4 ms·

Amazing. And remember, this stellarator is our "Plan B". The main effort is in the alternative method, the Tokamak (in ITER).

by kensai 10y ago

threeseed 10y ago
And Plan C is ARC/SPARC out of MIT which I like because it is taking more of a startup approach and addresses issues such as financial return on investment, maintenance etc. https://www.youtube.com/channel/UCMFsHceLUJNkXMiCMFNnvkA https://www.youtube.com/channel/UCMFsHceLUJNkXMiCMFNnvkA
- andrewflnr 10y ago
  Between stellarators working out and these guys, I'd actually put ITER down as plan C, not A.
  - mtgx 10y ago
    Isn't plan A what Lockheed Martin is building? At least they made it sound like they were the closest to real fusion. http://www.lockheedmartin.com/us/products/compact-fusion.html http://www.lockheedmartin.com/us/products/compact-fusion.htm...
    - chillydawg 10y ago
      Yeah, but Lockheed could just be running a scam to fleece the US govt out of millions in research grants and tax credits. Obviously it's a huge bet that could pay out $lol if it succeeds, but I suspect it's more of an accounting trick than serious R&D.
      - XorNot 10y ago
        They're not running a scam, but they don't have the results to be in more then the research curiousity stage. Keep in mind too, the W-7 isn't designed to be net energy positive either whereas ITER is.
        drjesusphd 10y ago
        Are you aware of ANY results at all?
      - sfifs 10y ago
        I believe that they are self funding it
        chillydawg 10y ago
        I expect there are significant tax credits available for investing in that kind of research. In the UK there certainly are. You can characterise an awful lot of software development as R&D and write the cost off as research and claim a tax credit, which can be very substantial. The last place I worked was running this "scam" and offset it's dev budget by millions of pounds a year.
    - drjesusphd 10y ago
      Tokamaks have already achieved "real fusion" over 20 years ago, and have gotten close to breakeven.
    - DennisP 10y ago
      From what I've seen, most fusion researchers are skeptical. Lockheed hasn't revealed much detail, and their people aren't leaders in the field. They also have a long way to go; when they made their big announcement they were running on about 100 watts of power. By comparison, MIT's C-Mod uses as much power, briefly, as the entire city of Cambridge. Lockheed claims that fast iteration will make for fast progress, but they're not the only fusion startup taking that approach. Others include General Fusion, Helion, and Tri Alpha. And Tri Alpha, at least, gets a lot of respect for openly sharing experimental data in papers and conferences.
      - zamalek 10y ago
        Exactly, they are going down as my plan A. I've got very little confidence in the likes of ITER because, while they are doing amazing work, they are getting fusion-never funding.
dom0 10y ago
Although Tokamaks aren't really all that suitable as a power plant, because they cannot ever operate continuously. A stellarator can.
- drjesusphd 10y ago
  Can you provide a reference for that claim about tokamaks?
  - dom0 10y ago
    Due to the DC current flowing in the plasma inducing the plasma's magnetic field it has to be operated in some kind of pulsed mode for operation. See eg. https://www.euronuclear.org/info/encyclopedia/t/tokamak.htm https://www.euronuclear.org/info/encyclopedia/t/tokamak.htm Whereas the Stellarator has no DC current flowing in the plasma and can operate continuously with no pulsing/ripples.
    - drjesusphd 10y ago
      Current need not be generated inductively, it can arise naturally ("bootstrap current"). There have already been experiments with as much as 85% of the current coming from this mechanism. As far as I know, there's no reason to absolutely rule out a bootrap fraction close to unity. If you have information that does rule this out, I would like to hear it, since I hear this claim repeated often. Edit: there's also lower-hybrid current drive. This combined with boostrap means that ITER may be able to operate at steady-state.

Amazing. And remember, this stellarator is our "Plan B". The main effort is in the alternative method, the Tokamak (in ITER).

by kensai 10y ago

Amazing. And remember, this stellarator is our "Plan B". The main effort is in the alternative method, the Tokamak (in ITER).

threeseed 10y ago

And Plan C is ARC/SPARC out of MIT which I like because it is taking more of a startup approach and addresses issues such as financial return on investment, maintenance etc. https://www.youtube.com/channel/UCMFsHceLUJNkXMiCMFNnvkA https://www.youtube.com/channel/UCMFsHceLUJNkXMiCMFNnvkA

andrewflnr 10y ago
Between stellarators working out and these guys, I'd actually put ITER down as plan C, not A.
- mtgx 10y ago
  Isn't plan A what Lockheed Martin is building? At least they made it sound like they were the closest to real fusion. http://www.lockheedmartin.com/us/products/compact-fusion.html http://www.lockheedmartin.com/us/products/compact-fusion.htm...
  - chillydawg 10y ago
    Yeah, but Lockheed could just be running a scam to fleece the US govt out of millions in research grants and tax credits. Obviously it's a huge bet that could pay out $lol if it succeeds, but I suspect it's more of an accounting trick than serious R&D.
    - XorNot 10y ago
      They're not running a scam, but they don't have the results to be in more then the research curiousity stage. Keep in mind too, the W-7 isn't designed to be net energy positive either whereas ITER is.
      - drjesusphd 10y ago
        Are you aware of ANY results at all?
    - sfifs 10y ago
      I believe that they are self funding it
      - chillydawg 10y ago
        I expect there are significant tax credits available for investing in that kind of research. In the UK there certainly are. You can characterise an awful lot of software development as R&D and write the cost off as research and claim a tax credit, which can be very substantial. The last place I worked was running this "scam" and offset it's dev budget by millions of pounds a year.
  - drjesusphd 10y ago
    Tokamaks have already achieved "real fusion" over 20 years ago, and have gotten close to breakeven.
  - DennisP 10y ago
    From what I've seen, most fusion researchers are skeptical. Lockheed hasn't revealed much detail, and their people aren't leaders in the field. They also have a long way to go; when they made their big announcement they were running on about 100 watts of power. By comparison, MIT's C-Mod uses as much power, briefly, as the entire city of Cambridge. Lockheed claims that fast iteration will make for fast progress, but they're not the only fusion startup taking that approach. Others include General Fusion, Helion, and Tri Alpha. And Tri Alpha, at least, gets a lot of respect for openly sharing experimental data in papers and conferences.
    - zamalek 10y ago
      Exactly, they are going down as my plan A. I've got very little confidence in the likes of ITER because, while they are doing amazing work, they are getting fusion-never funding.

dom0 10y ago

Although Tokamaks aren't really all that suitable as a power plant, because they cannot ever operate continuously. A stellarator can.

drjesusphd 10y ago
Can you provide a reference for that claim about tokamaks?
- dom0 10y ago
  Due to the DC current flowing in the plasma inducing the plasma's magnetic field it has to be operated in some kind of pulsed mode for operation. See eg. https://www.euronuclear.org/info/encyclopedia/t/tokamak.htm https://www.euronuclear.org/info/encyclopedia/t/tokamak.htm Whereas the Stellarator has no DC current flowing in the plasma and can operate continuously with no pulsing/ripples.
  - drjesusphd 10y ago
    Current need not be generated inductively, it can arise naturally ("bootstrap current"). There have already been experiments with as much as 85% of the current coming from this mechanism. As far as I know, there's no reason to absolutely rule out a bootrap fraction close to unity. If you have information that does rule this out, I would like to hear it, since I hear this claim repeated often. Edit: there's also lower-hybrid current drive. This combined with boostrap means that ITER may be able to operate at steady-state.