By what mind trick did you convert science to neutrons? They are not equivalent.chrismb wrote:By what calculation are you making that assessment? Tokamaks, by several orders of magnitude, beat all other neutron-producting devices to the "neutrons/dollar" ratio.tomclarke wrote:What I don't understand is the discrepancy in funding.
...You get more science for your $ ...
ITER Delayed, Scaled Back
Aero
I personally think that Chris' calculation does not make any sense. The number of neutrons produced is not relevant in the big picture. Not even the number of neutrons per USD. What would be relevant is the number of neutrons produced per EVs (?) put into the things. And that ratio does not look to good so far. Given it does not look to great for Polywell yet either. But Tokamaks are pretty much obviously by now a dead end in regards to competitive reactor designs. And anything that does not happen within my lifetime is a dead end to me, period.
So it would make sense to invest in alternatives and look elsewhere.
Polywell has at least a small chance of working. As do the other devices that are being researched. Lets give those a chance!
So it would make sense to invest in alternatives and look elsewhere.
Polywell has at least a small chance of working. As do the other devices that are being researched. Lets give those a chance!
OK - by science I of course don't mean no of neutrons! I mean useful information gained about the behaviour of high energy plasma, behaviour of materials under neutron bombardment, etc, and other issues relevant to possible applications. These include fusion reactors for energy but also other uses of fusion - neutron sources for other purposes etc.tomclarke wrote:
What I don't understand is the discrepancy in funding.
...You get more science for your $ ...
By what calculation are you making that assessment? Tokamaks, by several orders of magnitude, beat all other neutron-producting devices to the "neutrons/dollar" ratio.
I should not really call this science perhaps (go to CERN LHC for that) but applied science.
The ITER money only makes sense if you reckon the aim is a commercial energy source - but this is so far away and expensive, with relatively low applied science benefits, that it is not clear to me it is the right priority.
Often in technology brute force is the wrong approach. I realise that for ITER-syle sustained fusion there are no short cuts and brute force is necessary, but maybe that means other approaches should have more invested in them. Including better fission designs - if the aim is low cost low pollution energy.
PS - just to qualify this a lot of the benefits, bigger magnets, containment walls, etc, etc are applicable to most of the way-out fusion techniques, and other applications, as well as ITER. So it is not that the effort is worth nothing. It is just that these could also be developed with much smaller systems.
I've no idea where this view that tokamaks are a 'dead-end' or are otherwise 'non-viable'. That's crazy talk. They ARE the biggest player and most prolific neutron generator in the game. That's not to say that they won't end up as a dead-end or non-viable, I can and do throw various critique over the most significant issues, but it is way too early to say any such thing at the moment. At least it now has diagnostics and established knowledge over the various issues that tend to lead into instabilities, which were known aspects within 25 years of tokamak research and for which the last 25 have looked at further understanding those and countering them. After 25 years, Polywell doesn't yet even KNOW what its instabilites will be. Why is there a presumption that there won't be any, or if there are any they'll take less than 25 years to fix??
It seems to me that Polywell and tokamak both suffer from people with over-polarised points of view and generally lacking knowledge of the other. Both are active and ARE receiving funding. Polywell cannot currently absorb more funding as the physics haven't yet been well-enough established, the plans just aren't up to a justifiable standard for higher financial inputs nor does there appear to be real scientific understanding to set higher objectives yet, whereas tokamak can absorb this money for plans already estalished as viable routes forward. I draw attention to issues of management of the project's objectives just as I do with Polywell, I treat both with critique to establish the best way forward for both. I do not see that either have been particularly underfunded to date, according to the arguments and supporting evidence. A better management of the outcomes could be implemented in both, I think.
...and if neutrons/$ isn't the primary objective, what the heck is!!!??? What does that mean "science/$" - how many technical papers drilling down into recent diagnostic results have we seen from Polywell?
It seems to me that Polywell and tokamak both suffer from people with over-polarised points of view and generally lacking knowledge of the other. Both are active and ARE receiving funding. Polywell cannot currently absorb more funding as the physics haven't yet been well-enough established, the plans just aren't up to a justifiable standard for higher financial inputs nor does there appear to be real scientific understanding to set higher objectives yet, whereas tokamak can absorb this money for plans already estalished as viable routes forward. I draw attention to issues of management of the project's objectives just as I do with Polywell, I treat both with critique to establish the best way forward for both. I do not see that either have been particularly underfunded to date, according to the arguments and supporting evidence. A better management of the outcomes could be implemented in both, I think.
...and if neutrons/$ isn't the primary objective, what the heck is!!!??? What does that mean "science/$" - how many technical papers drilling down into recent diagnostic results have we seen from Polywell?
Fission designs are going to be of secondary importance to me as long as they:
Can not get an SSTO of the ground (and then without causing the greens to go bonkers)
Can not be built anywhere in the world without people living nearby (and again particularily the greens) going bonkers.
Are still more expensive than coal, again partially because of the greens going bonkers...
So once all these objectives have been achieved, fission will be more interesting to me.
Can not get an SSTO of the ground (and then without causing the greens to go bonkers)
Can not be built anywhere in the world without people living nearby (and again particularily the greens) going bonkers.
Are still more expensive than coal, again partially because of the greens going bonkers...
So once all these objectives have been achieved, fission will be more interesting to me.
Chris -
To be fair it is not number of years funding but number of man-years funding, or number of $ funding, or some metric got from all three. And in that case polywell would not look so well funded. And with science research money those papers from polywell would get published, instead of data languishing in military archives. Maybe if it did polywell would get more theoretical attention and quickly be dismissed as a non-starter, or not.
I think the case against ITER is that the original motivation, as a best long-term energy option, now looks less clear. Not that it won't work, clearly it will, but that it is only suitable for VERY large power generation applications.
If the argument for it is to investigate future low-pollution low-cost power options would the money go to ITER? Or to n+1th generation fission reactors?
I guess I am assuming that what we know of the physics means that trying to make smaller cheaper tokamaks is never going to work - but maybe this is unduly pessimistic?
If the argument for it is to advance high energy physics more generally then a more diverse approach could reasonably be argued to bring more return.
To be fair it is not number of years funding but number of man-years funding, or number of $ funding, or some metric got from all three. And in that case polywell would not look so well funded. And with science research money those papers from polywell would get published, instead of data languishing in military archives. Maybe if it did polywell would get more theoretical attention and quickly be dismissed as a non-starter, or not.
I think the case against ITER is that the original motivation, as a best long-term energy option, now looks less clear. Not that it won't work, clearly it will, but that it is only suitable for VERY large power generation applications.
If the argument for it is to investigate future low-pollution low-cost power options would the money go to ITER? Or to n+1th generation fission reactors?
I guess I am assuming that what we know of the physics means that trying to make smaller cheaper tokamaks is never going to work - but maybe this is unduly pessimistic?
If the argument for it is to advance high energy physics more generally then a more diverse approach could reasonably be argued to bring more return.
It's been pointed out that even the most advanced tokamak designs (we're talking post-ITER, post-DEMO, meaning probably 100 years away) are so far below the plant power density of current fission reactors that they can't possibly compete with them.chrismb wrote:I've no idea where this view that tokamaks are a 'dead-end' or are otherwise 'non-viable'.
ITER is a great science project and has the best chance of actually producing net power, but Polywell has a much better chance of being an economically viable power source, as do FRCs.
Remember, Polywells were developed by Bussard in response to the instability problems in tokamaks. That's why they have convex fields everywhere: better MHD stability.After 25 years, Polywell doesn't yet even KNOW what its instabilites will be. Why is there a presumption that there won't be any, or if there are any they'll take less than 25 years to fix??
Do you mean "Remeber the theory"...that's how tokamak research got started, as a 'fix' for the instability problems of toroidal pinches!!!TallDave wrote: Remember, Polywells were developed by Bussard in response to the instability problems in tokamaks. That's why they have convex fields everywhere: better MHD stability.
chris,
Neutrons per dollar is not the proper measure for a power producer. It is kwh per dollar. Neutrons per dollar is for science fair projects.
If you are strictly interested in neutrons per dollar a fusor built of scrap materials is the way to go.
What you have to look at for a power producer is - if it works and none of them are that far along - what is the range of watts per dollar and kwh per dollar. Assuming fuel costs will be negligible vs amortization of capital.
Since the ITER is a steam plant device real break even is a Q of 3 (roughly). For pB11 direct conversion (the impossible dream) a Q of 1.5 will do.
Now it is rather obvious that the Tokamak boys would be much better off with small research reactors specifically designed for materials study. All the stuff cut out of the latest (coming) ITER plan.
The beauty of Polywell is that for $200 million you can get a yes or no answer for a cost which is about 1/100th of ITER and 1/10th the time or better going forward. Same thing for some of the other promising experiments. And the final costs for a working reactor scale as one over beta squared roughly. As you would expect.
Give me $200 million and I can produce neutrons as copiously as ITER with a fusor design. Even if it NEVER becomes a net power producer.
Neutrons per dollar is not the proper measure for a power producer. It is kwh per dollar. Neutrons per dollar is for science fair projects.
If you are strictly interested in neutrons per dollar a fusor built of scrap materials is the way to go.
What you have to look at for a power producer is - if it works and none of them are that far along - what is the range of watts per dollar and kwh per dollar. Assuming fuel costs will be negligible vs amortization of capital.
Since the ITER is a steam plant device real break even is a Q of 3 (roughly). For pB11 direct conversion (the impossible dream) a Q of 1.5 will do.
Now it is rather obvious that the Tokamak boys would be much better off with small research reactors specifically designed for materials study. All the stuff cut out of the latest (coming) ITER plan.
The beauty of Polywell is that for $200 million you can get a yes or no answer for a cost which is about 1/100th of ITER and 1/10th the time or better going forward. Same thing for some of the other promising experiments. And the final costs for a working reactor scale as one over beta squared roughly. As you would expect.
Give me $200 million and I can produce neutrons as copiously as ITER with a fusor design. Even if it NEVER becomes a net power producer.
Engineering is the art of making what you want from what you can get at a profit.
You seem to be replying for the sake of it. Each neutron is equivalent to a given amount of kWh, it really is much the same thing.MSimon wrote:chris,
Neutrons per dollar is not the proper measure for a power producer. It is kwh per dollar. Neutrons per dollar is for science fair projects.
Oh, yeah, forgot. A x2 difference is really going to make a BIG difference to viability when there's just 12 orders of magnitude to get over first!!MSimon wrote: Since the ITER is a steam plant device real break even is a Q of 3 (roughly). For pB11 direct conversion (the impossible dream) a Q of 1.5 will do.
Once Polywell gets anywhere near the 12 orders of magnitude better it needs to to come close to tokamaks, then it'll have me hammering down the politico's doors, make no mistake.....SHOW ME THE NEUTRONS!!!...
Let me see if I can help you out. Give me a 10X bigger volume (3 m vs .3 m) and I have just gotten within 9 OOM.Oh, yeah, forgot. A x2 difference is really going to make a BIG difference to viability when there's just 12 orders of magnitude to get over first!!
Give me 100X the magnetic field and I am now within 1 OOM. Close enough. And I will do it for 1/100th the cost of ITER. And I can actually do better than that because the magnet field possible scales inversely with size (up to the limit of the SCs) so it is more than possible I can do better than ITER at a lower cost per neutron.
And that is just by scaling laws that are well known.
And what would a .3 m across tok produce with .1 T fields? Apples to apples.
Engineering is the art of making what you want from what you can get at a profit.
What does "more than possible" mean?MSimon wrote:so it is more than possible I can do better than ITER at a lower cost per neutron.
Sorry, forgot to mention ITER before: So while JET works out at 1E12 neutrons per US dollar, ITER has a planned 3dpa design programme, giving a calculation of about max neutron emissions of 3E27 neutrons. If it runs to that estimated maximum and does so in its 5 billion euro budget that would work out at:MSimon wrote:And I will do it for 1/100th the cost of ITER.
ITER (current budget versus max neutron emissions) = *** 6E17 neutrons per US dollar ***
Which is nearer to 18 orders of magnitude over Polywell, currently. let's knock an OOM off that so that we have a 50billion budget to get the thing built with, then it's *only* positioned 17 OOM above Polywell. Sorry, but as things stand at the moment Polywell is an interesting curiosity, but not a contender. That could change in an instant, but as I've said before, various tokamak projects were kicking out multi-trillion neuts/s for a few $100k so Polywell has no 'excuse' for not beating that if it is truly destined for bigger things.
Not sure what all the point of this "which one's got a bigger ...", but does serve to support my view on polarisation. Both projects appear to me to be generally justly funded, and currently by an amount *not hugely* disproportionate to the needs of their current realistic scientific objectives. Only those evangelised in the respective faiths appear to think otherwise. I would give both projects what they ask, funding science projects always gets my vote - but I don't think either need much more than they're currently getting. JET is already equipped to run tritium and is not yet anywhere near its original neutron budget (which could also be extended as it is no where near 3dpa) so there is plenty of more work that could be done there at relatively little cost, yet the plan is to close it down soon. Why? If I had a vote on an *extra* $200M, sorry, but I would certainly argue to feed that into JET at this current time, not Polywell, because JET has delivered consistently within the scope of physics that it can physically cover and there is yet more plasma physics that I think could be usefully discovered at JET.
chris,
You never did answer my question so I will repeat it.
What could the tok guys do (pulsed wise) with a $2 million budget, a 5 man team, a device with .1 T fields and whose core dimensions are .3 m across?
Apples to apples my man.
You never did answer my question so I will repeat it.
What could the tok guys do (pulsed wise) with a $2 million budget, a 5 man team, a device with .1 T fields and whose core dimensions are .3 m across?
Apples to apples my man.
Engineering is the art of making what you want from what you can get at a profit.
I'm not sure how much sense this measure makes. The relationship between dollars and neutrons is obviously not linear. The first dollar doesn't buy you any neutrons, a billion dollars buys you considerably more than 1000x what a million dollars buys you, etc. This measure is always going to favor the designs that already get the most money, because of how power scales.ITER (current budget versus max neutron emissions) = *** 6E17 neutrons per US dollar ***
A better measure would be: given a certain level of neutrons, how much does a given design to produce it cost? ITER and the WB-100 are within an order of magnitude of each other in terms of neutron production, and WB-100 should cost about 100x less.
Because, like ITER, it's a great science project but has relatively little potential practical value.JET is already equipped to run tritium and is not yet anywhere near its original neutron budget (which could also be extended as it is no where near 3dpa) so there is plenty of more work that could be done there at relatively little cost, yet the plan is to close it down soon. Why?
In terms of commercial applicability, Polywell is a contender while ITER is the (very expensive) curiosity.Sorry, but as things stand at the moment Polywell is an interesting curiosity, but not a contender.