Enclosed is a gas of Lithium atoms. Using lasers the gas is cooled down to very low temperatures close to absolute zero below minus 273 degree Celsius. Under these conditions the atoms in the gas behave like the electrons in a material. To simulate thermoelectricity the atoms are trapped by a set of laser beams. These create a spatially varying structure in which the atoms move like electrons in a material. [B]A big surprise[/B] Using atoms trapped by lasers to simulate the behavior of complex materials is a well-tested method in Zurich. For the last ten years the ETH quantum optics group has studied superconductors or magnets, and even devices attached to leads and conducting currents. But the researcher didn't expect their new experiment to be such a big success. "With simple ingredients we simulate thermoelectricity that is as high in efficiency as in natural materials," explains Tilman Esslinger, Professor for Quantum Optics. "That was a big surprise." Although it is still basic research the experiment may have a stronger impact on materials science than the team thought at the beginning. "Our experiment could serve as a kind of benchmark," says Jean-Philippe Brantut who will continue with his research founded by the Swiss National Science Foundation. In the next two years the team will try to bring the original experiment forward in order to study more complex systems. But already now the cold atom emulation shines a new light on thermoelectricity: comparison between theory and experiments, which are often hard for natural materials due to their high complexity, can now be precisely performed on the atoms. Even the effects of defects and disorder in materials have been successfully explored with the cold atom emulator.[/QUOTE]
This could be extremely useful for future unmanned space missions, since thermoelectric generators are used to power some spacecraft and probes. (curiosity for example)
Does this mean in the future when they get small enough I could power my PC with the heat from my CPU?
[QUOTE=Stents*;42644570]Does this mean in the future when they get small enough I could power my PC with the heat from my CPU?[/QUOTE] That's only slightly paradoxical :v:
Would this make it possible to make solar farms that beam power back to Earth? or no, i suppose the atmosphere would dissipate too much of the energy to make it cost/energy effective.
couldn't this be used in nuclear reactors?
With all the power we could receive from raging hard-ons, the government should give tax credit for buying porn.
I don't know a lot about the physics of energy, but what has always confused me is that everyone says heat can't be turned back into other forms of energy (if I'm understanding correctly), and yet anything that has any amount of heat past absolute zero emits electromagnetic energy (that's why red-hot things glow and why the human body lights up with infra-red vision). Could someone more knowledgeable explain to me what I've gotten wrong?
So from what I've garnered from the article, confining Li atoms to a fixed 3D position while heating them is essentially vibrating a fixed particle. The vibrations (Phonons) create a current by pushing electrons around with the overall charge of the Li atoms.
[QUOTE=GoldenDargon;42644541]This could be extremely useful for future unmanned space missions, since thermoelectric generators are used to power some spacecraft and probes. (curiosity for example)[/QUOTE] Even better it would help increase the efficiency of current power plants hopefully reducing the rate of fossil fuel burning.
[QUOTE=SIRIUS;42644862]couldn't this be used in nuclear reactors?[/QUOTE] I hope so It really seems silly when you consider that a nuclear power station is literally just a steam turbine with radioactive stuff heating some water below it
[QUOTE=Zeke129;42645555]I hope so It really seems silly when you consider that a nuclear power station is literally just a steam turbine with radioactive stuff heating some water below it[/QUOTE] Imagine how much energy must be wasted.
[QUOTE=Helix Snake;42645376]I don't know a lot about the physics of energy, but what has always confused me is that everyone says heat can't be turned back into other forms of energy (if I'm understanding correctly), and yet anything that has any amount of heat past absolute zero emits electromagnetic energy (that's why red-hot things glow and why the human body lights up with infra-red vision). Could someone more knowledgeable explain to me what I've gotten wrong?[/QUOTE] heat can be transformed into other types of energy in a bunch of ways - directly into electrical through the thermoelectric effect or more indirectly through a steam turbine (like in most power stations) what people usually mean is ambient heat cannot be transformed into energy because you need a difference in temperature to actually get energy out of it
[QUOTE=Helix Snake;42645376]I don't know a lot about the physics of energy, but what has always confused me is that everyone says heat can't be turned back into other forms of energy (if I'm understanding correctly), and yet anything that has any amount of heat past absolute zero emits electromagnetic energy (that's why red-hot things glow and why the human body lights up with infra-red vision). Could someone more knowledgeable explain to me what I've gotten wrong?[/QUOTE] It's not that you can't convert heat to electricity, it's that we have no useful way of doing so.
[QUOTE=Eltro102;42645607]what people usually mean is ambient heat cannot be transformed into energy because you need a difference in temperature to actually get energy out of it[/QUOTE] That's exactly what I'm referring to though, doesn't something with ambient heat emit electromagnetic energy regardless?
[QUOTE=Helix Snake;42645629]That's exactly what I'm referring to though, doesn't something with ambient heat emit electromagnetic energy regardless?[/QUOTE] as blackbody radiation, sure a small amount in theory we could harvest that (and that's how those infrared cameras work) but we wouldn't get any meaningful work out of it because of the small amount radiated and the inefficient methods we have to catch it
[QUOTE=Reshy;42645592]Imagine how much energy must be wasted.[/QUOTE] Quite alot actually: [URL="http://www.youtube.com/watch?v=uK367T7h6ZY"]http://www.youtube.com/watch?v=uK367T7h6ZY[/URL] Some current gen reactors use some of this waste heat for desalinating water.
[QUOTE=Reshy;42645592]Imagine how much energy must be wasted.[/QUOTE] Don't we waste energy by using resistors in our electronics?
[QUOTE=Grabigel;42648087]Don't we waste energy by using resistors in our electronics?[/QUOTE] Its miniscule typically, however cumulative.
[QUOTE=LoneWolf_Recon;42648046]Quite alot actually: [URL="http://www.youtube.com/watch?v=uK367T7h6ZY"]http://www.youtube.com/watch?v=uK367T7h6ZY[/URL] Some current gen reactors use some of this waste heat for desalinating water.[/QUOTE] Damn.
I bet it still won't play ColecoVision ROMs without choking.
No more inefficient steam turbines!....hopefully.
[QUOTE=Grabigel;42648087]Don't we waste energy by using resistors in our electronics?[/QUOTE] In well designed electronics? Yes, but barely. Don't forget, resistors are a fundamental part of any circuit. They don't just burn energy, they have a purpose.
[QUOTE=SIRIUS;42644862]couldn't this be used in nuclear reactors?[/QUOTE]Nuclear power? Use it for Coal power.
[QUOTE=Rapist;42644596]That's only slightly paradoxical :v:[/QUOTE] It's also perpetual.
[QUOTE=RoboChimp;42650738]Nuclear power? Use it for Coal power.[/QUOTE] why, nuclear is much cleaner than coal and can produce much more energy
[QUOTE=Ninja Gnome;42651947]why, nuclear is much cleaner than coal and can produce much more energy[/QUOTE]Yeah, nuclear waste is really clean and there is absolutely no danger or risk at all. We don't even have nuclear power on our grid in Australia so applying it to dangerous nuclear reactors wouldn't do anything for us over here.
So does this mean we can make internal combustion engines more efficient? Imagine using the [URL="https://en.wikipedia.org/wiki/Internal_combustion_engine#Energy_efficiency"]energy wasted as heat[/URL] to spin a [URL="https://en.wikipedia.org/wiki/Flywheel_energy_storage#Motor_sports"]flywheel generator[/URL] that dumps the electrical energy into hub mounted electric motors on-demand. For silent city driving or wicked fast acceleration boost.
[QUOTE=RoboChimp;42652115]Yeah, nuclear waste is really clean and there is absolutely no danger or risk at all. We don't even have nuclear power on our grid in Australia so applying it to dangerous nuclear reactors wouldn't do anything for us over here.[/QUOTE] Comparatively? More people have died from coal power than have died from nuclear power. In just the US, about 30 people a year die directly from coal mining, and this isn't even taking the amount of pollution generated by coal into effect. Really, the pollution generated by coal power is way more of a killer than the nuclear waste will really ever be. Also, nuclear reactors, when properly maintained, are not that dangerous at all. The main incidents you might be thinking of (Fukushima, Chernobyl) were under [I]very[/I] irregular conditions.
[QUOTE=Ninja Gnome;42652347]Comparatively? More people have died from coal power than have died from nuclear power. In just the US, about 30 people a year die directly from coal mining, and this isn't even taking the amount of pollution generated by coal into effect. Really, the pollution generated by coal power is way more of a killer than the nuclear waste will really ever be. Also, nuclear reactors, when properly maintained, are not that dangerous at all. The main incidents you might be thinking of (Fukushima, Chernobyl) were under [I]very[/I] irregular conditions.[/QUOTE]Interesting point but I'm thinking of the risk involved with handling radioactive materials. Also what do they do with nuclear waste? And given the nature of the people of this country I wouldn't trust anyone here to run a nuclear plant anyway. So if thermoelectric materials were used for nuclear power, we'd miss out completely.
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