From the University of Minnesota via Eurkealert today, this looks interesting:
University of Minnesota engineering researchers discover source for generating ‘green’ electricity
University of Minnesota engineering researchers in the College of Science and Engineering have recently discovered a new alloy material that converts heat directly into electricity. This revolutionary energy conversion method is in the early stages of development, but it could have wide-sweeping impact on creating environmentally friendly electricity from waste heat sources.
Researchers say the material could potentially be used to capture waste heat from a car’s exhaust that would heat the material and produce electricity for charging the battery in a hybrid car. Other possible future uses include capturing rejected heat from industrial and power plants or temperature differences in the ocean to create electricity. The research team is looking into possible commercialization of the technology.
“This research is very promising because it presents an entirely new method for energy conversion that’s never been done before,” said University of Minnesota aerospace engineering and mechanics professor Richard James, who led the research team.”It’s also the ultimate ‘green’ way to create electricity because it uses waste heat to create electricity with no carbon dioxide.”
To create the material, the research team combined elements at the atomic level to create a new multiferroic alloy, Ni45Co5Mn40Sn10. Multiferroic materials combine unusual elastic, magnetic and electric properties. The alloy Ni45Co5Mn40Sn10 achieves multiferroism by undergoing a highly reversible phase transformation where one solid turns into another solid. During this phase transformation the alloy undergoes changes in its magnetic properties that are exploited in the energy conversion device.
During a small-scale demonstration in a University of Minnesota lab, the new material created by the researchers begins as a non-magnetic material, then suddenly becomes strongly magnetic when the temperature is raised a small amount. When this happens, the material absorbs heat and spontaneously produces electricity in a surrounding coil. Some of this heat energy is lost in a process called hysteresis. A critical discovery of the team is a systematic way to minimize hysteresis in phase transformations. The team’s research was recently published in the first issue of the new scientific journal Advanced Energy Materials.
Watch a short research video of the new material suddenly become magnetic when heated: http://z.umn.edu/conversionvideo
In addition to Professor James, other members of the research team include University of Minnesota aerospace engineering and mechanics post-doctoral researchers Vijay Srivastava and Kanwal Bhatti, and Ph.D. student Yintao Song. The team is also working with University of Minnesota chemical engineering and materials science professor Christopher Leighton to create a thin film of the material that could be used, for example, to convert some of the waste heat from computers into electricity.
“This research crosses all boundaries of science and engineering,” James said. “It includes engineering, physics, materials, chemistry, mathematics and more. It has required all of us within the university’s College of Science and Engineering to work together to think in new ways.”
Funding for early research on the alloy came from a Multidisciplinary University Research Initiative (MURI) grant from the U.S. Office of Naval Research (involving other universities including the California Institute of Technology, Rutgers University, University of Washington and University of Maryland), and research grants from the U.S. Air Force and the National Science Foundation. The research is also tentatively funded by a small seed grant from the University of Minnesota’s Initiative for Renewable Energy and the Environment.
For more detail on the research, read the entire paper published in Advanced Energy Materials at http://z.umn.edu/energyalloy.
The Direct Conversion of Heat to Electricity Using Multiferroic Alloys
Vijay Srivastava1, Yintao Song1, Kanwal Bhatti1,2, R. D. James1,*
Abstract
We demonstrate a new method for the direct conversion of heat to electricity using the recently discovered multiferroic alloy, Ni45Co5Mn40Sn101. This alloy undergoes a low hysteresis, reversible martensitic phase transformation from a nonmagnetic martensite phase to a strongly ferromagnetic austenite phase upon heating. When biased by a suitably placed permanent magnet, heating through the phase transformation causes a sudden increase of the magnetic moment to a large value. As a consequence of Faraday’s law of induction, this drives a current in a surrounding circuit. Theory predicts that under optimal conditions the performance compares favorably with the best thermoelectrics. Because of the low hysteresis of the alloy, a promising area of application of this concept appears to be energy conversion at small ΔT, suggesting a possible route to the conversion of the vast amounts of energy stored on earth at small temperature difference. We postulate other new methods for the direct conversion of heat to electricity suggested by the underlying theory.
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Dave Springer, NikFromNYC, and Atomic Hairdryer:
Thankyou for your responses to my post at June 22, 2011 at 1:42 pm which you provide at June 22, 2011 at 4:33 pm, June 22, 2011 at 4:33 pm and June 22, 2011 at 4:34 pm, respectively.
As pertinent anecdote, I point out that the only novel material I devised was the Foseco candle filter medium which had the benefit of being strong during installation but then sacrificed unneeded operating strength for needed operating toughness in response to shock (i.e. impact stress) from reverse pulsing. So, I fully appreciate the point made by Dave Springer who responds to my having said;
“The novel material we really need is a room-temperature superconductor. That would change the world.”
With the comment;
“Not unless it’s also cheap, ductile, and doesn’t lose superconductivity in magnetic fields. Good luck with that.”
Of course, he is right. As my anecdote illustrates, a novel material for an intended specific purpose needs to be capable of withstanding a range of conditions and circumstances. But “luck” has nothing to do with this. In every case, the problem is constrained by physics, chemistry and the ingenuity engineers can apply to the materials that material scientists devise and/or suggest for specific applications.
As illustration, aluminium has high electrical conductivity so is good for electrical transmission lines but has high creep rate so is impractical for use as electrical transmission cables. Engineers overcome this by using lines which are a supporting core of steel wire surrounded by aluminium (i.e. duralumin alloy).
So, I think what I said and the response of Dave Springer both have merit.
NikFromNYC quoted my saying:
“There is a problem with gaining research funds for novel materials: i.e. potential funders ask “What use is it?” and they expect an answer. So, researchers need to give an answer because no real use will ever be found if the research is not conducted.”
Then he commented;
“This was the modern age bummer that set such a divide betwen the old and new school that helped turn me away from academia, way back in the late ’90s.”
I thank him for that anecdote. It clearly illustrates a problem that research in all scientific fields now has. The best researchers now tend to seek work in commercial and/or military research facilities and, therefore, much of the best work does not get published – so cannot be utilised – in the public domain for at least 30 years if ever. I think this is one reason why the flow of radically new scientific findings up to about 1970 has since trickled to a halt (of course, this is mere opinion and I cannot substantiate it).
Atomic Hairdryer says:
“I think Richard S. Courtney may be right and this material ends up more useful for it’s magnetic properties.”
I remind that I pointed out that not all material properties that change with temperature prove useful. The novel multiferroic alloy may or may not have a use, and we need to wait to find that out.
Again, thanks to you all for your interest in what I wrote.
Richard
I agree 100% with everything scientist for truth says here. (June 23, 2011 at 4:40 am)
I hope this is the first of many occasions I’ll be able to say that.
🙂
Simply use a LENR device to rotate the material through a heat gradient and get all the free energy that magical thinking can produce.
I haven’t read all the comments, so maybe it’s been mentioned … but … I wonder if this technology can be used to generate electricity from heat generated by the sun .. and how efficient it would be compared to photovoltaics.
OK .. I see the sun has been discussed. Apparently it is the temp gradient that produces the electricity. One post mentioned how to cool it …. How bout water??
Let it heat up .. generate electricity .. .then cool it with gravity feed water.
This is not a joke is it? What does a thermocouple do? What about the Seebeck effect? Why are these not powering the engines of manufacturing today?
University of Minnesota + ANDREA ROSSI =DREAM TEAM ?
Deanster says:
June 23, 2011 at 5:56 am
“I haven’t read all the comments, so maybe it’s been mentioned … but … I wonder if this technology can be used to generate electricity from heat generated by the sun .. and how efficient it would be compared to photovoltaics.”
Utterly dismal in comparison. This is a very promising way to greatly reduce the weight of RTG power supplies used in deep space exploration. Those use traditional thermoelectric banks (dissimilar metals in physical contact) with about 1000F temperature gradient produced by a decaying mass of plutonium across the thermocouples and are about 5% efficient which is in the same ballpark as photovoltaic efficiency. The big differences are cost and operating environment. PV panels are several orders of magnitude less expensive to manufacture and don’t need any temperature gradient at all. Concentrating sunlight to heat any substantial mass to 1000F is expensive in and of itself. The only reason solar panels aren’t used in deep space probes is because sunlight rapidly falls in intensity as distance from the sun increases. They’re fine for missions closer to the sun but don’t produce enough power once you get much beyond the orbit of Mars. RTG power supplies are hideously expensive mostly due to the price of plutonium and they are so heavy they account for about half the weight of the payload. In turn the weight of the payload is itself the single largest cost factor in the project due to how expensive it is to boost mass from the earth’s surface to escape velocity from the sun. Often complicated slingshots around various planets are employed to add delta-V which adds years to the time it takes to reach a destination, makes for very narrow launch windows, but greatly reduces launch costs. It’s potentially a wonderful technology for a very limited range of applications. Unfortunately none of those applications fall into the category of replacement for existing bulk electrical generation in common everyday use.
Richard S Courtney says:
June 23, 2011 at 5:02 am
When it comes to high temperature superconductors luck has everything to do with it. Theory only describes low temperature superconductors. There is currently no theory of high temperature superconductivity so discovering them is indeed purely a matter of luck.
ScientistForTruth says:
June 23, 2011 at 4:40 am
Low quality heat is just that. It would be wonderful if you could make an efficient heat engine using water raised to say 100F over ambient which is really easy to do with inexpensive solar collectors. Before you stick your foot any further into your mouth you need to figure out why no one has accomplished this feat after 200 years of trying. You might want to begin with Carnot’s Law instead of blithering on about the laws of thermodynamics and your supposed graduate level studies in physics. What a laugh.
Isn’t the problem here that the induced electricity is caused by the phase transition as a result of the temperature change. That means that just exposing it to heat gives you the kick only once, when the material warms up. In order to generate useful power the device has therefore to go through an endless cycle of warming and cooling
around the transition temperature. That would need some device to control the temperature. The question is then, does operating that device cost more or less than the electric power generated? An interesting engineering challenge.
re; heat engines using low quality heat
Ammonia is an interesting working fluid in that it vaporizes at a convenient temperature for simple solar collectors. The inevitable engineering problem one faces is that you need slow moving pistons the size of 55 gallon drums to get usable amounts of mechanical energy. Friction losses in piston cylinders that size are formidable and is compounded by the losses in a gearbox that steps up the very slow primary crankshaft speed to an RPM range suitable for an electrical generator shaft. Throttling it to a constant speed for an alternator or generator is yet another engineering nightmare and if you don’t do that then you need to use expensive lossy solid state electronics to generate a steady 120VAC at 60 hertz.
Indeed the first steam engines using low pressure boilers incorporated huge pistons like that. Gadgets that size are not suitable for very many applications and even so low pressure steam is still a few hundred degrees above ambient and that’s not easily attainable by inexpensive solar collectors which are generally limited to something a few tens of degrees south of 212F. Low pressure steam (low quality heat) is wonderful for transmitting energy from one place to another which is why there are still thousands of miles of steam pipes running beneath older cities but it’s all being used to heat buildings which is about the only practical application for low quality heat.
Steam turbines abound in electrical generation but these are driven by dry steam in the neighborhood of 2000F inlet temperature. Multiple stage turbine fans take it down to about 500F at the outlet which is the practical lower limit for direct extraction of further mechanical energy sufficient to econimically overcome parasitic losses. In combined cycle generation the low quality heat from the turbine outlet steam is scavenged to preheat water coming into the boiler but the scavenger system isn’t free of cost and once the steam reaches condensation temperature it’s pretty useless after that as there’s no latent heat of vaporization left to extract leaving just a hundred or so BTU’s per pound of hot water which can be used to heat the generator buildings if it’s cold outside but has no other practical use.
Carnot Efficiency = 1 – (Tc/Th)
This is the maximum possible efficiency for an idealized frictionless heat engine. Tc is the ambient temperature and Th is the inlet temperature both in Kelvin.
Thus for say a steam engine operating at 500F inlet temperature exhausting into 70F ambient the maximum possible (Carnot) efficiency is
1- (294/533) = 45%
That’s all well and good but in the real world no one has been able to design a practical heat engine with fewer than 45% in parasitic losses. The best combined cycle steam turbine generators operate at 65% efficiency which handily explains why the exhaust steam temperature is 500F.
The take home lesson here is that there’s a wide divide separating scientists from engineers. Physics boffins lacking engineering expertise should stick to theory and put a sock in it when it comes to translating theory into practical application. When that border is crossed we get huge multi-billion dollar boondoggles like hot fusion reactors where the scientists get all excited about exceeding break-even for a few milliseconds and happily ignore the fact that no known material in the world can stand up for a month as the inner walls in a fusion containment vessel.
That’s not to say engineers are immune to crossing over into the domain of scientists and saying foolish things in the process. They tend to see any quasi-scientific discovery that has yet to be vetted (cold fusion comes to mind) as something revolutionary in practical value and start drooling on their drafting tables like Pavlov’s dog. I try very hard to not do this myself and usually look at things from both perspectives with a jaundiced eye. Currently I’m still trying to find what if any roadblocks there are between genetic engineering and very economical biofuel production. So far I can’t find any which is why I remain convinced that is the future for energy demand and it’s only a relatively short amount of time before the genetic engineers give the manufacturing engineers exactly what they need. It’s not even a matter of scientific discovery at this point. It’s entirely an engineering challenge and I’ll be darned if I can find any showstoppers in the engineering challenge.
It’s certainly a cool little device – I want one just to play with. Although I share the doubts of many commenters about the conversion efficiency of the process, I can also remember growing up in the 60s, when the laser was described as “the solution looking for a problem”; if this can be put to work, perhaps by developing a way of cycling it quickly enough, I’m sure it will be.
I immediately thought of the Seebeck effect myself in the context of waste heat utilisation. I remember seeing, in the RSGB magazine sometime in the 70s, mention of a neat thermoelectric generator used in occupied Norway in WWII. A considerable number of dissimilar metal fins were formed into a sheath which wrapped neatly around a hurricane lamp or similar, and it generated sufficient electricity from the heat differential across it to keep the battery of your (clandestine) wireless charged. Nice.
Dave Springer “Low quality heat is just that. It would be wonderful if you could make an efficient heat engine using water raised to say 100F over ambient which is really easy to do with inexpensive solar collectors. Before you stick your foot any further into your mouth you need to figure out why no one has accomplished this feat after 200 years of trying. You might want to begin with Carnot’s Law instead of blithering on about the laws of thermodynamics and your supposed graduate level studies in physics. What a laugh.”
What a nasty response! I never mentioned my own studies in physics, but since you intrude that little word ‘supposed’, then for the record, yes, I did read physics, which included thermodynamics, at the University of Oxford. Please in turn let me know where you studied your thermodynamics.
As for the laws of thermodynamics, I was correcting the mistaken understanding of such laws given in previous posts and raised by such commenters. Rather than making ad hominem remarks, perhaps you would like to point out exactly what I wrote that was objectionable. Carnot’s theorem that you mention as a law is merely the result of applying the Second Law of Thermodynamics to heat engines, i.e. a special case of the Second Law, so what’s your point?
There is no such thing in physics as ‘low quality heat’, as if heat were a substance that comes in degrees of quality. Heat is not enthalpy, nor is it temperature, nor is it entropy, neither can heat be stored, but it is energy in transfer. You can only talk about ‘low quality heat’, or ‘waste heat’, or ‘secondary heat’ conventionally or in layman’s language, not principially as in physics and thermodynamics. Wherever you have heat then you have energy in transfer, and if you don’t have energy in transfer you can’t have heat. Energy cannot be stored as heat. Sorry, folks, but if this sounds strange then your concept of ‘heat’ is not that of physics and thermodynamics, though it’s a very common misapprehension.
Whether this device can work or not will be down to physics, not layman’s terms or understanding or the traditional know-how of boiler makers. Whether it can be commercialized is another matter entirely, and was not in view in my comment. That’s why I said ‘Without passing judgment on whether this device and phenomenon is any use or not (it’s too early to say), I really must take issue with some of these comments on thermodynamics.’
Of course a heat engine can work with water heated by solar irradiation, but as you well know the maximal efficiency will be very low if the heat sink is at ambient temperature. But that’s not my point: my point is, as readers can see for themselves, that devices that can produce electricity from heat cannot possibly be in breach of the Second Law, as some commenters were suggesting. That, after all, is how we produce nearly all our electricity today.
Dave Springer:
At June 23, 2011 at 7:19 am you assert to me:
“When it comes to high temperature superconductors luck has everything to do with it. Theory only describes low temperature superconductors. There is currently no theory of high temperature superconductivity so discovering them is indeed purely a matter of luck.”
So, you do not know of a theory for “high temperature superconductors”. Well, it depends what you mean by “high temperature”. Superconductors cooled by liquid nitrogen now exist and were unimagined before 1986. Indeed, they are called ‘high-temperature superconductors’.
I said;
“The novel material we really need is a room-temperature superconductor. That would change the world.”
It would, and I suspect that if the monies now provided for AGW so-called ‘science’ were offered for research into room-temperature superconductors then there would be a plethora of hypotheses and theories presented for evaluation.
A useable high temperature superconductor would change civilisation more – and more rapidly – than the industrial revolution.
Richard
More exciting than demonstration of the physical effect, would be the demonstration of a working application, such as a generator of electricity employing the phenomenon.
Okay so it heats up the nickel alloy, gives a surge of magnetics generates a pulse of current….. and then what? Do you have to cool it down and then heat it again? I suppose it also is a cooler – a generator and a refrigerator at the same time.
ScientistForTruth says:
June 23, 2011 at 4:40 am
“Design a second heat engine that operates between the ‘waste heat’ temperature as a heat source and a lower temperature heat sink and you can extract more energy…”
The problem, generally, is how practicably to access that lower temperature heat sink. In automotive applications, for example, being near the source of heat means the proximate ambient sink is not much lower.
Maybe a niche product with possibly good but limited applications. Not the panacea most are looking for.
J.
You can already double the efficiency of cars by fitting diesel engines. Why would you add some heavy and expensive bit of junk just to power your radio?
@scientistfortruth
“There is no such thing in physics as ‘low quality heat’”
Correct. It’s an engineering term and a damned important one too. I suggest you augment your “physics readings” at Oxford with some readings in the history department about the evolution of steam engines whereupon you will hopefully gain some understanding of the term “low quality heat”. Get back to me when you’ve gained that understanding because without it you’re just blowing hot air.
@richard courtney
“A useable high temperature superconductor would change civilisation more – and more rapidly – than the industrial revolution.”
How so? It would make electrical generation, storage, and transmission much more efficient to be sure and electric motors would be more effecient as well. If I thought about it for a while I could figure out how it might benefit computer design too but I don’t see how that translates into changing the world more and more rapidly than the industrial revolution. Copper losses just aren’t that big of a deal. What am I missing?
Steve C says:
June 23, 2011 at 10:15 am
“I immediately thought of the Seebeck effect myself in the context of waste heat utilisation. I remember seeing, in the RSGB magazine sometime in the 70s, mention of a neat thermoelectric generator used in occupied Norway in WWII. A considerable number of dissimilar metal fins were formed into a sheath which wrapped neatly around a hurricane lamp or similar, and it generated sufficient electricity from the heat differential across it to keep the battery of your (clandestine) wireless charged. Nice.”
Hah! Replace the hurricane lamp with a chunk of plutonium and you have the same device except it’ll operate in a vacuum and won’t need refueling for decades.
Necessity is, as they say, the mother of invention. Another device that saw a lot of use in WWII Europe was the syngas generator. Petrol was critically needed for the war effort and some clever inventor found that if you mounted a wood burning stove with limited air supply to the back of a vehicle (cars and tractors for instance) it would produce copious amounts of carbon monoxide and a smaller amount of methane. And if you filtered the soot out and tars out of the vapors through a water bath and fed it into the air intake of an internal combustion engine the engine would happily burn the CO instead of petrol. Syngas generators are making a bit of a comeback. I spent a few days reading all about them a year or three ago.