Skunk Works Reveals Compact Fusion Reactor Details
aviationweek.com
aviationweek.com
Problem with fusion research like this is that the closer you get self sustainment or energy generation, the harder it gets and problems pile up. This project looks like many other similar projects that have gone bust. They start by solving the easiest problems first, get some funding and hit the wall.
The main problem with any reactor design is how to handle the 14 MeV neutrons produced by the fusion reaction (no mention in the article). They tend to damage the reactor and make it economically unfeasible. At this point being able to create fusion reaction is not the main challenge. It's the sustainment and economics of limiting the damage. If they really have solved all the problems and demonstrate economically sound fusion in 5-10 years, they will be handed Nobel price in physics for sure.
The challenges of fusion power are largely fundamental nitty gritty engineering issues. We know fairly well how to design most of a fusion reactor; in a lot of ways they are conceptually easier than fission reactors.
The two main hurdles are the materials problems and how to keep the reaction critical with radiative heat loss. These are big problems that so many times have been ignored by people claiming to have solved fusion power. You just can't get away from them, but solving them would be truly revolutionary.
I'm not saying they don't have something novel here as they really are some fine researchers at Skunkworks. Just temper your expectations.
I'm not saying they've done it and extraordinary claims require extraordinary proof but this is the place that made a Mach 3.5 jet with wings that leaked out of titanium in the 60's.
Nitty-gritty engineering is something they are fairly good at.
Time sell any oil company stocks, mutual fund holding?
Actually even if you believed there's a chance this Lockheed concept can work, the time to buy airline stocks would be on the back end of this dead bull market that's about to fall off a cliff. And then there's the 20 year wait before it's finally deployed to a commercial airplane.
True?
I wanted my Ph.D. in mathematical physics, but all the physics courses I could find did the math in very sloppy ways, and my hope for any research progress in physics wanted to do the math with full care. I did get much of that math, but by then I was occupied with my money making work and didn't get back to physics. I'd like to, maybe, someday! Then maybe I'll be able to give you a solid answer.
For now, some of the discussions claim that a lot of neutrons will make a metal brittle but don't go the next step and explain just why. Before I'd say anything about what neutrons do, if only as a check on the level of understanding, I'd want to know why.
http://en.wikipedia.org/wiki/Wigner_effect
Whatever production process partially relies on arranging the crystal structure of the metal to arrive at desirable properties, the neutrons disrupt it.
(if it doesn't follow why that would matter, look into the heat treatment of steel)
Neutrons are interesting in that they dump all their energy into a very small region. Instead of losing energy continually and gradually, they travel a ways and then dump all their energy into one spot. This makes them potentially very useful for things like cancer treatment (you can select neutrons to ensure they deliver most of their energy into the cancer, rather than evenly along their travel path). I suspect this effect means that, for reactors, the wear and tear is more localized, but of a larger amplitude.
Not exactly. The initial collisions do indeed cause localised damage cascades, but the overall effect of a large neutron flux is embrittlement of the material. This is a problem already in fission reactor vessels, but the neutron fluxes are a whole order of magnitude larger in fusion reactors, and it's a very difficult problem to solve. To my knowledge, current materials can only just about deal with with the neutron fluxes in standard fission reactors, with no current materials being capable of withstanding neutron fluxes in a fusion reactor over any long (i.e. commercial) timescale at present. It would be a big achievement and a big jump in materials science to discover such a material, completely separate of any fusion project.
(Disclaimer: this is not remotely my field, but I have looked at some of this stuff in the past, and been to talks about ITER.)
Frankly, the best neutron shielding in the world, on a per-cost basis, is water with borax. I don't know why people don't use this more. We used to use stacked bags of borax as neutron shielding when I built a fusion reactor (non-self sustaining, of course), and we had more than enough shielding to handle 2.45 MeV neutrons for under $1000.
A cool thing about the shield being liquid is that you could theoretically replace it while it's running. It could make the neuron shield double as the heat transfer medium too.
Of course I'm a total layman so this is just highlevel blabbering.
Neutrons slow down via interaction with nuclei (all of which except hydrogen are heavier) so they lose energy slowly and scatter all over the place. They have no definite range (search for "fermi age theory" to get a rough idea of the distribution) and can't be meaningfully beamed (unless they are ultra-cold, which is not relevant to fusion power.)
I've made a longer comment above that goes into neutron physics in a little more detail.
Fusion neutron (14 MeV) from fusion reactor is exactly as energetic as fusion neutron emitted by a neutron bomb and causes equal damage (just distributed over longer time). They have 10x as much energy as fission neutrons and travel at speed of 52,000 km/s (17.3% of the speed of light). Neutron capture before they hit and damage magnets, electronics or wear out materials is important part of the fusion reactor design.
Neutrons are radiation. Also It's the worst kind of radiation because unlike X-rays or Gamma, neutrons make other things radioactive.
Source for this claim: http://en.wikipedia.org/wiki/Neutron_activation
Neutrons are radiation, but not electromagnetic radiation. I'm guessing that nitpicking this is why you were downvoted? Dunno.
Two points made reply to you are correct: neutrons are radiation, but not electromagnetic radiation; and neutrons can make other things radioactive.
Some thing other people are saying are less correct: any individual neutron will deposit most of its energy in one place, but averaging over many neutrons their energy deposition will be spread out. Furthermore, neutrons will come out in all directions. The problem of neutron damage is not small, but no one seriously believes it's a show-stopper.
Neutrons are the exploding billiard-balls of nuclear physics. Fusion produces "fast" neutrons, with moderate energies. This is a deuterium-deuterium device, so most of the neutrons will come out with 2.4 MeV, which happens to be the same as fission neutrons. The DD reaction produces tritium as a byproduct about half the time, though, and DT fusion will lead to 14 MeV neutrons. There will be fewer of these in most designs, and some designs incorporate ideas to get rid of the tritium quickly to suppress these higher energy neutrons.
At high energies neutrons don't tend to interact very much with light nuclei, and for a variety of reasons fusion reactor design is dominated by light nuclei. What they do do is bounce off, which is where the billiard-ball analogy comes in. Each time a neutron bounces off another nucleus it loses energy (because the nucleus it bounces off of recoils, carrying some energy with it.) This is just pure Newtonian mechanics.
Neutrons typically travel a few metres in the process of slowing down, depending on the material. Light materials slow them down faster: a light ball bouncing off a heavy ball doesn't loss much energy, but bouncing off another light ball it does (hydrogen is the best material for slowing neutrons down because of this, and hydrogen-rich materials like water are good too.)
The neutron never completely stops because the nuclei it is bouncing off of are in thermal motion. At room temperature a neutron in thermal equilibrium moves at about 2200 m/s. But not for very long, because this is where the exploding comes in.
You can think of it in these terms: once thermalized, a neutron is passing by other nuclei rather slowly (2200 m/s is slow when you're a neutron). This gives it lots of time to react with nuclei, rather than just bouncing off, and eventually it does. When a nucleus absorbs a neutron it becomes a different isotope of the same element, and in many cases adding a neutron to a stable isotope makes it radioactive. Carbon-12 is a stable isotope that, with the addition of a neutron becomes carbon-13, and if it happens to get another neutron added later on, radioactive carbon-14.
Neutrons are a pain, even to fission engineers, and fission depends absolutely on them to happen. They get everywhere, are hard to shield, make stuff radioactive and damage materials. But we know pretty much how to deal with them, and it's unlikely they will make the difference between working and not working in a device like this.
Putting a mice next to this system can make it a "carbon-14" mice? Can it glow in the dark? :-)
Honestly, those folks that stand back with their arms crossed watching you fail, and reminding you the whole way that you might fail, are the biggest pains in my ass in this profession. By a mile.
Maybe you can contribute your wisdom by going to Lockheed, instead of Internet commentary in which you bet against them?
It's turtles all the way down. Guess we should just give up on Internet commenting. /s
That's a good way to lose your comment-voting privileges - I just noticed my ability to vote on comments disappeared at some point.
What I said, reworded, was the people who sit on the sidelines of anything and tell you, while you are trying something, that it won't work are among the worst people in the profession. I didn't say believe harder. I don't give a damn what you believe and don't need you reminding me, constantly, that my project has a chance of failure. Keep it to yourself or get on board. That's my point.
I am not a kind person, so that you'd ascribe feel-good nonsense to me is downright hilarious. I can handle it but a lot of people can't, and it's really, really tiring to keep a team from becoming demoralized when there's a naysayer popcorn gallery in every thread and watercooler discussion.
You know what demoralizes a team like nothing else? And endless litany of projects that failed because nobody wanted to listen to the people pointing out problems.
When people on the team think they are pointing out problems, but are doing so without support, by simply saying "That won't work" instead of "That won't work because of ...".
This does nothing to further a project and leaves the burden of proof for a working solution on the person who proposed the solution in the first place, and the way for them to prove their solution is to continue working on it, with no actionable feedback to revise their project on.
In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (physics will beat you over the head at every step). You can cross your arms and say "that won't work" and you'll be correct 97% of the time. Fusion is something that some of the smartest people in the world, with enormous amounts of money behind them, have been beating their heads against for the last half century or more. Somebody will figure it out, eventually, but statistically, any given project is very likely not to be the one that does, and it will almost certainly take much longer than the optimists assume it will take.
Did you know that coal plants, which still make up the majority of U.S. energy production, are only about twice as efficient today than they were a century ago?
[1] Although math can be a kick in the ass too if you're working in domains where you can prove there are no polynomial-time algorithms for whatever problem you're working on. E.g. there is a reason people have been banging their heads on the garbage collection problem since the 1950's and it's still an active area of research.
There are certainly two ways of looking at that. The way I read your sentence it sounds very pessimistic. On the other hand, I look at that and say that over 100 year's we've managed to extract twice as much usable energy out of a pound of coal, through a variety of incremental improvements to what is fundamentally the same technology; and the world is a better place for it.
Wasn't most of the effort put into making them MUCH MUCH cleaner? I mean, the https://en.wikipedia.org/wiki/Cuyahoga_River doesn't catch on fire anymore, and the amount of https://en.wikipedia.org/wiki/Acid_rain seems pretty tolerable compared to the early 80's
I think both of these things happened, but only one of them is in the interest of a market actor.
it is only until that market actor is allowed to externalize the costs of his pollution
They too are a product of applying new discoveries and then engineering around the constraints of physics.
Things change. Progress is made.
Did you know that wind and solar are already at grid parity in over half the world? And that in many large first-world countries (Germany, Australia) the price of energy goes negative during daylight hours because of the amount of energy produced by renewables?
http://cleantechnica.com/2014/07/05/queensland-solar-negativ...
Similarly, if you're in California and you ever wondered why your electricity bill is 2x that of any other state, it is because you are the ones footing the bill for those subsidies. Without subsidies, wind and solar are far more inefficient at a $/MWH basis.
http://www.businessweek.com/articles/2012-10-21/when-it-come...
"Meanwhile, a recent report from the U.N. Industrial Development Organization notes that photovoltaic module prices have been falling at a rate of 15 percent to 24 percent a year for some time. In 2011, factory gate prices for crystalline-silicon photovoltaic modules fell below the $1-per-watt mark, often regarded as the point of “grid parity” for solar power. Earlier this year, they reached 85¢.
The “levelized cost of electricity” for solar, a measure of the average price of power over the lifetime of a power project, has fallen from 32¢ per kilowatt hour in 2009 to 17¢ in early 2012. These declining costs are a major factor behind an explosion in use. A report by the Natural Resources Defense Council calculates that from 2006 to 2011, wind, solar, geothermal, tidal, and wave electricity production increased from 1 percent to 2.7 percent of total US production, from 0.1 percent to 1.5 percent in China, and from 5.3 percent to 10.7 percent in Germany. One sunny Saturday in May 2012 saw Germany produce nearly half of its electricity from solar. Given the long life of power plants—often measured in decades—this rate of change is phenomenal. Again, five years ago, total global photovoltaic capacity was just 16 gigawatts. In 2011, the world added nearly twice that—29 gigawatts—of new capacity."
Note this article is from October 2012, two years ago. Renewable installations have skyrocketed, with subsidies far below what oil, gas, and other fossil fuels are provided with.
It is laughable for anyone to suggest that oil, coal or gas energy is subsidised when these numbers are calculated on wooly figures like access to land, or tax deductibility of research - the same rules that apply to all companies, software companies included.
The simple fact is that oil, gas and coal energy generates a magnitude more tax revenue than it ever gets in irritating or indirect subsidies, while the 'renewables' sector only ever takes subsidies and doesn't return net tax. This is plainly obvious based on the per mw/h cost of these technologies - there is no magic formula involved in selling something below average cost of production an making a profit, no matter how much volume you do.
You can't have your cake and eat it too. If you want to bring government subsidies for renewable into the discussion, you also have to consider the externalized cost of legalized pollution. The only defensible calculation is to look at cost per kilowatt hour excluding government subsidies and including externalized costs. That's the true economic cost of the energy source.
And coal is miserable on that front. I wouldn't be surprised if coal use is a net loss to the economy (i.e. the value of the energy generated by coal is less than the environmental cost of coal use).
That doesn't make any sense. Net loss to the economy? If you were to say a net loss overall, including environmental costs, I might agree.
The problem is that we don't measure economic activity accurately, because we ignore draw-down of capital (human, natural, or otherwise). Fukushima actually increased Japan's GDP for a quarter, because the damage-response activity gets counted in GDP while the loss of physical capital does not. Fossil fuel use suffers from this problem in two ways: 1) the value of the capital removed from the ground isn't counted (i.e. nobody counts selling off their family furniture as net positive income, but resource-rich countries count selling off oil or minerals as such); 2) the loss of human and environmental capital is ignored (strip mining mountains causes rain to wash away river banks, and that's money directly out of someone's pocket).
Coal is an energy dense naturally occurring product. The environmental damage from coal relates to mining, shipping and burning it. The environmental benefits of coal are that extraction, transport and burning doesn't happen to other things - ie, biomass, otherwise known as timber.
England has more forest now than it has for centuries, because a more energy dense substitute for energy was extracted (coal). In many developing countries, access to coal would be a net benefit, because it would reduce clearing and burning of vegetation, and because the ensuing affordable energy allows for more intensive food production, and the keeping of food inventories, further lessening the pressure on the environment.
Of course, everything that applies to coal also applies to natural gas even more so, and obviously to fusion even more than that. But this meme of 'coal is evil and must be stopped' ignores the reality of the situation and completely ignores the benefits of efficient energy production, especially in the case where real, persistent and preventable environmental damage is taking place because there is a lack of efficient energy productin.
Even pg discussed the phenomenon, as you undoubtedly know. There's a good idea, or a news article hailing progress, or some other kind of optimism, then the first comment is a mid-brow dismissal. They are the lowest-effort comments to make; "that won't work because X isn't well-respected and Y often happens to similar teams" requires almost no research and cannot really be refuted.
The only way to refute it is by calling a spade a spade, and look what I get for doing so: having my comment twisted to be fuzzy feel-good smarm crap, when really I'm just saying "shut up and get out of the way if you don't think it'll work."
As for "shut up and get out of the way"--whose way exactly? Unless you're a nuclear physicist, comments expressing hopeful optimism aren't very useful.
Right now, this entire story is just a waste of space on a hard drive somewhere in Palo Alto, and no comments pro or con are going to change that.
Also someone on reddit made an interesting observation about job openings at Lockheed: http://www.reddit.com/r/Futurology/comments/2jbgcf/lockheed_...
Software professionals recognize the constraints on development imposed by entropy, information theory, and other esoteric branches of mathematics.
Rather than scoff at this article because Lockheed is making extraordinary claims without the backing of extraordinary evidence, I prefer to scoff because nuclear physics modeling and simulation software is still software. If I cross my arms and say "that has a critical undiscovered bug in it that invalidates the results," I'd be correct 97% of the time. It also has a SQL injection vulnerability, links to at least one library written 30 years ago, and was originally written by a physicist that knew a little programming rather than a programmer that knew a little physics.
Conservation laws are the book-keeping of physics, and they act as global checks on correctness. If your code conserves energy, mass, particle number, charge, momentum, etc it is probably correct in the ways that matter, because it's incredibly hard to get bugs that get the physics wrong in materially interesting ways while still obeying conservation laws.
I once wrote a rarefied gas dynamics simulator (modelling a few thousand interacting particles--I was curious about some non-equilibrium thermodynamics questions) that conserved energy to +/-1 bit in double-precision (and which exercised the weird feature of some x86 processors that had something like 80-bit internal registers but did 64 bit double precision computations, and which allowed the garbage in the extra bits to contaminate the LSB, resulting in very slightly different behaviour in debug and release mode, which gave me fits for weeks.) It is just incredibly hard to get that level of conservation and still get the physics wrong.
And then there's semi-analytic solutions: to check that gas dynamics code I wrote a super-simple analog of the system in Perl based on approximate equations of motion, and got the same results. Because the underlying physics admits of different computational representations that are guaranteed to be the same if they are both correct and extremely unlikely to suffer from the same bugs you can have a very high degree of confidence in their correctness.
So no: the results of simulation are not wrong 97% of the time. I've worked on one experiment where the modelling was wrong, and which took three different computational approaches to sort out, but it's a rarity.
My feeling, based on experience, is these guys are onto something very interesting.
FWIW, this is a compiler error. Most x86 processors have 80-bit extended floats, which allow 64-bit "pow" to be computed in software with low error (among other benefits). Some compilers "helpfully" compile for 80-bit mode with some combinations of compile options. They should never do this unless it's specifically asked for using a single command-line option, partly for the reason you discovered: it totally messes with replicability. It also messes with implementations of "log1p", Kahan summation, and other high-precision algorithms like double-double arithmetic.
If you ever come across this again, submit a bug report.
As a software professional, I have been explicitly instructed to alter a program solely for the purpose of making the output more palatable for customers and investors, at the expense of real-world accuracy. And I did it, because as much as I dislike dishonesty, I also hate searching for new jobs and thoroughly enjoy sleeping under a roof and not starving.
Did the simulation that you wrote have a check for conservation of professional ethics?
You have a great advantage in that subatomic particles are unable to lie to you. Software developers have a capacity for deception exceeding even that of accountants, and we are sometimes asked to use it in unethical ways. One might think that there are reasonable limits, but we still have electronic voting machines that are mysteriously unauditable, and software trading agents programmed to automatically front-run institutional investors.
While the 97% figure was simply made up to mirror the ancestor post, it is possible that all those programs that are not accidentally wrong are intentionally wrong. In your case, you can rule out ill intent for the software you wrote yourself, but as there are potentially hundreds of millions of dollars in funding at stake for this fusion "discovery", I would not discount it for any simulation that suggests this device will work.
This is no longer the case.
http://en.wikipedia.org/wiki/Coal_power_in_the_United_States
Lockheed Skunk Works, on the other hand, is not.
They've been pushing the frontiers of engineering in areas that are very much constrained by physics since 1943, and succeeding. Many times.
For instance, the same argument applies to a wafer stepper or 'dreadnought class' surface mining equipment. Yet it seems unlikely they are able to commercially compete on both of those extremely different specialized kinds of machines. And I wonder if a fusion reactor would be any different.
Among people who have a common mindset, yes. But in general people don't like to take risks or expend insane efforts to make something happen. When they see others doing it, they like to stop them. Generally its because they don't want the regret 'They tried and got it, If I had ...' Or they are plainly jealous and can't stand some one else do progress.
Dropbox is a prime example of this effect: https://news.ycombinator.com/item?id=8863
The new system: Find a war torn area (perhaps one decimated by oil wars), dismantle their army and replace it with a wildly incompetent one. Make an earnest but fruitless attempt to train them (how humanitarian!). Give them American weapons (cha-ching) without actually solving any of the issues that were destabilizing the region. Local strive escalates to war, the incompetent army is crushed and their American weapons are seized. Use American owned and operated weapons (cha-ching) to bomb the seized American weapons back into the stone age (how humanitarian!). Rinse and repeat.
War machine get's their money, and the politicians get to pretend that they are only trying to help others.
I hope they have some novel ideas about neutron containment, though, otherwise you're right and this is project is not likely to yield the first economical fusion reactor.
obviously. The proposed reactor looks exactly like a great PhD thesis with honors - a novel field configuration proposed which allows to reach beta of one. The rest of the whole system is given only cursory treatment. In particular how about a "neutron absorbing blanket" in a business-jet size envelope?
McGuire is a top physicist - he is currently working on a compact fusion reactor at Skunk Works, which came out with the SR-71 Blackbird among other innovations.
Oh, did you mean, ones who had already succeeded in their top projects? Well, how do you think they got to succeed - by not doing it?
Shielding was mentioned, though not enough, but it's fairly trivial: if you add enough matter with a high neutron cross section (paraffin for example), and build the mechanical components out of things with a low cross section (iron, I think) it's not a problem. Plasma is the problem.
It's interesting, but "10 years off" is not much better than the standard "20 years off" promises of fusion research. As others have pointed out, controlled fusion has been 20 years in the future since 1950 or so. "1 year off" would be a lot more noteworthy. As it stands, this is just Lockheed informing us they have a controlled fusion program. Anyway, "nice press release, dudes."
So are refrigerators.
Plausible, since he had the experience.
Exactly! Just repeat keep repeating that process!
"As Tom McGuire, who is leading the Lockheed team, notes, however, the circular magnetic fields which coil around a tokamak’s doughnut become unstable if the plasma’s pressure is too high."
That being said, if they've genuinely cracked it, the game changes so much as to be unrecognisable.
They don't actually say it, but it sounds like they've only got computer models to work with at this point. Not very likely that they've actually cracked it.
I'm half joking, but I'd keep an eye out for more unusual energy related press releases, to see if that'll confirm that it's a media blitz aimed at the oil market etc.
According to this link[1] posted by another commenter, they create a "axisymmetric mirror by positioning zones of high magnetic field near each end of the vessel so that they reflect a significant fraction of plasma particles escaping along the axis of the CFR."
[1]: http://aviationweek.com/technology/skunk-works-reveals-compa...
LLNL scientists almost tested a similar device (see 'MFTF') but the project was cancelled in 1986 before it was turned on.
"It really is a vanishingly small amount of plasma that escapes from the device."
"What part of 'It is just like the Sun' did you not understand?"
I would guess that we have a much better understanding of plasma physics and faaaaar greater ability to model it now - that could lead to designs that can mitigate previously discovered issues with the concept.
We should be throwing more money at this...
If you haven't hung around talk-polywell.org before, you might want to. It's focused on the polywell but they seem to at least try to fairly evaluate all contenders.
New confinement techniques (NIF, this article, Helion, Polywell) are actually making real progress. So it's becoming less likely that an announcement like this is 100% vapor.
Put another way, we're getting to the point now where we have tools sufficient to actually know what the results will be. That, more than anything, is the benefit from the billions spent on tokamaks.
> "We also have a recirculation that is very similar to a Polywell concept," he adds, referring to another promising avenue of fusion power research. A Polywell fusion reactor uses electromagnets to generate a magnetic field that traps electrons, creating a negative voltage, which then attract positive ions. The resulting acceleration of the ions toward the negative center results in a collision and fusion.
It's great that they've scoured even the non-mainstream ideas and incorporated them.
Now this sounds way more serious than Andrea Rossi's saga. But I did get a lot tougher on my wait and see stand.
sigh To the extent this is true I suspect those "large fusion reactors" are tuned not so much for generating electricity and a great deal for annihilating whatever the carrying missile is pointed at.
But never mind fuzzy thinking at Reuters right now. This is amazing news if holds up. Fingers crossed.
> U.S. submarines and aircraft carriers run on nuclear power, but they have large fission reactors on board that have to be replaced on a regular cycle.
Submarines and carriers run on a fission reactor. And it powers everything - drives turbines for locomotion, electricity...
I'm well aware of the fission reactors in large military ships, but if there is any application of nuclear fusion on them then pretty much the only option today is thermonuclear warheads. It would be really nice if that's about to change.
http://en.wikipedia.org/wiki/High_beta_fusion_reactor
This is not the first time they have gone public with this - Charles Chase gave a talk at Google X last year, recorded and publicly-available:
Basically you catch electrons flying out of the plasma arc (where fusion is taking place), and ground them back into the plasma (which is positively charged).
Umm its largely theory at this point.
I do think what they are doing is interesting. If its like the Gas Dynamic Trap or Tandem Mirror it has promise, atleast from the fundamental physics point of view. Researchers in Novosibirsk had encouraging results in the last 5 years. They still have a long road ahead to get to fusion-relevant temperatures, but we are staying tuned to this one.
That phrase has been accurate for nuclear fusion in general for more than 50 years. The engineering and construction problems are immense.
As long as they remain secretive, they have no right to demand to be taken seriously.
A typical thermal power station has an efficiency below 50% for electricity generation, so the plant dissipates at least as much heat as it generates electrical power.
I wonder how you could get rid of 100MW of waste heat from a volume small enough to fit on a truck. That's a heat flux of more than a megawatt per square meter of surface area.
Or are my assumptions way off?
But what gets me is that they are burying the lead. No fusion reactor of any size has reached sustainability...so why is the story here talking about size at all? Small size would be a very nice added bonus; fusion reactors that don't consume more energy than they produce are earth-changing.
"But on the physics side, it still has to work, and one of the reasons we think our physics will work is that we’ve been able to make an inherently stable configuration.” One of the main reasons for this stability is the positioning of the superconductor coils and shape of the magnetic field lines. “In our case, it is always in balance. So if you have less pressure, the plasma will be smaller and will always sit in this magnetic well,” he notes."
As far as I understand this (IANAP), they're saying that smaller size = less pressure, and that helps their design to work (in theory).
That's exactly what I was thinking. They'd better call the Truck a submarine, though.
One can imagine these to be simple drop in replacements for existing coal plants with existing cooling infrastructure,which would be a huge environmental win in places where those are still built.
400km/h ~ 100m/s
air intake cross section ~ 1m^2
==> ~ 100m^3/s of air going through radiator
density of air ~ 1kg/m^3
==> ~ 100kg/s of air going through radiator
specific heat of air ~ 1kJ/(kg * degC)
==> 100kJ/(s * degC) == 100kW/degC
temperature difference between air entering and leaving the radiator ~ 10degC
==> 1MW
So handling 2.5MW waste heat doesn't seem out of the question from this analysis.
As another ballpark "upper bound" analysis, consider that copper is one of the most thermally conductive materials, with thermal conductivity ~ 400 Wm/(m^2 degC), let's round that up to 1kWm/(m^2degC).
Let's assume that there is a thermal conducting surface of 1m^2 (i.e. the surfaces of the pipes that interface with the radiators). Let's assume that the copper is 1mm thick (= 1m/1000). Let's see what temperature difference would be needed to transfer 1MW of heat across:
1MW == 1kWm/(m^2degC) * 1m^2 * (1000/1m) * deltaT degC
==> deltaT ~ 1 degC
which again doesn't seem out of the question.
As another ballpark "upper bound", the convective heat transfer coefficient for forced air is ~ 100W/(m^2degC), which means that assuming that the radiator fins are 100 degC above the air temperature, in order for the fins to transfer 1MW of power to the air, you would need an area of
1MW == 100W/(m^2degC) * 100 degC * area m^2
==> area ~ 100m^2 of surface area in the radiator, which doesn't seem unreasonable (a radiator 1m^2 area * 10cm deep, made up of thin plates spaced 1mm apart has this total surface area).
So they Veyron dissipating ~ 1MW in waste heat at 400km/h doesn't fail any of these basic sanity tests.
More complicated though is the interaction between the stages considered here. For example, how do we interface our 1m^2 of copper with our 100m^2 of radiator? Making the radiator fins thin lets us pack more surface area into the same volume, but also makes it difficult to keep the "edges" of the fins at a sufficiently high temperature so that they pull their weight transferring heat to the air: since the "copper tubing" has significantly less surface area, it only contacts (and thus transfers heat to) the radiator fins "sparsely".
Also consider that much of the size is due to the fan on the front (which is not part of the actual engine power plant), which makes the engine's area in the plane transverse to the axis of rotation seem larger.
However, jet engines have the advantage of burning their fuel directly in the air that is flowing through the engine, which results in an extremely rapid transfer of heat to the air compared to other (this is why 10 Boeing 747 engines == 1 GW coal/nuclear plant which is "buildings" in size).
See slide 25 (page 13) of http://ronney.usc.edu/AME436S13/Lecture1files/AME436-S13-lec...
Note that it converts ~100kW thermal into ~37-47 kW electric. It also has high air flow. I suspect that means that they are aiming to make their fusion reactor small enough that it can replace the burner section of the turbine.
Thermal transfer is still going to be a challenge, unless (Idea!) they are planning on spraying water into the airflow and using heat from neutron moderation in the water to provide primary heat transfer. Hmm, I wonder how much water you would need for 14 MeV neutrons? Let's see, half-value layer is around 10 cm, so if you threw a 40 cm thickness of water across a neutron flux, you'd absorb most of the heat (you could probably catch the rest in the duct casing). That's a lot of water in a pretty small space, but physically possible.
Note that the above is a seat-of-pants calculation and should not be taken as accurate by any means.
That's the standard issue joke. "Nuclear fusion has been just ten years away for the last fifty years"
It is so common as a joke I'm surprised the article didn't mention it.
10 - 765,000 results
15 - 9,730 results
20 - 793,000 results
25 - 8,750,000 results
30 - 709,000 results
35 - 4,700,000 results
40 - 472,000 results
45 - 10 results
50 - 493,000 results
Definitely not 45 years away.
They're more of a rounded (hence the clustering at or away from given numbers) measure of the remaining 'effort' versus 'difficulty'. Very likely there is some absolute time required (experiments take time to run), but throwing more people (and more importantly, more resources to run experiments and gather data) at the problem /would/ get to an end result faster (though how much faster is open to debate; it's sort of like asking how much effort does it take to win a top 30th percentile prize from a lottery).
Compare this with ITER, where they still don't know what material some fairly critical components can even be theoretically made of. It's just night and day.
the Skunk Works and EMC2 haven't even reached the stage where they would face the same issue of material - all of them would ultimately have to contain the same type of fast neutrons and there is no good known material to do it.
I'm sure someone at ITER has done the maths and figured out how long that core can last under operation before it becomes too brittle to keep the coils together, but I wouldn't be at all surprised if that was one of the reasons why ITER isn't designed for long-term power generation.
The problem is related to how you get rid of the post-fusion products. ITER is designed with divertor plates in the floor to scoop off the fusion ash and shunt them outside the core. My understanding is that these plates have to be a) solid, and b) capable of withstanding contact with absurdly high temperature plasma. There are some candidate materials which are hypothesised to be able to stand up to temperatures somewhere near what's required, but to my knowledge (which admittedly might be out of date) nothing's actually known to be suitable.
The reason I don't think the neutron absorption issue is such a problem here or on Polywell is because with a smaller reactor, replacing the vessel when it stops working is a far less terrifying prospect, even if you have to do so every few months. And even this is far less insane than some of the proposals for how you might do commercial laser fusion. That's just bananas.
Beyond that, you actually want some fast neutrons from the reaction to give you a tritium source.
They dismiss the concerns of the scientific community. Why shouldn't they? They're getting rich off of the ignorance of generals and venture capitalists.
It is however another great example that there is money going into lots of different fusion ideas. And that can only be a good thing as far as I am concerned.
[1] http://www.washington.edu/news/2014/10/08/uw-fusion-reactor-...
A year and a half later, they're apparently no closer to that goal.
http://blogs.wsj.com/venturecapital/2014/08/14/vc-funding-y-...
The team acknowledges that the project is in its earliest stages, and many key challenges remain before a viable prototype can be built
This falls under the xkcd 10 year plan:
"we haven't finished inventing it yet, but when we do, it'll be awesome"
I don't think so.
The difference is that fission is taking heavy elements, breaking them apart and using the released energy. Radioactivity, Thorium, Uranium, Plutonium, all the yucky stuff. Research has been going on for decades into making these reactors safer, and with breeder reactors and modern conventional designs that appears to have been achieved. Nevertheless, they appear on their way out anyway.
Fusion fuses together light isotopes and uses the energy thus released - they basically do what the sun does. And are clean. For various definitions of clean.
And if you're wondering how they are the complete opposite yet both work, it all pivots around iron. Copying from Wikipedia on iron:
> Its abundance in rocky planets like Earth is due to its abundant production by fusion in high-mass stars, where the production of nickel-56 (which decays to the most common isotope of iron) is the last nuclear fusion reaction that is exothermic.
And yes, that means that everything in this universe will one gigayear end up right at the pivot between fission and fusion, ever onwards oscillating further towards it. Our universe is ever tending tiwards irony. A pivot that we're probably going to see humanity go through too, but in a different way. Hopefully sooner rather than later.
This article is the cognitive equivalent of parrots squawking, because they don't even understand why the news actually is news.
People calling this a "typo" are giving too much credit. It could be a mistake, but the whole point of having an editor is to catch typos and mistakes! And it's a simple, short article!
But D-T is only the easiest form of fusion. Next up is D-D, which has much lower-energy neutrons. Helion is working on D-D combined with D-He3, producing only 6% of its energy as neutrons. And several outfits are hoping to manage proton-boron fusion, producing very little neutron radiation.
The AviationWeekly article mentioned D-T fusion for the Lockheed prototype and includes a diagram with the caption "blanket absorbs neutrons to breed fuel and transfer heat to turbines". This "blanket" will be tons of material that would be activated during operation and would have to be disposed of at EOL. Also, modern materials include many trace elements within the main molecular lattice such as cobalt, chromium, etc in steel and in some ways might be more difficult to process than used fuel rods.
I worked in the nuclear power industry decades ago and I don't recall the how the energy of fusion neutrons vs fission neutrons compared but I thought that in general fusion neutrons were significantly higher. Most power fission reactors also have neutron moderators which help to reduce the activation and embrittlement problems. Nevertheless, core components in fission reactors are already experiencing neutron embrittlement and has been a concern.
I'm not trying to be negative on fusion power but these overly optimistic reports have to be read with a critical eye.
I haven't seen any good quantitative comparisons of D-T waste to fission, now you've got me curious.
Totally agreed about the neutron embrittlement, I think that (IFMIF aside) this issue has just been brushed aside as a materials engineering 'detail' to be dealt with as part of commercialisation in a few decades when it might actually make the whole concept of using fusion for energy impractical.
Never mind, another linked article says that the injectors are only used for ignition.
No doubt that Skunkworks is world class... but claiming a "breakthrough in fusion energy" before a prototype has even been built is pretty bold of them.
So that would power 50k to 100k typical houses in the US... not bad!
Wouldn't the effect of its smaller mass be that the container will have to be replaced more often, more or less in the ratio of the masses of the machines?
I didn't find much to inspire confidence.
https://www.solveforx.com/moonshots/charles-chase-on-energy-...
"Until now, the majority of fusion reactor systems have used a plasma control device called a tokamak, invented in the 1950s by physicists in the Soviet Union. The tokamak uses a magnetic field to hold the plasma in the shape of a torus, or ring, and maintains the reaction by inducing a current inside the plasma itself with a second set of electromagnets. The challenge with this approach is that the resulting energy generated is almost the same as the amount required to maintain the self-sustaining fusion reaction."
I’m sure I’ve heard that somewhere before…
The mainstream magnetic confinement community has been very cautious about overhyping lately. Unfortunately, the over zealousness of groups like this and NIF saps credibility from them anyway.
If a researcher says a cool new technology should be
available to consumers in... -> what they mean is...
[...]
ten years -> "we haven't finished inventing it yet,
but when we do, it'll be awesome."These reactors will be similar to the Nimitz-class aircraft carriers and potentially only require refueling every 25 years through a process known as ROH.[1]
100MW capacity in the size of an international shipping container? The implications of this are massive if this technology can be brought to scale, and that is the key term - SCALE.
The cost of solar is plummeting and by the time fusion technology can produce 10% of our energy demand the cost of solar will be heading to $1/Watt, battery storage will be competitive and that is hard to beat even if the footprint is only a fraction of a solar farm.
[0] http://aviationweek.com/technology/skunk-works-reveals-compa... [1] https://en.wikipedia.org/wiki/Nimitz-class_aircraft_carrier#...
http://www.freepatentsonline.com/y2014/0301518.html
http://www.freepatentsonline.com/y2014/0301519.html
Both have publication date 10/09/2014. Maybe connected with the press release?
> Lockheed shares fell 0.6 percent to $175.02 amid a broad
> market selloff.
[0]: http://books.google.com/books?id=tEMQpbiboH0C&pg=PA15&lpg=PA...
Fusion Power GeekOut: http://www.dotnetrocks.com/default.aspx?showNum=1013
Fusion Power GeekOut #2: http://www.dotnetrocks.com/default.aspx?showNum=1022
Cold Fusion GeekOut: http://www.dotnetrocks.com/default.aspx?showNum=1037
http://www.extremetech.com/extreme/191754-cold-fusion-reacto...
Shouldn't the market be a little more excited about this?
As much as I want to believe it I can't find any evidence myself, either. At this point I'm pretty much at the "show me the over-unity reactor" phase. There's so many research paths to fusion right now that are all "promising", but until one of them actually builds something that works in the real world I'm not personally interested in hearing any more vague promises.
By all means fund them and keep working on them! I'm just not interested in the PR pieces any more. Give me a report about how it's working.
Skunkworks have as an organization an amazing engineering track record of implementing ground breaking technologies. I wonder what their current status is. Anyone have an inside scoop whether their game is still as sharp?
Lockheed has a market beta of 0.7 -- So it's correlated with the general market fairly strongly. On aggregate, if the market increases or decreases by 1%, you'd expect Lockheed to follow the market by 0.7%.
Today most of the major indices are down ~1%, Lockheed is down 0.4%, so you could attribute that 0.3% deviation from the expected number as reactor news. 0.3% of Lockheed's market cap represents about $170M today.
It's obviously not this straightforward, but if I were a shitty journalist, I could make the case that this is actually a pretty good result since commercialization will likely be a decade away, it will take a ton of resources and investment to get there, and there's a high chance of failure.
A shitty DCF with a ramp to $500M/year in R&D, 75% margins on sales, and a $10B/year business in perpetuity comes out to $170M NPV with a ~31% discount rate --- Not too unrealistic.
> U.S. submarines and aircraft carriers run on nuclear power, but they have large fission reactors on board that have to be replaced on a regular cycle.
Lockheed Martin is, indeed, saying they have a workable fusion reactor. Author of this article is the one that's confused.
Many companies have tried to set up a skunkworks since, but didn't have the guts to run it like Kelly did, and didn't get the results, either.
Or any other power plant for that matter.
"If it sounds too good to be true..."
Compare that to this: https://www.google.co.uk/maps/place/Barking+Power+Station,+B... google.co.uk
That's a 20 year old 1GW combined cycle gas plant, in a building roughly 50mx150m. Anything they can do to bring fusion plants smaller than ITER is going to help.
"Partners in industry and goverment". Translation: 10 years to product (but hey, prototype in 5) so please give us lots of dough. It's the technology of the future and always has been.
I suspect they are also much, much cheaper when you are talking about powers in the hundreds-of-megawatts range. I don't have specific data at hand to back that though. I never heard of any grid-level power generation being done with thermocouples.
[0] http://aviationweek.com/technology/skunk-works-reveals-compa...
(And then it rarely happens)
Ah science reporting.
Again, I could be wrong on my physics but as I understand it, fusion power is still a question of "is it even possible" whereas the hyperloop was more of a question about socioeconomic will.
There's lots of other problems too - I don't think they have a well-tested solution for adding fresh fuel and disposing of the fused products on an ongoing basis.
There have been steady incremental advancements in the field. I think your knee jerk reaction is coming from "cold fusion" which does have the problems you are talking about. Two very different fields.
The main issue with fusion is that it can't be weaponized and therefore doesn't have a nice military grant behind it. It lacks a Manhattan Project. It's probably always been "a few years from now" under the assumption of adequate funding.
The events following this announcement will probably be a good time to form a concrete opinion on fusion. It's being given a fair chance, so lets first see if it can prove itself.
This is promising stuff. Most of the other reactors have been Tokamak reactors - which are better suited to research and not practical applications, so we could be seeing some interesting results here.
RF and neutral beam heated steady reactor with very high mirror ratio and superconductors.
I can't see how heat energy is supposed to be flowing out of that plasma envelope yet the magnets are supposed to stay at near-zero temps?
I'm guessing this means that they will try and maximize profit rather than maximize cheap and clean energy for the entire world. That is a bit disappointing if true.
I don't understand what you expect? You want them to give it away for free? After paying very intelligent, expensive engineers decades worth of salaries to create it? You want them to create a fund where people can donate their hard-earned money for this noble goal? I'm sure you could give them a call with that idea, or you could create your own fund, even.
Or you could badger your "government" to fund such a project. Seeing as government is a very good analogy for a bunch of people giving their collective earnings for society-level goals. Let me know how that goes.
We always find a reason to go to war. Or it finds us and we return the favor.
Because a whole fleet of fusion air carriers, battleships, submarines and bombers versus a conventional army has plenty of implications in term of autonomy, reach, etc.
But on the other hand, there is a such demand for energy everywhere that it would really hard to morally ban all the civilians applications.
Energy use of the US (2011): 25,484 TWh Power needed: 2,900 GW = 25,484 TWh / 365 / 24 h * 1000 Number of 100 MW CFRs: 29,000
Civilian use will happen. The benefits are just much to great. There will be regulation and oversight for them. But you won't need one in every truck. It's overkill. As you can see from the above calculation 29 thousand CFRs could cover all the US energy needs. So there will be hundreds of thousands worldwide. It will be hard to keep all of them under control But this would basically solve all of humanities energy problems and decrease CO2 production, and destruction of the environment from mining immensely.
Having large amounts of energy available enables new weapon systems to become feasible: high powered lasers, coil guns and rail guns. They can be added to any air, land, or sea vehicle that's above the size of a small truck.
Ships are pretty large anyway and aren't as restricted as land or air vehicles when carrying big machinery. Aircraft carriers won't change so much. You can build them a little smaller and their defensive weapons might improve. Nuclear submarines otoh could be built as small as modern diesel powered subs like the Dolphin class.
You could build a drone with an extremely long loitering time. If it uses a laser or rail gun, it will also have lots of ammunition. Instead of carrying a couple of hellfire rockets and having to refuel after several hours it could stay in an area for months.
Cheap clean electricity means no-one needs to care about the Middle East for starters — most of the fighting there is superpower proxy fighting — e.g. Assad would be gone if not backed by Russia and China, so no Islamic State. No Oil, no Iraq war x2. No oil, no Hugo Chavez for that matter.
You can't have clean skies if everyone else is polluting. That is what makes pollution such a hard problem to solve. Even if USA cuts its pollution to zero, China alone can make up the difference.
But yeah, having access to this technology for everyone would be a serious game changer.
Edit: We are all riding the same spaceship... Its a serious flaw in thinking 'us vs them' when we are beginning to experiene some of the results in climate change.