Superconductors

Thread Starter

Wendy

Joined Mar 24, 2008
23,798
My impression is they were talking about end use devices. Time will tell. If we ever get room temperature superconducters I suspect transmission lines will be replaced in a few years, but I'm not holding my breath.

The improvements keep coming though, this is the thing.
 

sceadwian

Joined Jun 1, 2009
499
I think the point I was trying to get across Bill was that all the information currently known about 'high' temperature super conductors shows that they're at a boundry, high temperature super conductors don't operate quiet the same was as the simpler cold stuff, they still super conduct but they have that current boundary, if the current density becomes too high it ceases to super conduct, this is... very very bad.

It's not as cut and dry as 'improvements' because with every advanced in higher temperature more is known about the limit of where superconducting will occur and other boundaries (the current density one) crop up. It's a very practical technology, but room temperature super conductors is as much a pipe dream based on current scientific knowledge as anti gravity is.
 

Thread Starter

Wendy

Joined Mar 24, 2008
23,798
That last statement is pretty far out there, since we have no examples of man made variation of gravity. It is right there with superconductors have resistance, since nothing can have zero ohms (that has been said by more than one person on this site).

Superconductors temperatures are slowly creeping up, and they are improving the other parameters as well. A blanket statement that there will never be room temperature is pretty much the same as the argument that people could never go over 60 miles per hour because they couldn't breath, or if man was meant to fly he'd have wings. Fact is, superconductors are still trending upward in temperature after about 50 years sitting still. There is no theoretical or physical reason there can't be room temperature superconductors. There is a theoretical prediction that solid hydrogen will be a room temperature superconductor though.

Next benchmark near as I can tell is CO2 for the cryogenic cooler.

LN2 = 77°K, -196°C
Current hi temp superconductor record = 135°K, -105°C
Dry Ice = -56°C
 
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sceadwian

Joined Jun 1, 2009
499
Lets just throw a little math out there. By the way 135K is -138C not -105

The current record super conductor is HgBa2Ca2Cu3Ox which is 133C
The only paper I can find that references it's actual creation is dated 2002.

Just bellow that at 110K is Bismuth strontium calcium copper oxide, from 1988
Then bellow that was the real game maker (LN2 could be used) Yttrium barium copper oxide, which was back in 1911. Before then were Iron based compounds but I don't see that being developed any further. And bellow that is the pure metalics (no possibility of advancement there)

So from 1911 to current times (2002) we have raised the temperature of copper oxide super conductors by 43 degrees. Averaged out that's right about half a degree per year, with a balance of 205 degrees to make up to 72F, leaving it at 410 years away.

Note however the complete drop of the Iron Oxide super conductor variants... Why? Because they hit a wall that was the limits of the atoms window in which it would super conduct.. Non cuprate based super conductor research will skyrocket once that wall is reached and understood, but this kind of science isn't linear progression is on the losing side of an exponential curve with new materials to base the next generation of science on not currently existing, because all the money is going to the technology that's going to hit the wall in the not too distant future.

I severely doubt that human society can be held stable for the realm of time that would required dedicated learning in order to reach the point where room temperature was a possibility.

Personally I think the current YBCO super conductors are going to be the peak for a commercially applicable super conductor, Most people will go, NO LOOK! The BSCCO stuff is 20 degrees higher!!! So what? It'll still require for practicality sake LN2, it serves man better to develop the existing manufacturing methods for YBCO and devlope the cooling systems to support it. The science out there for game changing temperature stability at a usefully higher temperature doesn't currently exist.
 

Thread Starter

Wendy

Joined Mar 24, 2008
23,798
Look again on your sources again, papers are published weekly, usually more than a paper a day on physorg. While the original discovery has only been slightly improved there are new materials discovered every year.

The ceramic superconductors were discovered in 1986, not 1911. In 1911 only metalics were known, mercury being discovered in 1911, and it was thought they were the theoritical maximum temperatures. I had major hopes we'd be further along 25 years later than we are with the new ceramics.

The new iron based ceramics were discovered in 2006, while they are behind the copper types they are being researched very actively.

The problems with magnetic saturation are being addressed, which goes with the article posted in #19. There is a lot of effort in removing boundry condition flaws in the ceramics that cause a reduction in specs.

http://www.physorg.com/news197901636.html
 
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tom66

Joined May 9, 2009
2,595
Think about this. If we transmitted low voltage DC or AC instead over superconducting wire, we could eliminate two major losses of power. I'm talking about the corona effect and eddy currents in transformers. The corona effect could be avoided because it becomes practical to use lower voltages; perhaps even the same voltage as household mains. And eddy currents, because less or even no transformers are required.

Of course such an upgrade to the electrical transmission system is unlikely to happen in any of our lifetimes due to the enormous cost in doing so (the current system is "good enough") and because superconducting wire which can be used outside (that is in temperatures of up to 60°C) is a long way out, if it's even possible.
 

sceadwian

Joined Jun 1, 2009
499
Transformers will always be required, or some type of switching regulator, unless you're talking about a super conductor multi drop network to local distribution points..... The system complexities of that belittle current system complexities without calculate-able benefits that can be fully cost analyzed. The risks are immense, the benefits little.
 

sceadwian

Joined Jun 1, 2009
499
Who the hell wrote that article?
The transmission loss of superconducting DC (alternating current) power transmission is ten times less than that of superconducting AC power transmission, and thirty times less than the transmission loss of ordinary AC power transmission.
Which is it, DC or alternating?

200 meters is... more than a far cry from say the east coast of the US to the west. 2600 miles. Only 20 thousands times the current achieved distance to go.....

Yes, a step closer indeed.

I'm not doubting the science and the pure research applications, but practicality must rule in the end. Keep in mind even with the best super conducting materials science can currently make, you have to deal with the power through standard conductors at BOTH ends using non super conducting technology, unless you're going to go the route of super conducting distribution system.. the physical connection concerns alone would make a sane person laugh at the idea.


A simple sanity common sense look at things say it's never going to work, but it's great material science research if nothing else.
 

Thread Starter

Wendy

Joined Mar 24, 2008
23,798
Yep, transistors never replaced tubes, they were too noisy.

Cars will never replace whip and buggy, people like horses too much.

Airplanes will never be practical, their too dangerous.

Man will never go to the moon, it's too hard.

All that R&D has a purpose, it isn't for pure science, but nothing will ever come of it.
 

sceadwian

Joined Jun 1, 2009
499
Bill you are completely missing the point... this isn't fundamentally new technology, it's been around almost 100 years now, and we've only come as far as using LN2 as a refrigerant, which took 75 years. It's about efficiency, and as 'bad' as modern power systems are they're not so bad as super conduction for anything but ultra high power long distance would make any kind of sense.. The math for total system cost vs the net benefit of a long haul system DOES NOT COMPUTE, it's cheaper to generate the power locally, and even over the long term the net benefit..

Did you even look at any of the schematics for these wires? It isn't within the realm of current manufacturing or process technique to repair such a wire if it broke!
Fiber optics alone require trained professional and that's a single crystalline substance.

The cars planes and moon crap you're trying to pass off as proof that super conductivity will be the next greatest step of human kind is just that, crap, there's no logic, no sanity, and best of all there is NO science behind it. I'm all for being a dreamer, this is GREAT science no matter how you look at it, but if you believe for even a split second it's going to result in some society altering change for long haul power transfer you're sadly mistaken. I'll be more than happy to place cash bets on the matter at odds to be determined at a later date =)
 

Thread Starter

Wendy

Joined Mar 24, 2008
23,798
OK, some of the examples were lame, but every major innovation was preceded by deniers that sound a lot like your statements. You keep saying it is so because you say it is so, a circular argument at best. The reason so much R&D money is being spend on this is because people smarter than you and I think it will go somewhere, and the payoff is huge.

As for this being an old technology, no. This technology was invented in 1986, it is a complete paradigm shift from what was discovered in the early 20th century. It does not use cooper pairs, indeed, it uses several new mechanisms that are still trying to be understood, new and fundamental. One of the lessons learned is just because you can't do something doesn't make it a natural law.

New classes of materials are still being discovered, along with dramatic (the word applies here) improvements of the "old" technology that was discovered over 20 years ago. Even new mechanisms are being discovered, totally different and separate from others, that all cause superconductivity. The fat lady has far from sung, and the older stuff is starting to come online. This is not theory, it is fact, and if you've read any of the articles I've posted you will find the references.

You keep trying to mix up the century old discoveries and saying they are the same as the new. Not a valid or reasonable argument. Trying focusing on the new stuff, instead of materials that use a different branch of physics.

A schematic for a piece of wire...

I think a coupling would be a more appropriate perspective. The conduit shown in post #28 is a lot more like a coax cable than a wire, complete with a pipe for coolant.

Funny you should mention fiber optic, I did a lot of service (IE, repair) on the machines that fuse two cables together, not to mention I have metrology experience calibrating fiber optic equipment. The process is both simple and cheap, I've trained operators how to do it in 10 minutes. The machines do most of the work, and the cost is pretty reasonable. They do use a coupler of a sort too, though it is for mechanical reinforcement. In this I have decades of experience.

And if you haven't noticed, LN2 is used routinely in industrial processes. At Alcatel the truck came by weekly and filled up our tanks. They were talking about buying local LN2 producing equipment for the factory. Given how much we used it would have had to be pretty beefy, figure about 100 gallons or more a day as a minimum. It is not an exotic material, but an industrial mainstay.

The scammers have started with room temperature superconductors, which is unfortunate. It raises the signal to noise ratio considerably. There have been some materials that required special circumstances that have approached the goal of room temperature, but were extremely impractical because of the extreme pressures that have to be used. Our best hope is probably metallic hydrogen, which is currently in the unobtainium class.

http://www.sciencedirect.com/scienc...=6686075&md5=4dfe98dac323e63bf7c743350a8c482e
 

sceadwian

Joined Jun 1, 2009
499
I'm saying it's so because there is absolute no science of ANY kind that suggests that there are breakthroughs even on the far distance horizon that would make long haul super conductor lines practical in our lifetime, every bit of science I've read in this thread suggests baby steps at best with anything practical still lifetimes away, if it's proven to be possible.

The payoff is huge if and only if it can be made practical, and real.

There's really no point in arguing about it anymore, but I'll try to look you up in 50 years if we're both still kicking around and I'll spot ya the US now equivalent of 100 dollars if I'm wrong =)
 

Thread Starter

Wendy

Joined Mar 24, 2008
23,798
I couldn't read the last article (it would have cost $20), but the transition temp was 260°K (according the the synopsis from Wikipedia). That works out to -13°C. Due to the extreme pressures required it is not practical, but it is interesting.

Basically you are arguing we can't get there because we haven't, and I am arguing with the steady set of improvements we will. Given that millions (billions?) spent on research a lot of people agree with my POV. I'll keep posting the articles showing the steady improvements as they are published, as I have been doing.

This is why I started the thread.
 
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sceadwian

Joined Jun 1, 2009
499
Theoretical improvements in the lab don't mean ANYTHING to practicality in the real world Bill. Take antimater as an example, it's closest to the purest possible energy source we'll ever be able to make, practical production of it on a mass scale won't occur with in the lifespan of any human being on earth. They can produce it reliably for commercial use like PET scanners and for lab use, but widespread use of anti-matter as an energy source isn't practical.

Many experts, however, dispute these claims as being far too optimistic by many orders of magnitude. They point out that in 2004, the annual production of antiprotons at CERN was several picograms at a cost of $20 million. This means to produce 1 gram of antimatter, CERN would need to spend 100 quadrillion dollars and run the antimatter factory for 100 billion years.
I'm not trying to say that room temperature super conductors are really impossible, the everyday practical application of them even if they are discovered tomorrow are dozens if not hundreds or thousands of years away in the progression of the rest of material sciences to make practical.
 

sceadwian

Joined Jun 1, 2009
499
Bill, I do respect you, but you are wrong, only time will tell how, I can not argue that in a momentary conversation.

To strike back at myself I'll refer to Iron Man.
The arc was never cost effective. We knew that before we built it. Arc reactor technology, that's a dead end, right? Maybe. Am I right? We haven't had a breakthrough in that in what? - Thirty years. - That's what they say.
The real world, human civilization marches to the beat of it's own drum.
 

sceadwian

Joined Jun 1, 2009
499
That new property Bill, that's what I'm talking about, science doesn't progress linearly, it progresses in large bursts with a lot of ongoing research in between breakthroughs, superconductors are right at their next boundaries unless some dramatic accidental breakthrough from other sciences sheds new light on the matter it's going to be a long hard road for those that study high temperature superconductors. Science as a whole is progressing quiet nicely, but the individual fields kind of leapfrog against each other as the pure research finds out new details about fields previously not understood.
 

sceadwian

Joined Jun 1, 2009
499
In the short term I think it's useless for semi conductor's as a practical thing, but it's progressing the science, it's still not known in what other types of materials super conductivity can occur. Perhaps a self resonating material will be found that exhibits superconductivity even at lower currents in room temperature materials, which might be useful. Again though, years down the line for even basic research to hole up in.
 
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