The Other Kind of Fusion – General Fusion

When it comes to nuclear fusion size matters.
When it comes to nuclear fusion size matters.

Recent news with regards to nuclear fusion research has not been good:

Yet, just as D-Wave was mostly off the radar with regards to quantum computing, there is another Vancouver based high tech venture that could similarly upset fusion research.

The hot fusion plasma ball up in the sky, when compared to the general fusion challenge down here on earth, is really, really big; It generates an enormous amount of pressure at its core, creating the kind of critical density that assists in sustaining the fusion reaction. So just heating a plasma to the Sun's core temperature (about 16 million K) will not suffice, we have to do about ten times more than that in order to compensate for the lack of gravitational pressure. It shouldn't be surprising that designing a reactor chamber that can hold the hottest thing in our solar system poses a significant engineering challenge.

On the other hand, the idea of tackling the second parameter, the plasma's pressure, in a controllable manner, was generally regarded as technically impossible (not counting NIF like implosion scenarios that more mimic the runaway implosion of a H-bomb, which is why they are interesting to the military).

This common wisdom held until General Fusion entered the fray and made the case that advances in electronics and process control opened up the possibility to tackle the density side of the fusion equation.  And then they built this:

Screen Shot 2013-06-02 at 2.12.23 PM
A device that would fit nicely into the engine room of a spaceship and not look out of place on a SciFi set.

This device is following the age-old engineering adage that if you want compression you use a piston, and if you want large compression you use a large piston which focuses all the energy into a tiny space.  The trick is to be able to do this in such a precise fashion that you can coordinate it with the injection of fuel gas along a central axis, so that you can get a succession of pulsed fusion ignitions with each coordinated firing of the pneumatic pistons.

As with most fusion reactor schemes the envisioned reactor will be fairly compact.
As with most fusion reactor schemes, the envisioned reactor will be fairly compact.

When I first heard about this concept, I thought it was completely off the wall, but the math checks out and there have been other experiments to confirm the viability of this approach.

This device may be testing the limits of mechanical engineering, but if it can create the condition it aims for, then our current understanding of plasma and nuclear physics clearly indicates that it will result in fusion.

The interior of the reactor chamber will have to be cooled with liquid lead. Despite this high energy density, the overall footprint of just the reactor itself is fairly compact, no bigger than the typical dimensions of a commercial nuclear fission reactor. If this design pans out, these reactors could be used to retrofit existing nuclear power stations with a fusion core, converting them to a much cleaner energy source that does not come with the risk of accidentally triggering an uncontrollable nuclear chain-reaction.

The timeline for bringing this to the market is aggressive.  If General Fusion delivers on it, there will be a commercial fusion offering available before ITER even opens its doors.

Given that the latter is not even attempting to deliver a commercial ready design yet, the company will be without competition (unless some of the other commercial fusion ventures such as LPP should beat them).

GF Timeline

Fortunately, with this company it won't be hard to decide when and if they manage to deliver on their promises (there won't be any grounds for the kind of academic backlash that D-Wave has to endure). Unlike in the world of fringe science, where even the simple act of measuring (supposedly) substantial energy gain is obfuscated to the point of utter hilarity, once General Fusion achieves energy net gain, there will be little doubt that we entered the dawn of a new energy age.

(SOURCES: General Fusion Web site, GF 2012 progress report)

12 thoughts on “The Other Kind of Fusion – General Fusion

  1. I am worried that there could be military dimensions to achieving hot fusion in this type of high pressure device without a U-235 or P-239 core. This would have weapons proliferation issues.

    Any comments?

    1. Well, there will be a neutron flux, but using this to breed something that can be used for a nuclear weapons program seems very unlikely, conventional means will be much more practical.

      1. Quax,

        I am not an expert in magnetic confinement fusion. I am just thinking that if the various constants were such that one could get a big impulse (explosive size, lets say 1 KT of TNT equivalent) by setting it up just right, it would be a lot faster for the next nefarious actor to make a small fusion bomblet. (As there is no need to refine/concentrate Pu-239 or U-235.)

        1. Ah, now I get it, using this as a bomb design.

          Given that it will be very difficult to make this work as it is, I’d say this is a pretty remote possibility. Would make for cleaner H-bombs though 😉

          Certainly would go a long way to explain this Steve Jurvetson photo 🙂

  2. Interesting if unrealistic timeline. Any technology attempting to beat nuclei into fusion by overwhelming the Coulomb barrier needs special help – not of the human kind.
    Why kick the dead fusion horse? There’s abetter way and only arrogance and pride prevent the people from realizing it.

  3. GreenWin – it seems that many (most?) of your posts have a negative tone to them… Do you seriously believe controlled fusion will not or can not happen?

    1. GreenWin believes in Cold Fusion, so he has a rather special point of view.

      I am tracking questionable things like that on the Fringe side of my blog, where a very active sceptical crowd is mostly busy trying to debunk this.

      Greenwin is one of the brave souls who dearly believes in cold fusion, yet nevertheless ever so often makes an appearance at this sceptics’ den.

      1. Thanks for the background Quax. I do believe man-made fusion is possible but without the need for thermonuclear events attempted by tokamaks and IC-type stunts. Would physicists consider they do not fully understand how the nuclear process works, they would be more open to finding ways to release binding energies and anomalous heat. Why thermally beat nuclei into submission when with proper cajoling, you can get the same result (better, since there is limited ionizing radiation.)

  4. Since this PhysicsWorld article is directly germane to the topic here I have edited for repost. Gents, it does not grieve me to carry the happy news that yet another guv’ment hot fusion program is being downsized to prepare for termination:

    “The Lawrence Livermore National Laboratory (LLNL) in the US has begun laying off around 10% of its 6500-strong workforce in preparation for “challenges” in the lab’s 2014 budget…”

    Administration’s 2014 budget cuts “…will significantly limit our ability to utilize the National Ignition Facility and undermine [our nuclear] stewardship programme”. Oh well, as the nuclear stewardship program benefits DOD, they should probably pay for it, right?

    See gents, the big picture is the slow but sure awakening of the American people and their Congress to the government sanctioned hoax called “hot fusion.” Even DOE’s (AEC) own Assistant Director Dr. Bob Bussard called it “a fraud.” $Billions for research and the taxpayer gets… nuthin. Looks like the hot fusionists have been busted:

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