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I am a strong proponent of Fusion energy and did some work on the subject in undergrad. This is not a major breakthrough, it's a benchmark. A major breakthrou

by iaw 5y ago

I am a strong proponent of Fusion energy and did some work on the subject in undergrad. This is not a major breakthrough, it's a benchmark. A major breakthrough would be materials that could withstand the neutron bombardment longer, the ultimate limiting factor for fusion energy plants after we achieve positive net energy.

bobsmooth 5y ago
Have you heard of General Fusion? They're using liquid metal as both containment and energy extraction. Really cool, they're building a demo plant in the UK.
mikeytown2 5y ago
https://en.wikipedia.org/wiki/Neutron_reflector https://en.wikipedia.org/wiki/Neutron_reflector Doesn't reflectors help a lot here or am I missing something?
- SomeCollegeBro 5y ago
  Probably, but I'd guess that the reflector still absorbs a small percentage of the beam it's reflecting. And at the GW scale I'm sure even a small percentage is enough to absorb a great deal of energy.
mrjangles 5y ago
You will find, especially after reading the comments, that fusion is not about creating electricity (it never will), it is about sparking people's imagination. Many people grew up reading science fiction and there is seriously nothing it the last 50 years that comes close to the amazing breakthroughs in the physical world that happened in the 50 years before that. The idea of fusion is the best thing going right now. You won't be able to have a serious conversation about the pros and cons of fusion power because any serious conversation will always be trampling on people's dreams.
- mcv 5y ago
  If fusion is the best thing right now, that would be incredibly sad, because it barely seems to be making any progress at all. Fortunately we've seen tons of progress in other fields: computing, quantum computing, solar energy, medical, gene therapy. Even superconductors are slowly getting better.
  - mrjangles 5y ago
    Yeah but that stuff just doesn't really tickle the imagination. You won't see that stuff on the cover of an 80's scifi book.
    - liamwire 5y ago
      That first sentence is an entirely subjective take, and one that I disagree with entirely.
  - ludsan 5y ago
    I don't get comments like this. Is there a measure of progress we should be using for this? Not only does this resemble the "where's the flying car I was promised?" complaint but it ignores the very real realities that a lot of progress is measured in increments that have a way of sneaking up on you exponential-style. Solar energy, for instance, was not a huge announcement, but it was a steady trickle of learning curve improvements (https://news.ycombinator.com/item?id=25265819 https://news.ycombinator.com/item?id=25265819) Do you remember ten years ago when nobody had heard of mRNA or CRISPR? Or fifteen years ago when neural networks were a dead end and SVM were all the rage? I'm not saying fusion is the "best thing" or have any insight as to where it might be in the curve of adoption, but it feels weird to be making a race out of fusion with these other technologies.
    - mcv 5y ago
      The comment I responded to held fusion up as an example of something that sparked the imagination. I'm just pointing out that it's a sad example and we have far better and more inspirational examples. mRNA and CRISPR are great examples of that; those are real breakthroughs.
mcv 5y ago
I used to like the idea of fusion energy, but practical application has always seemed to be 40 years in the future, and it's starting to sound more like 60 years now. I hope it will be possible some day, but it's not going to help with out energy needs in our lifetime. (Unless that longevity research is going to pay off, I guess.)
- bsder 5y ago
  > I used to like the idea of fusion energy, but practical application has always seemed to be 40 years in the future, and it's starting to sound more like 60 years now. You have to understand that fusion has been funded at "fusion never" levels for 5 decades now. The amount of money that we poured at the mining engineering that later became "fracking" was larger. Had we funded fusion at the amount we have funded petroleum extraction, we'd have free energy by now. :(
  - credit_guy 5y ago
    Who is "we"? Fracking was funded with private money. It was "conventional" technology, no edge-of-science stuff, so private entrepreneurs could afford it, and the rewards were quick to materialize. Nuclear fusion? There's this urban myth that fusion could have been achieved if only we'd have poured more money into it, but where's the evidence? Plasma modeling requires a lot of computational power. What you have now in your iPhone in your pocket you could not have had for 10 billion dollars back in 1970. How much money were we supposed to put into fusion research? Do you think with lots of money and just a slide rule, you can solve the fusion problem?
    - brutusborn 5y ago
      I think you're mistaken about the government involvement in fracking. Sure, the basic technique may have been developed by private companies, but government supported research expanded it to oil and gas applications. https://thebreakthrough.org/issues/energy/us-government-role-in-shale-gas-fracking-history-a-response-to-our-critics https://thebreakthrough.org/issues/energy/us-government-role...
fouc 5y ago
What I'd like to know is what design or material changes were required to reach this benchmark? The picture of the fusion chamber is still the same torus donut shape as the ones from the 90s.
- iaw 5y ago
  I believe the issue is that the surrounding materials of the torus in the TOKAMAK become highly radioactive due to neutron bombardment and decay accordingly. IIRC, there is some sort of Silicon Carbon based material that need to be economically feasible to manufacture (that can withstand a fair amount of neutron bombardment without crumbling like other materials) before a plant will ever make sense. There may be alternative materials but none of them are cheap enough to build a long-term TOKAMAK even if we could achieve the incremental net power necessary for a power plant.

by iaw 5y ago

bobsmooth 5y ago

Have you heard of General Fusion? They're using liquid metal as both containment and energy extraction. Really cool, they're building a demo plant in the UK.

mikeytown2 5y ago

https://en.wikipedia.org/wiki/Neutron_reflector https://en.wikipedia.org/wiki/Neutron_reflector Doesn't reflectors help a lot here or am I missing something?

SomeCollegeBro 5y ago
Probably, but I'd guess that the reflector still absorbs a small percentage of the beam it's reflecting. And at the GW scale I'm sure even a small percentage is enough to absorb a great deal of energy.

mrjangles 5y ago

You will find, especially after reading the comments, that fusion is not about creating electricity (it never will), it is about sparking people's imagination. Many people grew up reading science fiction and there is seriously nothing it the last 50 years that comes close to the amazing breakthroughs in the physical world that happened in the 50 years before that. The idea of fusion is the best thing going right now. You won't be able to have a serious conversation about the pros and cons of fusion power because any serious conversation will always be trampling on people's dreams.

mcv 5y ago
If fusion is the best thing right now, that would be incredibly sad, because it barely seems to be making any progress at all. Fortunately we've seen tons of progress in other fields: computing, quantum computing, solar energy, medical, gene therapy. Even superconductors are slowly getting better.
- mrjangles 5y ago
  Yeah but that stuff just doesn't really tickle the imagination. You won't see that stuff on the cover of an 80's scifi book.
  - liamwire 5y ago
    That first sentence is an entirely subjective take, and one that I disagree with entirely.
- ludsan 5y ago
  I don't get comments like this. Is there a measure of progress we should be using for this? Not only does this resemble the "where's the flying car I was promised?" complaint but it ignores the very real realities that a lot of progress is measured in increments that have a way of sneaking up on you exponential-style. Solar energy, for instance, was not a huge announcement, but it was a steady trickle of learning curve improvements (https://news.ycombinator.com/item?id=25265819 https://news.ycombinator.com/item?id=25265819) Do you remember ten years ago when nobody had heard of mRNA or CRISPR? Or fifteen years ago when neural networks were a dead end and SVM were all the rage? I'm not saying fusion is the "best thing" or have any insight as to where it might be in the curve of adoption, but it feels weird to be making a race out of fusion with these other technologies.
  - mcv 5y ago
    The comment I responded to held fusion up as an example of something that sparked the imagination. I'm just pointing out that it's a sad example and we have far better and more inspirational examples. mRNA and CRISPR are great examples of that; those are real breakthroughs.

mcv 5y ago

I used to like the idea of fusion energy, but practical application has always seemed to be 40 years in the future, and it's starting to sound more like 60 years now. I hope it will be possible some day, but it's not going to help with out energy needs in our lifetime. (Unless that longevity research is going to pay off, I guess.)

bsder 5y ago
> I used to like the idea of fusion energy, but practical application has always seemed to be 40 years in the future, and it's starting to sound more like 60 years now. You have to understand that fusion has been funded at "fusion never" levels for 5 decades now. The amount of money that we poured at the mining engineering that later became "fracking" was larger. Had we funded fusion at the amount we have funded petroleum extraction, we'd have free energy by now. :(
- credit_guy 5y ago
  Who is "we"? Fracking was funded with private money. It was "conventional" technology, no edge-of-science stuff, so private entrepreneurs could afford it, and the rewards were quick to materialize. Nuclear fusion? There's this urban myth that fusion could have been achieved if only we'd have poured more money into it, but where's the evidence? Plasma modeling requires a lot of computational power. What you have now in your iPhone in your pocket you could not have had for 10 billion dollars back in 1970. How much money were we supposed to put into fusion research? Do you think with lots of money and just a slide rule, you can solve the fusion problem?
  - brutusborn 5y ago
    I think you're mistaken about the government involvement in fracking. Sure, the basic technique may have been developed by private companies, but government supported research expanded it to oil and gas applications. https://thebreakthrough.org/issues/energy/us-government-role-in-shale-gas-fracking-history-a-response-to-our-critics https://thebreakthrough.org/issues/energy/us-government-role...

fouc 5y ago

What I'd like to know is what design or material changes were required to reach this benchmark? The picture of the fusion chamber is still the same torus donut shape as the ones from the 90s.

iaw 5y ago
I believe the issue is that the surrounding materials of the torus in the TOKAMAK become highly radioactive due to neutron bombardment and decay accordingly. IIRC, there is some sort of Silicon Carbon based material that need to be economically feasible to manufacture (that can withstand a fair amount of neutron bombardment without crumbling like other materials) before a plant will ever make sense. There may be alternative materials but none of them are cheap enough to build a long-term TOKAMAK even if we could achieve the incremental net power necessary for a power plant.