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New multiferroic alloy turns waste heat into green electricity for free
- trebor 15y agoIf I remember correctly, there was recent talk about the magnetic component of light being much strong than thought. Well, why not focus light on this material and let the heat make a stronger magnetic field and use it as a solar panel?
- ars 15y agoBecause you need a cold sink to make this work. Solar panels need a dark sink, but that's easy to get. You can only convert energy (i.e. do work) when sending energy from high to low, for example hot to cold, light to dark, etc. (If you heated a solar panel to the point that it glowed with the same intensity as the incoming light it would not work. Ignoring the fact that it would melt :) Electric power plants use bodies of water as the cold sink. If you ever see clouds of what looks like smoke, but is really steam while driving, what you are seeing is the cold water evaporating after being used as a cold sink. BTW if you did want a solar-thermal power plant they exist, and don't need this material. It's a lot simpler than that - just concentrate the light to heat water and run a steam turbine. BTW#2 "the magnetic component of light being much strong than thought" doesn't make sense. The magnetic component of light is VERY well understood. You are probably misremembering, or misunderstanding.
- sp332 15y agoI think the magnetic thing was from http://news.ycombinator.com/item?id=2462355 http://news.ycombinator.com/item?id=2462355
- trebor 15y agoSee the other comment for the article/premise I referred to. I'm not a scientist, just a programmer trying to figure out if this'd work. The article stated that the magnetism of light is 100 million times more powerful than previously thought. But, that it must be focused to 10 million watts per cm^2. The premise is that the light induces magnetism that can be drawn as power. Supposedly it requires special materials. But, if you drew the sun's rays to focus on this material to provide heat couldn't it produce a similar use?
- radu_floricica 15y agoI'm guessing its applications would be more in the line of powering remote devices then anything more substantial. I could see the point of replacing a photovoltaic panel with a hunk of metal in a seismic sensor or something like that.
- vineel 15y agoThis looks like it has the possibility to dramatically increase the efficiency of motors and engines. Also, if they could capture the heat coming out of a nuclear reactor, they could both avoid meltdowns and not require proximity to a large body of water. Edit: Disregard this. I don't know thermodynamics as well as I thought I did.
- StavrosK 15y agoIf by "dramatically" you mean "by 0.004%", then yes. More information: http://www.reddit.com/r/science/comments/i6pfi/new_alloy_can_convert_heat_directly_into/ http://www.reddit.com/r/science/comments/i6pfi/new_alloy_can...
- vineel 15y agoI may have been too optimistic. But 30% is still quite a bit. Modern gasoline engines have an average efficiency of 20%. Say you put 100J into one. 20J of useful work will be produced, and 80J of heat. Now if 30% of that heat were captured, that's another 24J of useful work. In effect, we've doubled the engine's efficiency from 20% to 44%. That's pretty dramatic.
- StavrosK 15y agoHmm, where are you getting 30% from? The paper says 0.004%, if I understand it correctly.
- vineel 15y agoThis comment: http://www.reddit.com/r/science/comments/i6pfi/new_alloy_can_convert_heat_directly_into/c21cizq http://www.reddit.com/r/science/comments/i6pfi/new_alloy_can... Which says that the efficiency could reach 30% with some work. I assume that %30 is not a typo.
- StavrosK 15y agoOh, I think 30% is the theoretical maximum. He says they can reach 3% with years of work. It would be great if they could achieve 30%, but I doubt it.
- jcr 15y agoOne application of the alloy is automotive, but there is other work being done in this space: http://news.ycombinator.com/item?id=2687439 http://news.ycombinator.com/item?id=2687439
- asciilifeform 15y agoEpic thermodynamics fail: http://en.wikipedia.org/wiki/Carnot_efficiency#Efficiency http://en.wikipedia.org/wiki/Carnot_efficiency#Efficiency
- ugh 15y agoNot really. (Also: “Epic fail” and a pretty cryptic and lazy link? Doesn’t seem HN worthy.) This obviously doesn’t make perpetual motion machines a possibility and the article reeks of hyperbole but this technology is potentially useful. It would be better to just make stuff that doesn’t produce any waste heat, I guess you could say that this is sort of a step in that direction. It’s for making stuff more efficient, no more, no less.
- regomodo 15y agoIt sounds very similar to a peltier junction.
- asciilifeform 15y ago> a pretty cryptic and lazy link? Doesn’t seem HN worthy If you know of a better intro that I can link to, please post it. > This obviously doesn’t make perpetual motion machines a possibility As if perpetual motion were the only thing forbidden by the laws of thermodynamics. > this technology is potentially useful. To those pushing it. To everyone else, it is a scam, plain and simple. > It would be better to just make stuff that doesn’t produce any waste heat Please, please open a physics textbook. I beg of you.
- hugh3 15y ago* Please, please open a physics textbook. I beg of you.* Even better, I'll go ask a physicist. Ooh, I'm a physicist! Hey hugh3, does this violate the second law of thermodynamics? Uhh, nope, not at all! You can always extract some useful work when transferring heat from a hot bath to a cold bath. Gee, thanks hugh3!
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- khafra 15y agoBasically the same as a seebeck generator; but it can be used in places where current seebeck generators would not do well. I wish they would phrase these things as "turns heat differences into electricity;" because every time they say "waste heat," people get excited about harvesting heat from their CPU and having their computer power itself.
- dspillett 15y agoWell in theory a proportion of the heat generated by a hot running CPU or GPU (or anything else that operates at a temperature significantly higher than the local ambient temperature) could be converted to useful energy, and you could feed the generated power back into the unit to reduce what it needs to sink from other sources. Though of course you would have to work out if the energy savings are enough to outweigh the extra energy used in manufacturing such a device (remembering to account for the fact that the extra complexity of each unit may reduce the effective yield of the manufacturing process). It might cost far more energy to make than it'll ever save in its active life. Thermodynamics can be a bugger like that...
- chadgeidel 15y agoI'm going to play a bit of "devil's advocate" here. :-) The general problem of place-shifting and time-shifting energy (wind power / solar power) is a very real issue and you could make tons of money solving it. This particular application won't of course.
- DanielBMarkham 15y agoI don't want to play grumpy old guy, but I'm getting a bit tired of breathless articles that omit key facts. What's the efficiency? It's such an obvious question I can't imagine writing an article without that data. How about current costs of other green power? Difficultly of the subject area? Others who have tried? I love these new tech stories, but one or two paragraphs of context can go a long way for the reader. We're left having the same old discussion: one person says "awesome!" and then another points out one of these obvious (and common) holes. It's the same discussion, over and over again. It's not just the energy stories. I've seen dozens of startup stories that are long on hype and emotion and really short on explaining the market and how the company is executing -- the key things that any other startup person would want to know. Heck, I know everybody's excited about it, what I want is somebody giving me a bit of perspective. Same goes for "new cancer treatment found!" articles, which are also long on emotion and short on context. I know emotion gets clicks, just wish we could do better here.
- jasonlotito 15y agoNot to disagree with you (you make a good point, after all), but couldn't this be a case of reporting on a minimal viable product? As you say, it happens in tech, too. The idea here is to generate interest. Sure, it's not complete yet, and they probably still have a long way to go, but the idea isn't to present a finished solution that is now going to market. And it's not like reporters want to wait until something is being sold before writing a story, either. I guess for me, as much as I want more information, I'm willing to accept what they are trying to do.
- stdbrouw 15y agoIf they know it's viable they know of its efficiency, potential drawbacks and advantages related to other technologies, so there's no reason why the reporter couldn't have asked for that information.
- NY_USA_Hacker 15y agoEmotion? Of COURSE it's emotion! It's ALL about emotion; the rest is just window dressing. It's to grab you by the heart, the gut, or below the belt, always below the shoulders, never between the ears. It's from a 'culture' that is ingrained and self-perpetuating: In college, they majored not in math, physical science, or engineering but in the 'humanities', especially English literature. There 'truth' is 'compelling' and from emotions or beauty, is in the eye of the beholder, personal, relative, etc. In particular the most desired form of the emotions is 'drama' especially as in formula fiction with good and evil, etc. The foundation is 'art' as in communication, intrepretation of human experience, emotions. Or 'it feels good'. This 'culture' is solidly in control of 'old media'. There are two big reasons: First, old media goes way back, is sitll close to the old morality plays, and goes way back before the revolution in information safety and efficacy starting with, say, J. Maxwell and with grand examples in math, physics, chemistry, biology, engineering, technology, medical science, and medicine of the 20th century. Old media is still locked up well before 1900, mostly 1800. The college humanities majors naturally gravitated to that culture and still do. There are more details in C. P. Snow's 'The Two Cultures'. Second, "The medium is the message" has long held true. In particular, before the Internet, the 'medium' was print, radio, or TV, and there the number of 'channels' and the 'bandwidth' of each channel were so small that the audience had to be very broad and the room for details was very small. So, the 'message' was to low grade emotions and very short. And that's what the article of this thread is. Useful? Rational? No. Emotional? Trivial? Yes. So, obviously 'new media' can exploit more 'channels', would you believe over 100 million blogs, and more bandwidth, how ahout over 5 Mbps download bandwidth? Then we can have 'streams of focused content for focused interests', over 100 million 'streams'. Sure, anyone with anything like an education in math, science, or engineering good enough actually to make things work pays close attention to details, say, efficiency, cost, durability, power levels, etc. Else, computers would snap, crackle, and pop, airplanes would never get off the ground, bridges and buildings would fall, etc. But the English majors in the culture of old media don't care. Old media is dying, and not just because Craig's List is taking their classified ads. HN and your remarks are right on target for how old media is being killed and where new media will be better. My view is that the biggest problem in civilization and our country now is the brain-dead, all-emotions all the time, dysfunctional, self-destructive nonsense of old media instead of the solid information we need to be responsible citizens and direct our government to a better future. E.g., only now, slowly, are we learning the real anatomy of The Great Recession. So, old media never got the word out. Cry about the pains after the disaster? Sure. Have the solid, crucial information to avoid the disaster before hand? NOT a chance. Old media is helpless, full of tears, devoid of rationality or responsibility. With old media, it's surprising we haven't blown up the planet by now. Old media, I have a question: "Now, how does that make you feel?".
- quasistar 15y agoIn materials science labs around the world, researchers are performing 'miracles'. Aerogels could eliminate most of the waste heat from buildings. Piezoelectric nanogenerators could power mobile electronic devices. Graphene transistors could attain speeds of 1THz. And multiferroics like the beastly Ni45Co5Mn40Sn10 mentioned above could replace bulky laptop batteries. But what is achieved with multi-million dollar government sponsored research grants in controlled labs is difficult to transfer to ones doorstep. One barrier is economic: an aerogel house would cost $50M! A pricetag that may be acceptable to the Department of Defense, but won't do Peoria Joe much good.
- SigmundA 15y agoThe whole article acts like we have never discovered thermocouples: http://en.wikipedia.org/wiki/Thermocouple http://en.wikipedia.org/wiki/Thermocouple I mean the voyager spacecraft are powered by them: http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator http://en.wikipedia.org/wiki/Radioisotope_thermoelectric_gen... Along with many gas appliances with pilot lights.
- sliverstorm 15y agoIt could get away with pretending we hadn't- if the efficiency was leaps and bounds greater. Or rather, if they even bothered to comment on efficiency at all.
- georgieporgie 15y agoI don't get it. So you can use heat to make a magnet. We already have permanent magnets. Magnetism, in and of itself, doesn't create energy. You'd have to either pulse the magnet, or move a coil past the magnet. The former seems impossible since you'd have to cycle its temperature, and the latter just gives you an alternator, which we already have. If I'm missing something, I'd like to know. It just looks like, "hey, magnetism!" and some hand-waving.