The D-D reactions are just to clarifying that fusion actually happens. The neutron count as deuterium nuclei bounce together and overcome the repelling force is important here. That’s how you determine the force of nuclei colliding, and that there’s not just the colliding x-rays produced by bremsstrahlung.

Henning wrote: The D-D reactions are just to clarifying that fusion actually happens.

I understand that — I was just wondering if it was also possible that such reactions could end up at theoretical breakeven. That would seem to me to be a huge validation of the FF approach, even if D-D (and D-T) is not the final intended fuel for a variety of excellent reasons.

Tulse wrote:

The D-D reactions are just to clarifying that fusion actually happens.

I understand that — I was just wondering if it was also possible that such reactions could end up at theoretical breakeven. That would seem to me to be a huge validation of the FF approach, even if D-D (and D-T) is not the final intended fuel for a variety of excellent reasons.

I would venture to guess that the answer would be “no” if “positive power production” means electrical output due to the nature of the products made from D-D fusion versus Boron-Hydrogen. If one just wants to see a general energy out > energy in no matter if it’s heat/x-rays/electrical or whatever…then maybe a series of shots could show that with D-D if instrumented carefully enough in an adiabatic chamber. However, from the pictures I’ve seen so far…I don’t get the impression that such an environment is present so careful heat exchange analysis is not in the cards. I could be wrong of course…I am basing that conclusion on admittedly very limited information.

texaslabrat wrote: If one just wants to see a general energy out > energy in no matter if it’s heat/x-rays/electrical or whatever…

I’ve always understood “breakeven” to be used in this most basic way for all other fusion projects. It’s also my understanding that none of the multi-billion dollar research projects have accomplished this.

then maybe a series of shots could show that with D-D if instrumented carefully enough in an adiabatic chamber. However, from the pictures I’ve seen so far…I don’t get the impression that such an environment is present so careful heat exchange analysis is not in the cards.

That’s my impression as well. I was just curious as to why this wasn’t an initial goal of the research, since being able to accomplish this would go a very long way toward validating the FF approach — it would be doing for a few million dollars what the huge multi-billion research facilities haven’t been able to achieve over several decades. I would think this would be a hugely impressive milestone, and one that might help to free up further investment money and provide legitimacy to the approach. I’m sure the FF folks have thought of this, and I was just wondering as to why it was ruled out as a goal.

Eric, when in the sequence of the eight steps do you anticipate taking pretty pictures of your plasmoids? Also, would you consider those pictures to be material to be released at a conference? Or would you post them immediately on the web?

I understand they are an important part of confirmation of your theoretical understanding of what is happening. But I don’t know if that means you won’t post them immediately.

They will also be great PR of course!

The timeframe strikes me as both aggressive and impressive… net gain by the end of 2010, which is not much more than 13 months.

If you time it right, announce it on New Years Eve…. that will be one year I party like it’s 1999.

It’s no guarantee it works.. but at least we won’t be waiting for a recursive 30 years.

Brian H wrote: The real “net energy” is usable energy, I think, which is either captured heat or electric current (the ideal end result, which FF gets to far more directly than D-D fusion or D-T fusion can). Energy in the form of neutron emissions etc. is pretty much “lost”.

Is there a standard definition of “over unity” for fusion projects? The impression I have always gotten is that the way “breakeven” is typically used is very theoretical, and involves all released energy, whether it would be practical or not to harvest it (and that such things like the Carnot limit and other parasitic energy losses are not considered). It seems to me that the real beauty of the FF approach is that since most of the energy gets captured directly as electricity, it will be very easy to demonstrate practical breakeven, that is, breakeven with all those losses factored in. (By contrast, even if ITER or NIF produce theoretical breakeven, that tells us very little about whether it can be practically turned into more usable power than it consumes, since the actual generation of electricity requires so much additional engineering.)