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Ask Slashdot: How Would Room-Temp Superconductors Affect Us?
Bananatree3 writes "While we have sci-fi visions of room temperature superconductors like in the movie Avatar, the question still remains: How would the discovery of a such a material impact our everyday lives? How would the nature of warfare change? How would the global economy react? What are the cultural pros and cons of such a technological shift?" And just as important, in what contexts would you want to see it first employed?
From a human perspective I am rather fond of living at or around room temperature.
Not really: radiative emission is the only type of cooling you can get in space. Depending how much power you're bleeding off elsewhere on your ship, it could be quite difficult to keep things suitably cool. Especially considering that any part of your ship facing the sun is going to be picking up quite a high thermal load.
The most realistic answer, but not the one you want to hear, is: Nobody really knows.
If history teaches us one thing than it is that we are horrible at predicting the outcomes of anything major. In hindsight, we can "explain" things, but our predictions suck so badly, it's a surprise we haven't given up on the subject. And that's for both experts and non-experts.
Nobody came even close to predicting the impact of computers. Or electricity. People didn't think WW1 would become the slaughterhouse it did. There are refugees around the globe who are living in "temporary" shelters, waiting to return home because the conflict will surely be over any day now. Some of them have been waiting for a decade and more.
The real impact of this technology, as most, will most likely not be anything that anyone today predicts, but something that someone in the future comes up with that nobody thought of before. That includes the inventors. I don't think Graham Bell ever thought that "please turn off your mobile phones" would be a screen shown in these newfangled movie theatres that just came about in his time.
Assorted stuff I do sometimes: Lemuria.org
Is it hell, space isn't cold, it is inert. I seriously wish people would stop thinking this.
The only way heat gets out of things in space is radiative or an infinitely small amount of conductive.
Direct sunlight on a person would burn them in space, likewise heating up metals and components.
Space is actually probably harder to cool things down in simply due to sunlight.
On earth it is pretty easy to have something in shadow and vented so that an incredible amount of heat is exchanged over to the flowing air.
In space, you can only rely on highly-resistant insulators and/or mirrors to get rid of heat unless you liquid cool things. (which is good too since you can then use that heat inside the ship)
100% computational efficiency, 0% heat release
You can't do that. Any non-reversible computation causes an increase in entropy, and reversible computation is not particularly practical. Achieving practical reversible computation would be a leap at least as large as room temperature superconductors.
Finally! A year of moderation! Ready for 2019?
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This is true but one of the great things about a superconductor is that R (and thus the power dissipated) goes to zero. So while it is difficult to dissipate heat in space, you won't be building up heat in the superconductors themselves.
Maglevs comes to mind - you only once load the magnets along the track, and then they will keep the magnetic field forever.
Imagine roadrails along the interstates which keep the cars on track. Also the hover car will suddenly be feasible - as soon as the car moves forward, induction will load the magnets inside the car and let it hover along the supra conducting magnets in the road. You can see the effect already today at some science shows where they have supraconducting maglevs. Zero friction against the track, just air friction left. One can imagine subways with supracontucting tracks, which work with air pressure along the tubes.
Super strong magnets can be build, which you once load with electricity and which then keep the magnetism forever. Construction could get rid of glue and screws, just put the elements together, load the magnets once, and they will keep everything in shape. You could lock your house with magnetic bars, which once locked, keep tight until you unload the electricity from the bars and they open again.
You could store electricity in giant coils instead of chemical cells, making loading and unloading the electricity much faster, and enabling lots of non-constant electricity creators like windwheels and solar panels to work within a giant grid and finally overcome the problem of the electric base load.
Most people think of superconductors as merely a "perfectly efficient" conductor. While this is true, it just scratches the surface of what's possible with superconductors. Using superconductors just to improve efficiency wouldn't be that big a deal by itself. It would improve battery life a little bit, and maybe drop bulk electricity transmission overheads, but not by much, and certainly not immediately. Making most superconductors into high-tensile wire is a non-trivial exercise, even if cooling isn't a problem -- and it will be! Just because a material is discovered that can conduct at "room" temperature isn't helpful for wire outdoors in direct sunlight, or in a hot environment inside high-temperature machinery. Last but not least, superconductors have current and magnetic field limits that increase as they are cooled past the transition temperature. A superconductor with a transition temperature of 26C would probably have only a few limited applications above 20C.
The other uses are more interesting, and often more amenable to thermal control:
The Meissner_effect provides magnetic shielding, which is useful for all sorts of things, like amplifiers, or for protecting sensitive electronics. This is also what causes magnets to levitate above Type 2 superconductors. I assume that a room-temperature superconductor would be Type 2, so levitation would likely be possible.
The London moment could be used in gyroscopes and the like.
Josephson junctions provide all sorts of functions, like ultra-sensitive magnetic field sensors (think hard-drives and MRIs).
Still, all of that is a bit... meh. I mean sure, you get less noise in your now ultra-sensitive amplifier, and electricity will cost 10% less than it would have otherwise in 30 years. Is this life changing? Probably not really.
A much more interesting potential application than all of those combined is Rapid Single Flux Quantum digital circuitry. That stuff makes silicon look like vacuum tubes. Think 100GHz+, self-clocking, 1000x as efficient as CMOS, and manufacturable now, with only the cooling requirement the big down-side. If RSFQ could be made to work at room-temperature (or even near it), you could be looking at a sudden massive leap forward in computer power like never before. For example, with a power draw 1000x lower, it would be possible to stack every chip in a typical computer into a little "cube", with much shorter wire lengths, and hence, latencies. We can't do this now, because that cube would literally melt in seconds form the heat.
The reality-check of all this is that many MRI machines are still cooled by liquid helium, even though superconductors that work at liquid nitrogen temperatures have been available for a while. This tells you a lot about the limitations that might restrict the application of even a hypothetical room-temperature superconductor. For example, ultra-sensitive sensors and RSFQ may not work at all, because the tiny signal quanta may be swamped by the background thermal noise. Similarly, manufacturability of wire and maximum magnetic field strength is a key requirement for a lot of applications, like MRIs and electric motors.
Personally, I suspect that the first room-temperature superconductor will be initially manufacturable in bulk only as a thin-film, so expect the first decade or two to be mostly about improved circuitry and sensors more than anything else. This might be closer than people think. For example, there's a harmless quack who claims to have achieved superconductivity at 28C by manufacturing extremely complex copper-based crystals as a thin layer between two different traditional copper-based superconductors. Assuming for a second that he's onto something, it gives you an idea
"Therefore, a superconductor which would allow us to eliminate the massive amounts of wastage in our electrical infrastructure "
The wastage in the electric infrastructure, on a whole, is about 7% in the US. Speaking of long-distance transmission only, it's closer to 3%
There's not much to fix here, so unless the new superconductor is also free, I don't think you'd see the massive uptake people imagine.
The main upside would be size, not cost. Assuming it has higher current density, piping power into urban areas becomes easier.
The idea that the superconductor won't be adding to the thermal load is all well and good, but it doesn't cope with the problem of heat that comes in from solar radiation or heat generated by other parts of the ship like engines. Furthermore, it becomes a self-reinforcing problem, because being unable to dissipate heat makes the superconductor stop superconducting, which only adds to the problem.
Virg
While these facts may be true on the surface (I haven't actually checked), what you are missing is that most energy production is relatively local, and hence generating capacity is built & run to deal with local maximal demand. Truly efficient long, long distance transmission lines would allow distant capacity to be factored in to the system. Think wind, solar, day vs night etc. There is currently a project (Tres Amigos) designed around a superconducting hub to connect the three major energy networks in the US. In addition there are (at least) plans for several other superconducting trunks, including one to link a number of off shore wind projects. The net efficiency gains for the system as a whole would far exceed the 3-7% mentioned above.
That said, I am partial to local production, as finely grained as possible, to cover the baseline requirements and minimize the opportunity for system-wide failures.
That 7% is transmission loss only. Now consider using it in computing to prevent waste heat from being generated. In radio transmitters for better efficiency. In house wiring. In appliances. In cars. In electric cars. Now you're talking about at least a 50% boost. And that's before you consider using it in electric motors and generators.
If video games influenced behavior the Pac Man generation would be eating pills and running away from their problems.
In practice, you can cool satellites pretty darned far. WMAP is cooled to 90K passively. Planck is cooled to 50K passively. So yes, it is very possible to cool satellites to within the superconductivity range of modern high-temperature superconductors.