5 ms·

This seems.. too good to be true? I don't have the Physics chops to untangle the likelihood of this tech and the credibility of the process and its authors, so

This seems.. too good to be true? I don't have the Physics chops to untangle the likelihood of this tech and the credibility of the process and its authors, so I'm hoping the HN crowd will be able to pad out the story behind this. Certainly, from my layperson's perspective, their website isn't exactly encouraging... https://www.hb11.energy/ https://www.hb11.energy/ - ed re: last line - "books and covers, and all that"

saagarjha 7y ago
Not a physicist, but I thought it seemed fishy as well. I’m curious how they plan to sustain a reaction, since their setup didn’t seem to be useful for more than a single shot…
- lab-notes 7y ago
  This reads like a type of ICF which normally has a stream of pellets being fed in after the initial pellet has reached a hot enough temperature to sustain the fusion reaction.
  - londons_explore 7y ago
    I don't think the goal is to sustain the reaction here... I think the goal is to make a pulsed reactor, where you start the reaction on each pellet in turn. You could imagine a laser firing at 1000 pulses per second, and firing a stream of 1000 pellets per second into the reaction vessel that each pulse hits. Pellets could turn out to be the size of a grain of sand.
- tic_tac 7y ago
  At https://www.hb11.energy/our-technology https://www.hb11.energy/our-technology they list a number of papers they've published supporting their approach. On ignoring the H B-11 reaction with high intensity lasers: https://www.nature.com/articles/ncomms3506 https://www.nature.com/articles/ncomms3506 On the reaction avalanche: https://www.cambridge.org/core/journals/laser-and-particle-beams/article/fusion-energy-using-avalanche-increased-boron-reactions-for-blockignition-by-ultrahigh-power-picosecond-laser-pulses/10862E4B3C4AABD09AC8BF21A2E66487 https://www.cambridge.org/core/journals/laser-and-particle-b... On the conversion of alpha particles to electricity: https://www.cambridge.org/core/journals/laser-and-particle-beams/article/road-map-to-clean-energy-using-laser-beam-ignition-of-boronhydrogen-fusion/8BE057DC1BC9E0A588FB3ABAA993078C https://www.cambridge.org/core/journals/laser-and-particle-b...
randallsquared 7y ago
The Hydrogen Boron reaction is real and well-known to be a way to do fusion without lots of stray neutrons. The sticking point has always been that it's more difficult to cause that reaction than deuterium/tritium or deuterium/deuterium.
- jwbwater 7y ago
  So the fusion here is where two protons form an alpha particle? They show a proton hitting B11 and generating two alpha particles and another proton. 1 proton + (5 protons, 6 neutrons) -> 3 * (2 protons, 2 neutrons) https://www.hb11.energy/our-technology https://www.hb11.energy/our-technology
DennisP 7y ago
Check the publications page for the encouraging part. They might be wrong but they're doing real science. I've personally spoken to a fusion scientist who thought they might be on to something. Exponential progress does sometimes have results that seem too good to be true. In this case the progress has been in picosecond lasers, which for a while have been getting ten times more powerful every three years or so. What's great about this is it should be pretty cheap to test. The petawatt lasers only cost tens of millions in the first place, and China is finishing up a 30PW laser which they plan to let other researchers use. If Hora is right then that should be powerful enough. Even more powerful lasers are being planned elsewhere. HB11 isn't the only company working on aneutronic fusion. The largest is TAE (formerly Tri Alpha), with about $700 million invested. There's also Helion and LPP.
- detritus 7y ago
  Thanks to yourself and randallsquared below for your responses - I'd since posting read the following Abstract by the authors, which hinted that the underlying science was viable: https://www.cambridge.org/core/journals/laser-and-particle-beams/article/road-map-to-clean-energy-using-laser-beam-ignition-of-boronhydrogen-fusion/8BE057DC1BC9E0A588FB3ABAA993078C https://www.cambridge.org/core/journals/laser-and-particle-b... , however my only awareness of existing 'laser fusion facilities' was the American National Ignition Facility (https://en.wikipedia.org/wiki/National_Ignition_Facility https://en.wikipedia.org/wiki/National_Ignition_Facility) , which I think I'd always written off as a covert testing facility for weapons that skirted Nuclear Testing limitation treaties.
  - dragonshed 7y ago
    The science is difficult for a layperson (such as myself) to pick apart, but the above-mentioned publications page[0] links directly to at least one paper[1] which contains some promising detail. [0] https://www.hb11.energy/news-and-publications https://www.hb11.energy/news-and-publications [1] https://aca3d9dd-3b9c-446b-8797-0ba1cdb49ccb.filesusr.com/ugd/1f895b_8767a9007788465aa82df205895197cb.pdf https://aca3d9dd-3b9c-446b-8797-0ba1cdb49ccb.filesusr.com/ug...
  - 7y ago
jabl 7y ago
The big problem with H-B11 and other heavier fusion processes is that the energy radiated away as brehmsstrahlung is greater that the energy gain from the fusion. This was worked out by Todd Rider in his 1995 PhD thesis. Yeah, in theory it might be possible to capture the brehmsstrahlung and pump it back into the reactor with sufficiently high efficiency, but we're pretty far away from that. That being said, all these fancy fusion reactor schemes are interesting. Just make them work on boring old D-T fuel first, then lets see if these other fuels are usable, no?
- DennisP 7y ago
  Yes, but Rider based that on various assumptions, and included an appendix on various ways those assumptions might be violated to achieve net power with aneutronic fuels. I think this reactor would qualify, since it doesn't rely on thermal heating.
  - marktangotango 7y ago
    Polywell claimed to circumvent it as well, I was never clear on their basis for that belief. At least Brussard seemed adamant when he was alive.
    - pfdietz 7y ago
      There was no basis for the belief. Read some of the comments in this reddit thread. https://www.reddit.com/r/fusion/comments/dmqgd5/is_the_polywell_fusion_approach_still_under/ https://www.reddit.com/r/fusion/comments/dmqgd5/is_the_polyw...
- Lev1a 7y ago
  > brehmsstrahlung Bremsstrahlung FTFY
  - jabl 7y ago
    Indeed, you're correct. Thanks.
pxhb 7y ago
I can’t tell for sure from the article but I think they are accelerating protons with TNSA (target normal sheath acceleration). I worked in a lab in undergrad that was doing something similar, except with lithium instead of boron. The main challenges that I recall from a decade ago with TNSA are (WARNING: there almost certainly has been progress since a decade ago): -Conversion efficiency of laser energy into ion (proton) kinetic energy -TNSA accelerates mainly the contaminated layer on the back of targets, which may not be a big deal if you are interested in accelerating protons -TNSA protons are not beam like. They do not have a uniform kinetic energy, and they have a wide angular divergence. -Various laser related issues (prepulse, focal spot size/shape). I also anticipate that it will have the same engineering problem as ICF/NIF, in that it will need to continuously replenish targets.
- DennisP 7y ago
  Here's their publications page, if you're interested in looking into it further. https://www.hb11.energy/news-and-publications https://www.hb11.energy/news-and-publications
deleted 7y ago
[deleted]
moron4hire 7y ago
I don't know. I think a really flashy website would be more concerning. This is a serviceable website that gets it's point across without consuming a gig of bandwidth on a video in the header background.
- jwbwater 7y ago
  Agreed, I do not see their "budget" website as sign they lack credibility, I see it as a sign that they are focused on their work.
moneytide1 7y ago
Yeah I've become wary of "scientific breakthrough" articles that never seem to materialize into anything. But ITER uses huge tower cranes and trucks in the thousands of tons of material required to sustain a temperature hotter than the surface of Sol because of their fuel selection. It seems the small player with a new approach that perhaps demands less complexity in their scaled up commercial reactor could win a commissioning contract with a lower bid during late 2020s early 2030s international bidding. "First milestone is demonstrating the reactions, which should be easy." And "chirped pulse laser amplification" is the recent discovery Hora says will make it possible.
- EthanHeilman 7y ago
  As a researcher I really like 'scientific breakthrough" articles where the impact never seems to materialize. It reminds me that technology development works very differently on earth than it does in my imagination. Breakthroughs happen everyday but the road to real impact is longer and more failure prone after you make the breakthrough than before it. - with some exceptions
deleted 7y ago
[deleted]
Accujack 7y ago
Do a google search for "laser induced fission". Generating plasmas with CPA lasers is becoming more common, but isn't widespread yet because the technology is very new. These plasmas can be the source for all kinds of particles and energy in particular forms, so they may have lots and lots of uses. One person in particular is proposing to use a CPA laser to accelerate nuclear decay, to allow radioactive waste to decay faster and become less toxic more quickly. Of course, my own concern would be that being able to induce fission with a table top laser means that the tech may eventually exist to create a fission or fusion bomb without a nuclear trigger....
- grogers 7y ago
  If they succeed in creating a viable p-B11 fusion power plant and that gets developed into a bomb, wouldn't it be a good thing in the sense that it could replace many thousands of fission-based bombs that have huge fallout risk?
superkuh 7y ago
After reading the article and skimming some of the innumberable references (the article is all references) it seems like the unobtanium part of using laser pondermotive force to accelerate blocks high density plasma from solid state is that the laser "contrast ratio" has to be very high. In the paper it cites many failed replication efforts to use this particular laser pondermotive force due to lack of "contrast ratio". I have no idea what "contrast ratio" means, it isn't defined, and isn't in the references. Does anyone know what "contrast ratio" means in terms of high power pulsed lasers? edit: To answer my own question, ref: https://cdn.intechweb.org/pdfs/24813.pdf https://cdn.intechweb.org/pdfs/24813.pdf > the laser pulse contrast ratio (LPCR) is a crucial parameter to take into consideration. Considering the laser pulse intensity temporal profile, the LPCR is the ratio between its maximum (peak intensity) and any fixed delay before it. A low contrast ratio can greatly modify the dynamics of energy coupling between the laser pulse and the initial target by producing a pre-plasma that can change the interaction mechanism. It seems to be how fast the laser turns on, the rate of change of intensity.

saagarjha 7y ago

Not a physicist, but I thought it seemed fishy as well. I’m curious how they plan to sustain a reaction, since their setup didn’t seem to be useful for more than a single shot…

lab-notes 7y ago
This reads like a type of ICF which normally has a stream of pellets being fed in after the initial pellet has reached a hot enough temperature to sustain the fusion reaction.
- londons_explore 7y ago
  I don't think the goal is to sustain the reaction here... I think the goal is to make a pulsed reactor, where you start the reaction on each pellet in turn. You could imagine a laser firing at 1000 pulses per second, and firing a stream of 1000 pellets per second into the reaction vessel that each pulse hits. Pellets could turn out to be the size of a grain of sand.
tic_tac 7y ago
At https://www.hb11.energy/our-technology https://www.hb11.energy/our-technology they list a number of papers they've published supporting their approach. On ignoring the H B-11 reaction with high intensity lasers: https://www.nature.com/articles/ncomms3506 https://www.nature.com/articles/ncomms3506 On the reaction avalanche: https://www.cambridge.org/core/journals/laser-and-particle-beams/article/fusion-energy-using-avalanche-increased-boron-reactions-for-blockignition-by-ultrahigh-power-picosecond-laser-pulses/10862E4B3C4AABD09AC8BF21A2E66487 https://www.cambridge.org/core/journals/laser-and-particle-b... On the conversion of alpha particles to electricity: https://www.cambridge.org/core/journals/laser-and-particle-beams/article/road-map-to-clean-energy-using-laser-beam-ignition-of-boronhydrogen-fusion/8BE057DC1BC9E0A588FB3ABAA993078C https://www.cambridge.org/core/journals/laser-and-particle-b...

randallsquared 7y ago

The Hydrogen Boron reaction is real and well-known to be a way to do fusion without lots of stray neutrons. The sticking point has always been that it's more difficult to cause that reaction than deuterium/tritium or deuterium/deuterium.

jwbwater 7y ago
So the fusion here is where two protons form an alpha particle? They show a proton hitting B11 and generating two alpha particles and another proton. 1 proton + (5 protons, 6 neutrons) -> 3 * (2 protons, 2 neutrons) https://www.hb11.energy/our-technology https://www.hb11.energy/our-technology

DennisP 7y ago

Check the publications page for the encouraging part. They might be wrong but they're doing real science. I've personally spoken to a fusion scientist who thought they might be on to something. Exponential progress does sometimes have results that seem too good to be true. In this case the progress has been in picosecond lasers, which for a while have been getting ten times more powerful every three years or so. What's great about this is it should be pretty cheap to test. The petawatt lasers only cost tens of millions in the first place, and China is finishing up a 30PW laser which they plan to let other researchers use. If Hora is right then that should be powerful enough. Even more powerful lasers are being planned elsewhere. HB11 isn't the only company working on aneutronic fusion. The largest is TAE (formerly Tri Alpha), with about $700 million invested. There's also Helion and LPP.

detritus 7y ago
Thanks to yourself and randallsquared below for your responses - I'd since posting read the following Abstract by the authors, which hinted that the underlying science was viable: https://www.cambridge.org/core/journals/laser-and-particle-beams/article/road-map-to-clean-energy-using-laser-beam-ignition-of-boronhydrogen-fusion/8BE057DC1BC9E0A588FB3ABAA993078C https://www.cambridge.org/core/journals/laser-and-particle-b... , however my only awareness of existing 'laser fusion facilities' was the American National Ignition Facility (https://en.wikipedia.org/wiki/National_Ignition_Facility https://en.wikipedia.org/wiki/National_Ignition_Facility) , which I think I'd always written off as a covert testing facility for weapons that skirted Nuclear Testing limitation treaties.
- dragonshed 7y ago
  The science is difficult for a layperson (such as myself) to pick apart, but the above-mentioned publications page[0] links directly to at least one paper[1] which contains some promising detail. [0] https://www.hb11.energy/news-and-publications https://www.hb11.energy/news-and-publications [1] https://aca3d9dd-3b9c-446b-8797-0ba1cdb49ccb.filesusr.com/ugd/1f895b_8767a9007788465aa82df205895197cb.pdf https://aca3d9dd-3b9c-446b-8797-0ba1cdb49ccb.filesusr.com/ug...
- 7y ago

jabl 7y ago

The big problem with H-B11 and other heavier fusion processes is that the energy radiated away as brehmsstrahlung is greater that the energy gain from the fusion. This was worked out by Todd Rider in his 1995 PhD thesis. Yeah, in theory it might be possible to capture the brehmsstrahlung and pump it back into the reactor with sufficiently high efficiency, but we're pretty far away from that. That being said, all these fancy fusion reactor schemes are interesting. Just make them work on boring old D-T fuel first, then lets see if these other fuels are usable, no?

DennisP 7y ago
Yes, but Rider based that on various assumptions, and included an appendix on various ways those assumptions might be violated to achieve net power with aneutronic fuels. I think this reactor would qualify, since it doesn't rely on thermal heating.
- marktangotango 7y ago
  Polywell claimed to circumvent it as well, I was never clear on their basis for that belief. At least Brussard seemed adamant when he was alive.
  - pfdietz 7y ago
    There was no basis for the belief. Read some of the comments in this reddit thread. https://www.reddit.com/r/fusion/comments/dmqgd5/is_the_polywell_fusion_approach_still_under/ https://www.reddit.com/r/fusion/comments/dmqgd5/is_the_polyw...
Lev1a 7y ago
> brehmsstrahlung Bremsstrahlung FTFY
- jabl 7y ago
  Indeed, you're correct. Thanks.

pxhb 7y ago

I can’t tell for sure from the article but I think they are accelerating protons with TNSA (target normal sheath acceleration). I worked in a lab in undergrad that was doing something similar, except with lithium instead of boron. The main challenges that I recall from a decade ago with TNSA are (WARNING: there almost certainly has been progress since a decade ago): -Conversion efficiency of laser energy into ion (proton) kinetic energy -TNSA accelerates mainly the contaminated layer on the back of targets, which may not be a big deal if you are interested in accelerating protons -TNSA protons are not beam like. They do not have a uniform kinetic energy, and they have a wide angular divergence. -Various laser related issues (prepulse, focal spot size/shape). I also anticipate that it will have the same engineering problem as ICF/NIF, in that it will need to continuously replenish targets.

DennisP 7y ago
Here's their publications page, if you're interested in looking into it further. https://www.hb11.energy/news-and-publications https://www.hb11.energy/news-and-publications

deleted 7y ago

[deleted]

moron4hire 7y ago

I don't know. I think a really flashy website would be more concerning. This is a serviceable website that gets it's point across without consuming a gig of bandwidth on a video in the header background.

jwbwater 7y ago
Agreed, I do not see their "budget" website as sign they lack credibility, I see it as a sign that they are focused on their work.

moneytide1 7y ago

Yeah I've become wary of "scientific breakthrough" articles that never seem to materialize into anything. But ITER uses huge tower cranes and trucks in the thousands of tons of material required to sustain a temperature hotter than the surface of Sol because of their fuel selection. It seems the small player with a new approach that perhaps demands less complexity in their scaled up commercial reactor could win a commissioning contract with a lower bid during late 2020s early 2030s international bidding. "First milestone is demonstrating the reactions, which should be easy." And "chirped pulse laser amplification" is the recent discovery Hora says will make it possible.

EthanHeilman 7y ago
As a researcher I really like 'scientific breakthrough" articles where the impact never seems to materialize. It reminds me that technology development works very differently on earth than it does in my imagination. Breakthroughs happen everyday but the road to real impact is longer and more failure prone after you make the breakthrough than before it. - with some exceptions

deleted 7y ago

[deleted]

Accujack 7y ago

Do a google search for "laser induced fission". Generating plasmas with CPA lasers is becoming more common, but isn't widespread yet because the technology is very new. These plasmas can be the source for all kinds of particles and energy in particular forms, so they may have lots and lots of uses. One person in particular is proposing to use a CPA laser to accelerate nuclear decay, to allow radioactive waste to decay faster and become less toxic more quickly. Of course, my own concern would be that being able to induce fission with a table top laser means that the tech may eventually exist to create a fission or fusion bomb without a nuclear trigger....

grogers 7y ago
If they succeed in creating a viable p-B11 fusion power plant and that gets developed into a bomb, wouldn't it be a good thing in the sense that it could replace many thousands of fission-based bombs that have huge fallout risk?

superkuh 7y ago

After reading the article and skimming some of the innumberable references (the article is all references) it seems like the unobtanium part of using laser pondermotive force to accelerate blocks high density plasma from solid state is that the laser "contrast ratio" has to be very high. In the paper it cites many failed replication efforts to use this particular laser pondermotive force due to lack of "contrast ratio". I have no idea what "contrast ratio" means, it isn't defined, and isn't in the references. Does anyone know what "contrast ratio" means in terms of high power pulsed lasers? edit: To answer my own question, ref: https://cdn.intechweb.org/pdfs/24813.pdf https://cdn.intechweb.org/pdfs/24813.pdf > the laser pulse contrast ratio (LPCR) is a crucial parameter to take into consideration. Considering the laser pulse intensity temporal profile, the LPCR is the ratio between its maximum (peak intensity) and any fixed delay before it. A low contrast ratio can greatly modify the dynamics of energy coupling between the laser pulse and the initial target by producing a pre-plasma that can change the interaction mechanism. It seems to be how fast the laser turns on, the rate of change of intensity.