Problems with Nuclear Fusion

I said study not "use", but, since you asked for just one... muon catalyzed fusion is used to build large nuclei for study.
Really? The birth of one muon IIRC 210 MeV even neglecting low efficiency of process followed from low selectivity.
How many fusion events can you provide in lifetime of one muon - IIRC about 1 microsecond?
 
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I doubt on "a lot".
Can you mention one more reason of usage fusion except power generation or weapon?
Space traveling? Actual? We live in the end of oil era, when risk of big nuclear conflicts are neglectable with increasing risks of asymmetric conflicts in which technology advanced countries fight with outdated combatants and therefore only power generation is significant for us today. Because of it DOE and similar other organizations are the best payers. And not for example NASA and DOD.
Space travel is both. Either you use the reactor for power, or you blow up a bomb behind you and surf the blast.

Defence company Lockheed Martin last week at Google's Solve for X announced they will have fusion power prototype in 4 years(!). He predicted they can generate 100 MW by 2017. I do not think his claim is realistic.

Google's solve for X: https://www.solveforx.com/

You can find the Lockheed fusion presentation in the moonshots section but a copy is here: He shows the Lockheed Martin prototype fusion reactor.

DoD is funding a lot more fusion reserch tha you probably think. They want to stop buying oil from people they do not like, and they need electrical power for lasers. NIF is a defense lab not because their laser is weak but because "scientific curation" of nuclear weapons was theiroriginal mission .
 
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Space travel is both. Either you use the reactor for power, or you blow up a bomb behind you and surf the blast.

Defence company Lockheed Martin last week at Google's Solve for X announced they will have fusion power prototype in 4 years(!). He predicted they can generate 100 MW by 2017. I do not think his claim is realistic.

Google's solve for X: https://www.solveforx.com/

You can find the Lockheed fusion presentation in the moonshots section but a copy is here: He shows the Lockheed Martin prototype fusion reactor.

DoD is funding a lot more fusion reserch tha you probably think. They want to stop buying oil from people they do not like, and they need electrical power for lasers. NIF is a defense lab not because their laser is weak but because "scientific curation" of nuclear weapons was theiroriginal mission .
I've seen Lockheed's presentation. There are many words about challenges humanity has. But nothing about what kind fusion (concept) they are going to do in such short time period. If that is a presentation - very strange presentation.

If you have better idea how much money DoD funded in fusion research, please provide numbers. Because I am sure that that number will be on orders of magnitude less than DoE done.

And I am afraid that making decision from whom crude oil should be purchased is not a DoD's competence. :)

You want to avoid dependence of your country on oil producers?
How about to change interstate transportation structure? To develop for example railway cargo moving (infrastructure of which is weak in USA as far as I know) instead of transportation by trucks? You would get about twice reduction in oil consumption from 10 to 5 millions barrels per each day. And required more electricity to produce on fission nuclear plants.
But that is not of interest of such American companies like Exxon, Chevron, Halliburton, etc. Also this solution is not of interest of many people involve in automotive industry.
Do you think that there is any problem with fission power generation? Or fusion will be cheaper? No.
Will fusion power plant be smaller than fission one? Again – no.
At least from the beginning fusion will not be cheaper and smaller and therefore timescale 30-50 years for its development is acceptable for country seriously thinking about future.
 
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US FUSION BUDGET 2013

US government R&D spending for 2013. It's free despite having a buy button.
http://www.aaas.org/spp/rd/rdreport2013/ [Broken]

They have summary tables
http://www.aaas.org/spp/rd/rdreport2013/tablelist.shtml

Let's look at DoE (Dept of Energy)

table II-11, DoE R&D 2013 by function (pg 148)
* defence = 4691m
* general science = 4568m
* energy = 2644m
* Total 11,903m
Now we see DoE spends more on defence than on energy.

The page 151 shows why:

DoE Atomic Energy Defence Activites (pg 151) (total not just R&D)
* atomic wpns science 7577m
* --- science 350m (fusion? dont know)
* --- engineering 151m
* --- Internal Confinement Fusion 460m
* --- simulation and computing 600m (fusion simulations)
* nuclear nonproliferation 2,500m
* naval reactors 1,050m
* office of adminstrator 141
* Total ~12,000 of ~27,000 total

So we see that DoE pays for all the atomic bombs and military reactors. They also pay for the US fusion program under their Defence allocation. It (defence) is about half of DoE's total budget.

Examining the fusion funding:

US Fusion program Breakdown (pg 150)
* science 154
* facilties 221 (*)
* iter 150
* enabling R&D 23
* total = 398 (of 460 --- 62m unaccounted for)

(*) Includes NIF. I also dont know why you say their laser is weak; it is the world's largest. They are a bomb lab first and a power lab second.

Offtopic: HeP 777. Nuc Physics 527. I read around HeP and it says they are pretty much cutting back, but maintaining their CERN participation.

Let's look at DoD funding. DoD does not give a meaningful breakdown of what spends on, but its total R&D budget is 72,500m (plus they have another block of money reserved for them that they have to ask to use) compared to 11,903 for DoE. DoD has 2 publically announced fusion projects, being EMC2 and Whiffleball, both attempts to build a shipboard fusion reactor.

DoE spending on fusion is probably greater than DoD spending. I never said it wasn't. However I did say that, one, much defence money goes into fusion but not for power, and this disorts public perception because they think fusion cash is power cash; two, in addition to the above mentioned US fusion budget, DoD does have its own seperate fusion program.

Some "US" fusion research is being done privately too but it hard to call it "American" when it's done by a corporation who is employing people from all over world and likely to sell it overseas too. However the US govt's major contribution to civillian fusion research seems to be their donation to ITER.
 
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I also dont know why you say their laser is weak; it is the world's largest.
Yes, NIF lasers are very powerful but I said “efficiency of laser is weak – about 1% or little more or little less”.
This efficiency does not allow getting a positive energy from NIF in either way at any realistic Q factor of hohlraum.
DoD has 2 publically announced fusion projects, being EMC2 and Whiffleball, both attempts to build a shipboard fusion reactor.
Both or the same? And 3 or 4 people worked, only several millions were spent and only for the first phase. One NAVY's missile worth more. As result several table-top machines with no scaling at all. The last machine shoed fractions of milliwatt fusion power with kWs input.
 
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NIF is an experimental facility that is supposed to support inertial fusion research for power applications, support the Stockpile stewardship program (Weapons), and support basic science research in high energy density physics.

I don't remember the exact numbers but NIF periodically publishes the breakdown of their shots by purpose. The power campaign by far received the most shots. (~300+), the weapons program was next (~10-100), and finally the basic science programs only received a hand full (~10). I've emailed a friend to see if he knows the exact breakdown.

I don't deny that NIF has weapon applications, but to date most of the research on NIF has gone to support peaceful purposes not weapons.

I also want to clarify that NIF and most of the ICF research is supported by the NNSA (National Nuclear Security Administration). The office of Fusion energy sciences funds magnetic confinement research and basic plasma physics. The facilities budget under the OFES does NOT include NIF. It does include DIIID, NSTX, Alcator C-MOD, MST, and smaller scale experiments.

As for other uses of fusion, power is by far the big one, but people are interested in fusion as a neutron source. These sources can be used to detected clandestine materials (explosives and nuclear material). They can also be used to create medical isotopes like Tc-99m.

I stated above the DOE OFES supports basic plasma sciences. Plasmas are huge in the the semi-conductor industry, and currently responsible for the continuation of Moors law. Magnetic confinement experiments like MRX study magnetic reconnection which helps us understand space weather. This is important for the telecommunications industry, because they have to shut down or move the satellites when solar storms send highly energetic particles our way. There are also many similarities between plasma turbulence and atmospheric turbulence.

Finally fusion research drives research in high temperature super conducting magnetics, cryogenics, vacuum technologies, durable materials the can survive extremely harsh environments, high fidelity computation, etc. The applications of which extend far beyond power.
 
I don't deny that NIF has weapon applications, but to date most of the research on NIF has gone to support peaceful purposes not weapons.
Agreed. People put in the word "weapon" some mystic sense. While weapon is also an engineered product like many others and while NIF is a typical inertial confinement approach similar to canceled now "Light Ions Fusion" and not yet heavily started "Heavy Ions Fusion". May be in the program scale some weapons simulations was done. I really can not imagine what but funding from DoD is the fact. As well as fact is that at today's level of technology laser fusion has not any posibility to produce net power.
 
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Further checking reveals you are correct that the source of NIF funding is NNSA not OFES, but both are DoE from the military portion of the budget.

I was recently reading an article on NIF

http://www.nature.com/news/laser-fusion-put-on-slow-burn-1.12016
The US$3.5-billion NIF uses lasers to crush a 2-millimetre pellet of hydrogen fuel to the point of fusion. Rather than irradiating the fuel directly, the lasers shine into a cylindrical capsule. The capsule walls then emit X-rays that squeeze the fuel pellet until it explodes (see diagram).

This indirect approach mimics the ignition system in a thermonuclear weapon, which uses radiation from a fission 'primary' stage to squeeze hydrogen isotopes in the fusion 'secondary' — creating a powerful explosion.

The NIF's main mission is to gather laboratory data on the process to help weapons scientists to care for the ageing US nuclear stockpile
Now it seems they are having trouble achieving ignition via this method and are having to explain it to congress, and now are refocussing their efforts to fusion power.

http://www.physicstoday.org/daily_edition/politics_and_policy/nif_to_shift_emphasis_after_the_facility_s_failure_to_achieve_ignition[/URL]
[quote]"Ignition was never the endgame," Cook says. "The endgame is really stockpile stewardship." For NIF's applications to laboratory astrophysics and fundamental science, he adds, "the endgame is just having a very capable facility with diagnostics that can explore things that you can't otherwise go out and measure."[/quote]

In other words, they have no concrete goal or objective for civillian power generation - their one concrete goal was weapon curation. If NIF is currently rebranding itself towards fusion power, that's only because of problems in their primary mission (weapons).

It really did surprise me how slowly fusion power was progressing despite all the money being spent on it, but then I realised that a lot of the money being spent on fusion isn't going towards power.
 
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jim hardy

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I didn't want to write too much in case nobody was interested. .......
....I was more interested in pointing to an example of low-temp fusion that wasn't junk science.

Fusion does not have to involve very high temperatures but:
1. the high temperature projects look like they have more promise these days
2. there is a lot of junk and pseudo-science around low-temp fusion ideas to trap the unwary investor.
In your opinion is there any hope of break-even via electrostatic confinement?

http://ssl.mit.edu/publications/theses/PhD-2007-DietrichCarl.pdf

My math is not good enough to judge.

old jim
 
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It really did surprise me how slowly fusion power was progressing despite all the money being spent on it, but then I realised that a lot of the money being spent on fusion isn't going towards power.
E.g., Heroin (diacetylmorphine*hydrochloride) was developed as medicine drug but now is marketed only by clandestine dealers. As its properties does not allow usage for medical application. History of science knows many such examples when failure in one branch gives some results used in another.
 
In your opinion is there any hope of break-even via electrostatic confinement?

My math is not good enough to judge.

old jim
No any hope. As electron beam injected into background plasma - typical conditions for two-stream instability.
There are three ways for mitigation such type of instability:
1. Beam is relativistic
2. Axial mag field is applied
3. There should be wide enough velocity spread causing Landau damping
Ref: Stanley Humphrey Jr., "Charged Particle Beams"
Neither ways are possible for electrostatic confinement in that form how that is promoted by developers.
 

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Really? The birth of one muon IIRC 210 MeV even neglecting low efficiency of process followed from low selectivity.
How many fusion events can you provide in lifetime of one muon - IIRC about 1 microsecond?
About 3-400 in d-t mixtures (c.1985 with He3 - there are more recent papers claiming higher yeilds) but it only matters if the idea is to generate power. That is not the core reason for this research so the number of fusions per muon only goes to the energy cost and time-frame of the experiment. People researching very heavy atoms are prepared to run their experiments for months to get enough atoms to study.

So the low fusions/muon count is irrelevant to the claim being made.

Fusion is a handy tool for building big atoms from small ones. If your interest is to study these big atoms, then you will want to understand various kinds of fusion so you can make the kinds of atoms you need when you want them. There's a group (LLNL et al) in Livermore Calif. using inertial confinement fusion (Ca+Am) to make No.118 for eg.

This is a reason for studying fusion which is not (directly) related to power plants of bombs... as per my claim earlier.

There are many current research projects involving fusion that are not aimed at power plants or bombs... a quick trawl of google scholar show a great many papers generated in the last few years in μcf alone. Pure science research does happen.

Mind you - power generation does dominate the research and discussions (like here).
 

Simon Bridge

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In your opinion is there any hope of break-even via electrostatic confinement?
Asking me??
It's been a while and IEC appears to be a development since I've last done a lit review (μcf was a possible PhD thesis.) The rules don't seem to have changed though.

The example looks like a variation on Bussard Polywell fusion. I've never been able to get enough information in one place to assess those properly. The general approach is attracting real researchers, which is a good sign there's valid physics in there, but I'm inclined to go with Joseph Chikva on this one: it would require something close to a paradigm shifting breakthrough to use the approach as a power source.

The paper in the link just presents a computer model rather than physics, and it is part of a PhD rather than appearing in a peer-reviewed journal. I'd want to know what has been done to test the computer model. Look at the dates: 1999, 2003, 2007? If it was really so promising a decade ago, then the model would have been tested ... so see if you can find the test. (good exercise for you).

I think the original question in post #1 has been answered though.
 

mheslep

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Brothers Right too demonstrated flight only on some hundred meters, ...
I like the analogy if it is drawn tightly enough.

The Wrights demonstrated not just a way to leave the ground but via heavier than air, powered and controlled flight, their 'break even' for aviation if you will. Plenty of people had left the ground previously, in balloons or simple jumps off a a tower with a lot of drag. The latter is really the better analogy for current fusion technology: jumping off a cliff with a crude parachute which really does not get you anywhere, certainly not to a net power economic reactor.

Plenty of hand waiving exists about fusion being just around the corner, just as there was for centuries before the Wright Brothers 1903 flight. I think instead of this being fusion's 1903 it could just as easily be 1803, with a century yet to come of people jumping off cliffs before something useful happens.
 

mheslep

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In your opinion is there any hope of break-even via electrostatic confinement?

http://ssl.mit.edu/publications/theses/PhD-2007-DietrichCarl.pdf

My math is not good enough to judge.

old jim
I think T Rider put a stake in the heart of the possibility of net power production from electrostatic fusion with his 1995 publication. This paper by Dietrich actually references Rider as setting fundamental limits (less than unity), but hopes to approach them. Without reading further I suppose there could be some benefit to operating at a loss for space propulsion.
 
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About 3-400 in d-t mixtures (c.1985 with He3 - there are more recent papers claiming higher yeilds) but it only matters if the idea is to generate power. That is not the core reason for this research so the number of fusions per muon only goes to the energy cost and time-frame of the experiment. People researching very heavy atoms are prepared to run their experiments for months to get enough atoms to study.
In Soviet Union in 60s or 70 the so called "Muon Fabric" was built. The idea was in collisiosin of two very high energy particle beams for creation of muon.
My father being a physicist then asked one man involved in that project when met him at one conference: "how your Muon Fabric?" on which he got an answer "one meason per one season". For ref: "meason in Russian is "muon".
Process is extremelly nonselective and if rest mass of muon is 209 MeV, you should devide that number on selectivness of process and also on energy effeciency of accelrators.
As result you would get many GJ have to be spent on birth of each muon. Then compare that number with 400 (fusion event)/muon *17.6 MeV/(fusion event) = "only" 7 GeV/muon

What do you think how much enerhy should be spent on one muon birth using today's technologies? More or less than 7 GeV
Also 400 events per muon is too optimistic estimation. As I've seen 10-20.
Good luck.
 
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I like the analogy if it is drawn tightly enough.

The Wrights demonstrated not just a way to leave the ground but via heavier than air, powered and controlled flight, their 'break even' for aviation if you will.
The analogy in that the Wrights execute their first flight on heavier than air device a little better than today's fusion experiments execute fusion. But TOKAMAKs are really close to ignition.
 

Simon Bridge

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... and how long before the Wright's "break even" demonstration and the first commercial aircraft?
 

Simon Bridge

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In Soviet Union in 60s or 70 the so called "Muon Fabric" was built. The idea was in collisiosin of two very high energy particle beams for creation of muon.
My father being a physicist then asked one man involved in that project when met him at one conference: "how your Muon Fabric?" on which he got an answer "one meason per one season". For ref: "meason in Russian is "muon".
I had to read a lot of Russian papers from that period - yes. I get headaches just recalling them.
FWIW: muons were once called "mu mesons" everywhere because it was thought that they were a kind of meson - the particle predicted, in 1935, to carry the strong nuclear force. The excitement was premature - muons are a kind of lepton. The name was still in use in the 60's - as in this famous film from 1963.
Time Dilation - An Experiment With Mu-Mesons

What do you think how much enerhy should be spent on one muon birth using today's technologies? More or less than 7 GeV
The ISIS muon group in the UK has the strongest muon source. They make them from pions.
http://www.isis.stfc.ac.uk/groups/Muons/
Also 400 events per muon is too optimistic estimation. As I've seen 10-20.
Good luck.
You havn't been looking very hard (perhaps you stopped looking before 1984?)
http://adsabs.harvard.edu/abs/1986Natur.321..127J
"as high as 150 per muon" (1986)
http://www.sciencedirect.com/science/article/pii/0920379689900239
"100 per muon" (1989)
http://prl.aps.org/abstract/PRL/v86/i17/p3763_1
"200 per muon" (2001)
... that's without really trying.

But I say again: it is irrelevant if there are 100s or 1 a week; it does not matter - because this is not for power generation or weapons research. Which is the whole point of the example.

The gauntlet was thrown to provide one example of fusion research that is not for power plants or weapons and that I have provided. There are others.
 
Fusion is a handy tool for building big atoms from small ones. If your interest is to study these big atoms, then you will want to understand various kinds of fusion so you can make the kinds of atoms you need when you want them. There's a group (LLNL et al) in Livermore Calif. using inertial confinement fusion (Ca+Am) to make No.118 for eg.

This is a reason for studying fusion which is not (directly) related to power plants of bombs... as per my claim earlier.

There are many current research projects involving fusion that are not aimed at power plants or bombs... a quick trawl of google scholar show a great many papers generated in the last few years in μcf alone. Pure science research does happen.

Mind you - power generation does dominate the research and discussions (like here).
Yes, in my mind power generation is dominant. And I never thought to call "fusion" to reaction of synthesis of No. 118 element. May be because of my bad English.
Thanks.
 
But I say again: it is irrelevant if there are 100s or 1 a week; it does not matter - because this is not for power generation or weapons research. Which is the whole point of the example.
Irrelevant? How about people who want to use muon catalyzed fusion for power generation? http://en.wikipedia.org/wiki/Muon-catalyzed_fusion#Deuterium-tritium_.28d-t_or_dt.29

http://www.rikenresearch.riken.jp/eng/frontline/5976 [Broken]
http://www.rikenresearch.riken.jp/images/figures/hi_4014.jpg [Broken]
 
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mheslep

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Basic problems with Muon catalysed fusion.
i) The relevant lifetime of the muon for fusion catalysis is based on the odds of muon capture by an alpha, which is 0.5%. So the theoretical upper limit is ~200 fusions per muon.

ii) The energy required to create a usable muon is not just its rest mass.
Brunelli & Leotta said:
  • Muon rest energy 106 MeV)
  • Made from pi- 139 MeV
  • Make stuff other than pi- x 10
  • Lab vs. CM frame x 2
  • Accelerator efficiency x 2
Present muon production ~5 GeV
So muon catalysed fusion is waiting for someone to figure out to avoid alpha capture and get the fusion events per muon up to ~400.
 

mheslep

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The analogy in that the Wrights execute their first flight on heavier than air device a little better than today's fusion experiments execute fusion. But TOKAMAKs are really close to ignition.
We can't know that is this case until after the fact
 

mheslep

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Simon Bridge

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Yes, in my mind power generation is dominant. And I never thought to call "fusion" to reaction of synthesis of No. 118 element. May be because of my bad English.
Thanks.
I don't think so - most people have a problem changing context... and this thread is about power plant problems after all. See below:
Irrelevant? How about people who want to use muon catalyzed fusion for power generation?
That is also irrelevant ... in context of the comment. I was responding to an earlier challenge. vis. The gauntlet was thrown to provide an example of fusion that was for something other than power or weapons - the fusions-per-muon is irrelevant in that context ... except as I have already stated. The whole challenge and response is only an aside to this thread which is about fusion power plants and the problems with. I am well aware of the people trying to get a μcf plant working - it was my field for a while.
So muon catalysed fusion is waiting for someone to figure out to avoid alpha capture and get the fusion events per muon up to ~400.
... for the approach to be feasible for power generation.
There's a whole bunch of people trying. I remember that the sticking problem (then called He3 poisoning iirc - He4 seems happy to give up the muon) was worse if the muon went right to the 1s state instead of going through 2s, so one of the things I tried to figure was a way to make the 2s state likely. Ho hum.

Are people only just noticing these comments? They've been going parallel to the Tokomak discussion. It started out in page #1 of this thread as an aside about how fusion needn't involve super-high temperatures. Perhaps a review of past comments is in order - to avoid over-reiteration? But maybe a bit of reiteration is needed?
 

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