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I think that the title is a bit click-baity as the Q ratio reported for the experiment is still 0.00005 (0.005 percent quoting the article). Still an impressiv

I think that the title is a bit click-baity as the Q ratio reported for the experiment is still 0.00005 (0.005 percent quoting the article). Still an impressive achievement, but would've not used the word "groundbreaking" IMHO. I believe that in the context of nuclear fusion that word is often used to allude at reaching an energy surplus out of the reaction.

AreYouSirius 5y ago
chii 5y ago
This video details some of the ways that nuclear fusion energy reporting gets done (both media, but also the industry) : https://youtu.be/LJ4W1g-6JiY https://youtu.be/LJ4W1g-6JiY We are not near a viable fusion reactor yet. Not close.
- yetihehe 5y ago
  Yep. > "HB11 Energy’s research demonstrated that its hydrogen-boron energy technology is now four orders of magnitude away from achieving net energy gain when catalyzed by a laser," reads the press release. "This is many orders of magnitude higher than those reported by any other fusion company, most of which have not generated any reaction despite billions of dollars invested in the field. > HB11 claims is a "world-first 'material' number of fusion reactions by a private company So they have a result which is 10x better than they thought will be, but still way lower than stellarator etc.
  - eightails 5y ago
    And still lower than other laser systems using inertial confinement. If I'm reading NIF's recent paper right, they're claiming Q_a of above ~1.4, or Q = ~0.28 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8791836/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8791836/ Edit: Wikipedia suggests that they were using a different method to calculate Q, only measuring the power input to plasma vs output from fusion, not including system losses. So that figure is probably not directly comparable. > the NIF used ~477 MJ of electrical energy to get ~1.8 MJ of energy into the target to create ~1.3 MJ of fusion energy https://en.wikipedia.org/wiki/National_Ignition_Facility#Burning_plasma_achieved https://en.wikipedia.org/wiki/National_Ignition_Facility#Bur...
  - neltnerb 5y ago
    The spin is also a bit weird... suggesting that their experimental results were ten times better than their theory predicted doesn't exactly lend a ton of confidence to me in their theory. It's interesting, at that scale. But just imagine if someone designing a power plant said that their reactor generated 10x the power calculated. Neat, at that scale. But very strong spin.
- adrianN 5y ago
  That depends on what you mean by "close" and "viable", imo. We know that tokamaks will work if we build them big enough. So it's essentially a matter of dumping sufficient billions into large construction projects, i.e. ITER and DEMO. There are of course some open engineering questions, but afaik, they mostly concern economic viability, e.g. durability of materials involved.
  - apendleton 5y ago
    Big enough, or high-enough field strength. For a given power density, I think required radius scales inversely with the fourth power of the field strength, or something along those lines. ITER was designed when niobium-tin superconductors where the best available, which will limit their field strength to around 13T, but newer HTS magnets should allow some of the upstarts to achieve comparable power densities with much smaller reactors, which should help with at least the economic concerns (durability is still a big concern, though).
    - ncmncm 5y ago
      That just transfers the problem from plasma density to reactor-wall area. "Durability is still a big concern" translates to "but it doesn't help, in the end."
      - DennisP 5y ago
        CFS has an interesting design for that, too. MIT demonstrated joints in REBCO tape that don't introduce significant resistance. By putting these joints in the coils, CFS has a design that will let them open up the reactor and replace the inner wall annually. The inner wall will be 3D-printed, and immersed in a pool of molten salt that functions as coolant and breeding blanket.
  - hutzlibu 5y ago
    "We know that tokamaks will work if we build them big enough. " I think we know that they will work, once they actually work. And the main important question remains, if they will also work economically.
- apendleton 5y ago
  This video gets posted lately every time anyone posts any fusion news lately. It's not a bad video, but I think the point everyone is trying to make is like, "we're not even close, we're orders of magnitude away!", and that's true, but I think maybe a bit misleading. Since fusion experiments began in earnest in the mid-20th century, we've improved in terms of Q by about four orders of magnitude, and the pace of improvement was pretty steady through about the mid-90s, when ITER started to suck all the air (funding) out of the room. Commercial viability is probably somewhere between Q=10 and Q=30, depending who you ask and what specific technology you're talking about, and the best we've done so far is around Q=0.7. So... four orders of magnitude so far, and between one and two still to go. And finally ITER has some competition that could get progress back on track. It's a big lift, but not, like, impossibly or unattainably large.
  - VaxWithSex 5y ago
    As the video states.
  - ncmncm 5y ago
    Q=10, for the Q in typical use, would have no chance of commercial viability. More precisely, it would have substantially less commercial viability than fission, which today lacks it. If we got to Q=1000, we would have viability that might match fission. Viability better than fission is not possible with hot-neutron fusion. Thus, hot-neutron fusion is a dead end. It might be that things learned chasing hot-neutron fusion will turn out to be useful for something else, such as aneutronic fusion. But work on aneutronic fusion, itself, would be overwhelmingly more useful. Very little work is being done on aneutronic fusion.
    - danaris 5y ago
      ....but if I'm understanding the article, and comments here from others more knowledgeable than me, this development is, in fact, work being done on aneutronic fusion.
      - ncmncm 5y ago
- willis936 5y ago
  She conflates ICF and MCF. There are numerous reasons to be pessimistic about ICF. MCF is quite close to triple product performance of a burning plasma, where self-heating becomes dominant. There is a financial hurdle going from a research device to a nuclear machine capable of burning plasma. People are doing it right now though. https://twitter.com/jb_fusion/status/1506964692627034118 https://twitter.com/jb_fusion/status/1506964692627034118
- DennisP 5y ago
  That video makes it sound like we're far away, because we need tokamak output to be about a hundred times better than we've achieved. What it ignores is that tokamak output is highly nonlinear. It scales with the square of plasma volume, and the fourth power of magnetic field strength. Double the field, 16X the output. These scaling laws are very well established at this point. The plasma volume scaling is why ITER is so big. But after ITER was designed, people invented REBCO superconducting tape, which can support much stronger magnetic fields and is commercially available. Using those fields, CFS is building their SPARC reactor, which will get ITER-level output (Qplasma=10) from a reactor half the size of JET, which was built in four years. (Three years for the building, one year for the reactor inside.) If that goes well, the next step would be build their ARC reactor, which will be the same size as JET and get commercial-level output. (Some of the alternate designs also have great scaling in theory, but we don't understand their plasma physics as well so it's harder to predict how they'll turn out.)
deleted 5y ago
[deleted]
nine_k 5y ago
It maybe groundbreaking in the sense that it breaks new scientific ground. Sadly, not suggesting to break new industrial ground.
- marcyb5st 5y ago
  Perhaps, but in that case I would have phrased with something similar to: "New approach to Nuclear Fusion using PW lasers shows promise". Sorry, my new year resolution is to try to pay more attention to this kind of click-bait. Once you start paying attention you see that 1) it is actually everywhere, 2) that since you now notice it is really annoying like being in a room where everyone is screaming, and 3) you can't unsee it :( .

AreYouSirius 5y ago

chii 5y ago

This video details some of the ways that nuclear fusion energy reporting gets done (both media, but also the industry) : https://youtu.be/LJ4W1g-6JiY https://youtu.be/LJ4W1g-6JiY We are not near a viable fusion reactor yet. Not close.

yetihehe 5y ago
Yep. > "HB11 Energy’s research demonstrated that its hydrogen-boron energy technology is now four orders of magnitude away from achieving net energy gain when catalyzed by a laser," reads the press release. "This is many orders of magnitude higher than those reported by any other fusion company, most of which have not generated any reaction despite billions of dollars invested in the field. > HB11 claims is a "world-first 'material' number of fusion reactions by a private company So they have a result which is 10x better than they thought will be, but still way lower than stellarator etc.
- eightails 5y ago
  And still lower than other laser systems using inertial confinement. If I'm reading NIF's recent paper right, they're claiming Q_a of above ~1.4, or Q = ~0.28 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8791836/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8791836/ Edit: Wikipedia suggests that they were using a different method to calculate Q, only measuring the power input to plasma vs output from fusion, not including system losses. So that figure is probably not directly comparable. > the NIF used ~477 MJ of electrical energy to get ~1.8 MJ of energy into the target to create ~1.3 MJ of fusion energy https://en.wikipedia.org/wiki/National_Ignition_Facility#Burning_plasma_achieved https://en.wikipedia.org/wiki/National_Ignition_Facility#Bur...
- neltnerb 5y ago
  The spin is also a bit weird... suggesting that their experimental results were ten times better than their theory predicted doesn't exactly lend a ton of confidence to me in their theory. It's interesting, at that scale. But just imagine if someone designing a power plant said that their reactor generated 10x the power calculated. Neat, at that scale. But very strong spin.
adrianN 5y ago
That depends on what you mean by "close" and "viable", imo. We know that tokamaks will work if we build them big enough. So it's essentially a matter of dumping sufficient billions into large construction projects, i.e. ITER and DEMO. There are of course some open engineering questions, but afaik, they mostly concern economic viability, e.g. durability of materials involved.
- apendleton 5y ago
  Big enough, or high-enough field strength. For a given power density, I think required radius scales inversely with the fourth power of the field strength, or something along those lines. ITER was designed when niobium-tin superconductors where the best available, which will limit their field strength to around 13T, but newer HTS magnets should allow some of the upstarts to achieve comparable power densities with much smaller reactors, which should help with at least the economic concerns (durability is still a big concern, though).
  - ncmncm 5y ago
    That just transfers the problem from plasma density to reactor-wall area. "Durability is still a big concern" translates to "but it doesn't help, in the end."
    - DennisP 5y ago
      CFS has an interesting design for that, too. MIT demonstrated joints in REBCO tape that don't introduce significant resistance. By putting these joints in the coils, CFS has a design that will let them open up the reactor and replace the inner wall annually. The inner wall will be 3D-printed, and immersed in a pool of molten salt that functions as coolant and breeding blanket.
- hutzlibu 5y ago
  "We know that tokamaks will work if we build them big enough. " I think we know that they will work, once they actually work. And the main important question remains, if they will also work economically.
apendleton 5y ago
This video gets posted lately every time anyone posts any fusion news lately. It's not a bad video, but I think the point everyone is trying to make is like, "we're not even close, we're orders of magnitude away!", and that's true, but I think maybe a bit misleading. Since fusion experiments began in earnest in the mid-20th century, we've improved in terms of Q by about four orders of magnitude, and the pace of improvement was pretty steady through about the mid-90s, when ITER started to suck all the air (funding) out of the room. Commercial viability is probably somewhere between Q=10 and Q=30, depending who you ask and what specific technology you're talking about, and the best we've done so far is around Q=0.7. So... four orders of magnitude so far, and between one and two still to go. And finally ITER has some competition that could get progress back on track. It's a big lift, but not, like, impossibly or unattainably large.
- VaxWithSex 5y ago
  As the video states.
- ncmncm 5y ago
  Q=10, for the Q in typical use, would have no chance of commercial viability. More precisely, it would have substantially less commercial viability than fission, which today lacks it. If we got to Q=1000, we would have viability that might match fission. Viability better than fission is not possible with hot-neutron fusion. Thus, hot-neutron fusion is a dead end. It might be that things learned chasing hot-neutron fusion will turn out to be useful for something else, such as aneutronic fusion. But work on aneutronic fusion, itself, would be overwhelmingly more useful. Very little work is being done on aneutronic fusion.
  - danaris 5y ago
    ....but if I'm understanding the article, and comments here from others more knowledgeable than me, this development is, in fact, work being done on aneutronic fusion.
    - ncmncm 5y ago
willis936 5y ago
She conflates ICF and MCF. There are numerous reasons to be pessimistic about ICF. MCF is quite close to triple product performance of a burning plasma, where self-heating becomes dominant. There is a financial hurdle going from a research device to a nuclear machine capable of burning plasma. People are doing it right now though. https://twitter.com/jb_fusion/status/1506964692627034118 https://twitter.com/jb_fusion/status/1506964692627034118
DennisP 5y ago
That video makes it sound like we're far away, because we need tokamak output to be about a hundred times better than we've achieved. What it ignores is that tokamak output is highly nonlinear. It scales with the square of plasma volume, and the fourth power of magnetic field strength. Double the field, 16X the output. These scaling laws are very well established at this point. The plasma volume scaling is why ITER is so big. But after ITER was designed, people invented REBCO superconducting tape, which can support much stronger magnetic fields and is commercially available. Using those fields, CFS is building their SPARC reactor, which will get ITER-level output (Qplasma=10) from a reactor half the size of JET, which was built in four years. (Three years for the building, one year for the reactor inside.) If that goes well, the next step would be build their ARC reactor, which will be the same size as JET and get commercial-level output. (Some of the alternate designs also have great scaling in theory, but we don't understand their plasma physics as well so it's harder to predict how they'll turn out.)

deleted 5y ago

[deleted]

nine_k 5y ago

It maybe groundbreaking in the sense that it breaks new scientific ground. Sadly, not suggesting to break new industrial ground.

marcyb5st 5y ago
Perhaps, but in that case I would have phrased with something similar to: "New approach to Nuclear Fusion using PW lasers shows promise". Sorry, my new year resolution is to try to pay more attention to this kind of click-bait. Once you start paying attention you see that 1) it is actually everywhere, 2) that since you now notice it is really annoying like being in a room where everyone is screaming, and 3) you can't unsee it :( .