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New Material Breaks World Record Turning Heat into Electricity
- marius_k 7y agoCould this also be used to reverse electricity into cold-heat gradient with high efficiency?
- cperciva 7y agoYes, the thermoelectric effect works both ways.
- Dylan16807 7y agoIf you have a very small cooling job, yes. Anything above a handful of thermal watts is still better off using a compressor.
- ttul 7y agoUntil now... maybe.
- hinkley 7y agoWe were talking just the other day about back-side power distribution in ICs. Basically you bury the power rails really deep, lap the chip down to half a micrometer, and add through vias to ge to the rails. So now you’ve got a very thin chip and all the power comes in on the side with pretty much nothing else on it. I wonder if you mount the chip backside up, put these little peltier devices on the hot spots, if you can maintain a higher heat transfer rate.
- Dylan16807 7y agoThe thing is, a chip generally cools just fine with heat pipes and fins up to 200 or more watts. And the built-in heat spreader gets rid of hot spots very effectively. At that power level a peltier tends to be worse than useless, even if you're putting enormous amounts of power through it. Even if you double the efficiency it's still a bad option.
- forgotmypwd123 7y agoOverclocked threadrippers can hit 500W[1]. I can see peltiers and 'vapochill' style phase-change cooling making a comeback... 1. https://www.anandtech.com/show/13124/the-amd-threadripper-2990wx-and-2950x-review/13 https://www.anandtech.com/show/13124/the-amd-threadripper-29...
- hinkley 7y agoI think I accept the argument that in a desktop with a giant cooler attached to the CPU, this may not improve things or make them worse. But there are an awful lot of mobile processors with passive cooling or complex heat pipes, and it would take more convincing that such a scheme would also fail there. I'm also wondering if it might be useful for 'race to idle' situations by extending the time until thermal throttling kicks in.
- Dylan16807 7y agoPhase change yes. Or water chillers. I can't imagine why anyone would be more inclined to use a peltier as wattage increases. Higher wattages make that idea progressively worse unless you have some very specific and strange requirements.
- hinkley 7y agoAre you talking about the giant Peltiers that flopped in the late 90's and early 00's? Nobody is talking about that. I'm talking about micron, maybe millimeter-scale peltiers to increase the thermal conductivity of the absolute worst spots on the chip. That may mean a particular ALU, or it could mean circuits with far more layers than we can manage now (due to yields and thermal limitations)
- Dylan16807 7y ago> the absolute worst spots on the chip. That may mean a particular ALU The worst spots aren't much worse than the median spots (over calculating silicon, not cache). Anything big enough to be a hot spot, like a big ALU, is big enough to represent a large portion of your power budget. The main goal is to get all the heat away from the chip, and putting peltiers on a large portion of the chip gives you more heat to take away. For anything significantly smaller than that, the heat bleeds out without the need of a peltier. There might be a middle ground where peltiers could make a real life difference, but I'm skeptical. > or it could mean circuits with far more layers than we can manage now That sounds like you're cooling the entire chip, which is the worst time to use a peltier.
- icegreentea2 7y agoYes, the thermal-electric effect is reversible. It's sometimes called the Peltier effect (or thermal-electric cooling) when used in heat pumping mode, and Seebeck effect when used in electricity generation (thermal-electric generation).
- data-wrangler 7y agoThis would be an even bigger deal for remote spacecraft that rely on the heat from on-board nuclear reactors.
- wcoenen 7y agoI think you are thinking about an RTG instead of an actual reactor.
- RL_Quine 7y agoSome space craft have actually had full reactors on them believe it or not.
- nickpinkston 7y agoChecks out - I didn't realize we actually did fission... in... spaaaaace! https://en.wikipedia.org/wiki/Nuclear_power_in_space#Fission_systems https://en.wikipedia.org/wiki/Nuclear_power_in_space#Fission...
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- wcoenen 7y agoThere were indeed real nuclear reactors with thermoelectrics being launched in the cold war. However, thermoelectrics have an efficiency well below 10% (maybe a bit better with this improvement but not much). For that reason, future reactors in space will likely use Stirling engines instead.
- mechhacker 7y agoCorrect. Space stirling designs* (and tested engines) have been much more performant than the RTG designs *I spent part of my career working on these devices and saw many of them running in labs
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- jcims 7y agoEvery time some phenomenon arises from a recipe of fairly typical materials I wonder what other surprises nature has in store for us. The idea that the crystalline structure plays a large role in the bulk thermal conductivity of the material is kind of mind-blowing at first and then retrospectively obvious.
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- abdullahkhalids 7y agoThe space of "fairly typical materials" is very wide because there are lots of elements and their combinations blow up very fast. Secondly, materials are often very sensitive to small physical or chemical changes, resulting in wildly differing properties. To you the simpleness of the final result is surprising, but that simple result was discovered after a long and exhaustive search. A search into a wide and shallow space can be just as impressive and difficult as a search into a narrow and deep space.
- darkteflon 7y agoI think OP was just expressing delight and wonder at our surprising and elegant universe rather than making light of the findings.
- jcims 7y agoIt goes even beyond the combinations, no? The physical manifestation of the end material plays a key role in its properties, so you could just make a simple alloy of the above and not have this thermoelectric effect. Only when you apply them just so do you get this outcome. So crazy...
- s_Hogg 7y agoWhat does the level of performance indicated here likely mean in terms of the efficiency of, say, a thermal energy plant of some description? How far is the needle shifted for an end user?
- RL_Quine 7y agoThe Peltier and Seebeck effects are so grossly inefficient that even an order of magnitude increase in efficiency doesn’t bring it into reason for basically any purpose. I’m not actually aware of any device ever made that uses the seebeck effect in any substantial way other than the little heat powered fans people put on wood stoves. The peltier effect is just down right awesome, you put power in and now it’s cold!? Reality steps in at some point when you need to drive down the efficiency even further to get large differentials and ugh. They’re insane to deal with, any amount of thermal load worth speaking of means you have to use a phase change system. It is very handy for camera sensors though and other scientific gear. There’s a world world of CCD sensors that act in a vacuum with peltier devices driving them below -30c to reduce the noise produced by the sensor.
- Baeocystin 7y agoMy camp cooler is powered by a 60W peltier. Plugs in to any automotive cigarette lighter. It will keep things refrigerator cold for as long as you want, and it's almost completely silent in operation. There's tons of different models on the market. FWIW.
- londons_explore 7y agoYou realise how inefficient they are when you load it full of warm beer and run it for a few days and the beer isn't even cool yet. From that 60 watts of input power, you only get ~4 watts of cooling, and with some leaking through the walls of the box, the time to cool down something of substantial mass can be weeks. That's why you have to use a real fridge to do the work before starting the journey. And at that point, those electric fridges are only slightly more useful than a pile of ice packs.
- RandomWorker 7y agoSadly the key here is lab scale and vanadium. Costs won’t make it worthwhile.
- mmazing 7y agoEasy, just build a fusion reactor capable of eventually producing vanadium from hydrogen, and you got yourself a stew going! Edit : Method of producing said reactor left as an exercise for the reader.
- deleted 7y ago[deleted]
- rohan1024 7y agoI don't think the research is intended for large scale electricity production. It's for small sensors and processors and that won't cost much. This opens up a quiet a few possibilities like buy a temperature sensor place it somewhere and it starts feeding data into your home WiFi. No wires, no batteries.
- DaniFong 7y agoCommercial vanadium metal, of about 95% purity, costs about $20/lb. This is a tiny layer, so even at the 99.9% purity level cost of $100/oz, materials cost is not likely be a critical factor. The main constraint is that it's not making much power -- at this level it's really for very low power applications, especially things like sensors and comms.
- anovikov 7y agoVanadium is only $6 per pound. About as expensive as street price of ice cream. It's not a rare earth element or anything like that.
- ganzuul 7y agoLots of hand tools like hex-head wrenches also use it. Typically they get stamped with "CR-V" for chromium-vanadium. It's basically all you need to know when buying standard quality hand tools. In addition to being affordable the material is available in bulk and there exists an industry which knows how to work with it. Same with all the materials mentioned.
- kart23 7y agoCIA is already all over this
- sunseb 7y agoWould this be efficient in a mobile phone?
- Jon_Lowtek 7y agoThis will be slowly but surely be used everywhere. Reducing heat output while providing electricity is almost always a win-win situation.
- comicjk 7y agoThere are a lot of factors you're not considering. Reducing heat output is good, yes, but putting a layer between your chips and their heat sink is bad! Even though the total heat output is lower, the chip temperature will be higher, because it will be more insulated. There is no way around this; any heat-to-power device acts as insulation compared to a plain heat conductor. You will also have added weight and cost. In a phone, where the heat differences are small, the electricity gained will be almost nothing. So actually we're not likely to see this in phones.
- gus_massa 7y agoThis adds weight and volume that are bad for a mobile phone. Also, the size must be enough to process all the heat from the phone. In systems with a big heatsink you will need a bigger device between the heat source and the heatsink. This will not be a problem for phones, but it may be a problem for notebooks. Also, with a difference of 30C (60F) they increased the maximum efficiency from 1% to 4%, but that temperature difference is probably too hot for a phone in your pocket. It's probably better to have a smaller phone, or to use the additional space/weight in a bigger battery.
- icris 7y agodoes this imply an overall entropy reduction for a whole system comprising a device and support apparatus for reusing its heat as energy source supply?
- 0xBA5ED 7y agoNo you can't make a perpetual motion machine with it ;)
- Zenst 7y agoBut could you produce a cooling system that this could power? Or at least recycle some of the heat fridge/freezers produce back into electricity.
- icris 7y agoi am aware of it. i was not pretending we could reach zero entropy but nevertheless it manifests entropy reduction compared to an energetic non-optimal raw material doesn't it? meaning if we need less energy for the same amount of work we do it more efficiently and therefore require less (but not null!) entropic output
- deleted 7y ago[deleted]
- tosh 7y agopaper: https://www.nature.com/articles/s41586-019-1751-9 https://www.nature.com/articles/s41586-019-1751-9
- dclowd9901 7y agoThey kept referring to IoT uses in the article. It got me wondering if the best usage of this would be to be embedded in a jacket’s outer shell. You get the surface area but not a lot of wattage of heat, I guess. But it sounds like it makes a pretty good insulator. I could certainly imagine sensors running off that kind of power.
- grecy 7y agoI've always wanted to build a little hobby project where I put TECs on top of my wood stove and have a radiator outside with coolant to get a nice big heat difference (maybe 100C to 200C) across them and make power in winter when solar isn't so great in the Yukon. I know it won't be a massive amount of power, but given it will be 24/7 for about 6 months of winter when the wood stove runs, I think it will be a useful amount. Does anyone know where I can buy TECs that will handle extremely high temperatures like this? All the ones I see say they're rated at about a max temp delta of ~67C-72C
- gwbas1c 7y agoHow much power are you trying to make? You can already buy "off the shelf" USB power supplies for camp fires
- grecy 7y agoAs much as possible. I would probably cover the entire top of the stove in TECs (so maybe something like 0.5m^2). If I wanted to I could play with adding some to the sides, onto the chimney, etc. Essentially, it's just to supplement the solar which as I said isn't so crash hot in the Yukon in winter. It's a hobby, and I'd like to see what I can get out of it. Again, because it's 24x7 for ~6 months I think it might be a fun side project to play with and watch what I can get out of it.
- kragen 7y ago> How much power are you trying to make? > As much as possible. That is not a useful response. Would it be worth doing if "possible" turned out to be 0.1 mW? 1 mW? 10 mW? 100 mW? 1 W? 10 W? 100 W? 1 kW? 10 kW? Presumably somewhere in that sequence your answer goes from "no" to yes" and that point determines what tradeoffs you're going to be willing to accept in order to increase your power capacity. People have suggested steam engines. Those would definitely produce more power than TECs, at least twice as much and potentially six times as much. But they are far more likely to kill you. Is that tradeoff worth it to you? TECs are pretty expensive per watt. Are you really willing to spend tens of thousands of dollars if it will increase your energy output a little? How about hundreds of thousands? There are tradeoffs in any engineering design. It's obvious that more power is better, but without some idea of the shape of your utility curve, it's impossible to evaluate those tradeoffs in a useful way.
- jasondclinton 7y agoDoes anyone know if this discovery can be used to boost the efficiency of solar panels? Don't solar panels get incredibly hot?
- vermilingua 7y agoThe title is misleading, the technology (thermoelectric cooler) does not turn heat into electricity, but temperature gradients. It needs a nearby source of cool to work, and when a solar panel is hot, oftentimes everything surrounding it is hot.
- BurningFrog 7y agoMy intuition says the shaded ground below it can be quite a bit colder. I have no real data...
- icegreentea2 7y agoYou can use these types of materials to extract energy from any energy gradient. In the particular case of solar panels, in order to have a workable thermal gradient, you need to have some sort of conductive path from the solar panel to the cold reservoir (assume the ground under it) - that's extra cost there. Then once you have the TEG running, what you're actually doing is adding an impediment to heat flowing from the solar panel to the cold spot, likely causing the solar panel to be a bit warmer (thus decreasing its efficiency). The increase in energy production per given investment is almost always going to be lower than just getting more solar panels. You see this is most bulk energy production contexts. It's rare for these energy scavenging techniques to make economic sense. Where you start seeing them make sense is when you have other constraints come into play. You can see this with other aspects of solar generation like solar tracking.
- pharke 7y agoIf an advanced civilization continued to improve the efficiency of this effect would they eventually use it to capture the majority of the energy output of their local star? You could have a shell of high efficiency solar satellites surrounded by another shell of high efficiency Seebeck satellites. What would this look like from a distance? Would they be able to capture enough energy so their star would be indistinguishable from the ambient temperature of space? Our galaxy and others appear to be missing most of the mass i.e. stars that they should have in order to rotate as fast as they do. We put the figure for missing mass at about 80 to 90 percent for our galaxy. What if our galaxy and others are already colonized by advanced civilizations that make maximal use of the power output of stars so it simply looks like we're missing most of the matter that should exist. This could explain why there is a variation in the amount of missing mass between galaxies with some galaxies apparently containing 0% 'dark matter'. No advanced civilization = no dark matter, different amounts = different stages in development of the galactic civilization. Could this be a solution to the Fermi paradox?
- bwanab 7y agoSounds like a good beginning to a collaboration novel by Neal Stephenson and Alastair Reynolds.
- etimberg 7y agohttps://en.wikipedia.org/wiki/Dyson_sphere https://en.wikipedia.org/wiki/Dyson_sphere
- justAnotherNET 7y agoThis is both horrific and fascinating. I’ve never even considered that option as an answer to “dark matter”/unexplained mass.
- deleted 7y ago[deleted]
- bagacrap 7y agoWhat would they use all that energy for, and how would they use it in a way that wouldn't radiate heat or light on par with the amount captured?
- ailideex 7y ago// Removed as I'm not a physicist and may be mistaken.
- lopmotr 7y agoI think it's correct. Heat is the flow of thermal energy. A portion of that flowing energy is converted to electrical energy. Perhaps you're confusing heat with thermal energy? There must be some heat flowing to generate electrical power because of the 1st law, so even if the effect is described as being due to a temperature difference, in practice, you also need a heat flow to be useful. Your quote about "without any side effect" means without heating up a cold reservoir. But the article doesn't claim that.
- zbrozek 7y agoHeat is the energy, not the flow. That flow is flux or power. A temperature difference is how we perceive or measure a difference in thermal energy density between two places, and is the potential that drives heat flux. A thermoelectric barrier between those two wells can extract energy from that flow, within thermodynamic limits.
- lopmotr 7y agoYes, I was a bit sloppy. It's the flowing energy, not the flow of energy. The point of my comment was to distinguish heat from stored thermal energy so the distinction isn't so important in that context.
- comicjk 7y agoJust to clarify why these aren't used everywhere: heat-to-power devices act as insulation (compared to just letting the heat escape). If you have something that you're trying to keep cool, like a CPU, a system that shunts heat straight to the surroundings will always give better cooling than a system that puts layers in between. Contrariwise, if you have a need for electricity, mechanical heat engines will almost always be more efficient. Solid-state heat-to-power only makes sense in a narrow set of cases which aren't suitable for direct cooling or heat engines.
- Matumio 7y agoBut there are some pretty cool applications. Apparently the heat difference between a buried water-pipe and the surrounding earth is already enough to power a wireless sensor, which can transmit data to localize leaks, for example.
- m463 7y agoVoyager 2 and 1 are powered by thermocouples and a chunk of plutonium. (I ordered them that way because Voyager 2 was launched first)
- perl4ever 7y agoSomething I was curious about, but not sure where to start - suppose you wanted to make something that at 400-500K, would emit radio waves from which the temperature could be derived. And as small, simple and durable as possible, so it didn't break down. I mean, there's going to inherently be infrared, so how can you convert that to radio of roughly a desired frequency range without complex machinery?