We Will Know In Two Years

[MSimon]

Patents expire after 20 years. I think the IP has now expired. It's taken too long to attempt to make polywell work. None to worry about.

The requirement is sole sourced to Energy/Matter Conversion Corporation (EMC2) who is the original developer of the plasma fusion (polywell) approach and holds the proprietary data rights.

OK. They have data. That is not the same as a patent.

If you measure the heat capacity of iron and keep it to yourself nothing prevents me from measuring it too.

If you have a production process for making paper clips and the data from that production process, nothing prevents me from making paper clips. It might be useful for me to have that production data if I want to raise capital for a paper clip company. It might save me money vice having to develop the data myself. Nothing prevents me from making paper clips.

So what did the solicitation mean? That it would be much less costly for the government to develop the device if they used the folks who already have the data.

For good or ill EMC2 is in a good spot re: experiments and in a not so good spot when it comes to production of Polywells. Some one is going to buy the fifth or thirtieth production Polywell, reverse engineer it, and go into competition unless EMC2 can nail down some important subsidiary patents.

IMO their best bet is to do consulting for a large mfg.

BTW any one bought a new IMSAI computer lately? Being among the first to market without ironclad IP is a very tough situation long term for a small company without mass production experience and tens of billions in capital. Look at the car industry. Is Studebaker still making cars? Is Zenith still making radios? Heck, are they still making computers?

[93143]

The only way I can make sense of it is that the probability is low that the cost of power from a future polywell reactor will be higher than that from a future tokamak reactor, but still lower than that from future alternatives. Considering the high projected costs of tokamak power, even in optimistic scenarios, this statement is true but not very helpful.

If a net-power Polywell is feasible at all, it is likely to be more economical than a tokamak.

How's that? True or not, it's easier to understand this way...

[chrismb]

If both Polywell and tokamak work as they are both envisaged by their most staunch and believing supporters, then Polywell will definitely beat the pants of tokamak - this is a statement even I can say with almost complete confidence. A working Polywell's performance would be incredible.

...Polywell is incredible!

[93143]

All right, I'll try again.

There are three possibilities.

1) Polywell works as advertised, ie: much better than tokamak. I have not assigned a probability to this.

2) Polywell doesn't work. Tokamak is better, because it almost certainly will work. I have not assigned a probability to this.

3) Polywell works, but not as well as advertised. I have not assigned a probability to this either. However, in this case there is a wide range of potential definitions of "works", and it is my somewhat educated opinion that the majority of this range still constitutes 'better than tokamak'. Tokamaks wouldn't have to work a whole lot worse than they do in order to be unfeasible.

Discuss.

[Art Carlson]

If both Polywell and tokamak work as they are both envisaged by their most staunch and believing supporters, then Polywell will definitely beat the pants of tokamak - this is a statement even I can say with almost complete confidence. A working Polywell's performance would be incredible.

...Polywell is incredible!

How about comparing the high-end hopes for polywells to the high-end hopes for tokamaks when tokamaks were in the same stage as polywells are now, i.e. having produced three neutrons? It's easy to be optimistic as long as you are also ignorant.

...Polywell is incredible!

[Art Carlson]

Tokamaks wouldn't have to work a whole lot worse than they do in order to be unfeasible.

That sums it up. Your statement says a good deal about tokamaks (which I wouldn't deny) but not much about polywells.

[TallDave]

How about comparing the high-end hopes for polywells to the high-end hopes for tokamaks when tokamaks were in the same stage as polywells are now, i.e. having produced three neutrons? It's easy to be optimistic as long as you are also ignorant.

True. OTOH, we can say something the tokamakkers could not at that point: it will not cost $20B+ to find out if Polywell works (where "work" means "produce energy at a competitive cost").

Actually, come to think of it, they still can't say that about tokamaks, billions of dollars and neutrons later.

Also, did anyone ever seriously envision burning p-B11 in a tok? My 1950s text seems to rule that out.

[93143]

Tokamaks wouldn't have to work a whole lot worse than they do in order to be unfeasible.

That sums it up. Your statement says a good deal about tokamaks (which I wouldn't deny) but not much about polywells.

Yeah, basically.

Okay, unless there's someone who still doesn't understand what I meant, I think we can consider this issue closed.

...

What was my point again? Oh yes:

if EMC2 can get the transport worked out for Polywell it should be vastly superior to any toroidal system.

This is of course slightly different from the statement we've been arguing about (which was part of my explanation of the above), but hopefully my meaning is fairly clear by now.

The other half of the point I was trying to make is that toroidal magnetic systems and IEC don't mix very well because of the confinement properties of the toroid. The advantages Polywell supposedly has would largely evaporate, in exchange for a lot more trouble than tokamak currently has.

Art, you seemed to more or less agree with this assessment. Is that right?

[gblaze42]

How about comparing the high-end hopes for polywells to the high-end hopes for tokamaks when tokamaks were in the same stage as polywells are now, i.e. having produced three neutrons? It's easy to be optimistic as long as you are also ignorant.

...Polywell is incredible!

I wouldn't call it ignorance, obviously your just being inflammatory, there is still to much yet to be learned about the polywell fusion at this stage, I won't say if it will be successful or not, but going by Dr. Nebel's statements up until now, there is potential.

Now I do not know who you are, but from where I stand Dr. Nebel is the only one working on a real Polywell fusion device, that makes him the expert, he has the data and that trumps theory. I hope you don't mind if I take his word over yours.

[MSimon]

Just to beat a dead horse: toks envision making 10% more tritium than they use with a Lithium blanket neutron to tritium converter. As Art points out that is cutting it rather fine for an unproven total design. It would not be hard to come in with 10% less tritium than they use and there goes the whole shooting match.

For an experimental design you really want to come in at 2X what you hope for in all the critical design parameters. And 5X or 10X is a much more comfortable margin.

[MSimon]

Just to beat a dead horse: toks envision making 10% more tritium than they use with a Lithium blanket neutron to tritium converter. As Art points out that is cutting it rather fine for an unproven total design. It would not be hard to come in with 10% less tritium than they use and there goes the whole shooting match.

For an experimental design you really want to come in at 2X what you hope for in all the critical design parameters. And 5X or 10X is a much more comfortable margin.

The advantage for Polywell is that if it works it scales nicely and it is not too large to begin with so R^3 scaling and B^4 scaling is not too hard to come by. Going to 1 m coils (from .3 m coils) gives you about a 30X power boost. And going to 1 T (from .1T) gives you about a 1E4 power boost. If it produces 1 mW in the current set up you are at 300 W for the improved situation. Going from there to 10 T and you are in the 3 MW range. Once that is accomplished (if it can be) then you are in the "unlimited funds for further development" regime.

[KitemanSA]

How about comparing the high-end hopes for polywells to the high-end hopes for tokamaks when tokamaks were in the same stage as polywells are now, i.e. having produced three neutrons?

Art,
Isn't this just a bid disingenuous? You keep says "3 neutrons" but it was actually ~3 out of the expected ~3, every time they did it. That is a whole different situation. Your statement suggests they got no data. The reality is the data match expectations across the board. I like the sound of the second way a whole lot better!

[icarus]

Msimon:

If it produces 1 mW in the current set up you are at 300 W for the improved situation. Going from there to 10 T and you are in the 3 MW range. Once that is accomplished (if it can be) then you are in the "unlimited funds for further development" regime.

Interesting, and 2G from there with mass-produced 10T superconducting magnet systems, a 10kW fusion device for small properties (e.g in a shipping container out back) could become a reality ... and 3G, mr. fusion in your mack truck?

[TallDave]

300W would be interesting. At that point you could actually take a stab at measuring loss scaling.

[MSimon]

Interesting, and 2G from there with mass-produced 10T superconducting magnet systems, a 10kW fusion device for small properties (e.g in a shipping container out back) could become a reality ... and 3G, mr. fusion in your mack truck?

To get to 2G you may have to solve a very challenging first-wall problem (or maybe Rick and company already have ideas for this). At 10kW I don't see how it can be anything resembling cost-effective.

Dave,

You may have missed it but at high fields there is no first wall problem. Dr. N. first pointed that out about a week or two ago. And I did some calculations and came up with .35T as the transition point for a machine with 2 m diameter coils. Above that the alpha gyroradius is smaller than the coils.

viewtopic.php?p=19276#19276

Rick's estimate was that in a power reactor the alphas would make 1,000 transits before leaving through a cusp.