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.
Discover more from Watts Up With That?
Subscribe to get the latest posts sent to your email.
Computer data centers have a lot of waste heat and consume a lot of electricity. Hmmm.
temperature differences in the ocean
when the temperature is raised a small amount
=====================================================
Wouldn’t the most obvious be to just put it out in the sun?
..what am I missing here?
So stick 2 or 300 in the smokestacks of factories, the cooling towers and pools of nuclear power plants, and the steam pipes of co-generation plants. Or for matter, line hot water heaters with them. My previous house had 2 90 gallon water heaters and a recirculating pump, if I’d had these lining my hot water pipes…….
Great to read about worthwhile research. Compare this to wasted investment on the Mann sea-level study reported on yesterday
I agree this is interesting. My PhD in the 1970’s was in the metallurgy of these types of phase transformation and my first proper job was to try to make a low temperature differential mechanical heat engine using the odd mechanical behavour of these shape memory alloys (I still have the bits in the shed). Direct power generation may be a much better use for this wonderful solid state phase transformation. Thanks Anthony for bringing this to our attention. DaveS
First, you can’t just convert heat into electricity, you can only exploit temperature *differences*. And secondly, if you’re talking about temperature differences, there are already lots of devices for doing that. The Peltier effect used in thermocouples turns heat into electricity.
Keep an eye on the 2nd law.
seems like a new form of thermoelectric … not more efficient it appears … so if its not cheaper I wonder if it has a role to play …
and as fas as using it in a computer … that whole magnetic field thingy is not going to be appreciated by your computer …
I would point out the material doesn’t create electricity … it generates a magnetic field which requires coils to generate electricity …
From what I understand, it’s not that it just requires heat, it requires heat that oscillates around the transition temperature. Think of it as magnet moving through a coil of wire.
It would be nice to know what amount of energy is produced.
@DaveS
Exactly what popped into my mind. Many larger commercial data centers take the outside mains power, rectify it to high current DC, apply that DC across a bank of wet cell batteries and then regenerate AC power for distribution inside the facility. Should mains power fail, the batteries allow time for diesel generators to come online and provide power without interrupting power to the load. The load basically never senses a change in applied power. The ideal place to use these would be in application of DC across that battery bank. That would slightly decrease the load on the mains or the generators and unlike solar, it would work 24×7. In addition, the heat load in the building is directly proportional to electricity consumed. Every watt brought into a data center in the form of electricity must be eliminated in the form of heat. Often the air handling capacity of a data center is the limiting factor on the amount of power they can bring in to power computers. Being able to convert this heat back into electricity would be a major win but I am guessing it would be several years before this could be applied at a cost-effective scale in a data center.
One thing that has also crossed my mind is why these large data centers don’t use PV panels. Many of them have large flat roofs. Placing panels in places like California and Arizona where summers are hot and sunshine is abundant would provide two benefits; it could add additional power on the DC bus across the batteries and shade the roof reducing climate control load at the same time.
The nonsensical untestable quasi-religious theorizing (Big Bang, Global Warming, Dark Matter) gets all the Nobels, but all the real scientific innovation is in Materials Science.
Lattitude: Your suggestion was tried 34 years ago on the Big Island, Hawaii. It was not cost effective. See:
http://en.wikipedia.org/wiki/Natural_Energy_Laboratory_of_Hawaii_Authority
From the lonely corner of the scientifically unschooled, would this contraption be economical for direct electricity generation with conventional fuels? The stress on waste heat hints…to me, at least…that the thing is not economical, but then again, it could be that the “green” angle was included to satisfy the jealous and angry gods of environmentalism at the EPA.
Latitude says:
June 22, 2011 at 10:53 am
temperature differences in the ocean
when the temperature is raised a small amount
=====================================================
Wouldn’t the most obvious be to just put it out in the sun?
..what am I missing here?
It’s not the sun it’s CO2. You have tleave it out in the CO2
By the time I struggled to spell Peltier, I find several replies saying exactly what I was going to say.
It is not a thermoelectric invention, It is using the change in magnetic field to induce an emf in a surrounding coil.
E = -N. deltaThi / deltat where N =number of turns, Thi = flux density and t = rate of change of flux If I remember my generator theory.
If the rate of flux change is proportional to the heating / cooling cycle rate, then unless the material is very finely divided, the rate of change of temp and thus flux will be very slow and the resulting emf will be a gnats whisker of very little.
cheers
P
Nullius in Verba says:
June 22, 2011 at 11:03 am
First, you can’t just convert heat into electricity, you can only exploit temperature *differences*. And secondly, if you’re talking about temperature differences, there are already lots of devices for doing that. The Peltier effect used in thermocouples turns heat into electricity.
The Peltiers available for TEG (thermo-electric generation) use a Tin/Bismuth solder which melts at around 250C. OK if your application has steady controlled temperature, but a bit fragile for more ‘ad hoc’ situations. I’ve been messing with Peltiers to run forced induction fans in my lightweight wood fired cookstove designs.
This material looks more robust, but would need some kind of mechanical intervention to move a heat shield. That will soak up a percentage of the power, although the might be other ways to achieve the desired effect, like periodically water misting the unit with a gravity fed system.
One for mad inventorators to keep an eye on.
This is a more complicated variation on a thermopile, with the efficiency reduced due to the inefficiencies of converting through an electromagnetic induction step.
In any case the thermodynamic efficiency (n) is limited by the temperature difference (T-hot, T-cold) and basic thermodynamics: n <= 1 – T-cold / T-hot.
Given this gadget requires some expensive materials (nickel, cobalt, manganese, tin), it is unlikely to be cost-effective on a production scale.
Who wants to be the one to break it to Paul Erlich that the idiot children of the world are about to be given a whole slew of machine guns?
I’ll volunteer – I’d love to see his reaction to this news.
This looks to be an interesting material but I am not quite so sure of its efficacy in generating useful amounts of electricity. The amount of electricity generated depends on how much the magnetism changes. When it stops changing then no more electricity is produced.
So looking at their fig 1. it would seem that in a car exhaust you would get a low-level double-sided pulse of electricity when the engine warmed and a similar one at the end of the journey when the exhaust cooled.
If it could heat and cool 50 or 60 times a second then we might have something.
Tom Davidson says: June 22, 2011 at 11:41 am
I would doubt that it could be more expensive than a wind turbine. Especially when compared on a cost per generated watt basis.
Oops, forgot the /sarc on my last post.
It sounds like you need an oscillating heat source, not easy to manage. Constant heat source with cooling water pulses might work but to make it efficient, it would need to be thin film which complicates the heat application. I am sure there will be niches for this technology but we already have Peltier junctions and using them to exploit waste heat is not a good ROI.
Neat toy but I wouldn’t invest a nickle in it.
The efficiency of such device must be pretty low considering that it is an indirect method to generate electricity. Organic Rankin Cycles (ORC) engines are already much more efficient and already on market.
There is also the work of Dr. Victor Klimov which I put in the Tips and notes some time ago. Apparently he is much closer to being able to make commercial systems. Here it is again;
May 19, 2011 at 11:05 am
Anthony,
Have you ever heard of Dr. Victor Klimov at Los Alamos National Laboratory? Apparently he has found a way to get free energy from the vaccum and his work has been proven and published.
http://www.cheniere.org/correspondence/042011.htm
http://peswiki.com/index.php/Site:LRP:Victor_I._Klimov_-_%22Energy_From_The_Vacuum%22_-_Verification
http://quantumdot.lanl.gov/
http://dimensionalbliss.com/2011/05/02/victor-klimov-free-energy-system-100-proven/
@Tom Davidson,
Expensive materials? All those materials are incredibly inexpensive, especially compared to any rare earths as are used in batteries. So, I’m not sure what you mean. It’s likely to be extremely cost effective on a production scale.
From the sounds of it, it could be quite an efficiency booster, but itself cannot be an energy producer. It’ll just capture waste to increase efficiency of the actual producer.
One question I have is what do they define as “…when the temperature is raised a small amount”?
Small amount to me is a degree or two or less. Is this a scientific “small amount” based on a small percentage of the whole Kelvin temperature scale, or on the “solar furnace” scale where “what’s a couple thousand degrees between friends” would be a small amount?
Also do these materials, once the temperature change occurs, flip back into their equilibrium state if the temperature stabilizes at the higher value? Does it require constant fluctuation, as one other commenter suggested? There are a whole raft of questions that come to mind when put to the lens of pragmatic application.
OK, I just read the whole article, skimming by the math and unfamiliar materials terms. So the sample was 3 grams, the temperature that transition took place was around 275C, and they tracked a 0.6mV pulse. As a proof of concept, that’s pretty nifty, and at reasonable temperatures. Reading how the material was made, showed that this is a rather esoteric material; this brings to mind the question of mass production. Will the voltage output scale up with the mass of the material in a reasonable fashion. They touch on the shape of the material having some bearing on its properties, as well.
As I said, this is a really nifty development. Boy, do they have a whole lot of work to do! Get on it guys! I want cheap electricity. 🙂
Gosh, this is why I love this site…… I’m reading this paper getting all excited about our new-found device that could revolutionize the green revolution!!!!!!
I continue reading…..nagging voice inside my head starts….. I’m reading …… starting to look as some of it as not nearly as cool as I was hoping…… reading ….nagging voice gets louder…… realizing magnetic fields are energy forms…. realizing it takes a bit of energy to set up the scenario the papers assumes…..nagging voice says “go back to WUWT and click refresh….”…… OIC, some are a bit quicker than me…. 😐
Hopefully they can do some refinements and find a niche to where it could add to the efficiency of something in a cost effective manner.