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Building Material Absorbs and Releases Heat

samzenpus posted more than 2 years ago | from the cool-house dept.

China 98

Zothecula writes "Researchers at the Ningpo, China campus of the University of Nottingham (UNNC) have created a new heat-regulating material that could be used to cut the heating and cooling costs of buildings. The non-deformed storage phase change material (PCM) can be fixed so that it starts absorbing any excess heat above a pre-determined temperature and releasing stored heat when the ambient temperature drops below the set point. The researchers say the material can be manufactured in a variety of shapes and sizes, even small enough so that it can be sprayed as a microscopic film to surfaces in existing buildings."

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98 comments

Doesn't everything do that? (1)

Anonymous Coward | more than 2 years ago | (#36979538)

I'm pretty sure that almost every substance on earth "absorbs and releases heat".

Unless... (4, Informative)

Vario (120611) | more than 2 years ago | (#36979754)

Yes, every material absorbs and releases heat.

The interesting bit here is something different though. I have never seen that someone wants to use a phase change material for buildings, but why not? For coffee cups this already works nicely. The walls of the mug contain a material that is undergoing some phase transition (liquid to solid, different crystalline structure, magnetic, etc.) at a temperature that is slightly below really hot coffee but still a nice drinking temperature.

What happens is the following: the thermal energy of the coffee gets absorbed quickly by the material, therefore cooling it down fast from really hot to a lower temperature. The material can store a large amount of thermal energy and releases it slowly so that the coffee stays at a constant temperature for much longer (gizmag article [gizmag.com]).

For a whole building this makes a lot of sense as well. It more or less acts as a large thermal reservoir, so that your wall temperature does not increase during the day and falls too much during the night. You could achieve a somewhat similar effect by using 20 inch stone walls but this might be a bit easier to incorporate into modern buildings.

Re:Unless... (2, Informative)

Anonymous Coward | more than 2 years ago | (#36979922)

It's been done for a long time.
Southern yellow pine resin has its phase change at about 71F. The first reference in google is from 2007 but it's been know about for a long time before that,

Re:Unless... (1)

jbengt (874751) | more than 2 years ago | (#36980192)

I have never seen that someone wants to use a phase change material for buildings . . .

Ice is a phhase change material that has been in use for a long time.

Re:Unless... (1)

demonlapin (527802) | more than 2 years ago | (#36980612)

Alas, the phase change to liquid does render it less suitable for buildings. Perhaps you meant that ice (or even better, packed snow) has long been used in cold climates for its high insulation value?

Re:Unless... (1)

jbengt (874751) | more than 2 years ago | (#36984708)

No, but ice has long been used in cooling systems to reduce the peak demand and take advantage of lower night-time temperatures.

Re:Unless... (1)

MonsterTrimble (1205334) | more than 2 years ago | (#36985286)

Mod up!

I live in Winnipeg, Canada and two winters ago my basement's record low was 8C. Last year I did two things: First I repaired the fascia covering the front of the house's foundation using $20 worth of spray foam and plaster crack fill. (did wonders for drafts). I also banked up the snow around the house 4 to 5 feetr high. I think the lowest temperature down in my basement was 15C.

Re:Unless... (1)

dotancohen (1015143) | more than 2 years ago | (#36983740)

What happens is the following: the thermal energy of the coffee gets absorbed quickly by the material, therefore cooling it down fast from really hot to a lower temperature. The material can store a large amount of thermal energy and releases it slowly so that the coffee stays at a constant temperature for much longer (gizmag article [gizmag.com]).

Actually, that article specifically mentions that PCMs are currently in use as building materials. Interesting.

Re:Doesn't everything do that? (1)

Midnight Thunder (17205) | more than 2 years ago | (#36985284)

Certainly, but I imagine is when it absorbs and when it releases. Heavy stone and ceramic seems to be the best here. If you look at old buildings you will see the benefit since they absorb the heat when hot and release the environment is cooler.

I haven't read the article yet, so I would be curious to see how complicated and how much better it is over existing materials.

BTW one thing I have been looking at is paint with ceramic beads. The problem I have with it at the moment is cost and availability in Canada.

Absorbs AND Releases? (3, Insightful)

Jeremiah Cornelius (137) | more than 2 years ago | (#36979544)

Whoa! Just like... matter!

Can I patent this thermodynamics stuff?

Re:Absorbs AND Releases? (4, Informative)

Richard_J_N (631241) | more than 2 years ago | (#36979656)

If it performs a phase change at a specified temperature, it means that there is a lot of extra thermal "capacitance" at one particular temperature. If we can choose that temperature to be, say 20 degrees C, this is useful. It would be a bit like water ice. As the freezer temperature falls from +1 to -1 degree, the ice releases a *lot* of stored heat (latent heat of fusion).

So, yes, this is a bit like building a large stone structure, which stays at a constant comfortable temperature by averaging out cold nights and hot days...but we don't need so much mass, and we can choose the temperature we want.

Re:Absorbs AND Releases? (1)

Anonymous Coward | more than 2 years ago | (#36979726)

This is only helpful if you have constant temperature changes. If you live someplace where it's 80 during the day, and 60 at night, and you want it to be 75, this could help. However, if you live someplace where even at night, it's hotter than you want it to be, this does no good at all. It's not going to be able to store up a whole summers worth of heat to release in the winter. During the time period between needing heat, and needing AC, we generally just leave the heater and ac off, and deal with the temperature fluctuations.

Re:Absorbs AND Releases? (1)

lessthan (977374) | more than 2 years ago | (#36980648)

What? There aren't many places that don't have temperature changes. I live in Pennsylvania. Tomorrow is forecast to have a high of 86 and a low of 67 (or a high of 30 and a low of 19 if you are measuring properly). That sounds like a proper variance to me. I imagine that any desert or temperate location would benefit from this material. Tropical and polar locations would be screwed, but who cares about Greenland?

Re:Absorbs AND Releases? (0)

Anonymous Coward | more than 2 years ago | (#36981556)

I live in the midwest, hardly tropical. We haven't had an overnight low of less than 75 degrees in the past 3 weeks. Yesterday we broke records for the daytime high.

Re:Absorbs AND Releases? (1)

hedwards (940851) | more than 2 years ago | (#36982102)

I'd venture that it's not common enough to represent a problem. Around here the best solution in most cases to regulating temperature in homes is to close all the windows and draw the drapes during the day and open all the windows at night.

It' abnormal for us to have a low that's high enough to screw up that system. And it works for most folks. Vulnerable people do still need AC though.

Re:Absorbs AND Releases? (1)

Quirkz (1206400) | more than 2 years ago | (#36986084)

So, 3 weeks of unusual weather means this can't help during the 26 weeks of the year when temperatures would cross the threshold daily?

Here in Colorado this would be perfect. Daytime temperatures often swing 30 degrees or more, with daytime highs that are generally a bit warmer than is pleasant, and night-time lows that are generally a bit chilly.

Re:Absorbs AND Releases? (0)

Anonymous Coward | more than 2 years ago | (#36982194)

High of 30, low of 19, desired temperature in the house 20, after a couple days it'll be at capacity.

Re:Absorbs AND Releases? (1)

sgt scrub (869860) | more than 2 years ago | (#36984912)

Tomorrow is forecast to have a high of 86 and a low of 67

First, as a Texan with an air conditioner strapped to his ass in a loosing battle to stay below 100 degrees, I would like to say, "I hate you". Second... No. That is all I wanted to say. :p

Re:Absorbs AND Releases? (1)

operagost (62405) | more than 2 years ago | (#36985530)

It got up to 100 degrees in PA for several days in the last week or so. Feel better?

Re:Absorbs AND Releases? (1)

sgt scrub (869860) | more than 2 years ago | (#36985948)

It is hard to tell. The latches are digging into my sides pretty bad. But, sure a little.

Re:Absorbs AND Releases? (0)

Anonymous Coward | more than 2 years ago | (#36981684)

Nope. If used in combination with ac/heating, it could allow for more flexible timing of usage, allowing residents to turn it on when electricity is at its cheapest. Would go really well with smart grids

Re:Absorbs AND Releases? (2, Informative)

icebike (68054) | more than 2 years ago | (#36979886)

Nothing new here.

Phase change applications were fairly commonly installed in houses back in the late 70s. Usually a liquid to gel phase change but some were liquid to solid.

The problem then as now, was finding something that changed at the desired temperature, because any time you have to concentrate the heat to reach the the temperature where phase change occurred you lost much if not all of advantage of using these materials. (You essentially ended up running a air-source heat pump to concentrate hot house air into the material).

Being able to set the phase change point is all well and good if it works, and you can plan AHEAD to have your building to be at certain temperature, or can use the material to collect direct solar radiation.

By the way, there is nothing that says a phase change necessarily makes for a "lot of extra thermal capacitance". Its true of water, (something like an 80 fold increase in heat/per-weight-unit going from ice to water or back, IIRC), but not all materials have this property. Presumably materials selected for this use would be good at this. This was not the case back in the day when I last worked with phase change material for residential use. It was pathetic compared to water.

Re:Absorbs AND Releases? (2)

godel_56 (1287256) | more than 2 years ago | (#36980062)

Nothing new here.

Phase change applications were fairly commonly installed in houses back in the late 70s. Usually a liquid to gel phase change but some were liquid to solid.

The problem then as now, was finding something that changed at the desired temperature, because any time you have to concentrate the heat to reach the the temperature where phase change occurred you lost much if not all of advantage of using these materials. (You essentially ended up running a air-source heat pump to concentrate hot house air into the material).

Yeah, here's two more: http://www.gizmag.com/ravenskin-insulation-delays-heat-transfer/17056/ [gizmag.com] http://www.fraunhofer.de/en/research-topics/construction/microencapsulated.jsp [fraunhofer.de]

I think the second one looks cheap and interesting. They use a micro-encapsulated tailored wax which can be mixed into plaster wall boards, giving them the thermal capacity of a brick wall.

Re:Absorbs AND Releases? (0)

Anonymous Coward | more than 2 years ago | (#36984216)

I am amazed that you are not modded up to 5. Just reading about the BASF stuff and it sounds like it is already on the marketplace. Basically, the Chinese are just trying to copy what the Germans are doing.

Re:Absorbs AND Releases? (1)

mattack2 (1165421) | more than 2 years ago | (#36992892)

It was pathetic compared to water.

Within the past year or two there was a house for sale whose owner had died. He was apparently known in environmental circles. The house had water jugs on levers that you could tilt up or down to catch the suns rays, then close it up and have the heat come into the house at night. (It also had a roof water heater, and one of the other people looking at the house said the temperature on the roof water heater was very high, but I don't remember what temp it was.)

Re:Absorbs AND Releases? (1)

WrongSizeGlass (838941) | more than 2 years ago | (#36979658)

Can I patent this thermodynamics stuff?

You can try, but I think the fact that the Universe exists just might be considered prior art.

Re:Absorbs AND Releases? (1, Insightful)

Anonymous Coward | more than 2 years ago | (#36979662)

No, not just like "matter", you fucking moron.

Since when did, say, a piece of concrete not release stored heat until the ambient temperature drops below a set point? Because, last I checked, normal materials release heat the minute the ambient temperature drops below the material temperature.

Honestly, with your low UID, I would've expected you to have functional reading comprehension skills. Maybe it's time to see a doctor about your old age dementia, there, old timer.

Re:Absorbs AND Releases? (2)

Raenex (947668) | more than 2 years ago | (#36980370)

Can I patent this thermodynamics stuff?

No, but you can get modded up for posting a shallow comment that applies to the headline only. Maybe if you weren't rushing to get the first post in you could have at least read the summary.

Heat, Not Temperature (2)

Doc Ruby (173196) | more than 2 years ago | (#36980482)

These Phase Change Materials are different from other matter. They absorb heat without changing their temperature.

So as the heat energy increases in a room - say, when sunlight shines in a window, or hot air circulates in - the energy is absorbed by the PCM instead of heating the regular matter in the room. So the energy increases, but the room's temperature doesn't. Instead, the heat energy changes the phase of the PCM. So work is done by the energy, just not work that increases temperature. Which means a room can "heat up", but doesn't feel like it to people (or other things made of matter) inside.

Later, as heat leaves the rest of the room (outside temperature drops as Sun goes down, cold air enters, etc), the PCM phase changes back, releasing the heat energy into the rest of the room. The temperature of the room stays the same again, though there's less heat - the lower heat content of the PCM merely "relaxes" the phase to the lower energy phase.

It's exactly like the way that ice stays at 32F (0C) in your drink in a 70F room or a 90F beach, even as it absorbs heat from the drink and the surrounding air. So the drink and everything in the glass stays at about 32F (given convection in the drink around the ice), even though the total heat is increasing in there. The ice gradually changes phase, which consumes energy without its temperature rising. Until eventually it's 32F water when the phase change is complete. Then the temperature rises, because there's no phase change consuming energy.

Yes, it's thermodynamics. But unless you can invent a PCM that harnesses thermodynamics, you can't patent it. Unless maybe you're just a patent troll. They're immune to thermodynamics laws, and probably legal laws, too.

Re:Heat, Not Temperature (1)

WindBourne (631190) | more than 2 years ago | (#36980756)

First off, ALL mater absorbs energy while undergoing a phase change. During that time, they are not changing temperatures. Once the phase change is done, then the temp will change.
Likewise, phase change is not a big deal. The issue is that it moves from solid to liquid. At time of changing to liquid, it will have to interact with another material to stay stick around or be in small micro bubbles that are attached.

Re:Heat, Not Temperature (1)

Doc Ruby (173196) | more than 2 years ago | (#36981032)

Not all matter undergoes phase changes while heated, and not all in the same way. Very rare is matter that can have its phase-change temperature tuned to a required point the way this stuff. Also unusual is the phase change holding such a large amount of heat per mass, especially without deforming the way this stuff doesn't.

This stuff is revolutionary.

Where is TFA? (1)

jhoegl (638955) | more than 2 years ago | (#36979552)

Link no worky. False link.... Its a TRAP!

I'm calling it... (0)

Anonymous Coward | more than 2 years ago | (#36979560)

..."adobe". [Dr. Evil pinkie]

Re:I'm calling it... (1)

AlienIntelligence (1184493) | more than 2 years ago | (#36982500)

..."adobe". [Dr. Evil pinkie]

lol,

But you know, I'm sure most people are wondering why you are
talking about Photoshop, Illustrator, Flash, et al.

Lot of them thar young-uns don't even know who Austin Powers is,
and the reference is whoosh.

I know... I thought it inconceivable too, until I realized it recently
before my eyes. "You've NEVER seen those movies? REALLY?"

-AI

It's all about the state change... (2)

elkto (558121) | more than 2 years ago | (#36979664)

Its all about bringing the state change into a temperature zone that can utilized, and it has to be cheap.
Damp Magnesium Sulfate always worked for us.

large storage of energy, huh? (1)

Tanman (90298) | more than 2 years ago | (#36979674)

How does it react to common hazards ... such as fire? Boom? If it goes up like a pine tree then it isn't very good, imo.

Re:large storage of energy, huh? (3, Funny)

WindBourne (631190) | more than 2 years ago | (#36979796)

Not a problem. It is from China. They will be using asbestos to handle this.

No credibility (3, Insightful)

MrQuacker (1938262) | more than 2 years ago | (#36979688)

After all the articles about plagiarized and outright made up research in Chinese universities, I have to take every "discovery" they announce with huge skepticism.

Re:No credibility (1)

Anonymous Coward | more than 2 years ago | (#36979870)

The research is nothing new. Frisby Technologies Inc. has been in business since 1989 to commercialize encapsulated PCMs, including pouring beads of PCM into wallboard and using them in gloves and sleeping bags. Papers have been written since as far back as 1980 on the subject of using PCMS to moderate building temperatures.

Re:No credibility (0)

Anonymous Coward | more than 2 years ago | (#36982872)

they were not tunable.

Re:No credibility (1)

Big_Breaker (190457) | more than 2 years ago | (#36984632)

yes they are. Most PCMs are a mix of materials that phase change at different temperatures. Change the mix, change the phase change temperature. As long as the materials are not terribly different, the phase change occurs mostly at the average of the individual chemicals. Look up eutectic salts

Re:No credibility (1)

icebike (68054) | more than 2 years ago | (#36980016)

Considering that such materials were commonly sold for residential housing use back in the 70s and 80s, I'd say you were spot on.

2001: http://www.toolbase.org/Technology-Inventory/HVAC/phase-change-materials [toolbase.org]
1999: http://freespace.virgin.net/m.eckert/index.htm [virgin.net]
1998: http://www.sciencedirect.com/science/article/pii/S0040603198003682 [sciencedirect.com]
1997: http://www.sciencedirect.com/science/article/pii/S0196890496000726 [sciencedirect.com]

Re:No credibility (1)

geekoid (135745) | more than 2 years ago | (#36987210)

Your point?

They aren't claiming to invent PCMs. the made a new one..which looks lighter and more efficient. Of course, I do share the skepticism. Science studies and claims from China have dubious history.

Re:No credibility (0)

Anonymous Coward | more than 2 years ago | (#36980752)

From Kickstarter.com in MAY:

http://www.kickstarter.com/projects/705847536/coffee-joulies-your-coffee-just-right?ref=card

=====

Coffee Joulies will now be made in the USA :-)

Hey Kickstarters, thanks for checking out our project! We have spent the last nine months developing Coffee Joulies to create the perfect coffee drinking experience for you, and now we need your help to get them produced.

Coffee Joulies work with your coffee to achieve two goals. First, they absorb extra thermal energy in your coffee when it’s served too hot, cooling it down to a drinkable temperature three times faster than normal. Next, they release that stored energy back into your coffee keeping it in the right temperature range twice as long.

Re:No credibility (0)

Anonymous Coward | more than 2 years ago | (#36983872)

Seeing as the chinese make up roughly 20% of the world population and that you are concluding based on what less then 0.0001% of the university activities of the chinese that they are all likely plagiarizing, why not just do it propper and assume that all research in the world is likely plagiarized?

Limited utility (3, Interesting)

rgmoore (133276) | more than 2 years ago | (#36979732)

Note that this kind of material only works to increase the heat capacity of the building, so it will only work when the temperature fluctuates across the phase change temperature over the course of the day. You'll still need a heater if it gets cold and stays cold and an air conditioner if it gets hot and stays hot. The big benefit is that the heat capacity only applies across a narrow temperature range, so it's relatively easy to maintain that temperature passively.

Re:Limited utility (1)

icebike (68054) | more than 2 years ago | (#36980084)

You are presuming that heat would be extracted from the house during the day. But that is not always necessary, and as you suggest, not very efficient.

An external solar collector working at temperatures much higher than would be comfortable is actually more efficient. Roof mounted collection, and underground storage may be able to collect enough in summer to cover a month or two of fall heating. With such a setup, you can pick a phase change material based on its storage capacity, and be less constrained by picking one that has its phase change in the human comfort zone.

 

Re:Limited utility (4, Informative)

sjames (1099) | more than 2 years ago | (#36980386)

It has limits, but it can save a LOT of energy. In some environments such as a desert, the average temperature is quite nice, but unfortunately it swings from freezing to over 100, so you need a good thermal mass to enjoy that average.

In other cases, the average temperature will not be comfortable, but a thermal mass can still save energy. For example when heating is needed, you can run a heatpump during the warmest part of the day when it runs more efficiently and rely on the mass during the coldest part.

All that said, thermal mass is nothing new, but the phase change at a useful temperature is an improvement on it.

Re:Limited utility (1)

MarcQuadra (129430) | more than 2 years ago | (#36985860)

Not just the desert. I live in the northeast US, temperature fluctuations in the spring and fall can be 30+ degrees in a matter of hours. If I packed my walls with this stuff set to phase-change at 65F, I could probably go until December before turning on the heating system. In the summer, it would probably totally negate the need for air conditioning (not that I have it anyway), since nights tend to be below 65 even when days are in the 90s.

The big question I have in terms of practical use in a retrofit revolves around mold mitigation and the dew point. If my walls are 65F when it hits 90 out, they'll start condensing water, which isn't good for homes.

Re:Limited utility (1)

sjames (1099) | more than 2 years ago | (#36988852)

The condensation is a good point. I don't know just what would be best, but something would have to be done about it.

It might be best to use it as a standalone thermal mass rather than building it into the walls. Then the box that holds it can have a proper condensation drain like an air conditioner. That negates some of the advantages, but it might still be useful.

The important part is the phase change (4, Informative)

Relic of the Future (118669) | more than 2 years ago | (#36979770)

Yes, quick-but-not-entirely-wrong posters, everything absorbs and releases heat. The only reason this is interesting is because of the "PCM" part. If you actually recall your high-school physics, as heat is absorbed by an object, its temperature rises, UNTIL it reaches a phase transition; then the temperature stays constant until the phase change is complete. You probably did this with ice and water. The temperature of a chunk of ice starts below 32, increasing linearly with time, then it stops right at 32 and stays there until all the ice was melted, when it begins increasing linearly again.

This is useful for maintaining a consistent temperature inside when the outside temperature is bouncing above and below the temperature of the phase change (say, between day-time and night-time) rather than always needing to heat when it's cold and cool when it's hot. The PCM "building material absorbs and releases heat" automatically, in theory lowering your energy bills.

The neat thing--and yes, this IS neat--is a) this material is tunable; you can set the phase transition temperature at time of manufacture and b) it doesn't turn into a liquid, but rather changes between two different solid phases, which is nice for things like, you know, walls, that you'd like to stay solid.

And you were all so excited by this idea when Wozniak was pushing it in 2007; he'd latched onto a certain species of wood whose sap underwent a phase change at 72 degrees. Build a house out of that, and it will tend to keep the inside temperature at a Woz-friendly 72 degrees.

Re:The important part is the phase change (1)

dotancohen (1015143) | more than 2 years ago | (#36983762)

The temperature of a chunk of ice starts below 32, increasing linearly with time, then it stops right at 32 and stays there until all the ice was melted, when it begins increasing linearly again.

32? Water freezes at 0. Next you're going to try to pull me leg and tell me that it boils at 212, right?

Re:The important part is the phase change (1)

nitehawk214 (222219) | more than 2 years ago | (#36986578)

The temperature of a chunk of ice starts below 32, increasing linearly with time, then it stops right at 32 and stays there until all the ice was melted, when it begins increasing linearly again.

32? Water freezes at 0. Next you're going to try to pull me leg and tell me that it boils at 212, right?

Nope, 373.15.

stone walls and clay (1)

koan (80826) | more than 2 years ago | (#36979788)

for thousands of years.

I wonder how much the material out gasses...

Re:stone walls and clay (0)

Anonymous Coward | more than 2 years ago | (#36980054)

I wonder how much the material out gasses...

That's the real question. Especially considering this was developed in China where it's "Who cares if it gives you cancer, lets sell it!"

Re:stone walls and clay (1)

White Flame (1074973) | more than 2 years ago | (#36982360)

Also, adobe. I know in certain places in Mexico, many of the older adobe homes don't even bother with AC, while the newer ones can't keep up with the heat.

Re:stone walls and clay (1)

dotancohen (1015143) | more than 2 years ago | (#36983812)

Also, adobe. I know in certain places in Mexico, many of the older adobe homes don't even bother with AC, while the newer ones can't keep up with the heat.

The BSA is on their way to Mexico now, thanks. Never mention Adobe.

Years ago Kurt Vonnegut predicted (0)

Anonymous Coward | more than 2 years ago | (#36980068)

Ice Nine

Microscopic Layers (0)

Anonymous Coward | more than 2 years ago | (#36980244)

Microscopic sprayed on layer will have microscopic heat storage capacity.

Re:Microscopic Layers (0)

Anonymous Coward | more than 2 years ago | (#36980324)

Uh, no? Dewar jars with thin layers of silver really hold in the heat. How are you so stupid?

Re:Microscopic Layers (2)

Doc Ruby (173196) | more than 2 years ago | (#36981016)

This material stores the heat in its phase changing mass' heat capacity. That's nothing like a Dewar jar. How are you so stupid? Easy: you're an Anonymous Coward.

Re:Microscopic Layers (0)

Anonymous Coward | more than 2 years ago | (#36983868)

This material stores the heat in its phase changing mass' heat capacity.

Well, duh, everyone knows capacitance is proportional to surface area. A large thin layer is perfect.

Re:Microscopic Layers (1)

Doc Ruby (173196) | more than 2 years ago | (#36983994)

Except rooms don't have a large surface area. And electrons all have the same charge, so they're stored on the surface of conductors. A "heat capacitor" like this stores heat throughout its volume, and should thicken walls/ceiling to store enough to keep room temperature constant. Its area:volume ration should be large enough to transfer heat to/from room/storage quickly, but that's all that surface area matters.

And keep your "duh" to yourself, Anonymous Coward. You're wrong, and haven't earned the privilege of being condescending.

Re:Microscopic Layers (0)

Anonymous Coward | more than 2 years ago | (#36991260)

And you are easily trolled.

Re:Microscopic Layers (1)

Doc Ruby (173196) | more than 2 years ago | (#36992632)

And you're nothing but a stupid troll. Who cares? I love telling stupid people they're stupid, and why. This time I got to think through the implications of a "heat capacitor". Just because you jerked off on yourself to my answer says nothing about me, and only really bad things about you. Duh.

Re:Microscopic Layers (0)

Anonymous Coward | more than 2 years ago | (#36993244)

This time I got to think through the implications of a "heat capacitor".

I'm glad you were able to amuse that small brain of yours for a while with the implications of that, but meanwhile those of us with a modicum of intelligence know without even thinking that thermal energy is a property of mass, i.e. volume, whereas capacitance scales with surface area (for complicated reasons which I doubt I could explain to you, but for your simple purposes it's good enough to say that "electrons are stored on the surface" - which is a side effect of the true cause, not the cause itself, but like I said, it was just good enough for you to make the connection between capacitance and surface area).

Missing link (0)

Anonymous Coward | more than 2 years ago | (#36980478)

Is there a link to the story? The link in the summary doesn't seem to work.

Nanomechanics (1)

Doc Ruby (173196) | more than 2 years ago | (#36980504)

This material is consuming heat energy to perform the work of dis/organizing its molecules without its temperature increasing. That sounds like a (maybe just nearly) perfect nanomachine powered by heat. If the mechanical work can be powered by heat to do useful matter movement, like microfluidics or even nanoassembly, we might have found a device that can use our too-abundant waste energy (heat) for some of our most useful tasks: chemical manufacturing. Maybe even nanocomputing, pushing molecular rods or fluid transistors.

Any way you look at this stuff it's exciting. Revolutionary. If it's cheap and nontoxic, the whole world could pivot on this stuff the way it did on the steam engine.

Its called stone (1)

Osgeld (1900440) | more than 2 years ago | (#36980704)

welcome to thousands of years ago

Re:Its called stone (0)

Anonymous Coward | more than 2 years ago | (#36981690)

It's called wood. The sap goes through a phase change. I find phase changes in stone to be a bit stuffy for my tastes.

Re:Its called stone (0)

Anonymous Coward | more than 2 years ago | (#36981716)

I find your mom to be a bit stuffy for my tastes, but once you warm her up a bit she goes through a phase change.

Re:Its called stone (0)

Anonymous Coward | more than 2 years ago | (#36984722)

*thumbs up* first thing I thought was "well, my good old solid brick house does this since about a century" (which is aprox when it was build ;)) ... cool during summer days, warm in the colder night and in winter (to be fair, with the help of some 15cm of styrofoam ... but it also worked fairly well prior to that).

U. Nottingham at China? WTF? (0)

Anonymous Coward | more than 2 years ago | (#36981420)

Since when did this international campusing became the vogue?

U. California Los Angels at Shanghai anyone?

Re:U. Nottingham at China? WTF? (1)

slew (2918) | more than 2 years ago | (#36981844)

Since when did this international campusing became the vogue?

U. California Los Angels at Shanghai anyone?

Universities have been setting up international campuses and research centers for quite a while now... Unfortunatly the UC system is broke (as it depends on the State of California for funding) so you won't be seeing a UC-S campus anytime soon, but NYU [nyu.edu] (a private university) is taking the plunge in china [chinadaily.com.cn]...

There is a BASF product on the market for years! (0)

Anonymous Coward | more than 2 years ago | (#36982648)

http://www.micronal.de/portal/basf/ien/dt.jsp

You can buy mortar, cement, bricks and similar stuff with this stuff in it for years now, so this is hardly news. But it is a great material:
Essentially, you can create a building that behaves like a heavy building in summer (eg. only very slowly heating up after a cool night)
and like a light building in winter. (quickly heating up after reducing the temperature at night to reduce energy loss)

The material absorbs very little heat below a set temperature (e.g. 24C) and then suddenly requires great amounts of energy to heat up
any further.

Invented before, and commercially available (1)

Wdi (142463) | more than 2 years ago | (#36983248)

How is this "invention" different from the established product BASF Micronal which has been available for a couple of years?

http://www.basf.com/group/corporate/en/brand/MICRONAL_PCM

Re:Invented before, and commercially available (1)

mdsolar (1045926) | more than 2 years ago | (#36984172)

I suppose it is the non-deformable and tunable aspects that are novel.

Quantitatively? (1)

Dr. Hok (702268) | more than 2 years ago | (#36983262)

This looks all quite well and promising, but there are no numbers. I wonder how much more heat capacity this material has wrt, say, brick or water.

Yeah, I know, Infinite! It's a phase transition where the temperature doesn't rise at all with heat added. Or rather, close to infinite (sorry, my fingers ache as I write this, but I hope you get the idea). I remember measuring spikes in Cp and Cv for hours and hours in undergraduate physics lab, and plotting it out on millimeter grid paper with a pencil. Ah, those were the days...

Where was I? Yes. How much more heat can this material take without heating up? Does it keep the temperature at 20C instead of 35C? Or at 20C instead of 21C? I know it depends on various factors like amount of material, size of room etc., but an example would be great.

Re:Quantitatively? (1)

sgt scrub (869860) | more than 2 years ago | (#36984988)

Oh man. I was on a rant then looked up to see your post. I hate when that happens.

That is nice that they discovered... material? It would help if they released some data showing things like maximum potential heat retention, temperature resistance, release rates, etc... Is it like glass, marble, copper, a vacuum? I mean wtf good is, "it stores heat and releases it later"?

Re:Quantitatively? (1)

ImprovOmega (744717) | more than 2 years ago | (#36987292)

Ice will keep liquid water at 0 degrees centigrade at standard pressure for temperatures from 0.1C to 5,000,000C - it's just a question of "How long?". I imagine it's the same with this material. What is the phase change enthalpy and how much material is there = how long it maintains that temperature and how long a "reset" takes.

And another... (0)

Anonymous Coward | more than 2 years ago | (#36984628)

There's a story [technologyreview.com] about National Gypsum out of North Carolina having this stuff back in 2/4/2010. So, this is not new. My guess is, the Chinese stole it.

Gypsum (1)

LeadSongDog (1120683) | more than 2 years ago | (#36988912)

That is why gypsum drywall is used, right? As a fire tries to heat it, the captive water is evolved out as steam. With some luck, it slows the fire's spread long enough that you get out of the building.

paint on top of paint (1)

hesaigo999ca (786966) | more than 2 years ago | (#36984826)

After i finished spray painting my sky scraper with all my solar cell paint to catch all the light and heat ....now i can spray paint another coat on top of it, and have duplicate layer technology that will allow for me to have more heat or less, and still give me my electricity?

Do the math. (1)

ResidentSourcerer (1011469) | more than 2 years ago | (#36985546)

Suppose that this material had a phase change specific heat comparable to the liquid/solid change of water. 330 kJ/kg.

By comparison the specific heat of water is only 4 kJ/kg

Let's consider a house 20x40 feet with R30 walls and an R40 ceiling.

It has 120 linear feet of wall x 8 feet high so it has roughly 1000 square feet of wall. At R30 that's 33 btu//hr/F. The ceiling is 800 square feet at R40 so it's 20 btu/hr/F. So our cute windowless box takes 53 btu/hr/F

In 12 hours it will use 640 btu/F. I chose 12, figuring that the temperature would spend half the day being too hot, and half being too cold. Hmm. Two kilograms per degree F. It would take 160 kg of water to do the same thing with a 2 degree F fluctuation in temperature

If we assume a desert climate that averages nice, but has a 20F on either side of nice, now it takes 40 Kg of this wonder material.

Now that specific heat is too high by a factor of 3 or so.

Now we are up to 120 Kg.

And the heat/cooling load of a typical building is evenly split by the insulated walls and the windows. (Windows are normally 10% of floor area, but have 10-15 times the heat transmission unless you go high tech.)

So that adds a factor of 2. 240 kg.

In a heating environment air changes are ususallly responsible for another factor of 2 in heating. This can be reduced considerably by using a heat recovery ventilator. But lets be passive.

500 kg of wonder stuff.

I started out this note to show that it was unreasonable to do this. It looks quite feasible.

A sheet of gypock is, what, a kg/square foot. A house typically is 2 rooms thick, so it has 2000 square feet of wall gyprock, and 800 square feet of ceiling gyprock. So if roughly 20% of the gyprock mix were wonder stuff, it could handle a 20 degree excusrion on either side of nice.

However, it would make for an awfully thick layer of paint.

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