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>the way to make fusion generate power more efficiently without changing the underlying technology is to make it bigger Actually there was a front page item on

>the way to make fusion generate power more efficiently without changing the underlying technology is to make it bigger Actually there was a front page item on here a couple of weeks ago showing that there's a new superconductor that can generate a stronger magnetic field, which will allow new, much smaller fusion reactors. So according to the guy from MIT who gave the talk, ITER is already obsolete technology. Having said that, with fusion, it looks like every time they have a breakthrough, they find a new limiting factor when then takes billions to overcome, rinse and repeat. It's amazing in theory but we have yet to achieve a fusion reaction that is energy positive and the path to that is still fraught. In theory with these Lithium neutron blankets you can even create your own fuel (Assuming Deuterim-Tritium reaction) but the hurdles are still insanely high to get something that's actually practical. Also, I believe fission and fusion can be synergistic in that you can have a fission reactor that not only produces energy, but it produces some of the fuel for the fusion.

2OEH8eoCRo0 6y ago
>So according to the guy from MIT who gave the talk, ITER is already obsolete technology. >It's amazing in theory but we have yet to achieve a fusion reaction that is energy positive and the path to that is still fraught. He also said that fusion has a funding issue, not a science or engineering issue. Also- being able to make them smaller mostly solves the funding issue.
- joncrane 6y ago
  Yes, it removes ONE funding obstacle because as the OP I replied to says cost increased with the 4th power of the size, but that just means you move to the next limiting factor: the neutron blanket, designing to be able to swap out the shielding, etc. We are still VERY far away from practical fusion. The fact that we know what the current limiting factors are doesn't mean that once we overcome those hurdles that we'll have a practical solution.
  - jcims 6y ago
    I wonder if that General Fusion design has any benefit here? It’s basically a swirling sphere of molten lead that is injected with a bubble of hydrogen plasma and then a bunch of pistons pump the volume down to collapse the bubble to create fusion conditions. It seems that that the lead might provide neutron shielding and is also the carrier fluid for the excess heat. Who knows if it actually works but the simplicity of the design seems pretty elegant.
    - pfdietz 6y ago
      I don't think GF has a realistic chance of making a workable reactor. They've already given up on the acoustic compression scheme, and the slow compression scheme they are now following has a metal post down the middle of the chamber, unshielded from average neutron fluxes that will, at the center, be orders of magnitude higher than in more conventional reactors.
      - jcims 6y ago
        That’s a bummer, I always liked the idea, sort of like collapsing cavitation bubbles. Lots of energy focused on a very small spot. I could never sort out how the plasma injection would work without some kind of physical tube placing it in the center... guess it didn’t lol.

2OEH8eoCRo0 6y ago

>So according to the guy from MIT who gave the talk, ITER is already obsolete technology. >It's amazing in theory but we have yet to achieve a fusion reaction that is energy positive and the path to that is still fraught. He also said that fusion has a funding issue, not a science or engineering issue. Also- being able to make them smaller mostly solves the funding issue.

joncrane 6y ago
Yes, it removes ONE funding obstacle because as the OP I replied to says cost increased with the 4th power of the size, but that just means you move to the next limiting factor: the neutron blanket, designing to be able to swap out the shielding, etc. We are still VERY far away from practical fusion. The fact that we know what the current limiting factors are doesn't mean that once we overcome those hurdles that we'll have a practical solution.
- jcims 6y ago
  I wonder if that General Fusion design has any benefit here? It’s basically a swirling sphere of molten lead that is injected with a bubble of hydrogen plasma and then a bunch of pistons pump the volume down to collapse the bubble to create fusion conditions. It seems that that the lead might provide neutron shielding and is also the carrier fluid for the excess heat. Who knows if it actually works but the simplicity of the design seems pretty elegant.
  - pfdietz 6y ago
    I don't think GF has a realistic chance of making a workable reactor. They've already given up on the acoustic compression scheme, and the slow compression scheme they are now following has a metal post down the middle of the chamber, unshielded from average neutron fluxes that will, at the center, be orders of magnitude higher than in more conventional reactors.
    - jcims 6y ago
      That’s a bummer, I always liked the idea, sort of like collapsing cavitation bubbles. Lots of energy focused on a very small spot. I could never sort out how the plasma injection would work without some kind of physical tube placing it in the center... guess it didn’t lol.