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What a weird let down that this is actually thousands of kilometers of super advanced super conducting tape, and not the more mundane varieties available at my local hardware store.
Great headline.
You can buy it though:
https://www.bruker.com/zh/products-and-solutions/superconduc...
You can buy it but there’s no listed price lol
Probably too much if I have to ask ha
The price isn't listed because everything is made custom to order. Nobody orders generic HTS tape.
I've heard prices ranging from $500 to $1,500 per kiloAmp-meter depending on order volume and geometry, so a meter of tape with current carrying capacity of 10,000 amps would cost $5,000-15,000.
I have no idea what CFS uses but some fusion designs require current carrying capacity exceeding 150 kA so it gets expensive really fast when a meter of tape costs $75,000+.
That puts the 10000 km at the upper range of 'astronomical'.
If you need it badly enough I'm sure the price is reasonable. As my old boss used to say: better expensive than not for sale.
I've always heard this but when I'm spending millions is when I ask about price the most.
That makes good sense, but if there is no competing product and/or if there is an urgent need the price may not be all that elastic.
For a commodity (say, server hardware or mechanical gear with well understood production processes) you'll probably be able to negotiate to some degree. But for a niche item such as this I'm not sure it would be nearly as effective. It would be interesting to know how many manufacturers of such tape there are and what the spread in pricing is. But usually they are not listed, it's 'call us for pricing' aka we'll see how much we can fleece you for.
The headline relies on our shorthand of “adhesive tape” as “tape.” There is no adhesive in this tape and it’s not holding anything together. “Tape” simply refers to the geometrical shape of the product
Well there's a second double meaning of the "held together" phrase in the headline too, as it's not adhesive properties of the tape but the electromagenetic properties of the superconducting tape that's doing the "holding."
That doesn't work for me. It's not really holding together the reactor as the headline would imply, it's holding the plasma.
Correct. Unidirectional bonding strip is the preferred Star Command terminology for the adhesive material.
YBCO tape - Yttrium barium copper oxide
ReBCO tape - Rare-earth barium copper oxide
We can still make our own x-ray machines with mundane scotch tape for giftwrapping
I knew about this before i saw it on House M.D., but it was still good to see it spread further. It was usually mentioned in the same paragraph as Certs mints making sparks in your mouth.
The title here implies hacky, but this definitely isn't. But next chance you get, go visit a physics or chemistry lab at a top university. I think a lot of people would be surprised by how hacky things often are in academic labs. You'll find nuclear reactors that are built by students as well as equipment built by them. Then remember that physicists and chemists aren't engineers; mechanical, electrical, nor software. I wouldn't be surprised if you found a fusion reactor in an academic lab held together by tape, metaphorical or literal.
I worked at a university magnetic confinement research lab for a few years. It was certainly scrappy but no literal duct tape. What university labs can accomplish on a tight budget is impressive. Literally plucking vacuum pumps out of the trash. I'd do it again if it could pay the bills.
I would actually guess that Engineering in Universities would also be only marginally better. In research and such good enough really does get quite far. Even if you could fabricate the perfect part. Re-using or jury rigging something likely is still done to save time, money and effort.
SPARC (tokamak) : https://en.wikipedia.org/wiki/SPARC_(tokamak)
Damn. I was hoping for a Red Green-designed Mr. Fusion.
Riding high on a 1985 Ford LTD station wagon piloted by Doc Brown with Harold pointing out some obvious omission at just the moment of catastrophic failure.
Title: "Fusion reactor is held together with tape"
Lead: Fusion reactor requires 10000 kilometers of this superconducting tape
Title: "spacex rocket is glued with bubblegum" Lead: 16 thousands of elves must chew resin from the Yggdrasil for 100 years to create a bubblegum that will hold spacex rocket together
You may mean "lede"?
Either I don't understand the reference, or I'm not understood. The "lead" is the first paragraph of the publication.
That's what they're saying. It's spelled "lede": https://www.merriam-webster.com/dictionary/lede
10,000 km? I wonder how many amps that can carry.
(I have occasional daydreams of a global power grid; four of these reactors would have enough superconductor to go around the equator).
ReBCO still isn't practical for grid transmission AFAIK. It needs to be cooled to something like 20 K to achieve high current. That's ~4x warmer than traditional superconductors (~4.5 K) but it's still not "high temperature" by anyone else's standards.
But you wouldn't be able to use it in that application because you can't keep it cool enough.
Tens of kiloAmps.
Wouldn't a superconductor theoretically be able to carry infinite amps? since it has zero resistance? (I=V/R etc)
Not really, at a certain amount of current (how much exactly depends of the shape and material of the superconductor in question) it "quenches", where it abruptly goes back to being a material with non-zero resistance. Since there is usually a ton of current already flowing through the material, this usually leads to damage as the former superconductor heats up rapidly.
See also https://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_...
There is a critical magnetic field at which superconductors stop being superconductive [1]. Generally, a superconductor carrying a lot of current suddenly becoming conductive is a bad thing. This is directly related to the maximum current density in a particular superconducting wire, so you need larger cross sections to increase the current carrying capability.
Nah, but easy misconception. Rearrange it as V=IR and that formula tells you there’s no voltage drop across the superconducting bit regardless of current.
More current produces a stronger magnetic field around the conductor, and superconductors usually have a maximum magnetic field beyond which they stop superconducting.
Take down the world for the low low price of 4 missiles! Sign me up.
How promising is the physics of this thing? The basic claim here is that that, with a better magnet, tokomaks can produce useful power. Is that a valid claim?
How does energy come out? As neutrons? Something with a charge? What's the first wall, the thing the emitted particles hit?
These are the standard fusion reactor questions, and the article avoids all of them. Seeing an article this dumbed down from the IEEE is disappointing.
Yes it's valid. Tokamak scaling is very well established: the output scales with the square of reactor size but the fourth power of magnetic field strength. Double the field, 16X the output. That's why CFS can build reactors much smaller than ITER to achieve basically the same thing.
80% of the energy from D-T fusion is neutron radiation. The CFS plan to deal with it is this:
- Surround the inner war with molten FLiBe salt which functions as both coolant and tritium breeding blanket.
- The inner wall is 3D-printed and replaced annually.
- The magnetic coils are hinged so they can be opened up to replace the inner wall. MIT proved several years ago that they could do this in REBCO tape without adding significant electrical resistance.
This old presentation from MIT's Dennis Whyte goes into more detail: https://www.youtube.com/watch?v=KkpqA8yG9T4
> This old presentation from MIT's Dennis Whyte goes into more detail: https://www.youtube.com/watch?v=KkpqA8yG9T4
Oh, that's fascinating. The tape has fantastic properties. The superconductive layer is only 1μm thick. The superconductor itself doesn't quench at high magnetic field strengths, which is different from most other superconductors. The insulator is stainless steel! Compared to a superconductor, anything with more resistance is an insulator.
His key points are 1) now we can have much stronger magnetic fields, and 2) with stronger magnetic fields, some of the other hard problems, such as plasma instability, go away. Also, this tape is much easier to work with than other superconductors. Not brittle, less damaged by radiation, not too hard to terminate, superconducts below 43K. So some expensive engineering problems also go away.
All this is very encouraging.
ReBCO is a huge boon for magnetic-confinement fusion. The comment from their CEO that "In fact, from a physicist’s standpoint, our machines look kind of boring [...] we could get extremely high performance through the brute force of the magnetic field” hits the nail on the head.
Experiments like DIII-D have spent the last 20-30 years trying to eek out a few dozen percent more performance by fine-tuning the shape of the plasma & the current distribution inside it, etc. Some of the configurations they've tested are right on the edge of instability, requiring high-speed control systems to walk up to (but not over!) the edge of an invisible cliff in parameter space. If we learned anything from Three-Mile-Island and Chernobyl, we do not want that kind of twitchiness in a nuclear context. Sure, the worst-case fallout isn't as bad, but the multi-billion dollar reactor could be crippled for months/years, depending on how things play out. Boring is good, in a nuclear context.
The downside to the use of brute force is literally the forces involved. The original design (a class project) estimated that the structural steel required to hold the coils of a reactor together would run almost $5 billion & account for ~80% of the total cost of the core. (See Table 11 of [0]) This is for a power plant that would deliver ~ 250MW of electricity. The total plant cost would probably be $10-15B, which is not economical. However, they say "there likely exists a better economic optimization of magnetic field strength versus mass for a full power plant." Most likely, that involves reduced field but larger size reactors, which might be slightly more expensive but significantly more powerful. (IIRC, the latest designs for ARC are inching up toward 4 meters major radius.)
I doubt this approach can reach economic breakeven, but I think they have a good shot at exceeding energy breakeven. OTOH, I'm a physicist rather than an engineer, and I work for a competitor, so take my opinion with a grain of salt.
[0] https://library.psfc.mit.edu/catalog/reports/2010/15ja/15ja0...
Empirically derived scaling laws here (5 minute mark for the spark notes, but the whole video is worth watching). This is a lay-consumable presentation. You could spend a grad program reading the papers to build up this understanding from first principles.
I toured a multi-million-dollar electron microscope at ORNL. They had a piece of tissue paper taped to the side. I asked about it, and they said that it was an airflow monitor. It turned out to be more sensitive than some very expensive sensors, according to the tour guide.
> Although “high temperature” might suggest something that could burn you, HTS materials operate in a range of 20 to 77 kelvins (around –200 to –250 °C).
Technically, grabbing a massive object at 20-77K will result in burns.
I think this is very cool research, but I'm almost certainly neither fusion nor fission will be a significant part of the solution.
Fission has already lost the competition, being far too expensive, and not getting any better.
Fusion will take decades to get to production, let alone to being competitive.
Meanwhile, renewables are extremely amenable towards mass manufacturing, mass deployment, and quick iteration, something neither fusion nor fission are good at. We'll ultimately solve the problem by inelegant brute force rather than by a small number of amazingly engineered wonders.
I wish I could flag ieee.org for clickbaiting.
These are the kind of clickbait headlines I enjoy.
Iter will be humiliated in exactly the same way and for exactly the same reasons that the US Governnment's efforts to crack the human genome were humiliated by Venter & Celera moving at a far faster pace. While the smaller, faster, more nimble approaches will race on ahead, Iter will lag badly.
Celera used HGP data but not vice versa, so that's not a fair comparison. Celera's use of shotgun sequencing was an inspired choice, but even in retrospect it wasn't obviously superior to HGP's chain termination. It was high risk high return bet that could well have failed, while HGP made a conservative choice.
Sequencing has two parts of reading and assembling. Shotgun sequencing makes reading easier and assembling harder. Computing infrastructure of 1990s was barely enough to assemble shotgun reads of human genome, and Celera was overly optimistic from its success on fruit fly genome. They were saved by miracles and heroics at the end.
Of course shotgun sequencing is much better now because we have much better computing infrastructure.
Ironically, the US government had the opportunity to fund this project when it comes as still entirely contained at MIT. They didn't, and so the fusion people at MIT spun a startup to be able to receive funding and collaborate with the scientists still at MIT.
So the government (1) could have been at the forefront of this project through funding MIT, (2) its tech and results would be entirely public, (3) we may have already had first plasma with sparc by now because the time it took MIT to accept they were no longer going to receive tokamak levels of funding - and then come up with CFS as a solution to get private funding for work within MITs system