22 votes

Successful second round of experiments with Wendelstein 7-X

10 comments

  1. [4]
    spctrvl
    Link
    Are stellarators capable of providing a net power gain yet, like Tokamaks?

    Are stellarators capable of providing a net power gain yet, like Tokamaks?

    2 votes
    1. [3]
      SunSpotter
      Link Parent
      Has there been a verified case of a Tokamak actually providing a net power gain yet? Near as I understand they were simply the leading candidate in an effort to create the first net positive...

      Has there been a verified case of a Tokamak actually providing a net power gain yet? Near as I understand they were simply the leading candidate in an effort to create the first net positive fusion reactor. I did a quick search just to make sure and nothing came up either.

      I do know that ITER is supposed to produce a theoretical net gain, but that won't come online for quite a while.

      5 votes
      1. [2]
        spctrvl
        Link Parent
        Yeah I did some research myself and I am not entirely sure where I got the impression that tokamaks had already achieved break even. I knew that it had been achieved, but apparently only at the...

        Yeah I did some research myself and I am not entirely sure where I got the impression that tokamaks had already achieved break even. I knew that it had been achieved, but apparently only at the NIF so far, which uses inertial confinement. My bad.

        Regardless, we do still know how to build tokamaks with net power gain, and I was wondering if we're in a similar situation with stellarators.

        4 votes
        1. Amarok
          Link Parent
          We're not - in fact we're not even ready to try yet. Wendelstein is not a functional reactor per se - it's a testbed for proving out better plasma confinement concepts. All the plasma is generated...
          • Exemplary

          We're not - in fact we're not even ready to try yet. Wendelstein is not a functional reactor per se - it's a testbed for proving out better plasma confinement concepts. All the plasma is generated externally and injected so they can play with it, not at all like a functional reactor. Presuming it is successful we'd use what we learn to build the first real stellarator-based fusion reactor. Basically, W7x exists so we can shake out the flaws and figure out the best methods and materials to use when we finally do want to build a stellarator for power gain.

          The plasma confinement is the chief hurdle to fusion. We just can't keep long-lived plasmas running inside a reactor chamber yet, and that's the key to power generation. W7x is designed in a crazy, hyper-complicated fashion, by supercomputers and evolutionary algorithms rather than humans, to solve that problem. There's a 10 minute video here that explores the insane design used in its plasma systems.

          In the long run I expect stellarators to rather embarrassingly out-perform the entire class of tokamak designs. They'll be a hell of a lot more expensive to build and maintain, though - probably suited to small numbers of large-footprint grid-backing power plants in major cities. They'll also require a lot of engineers and expertise, so there's a fancy workforce to build as well.

          3 votes
  2. [6]
    mb3077
    (edited )
    Link
    From what I understand they are creating a mini torus shaped 'sun' suspended in a vacuum and getting the 'solar' energy from it? That is beyond cool. Edit: What's even cooler is that the rings...

    From what I understand they are creating a mini torus shaped 'sun' suspended in a vacuum and getting the 'solar' energy from it?

    That is beyond cool.

    Edit: What's even cooler is that the rings around the torus that twist the plasma aren't even circular!
    Imagine how hard it is to calculate the exact shape of each ring down to a millimeter in order to twist the flowing plasma in the most efficient way. It just blows my mind.

    1 vote
    1. [2]
      Amarok
      Link Parent
      Heh. Calling fusion 'putting the sun in a bottle' is selling it short. W7x has temperatures five times hotter than those found in the core of our sun. Kinda boggles the mind. The hottest and...

      Heh. Calling fusion 'putting the sun in a bottle' is selling it short. W7x has temperatures five times hotter than those found in the core of our sun. Kinda boggles the mind.

      The hottest and coldest things in the solar system are right here on Earth. :)

      4 votes
      1. nothis
        Link Parent
        Fact of the day for me, thanks!

        The hottest and coldest things in the solar system are right here on Earth. :)

        Fact of the day for me, thanks!

    2. [2]
      moocow1452
      Link Parent
      I swear to God when I was planning out a SciFi setting, I was going to have the space ship reactor core contain a microstar that it could draw power from, but it seemed unrealistic without gravity...

      I swear to God when I was planning out a SciFi setting, I was going to have the space ship reactor core contain a microstar that it could draw power from, but it seemed unrealistic without gravity manipulation. Shows what I know.

      2 votes
      1. mb3077
        Link Parent
        I guess life does imitate art

        I guess life does imitate art

    3. poopfeast6969
      Link Parent
      Even weirder is that the superconducting electromagnets that keep it suspended have to be cooled to extremely low temperatures. That kind of temperature differential can only exist because it's...

      Even weirder is that the superconducting electromagnets that keep it suspended have to be cooled to extremely low temperatures. That kind of temperature differential can only exist because it's almost a vacuum inside.

      1 vote