Nuclear Fusion Breakthrough Confirmed: California Team Achieved Ignition. Research Continues (llnl.gov) 157
"A major breakthrough in nuclear fusion has been confirmed a year after it was achieved at a laboratory in California," reports Newsweek:
Researchers at Lawrence Livermore National Laboratory's National Ignition Facility (NIF) recorded the first case of ignition on August 8, 2021, the results of which have now been published in three peer-reviewed papers....
Ignition during a fusion reaction essentially means that the reaction itself produced enough energy to be self-sustaining, which would be necessary in the use of fusion to generate electricity. If we could harness this reaction to generate electricity, it would be one of the most efficient and least polluting sources of energy possible. No fossil fuels would be required as the only fuel would be hydrogen, and the only by-product would be helium, which we use in industry and are actually in short supply of....
This landmark result comes after years of research and thousands of man hours dedicated to improving and perfecting the process: over 1,000 authors are included in the Physical Review Letters paper.
This week the laboratory said that breakthrough now puts researchers "at the threshold of fusion gain and achieving scientific ignition," with the program's chief scientist calling it "a major scientific advance in fusion research, which establishes that fusion ignition in the lab is possible at the National Ignition Facility."
More news from this week's announcement by the Lawrence Livermore National Laboratory: Since the experiment last August, the team has been executing a series of experiments to attempt to repeat the performance and to understand the experimental sensitivities in this new regime. "Many variables can impact each experiment," Kritcher said. "The 192 laser beams do not perform exactly the same from shot to shot, the quality of targets varies and the ice layer grows at differing roughness on each target...."
While the repeat attempts have not reached the same level of fusion yield as the August 2021 experiment, all of them demonstrated capsule gain greater than unity with yields in the 430-700 kJ range, significantly higher than the previous highest yield of 170 kJ from February 2021. The data gained from these and other experiments are providing crucial clues as to what went right and what changes are needed in order to repeat that experiment and exceed its performance in the future. The team also is utilizing the experimental data to further understanding of the fundamental processes of fusion ignition and burn and to enhance simulation tools in support of stockpile stewardship.
Looking ahead, the team is working to leverage the accumulated experimental data and simulations to move toward a more robust regime — further beyond the ignition cliff — where general trends found in this new experimental regime can be better separated from variability in targets and laser performance. Efforts to increase fusion performance and robustness are underway via improvements to the laser, improvements to the targets and modifications to the design that further improve energy delivery to the hotspot while maintaining or even increasing the hot-spot pressure. This includes improving the compression of the fusion fuel, increasing the amount of fuel and other avenues.
"It is extremely exciting to have an 'existence proof' of ignition in the lab," said Omar Hurricane, chief scientist for the lab's inertial confinement fusion program. "We're operating in a regime that no researchers have accessed since the end of nuclear testing, and it's an incredible opportunity to expand our knowledge as we continue to make progress."
Thanks to long-time Slashdot reader hesdeadjim99 for sharing the news.
Ignition during a fusion reaction essentially means that the reaction itself produced enough energy to be self-sustaining, which would be necessary in the use of fusion to generate electricity. If we could harness this reaction to generate electricity, it would be one of the most efficient and least polluting sources of energy possible. No fossil fuels would be required as the only fuel would be hydrogen, and the only by-product would be helium, which we use in industry and are actually in short supply of....
This landmark result comes after years of research and thousands of man hours dedicated to improving and perfecting the process: over 1,000 authors are included in the Physical Review Letters paper.
This week the laboratory said that breakthrough now puts researchers "at the threshold of fusion gain and achieving scientific ignition," with the program's chief scientist calling it "a major scientific advance in fusion research, which establishes that fusion ignition in the lab is possible at the National Ignition Facility."
More news from this week's announcement by the Lawrence Livermore National Laboratory: Since the experiment last August, the team has been executing a series of experiments to attempt to repeat the performance and to understand the experimental sensitivities in this new regime. "Many variables can impact each experiment," Kritcher said. "The 192 laser beams do not perform exactly the same from shot to shot, the quality of targets varies and the ice layer grows at differing roughness on each target...."
While the repeat attempts have not reached the same level of fusion yield as the August 2021 experiment, all of them demonstrated capsule gain greater than unity with yields in the 430-700 kJ range, significantly higher than the previous highest yield of 170 kJ from February 2021. The data gained from these and other experiments are providing crucial clues as to what went right and what changes are needed in order to repeat that experiment and exceed its performance in the future. The team also is utilizing the experimental data to further understanding of the fundamental processes of fusion ignition and burn and to enhance simulation tools in support of stockpile stewardship.
Looking ahead, the team is working to leverage the accumulated experimental data and simulations to move toward a more robust regime — further beyond the ignition cliff — where general trends found in this new experimental regime can be better separated from variability in targets and laser performance. Efforts to increase fusion performance and robustness are underway via improvements to the laser, improvements to the targets and modifications to the design that further improve energy delivery to the hotspot while maintaining or even increasing the hot-spot pressure. This includes improving the compression of the fusion fuel, increasing the amount of fuel and other avenues.
"It is extremely exciting to have an 'existence proof' of ignition in the lab," said Omar Hurricane, chief scientist for the lab's inertial confinement fusion program. "We're operating in a regime that no researchers have accessed since the end of nuclear testing, and it's an incredible opportunity to expand our knowledge as we continue to make progress."
Thanks to long-time Slashdot reader hesdeadjim99 for sharing the news.
"Unity" (Score:5, Interesting)
There's many kinds of unity, I suspect they are using the simplest one for this. There's greater than the input power to the 192 complicated lasers, there's greater than the input power to the facility, and there's greater than the power needed to fabricate targets and replacement laser parts, from mining raw materials to landing finished parts at NIF. Does anyone have that last number?
Not even that (Score:2, Informative)
While reading TFSes from these "editors" is generally futile, there is the abstract of the paper:
Th
They're slowly mapping a way forward. (Score:3)
I don't buy the hype about replacing the whole energy system: Fusion is way too complex for that. But it'll open up some exciting possibilities.
Re:They're slowly mapping a way forward. (Score:5, Insightful)
While I agree with the sentiment it could absolutely replace everything. It's complex NOW but doesn't mean to say it will remain complex. Thousands of technologies have started off as complicated messes that required hugely complex engineering but are now ubiquitous and well understood (not by the masses but by those that matter).
As a (somewhat trite) example think of the complexity of something like a modern CPU and how advanced and small they've become. Back then they were room filling, slow complicated messes of valves and wires. Only a handful of people in the world understood them and fewer still could build one. I bet if you went back 80 years ago and suggested something as powerful and complex as the CPU in your phone existed in 80 years they'd laugh at you. More so if you told them there were literally BILLIONS of these chips and everyone was carrying them around in their pocket for $200.
Now fusion is way more complex than those early computers, of course, but complexity often becomes normality over time.
CPUs are small, but still horrendously complex (Score:4, Insightful)
Holding up a CPU as a technology that used to be giant and clunky that is now "everyday", as an analogy to what fusion plants could become, is horribly wrong.
First, CPUs are still supremely complex, difficult machines that require tremendous alliances of multiple industries to build. The current complexity of a CPU far exceeds that of the mainframe computer of yesterday.
The only reason that CPUs are economical AT ALL is that once built, they are then replicated in thousands or millions or billions--as you pointed out.
You will *never* get that kind of economy of scale going for fusion plants based on lasers.
You know what does scale though? Solar panels and batteries.
A better analogy would be the initial research fission plants compared vs. the commercial nuclear plants producing power today. And you'll notice that even today the commercial nuclear plant is an expensive, somewhat rare, and complicated beast.
Analogies to IT hardware don't work. (Score:2)
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Fusion is way too complex for that
I'm sure everyone's grandfather said that about these fangled "chip" things replacing their vacuum tubes, to say nothing of the insane complexity of the automobile compared to attaching a piece of wood to a horse and slapping it on the backside.
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Calling someone "unoriginal"...how original. (Score:2)
My mistake. (Score:2)
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Re:"Unity" (Score:5, Informative)
Yeah; the days where major newspapers had science bureaus to cover this kind of thing are long past; clearly the reporters covering this are starting from near ignorance on the topic. You pretty much have to *guess* what's actually been achieved.
I'm guessing they managed to reach "scientific breakeven", which is when the power released by fusion for some period equals or exceeds the power being used to heat the fuel. This is a somewhat arbitrary milestone, because most of that energy is, at present, impossible to capture for useful purposes. Q >=1 is really no practically different than the old record of Q=0.7. 1.0 here is just an arbitrary higher number.
The real practical breakthrough will be "engineering breakeven", which is when a facility produces enough *usable* power to run itself.
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Does anyone have that last number?
A suffusion of yellow.
Re: "Unity" (Score:2)
Re:"EROEI" (Score:3)
There's many kinds of EROEI, I suspect they are using the simplest one for this. There's greater than the input power to the 192 complicated lasers, there's greater than the input power to the facility, and there's greater than the power needed to fabricate targets and replacement laser parts, from mining raw materials to landing finished parts at NIF. Does anyone have that last number?
By your specification "Unity" is the same as Energy Return On Energy Invested. There is Nuclear Energy and the Second Law [stormsmith.nl] which is an end to end study of Fission base Nuclear Power answering the criteria you specify to a similar complexity. IIRC CERN, amongst other recognized institutions, is one of the peer reviewers of this study and it is used by the European parliament to frame energy policy.
However for Fusion base Nuclear power it's unlikely because the energy system is still a prototype and the va
There's still a long way to go (Score:5, Informative)
They're either going to have to make a much bigger bang:
And/or they're going to have to make each shot a whole lot cheaper:
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Wow, nice command!
Never knew about that one!
Thanx!
cold Fussion (Score:3, Interesting)
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Chief Scientist Omar Hurricane ? You must be shitting me.
Re: cold Fussion (Score:2)
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Not that surprising: remember how many people here were wild gems of the EM drive despite it being a perpetual motion machine in all but name. No reasoning could get through to them because they desperately wanted to believe.
You know Newton was wrong therefore all of modern physics is wrong in just the right way for the thing I want to be true. Never mind that physics had a decent track record of actually working, including Newtonian mechanics.
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including Newtonian mechanics.
Newtonian mechanics are excellent at explaining things in the scale and scope of Newtonian mechanics, and is worthless beyond that. I remind you that a grand unifying theory hasn't been found so all physics is still "wrong" to a certain extent.
There's a reason the EM drive was actually replicated and tested by scientists rather than just being fobbed off as nonsense like cold fusion and normal perpetual motion machines are. It was ultimately determined to be a perpetual motion machine in all but name, but t
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It was ultimately determined to be a perpetual motion machine in all but name, but the actual proof for that took months.
EM drive was most certainly a classic example of pathological science yet it was never a perpetual motion machine. It required energy to operate and pushed magical aether in an equal and opposite direction.
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Thing is it was a perpetual motion machine, but a hidden one.
Most perpetual motion machines require energy and are so described as"over unity", as in they need energy in, but give back more. If they worked. Which they don't.
The EM drive wasn't supposed to be, but if you hooked up something to turn some of its kinetic energy back into electrical energy you get enough to run it with plenty to spare. That makes it a perpetual motion machine.
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The EM drive wasn't supposed to be, but if you hooked up something to turn some of its kinetic energy back into electrical energy you get enough to run it with plenty to spare. That makes it a perpetual motion machine.
EM drive is no more a perpetual motion machine than an amplified photon thruster. The only way one can fool themselves into thinking energy is being created is by failing to draw a big enough box to account for the magical aether.
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amplified photon thruster[...]magical aether.
I am seriously confused as to what your point is now and I honestly can't tell if you're criticising my reasoning or the reasoning behind the EM drive. So, let me wind back to the beginning and state my argument, which is a proof by contradiction:
1. An working EM drive produces more thrust than a photon thruster
2. Therefore one can build an energy harvesting device and it would yield energy over unity
3. That's a perpetual motion machine/violation of thermodynamic
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I am seriously confused as to what your point is now and I honestly can't tell if you're criticising my reasoning or the reasoning behind the EM drive. So, let me wind back to the beginning and state my argument, which is a proof by contradiction:
1. An working EM drive produces more thrust than a photon thruster
2. Therefore one can build an energy harvesting device and it would yield energy over unity
You appear to be claiming producing more thrust than a photon thruster violates conservation of energy however exactly this has been demonstrated many times over in the real world.
"For example, 10,000 times recycling of photons with 15 kilo-watt input laser power, which can be delivered by a 100 kW solar panel would produce up to 1 N of photon thrust"
https://www.nasa.gov/spacetech... [nasa.gov]
https://www.nasa.gov/sites/def... [nasa.gov]
Interplanetary photonic railways:
https://ykbcorp.com/photonic-l... [ykbcorp.com]
3. That's a perpetual motion machine/violation of thermodynamics/violation of the symmetry of physics.
4. Since 3 is impossible it therefore follows that a working EM drive is impossible.
So if you build an amplifi
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You appear to be claiming producing more thrust than a photon thruster violates conservation of energy
Without reaction mass, just to clarify. Otherwise that would rule out chemical rockets, which would be absurd.
however exactly this has been demonstrated many times over in the real world.
What your links show is a system with a spacecraft and a much larger reaction mass coupled by lasers. Still an interesting idea, but it isn't related to the EM drive because the EM drive has no reaction mass.
So if you build
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Sigh.
Newtonian mechanics isn't wrong, it's incomplete. It's right enough that it's used for pretty much all human endeavours except pretty much GPS and semiconductors. It's never going to be overturned at human sales and energy levels.
It was trivial to show the EM dive was a perpetual motion machine. The authors missed that, but given their tenuous grasp of physics, that's not surprising.
It was also trivial to show the maths was wrong because the theory used to derive it had already been proven mathematical
Not surprised that it's inertial confinement. (Score:3, Informative)
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By far the most likely to go anywhere.
Not many people agree with you. Power generation is not part of NIF's mission. It is a weapons research facility.
How could this possibly scale? They needed billions of dollars of equipment and infrastructure and days of setup time, resulting in the energy output of two teaspoons of gasoline.
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NIF's mission is ICF, and ICF is one of the methods being pursued for power generation, ergo NIF is part of that arena even if the source of funding is military.
NIF is a scientific apparatus, not
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You'll observe that opponents to fusion have no problem moving a few goalposts when objectives are actually reached. I agree, Q>=1 was long-touted as an impossible dream by skeptics. Now it has been achieved, those same skeptics are saying it doesn't matter anyway.
Of course working fusion will be the end of all energy problems, although you ideally want a nearby fission reactor to be able to jump-start the damn thing if you need to power it down for any reason.
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Why does the backup to a fusion reactor need to be fission? Why can it not be another fusion reactor, similar to how fission plants have multiple reactors operating at the same time? Or pumped hydro? Or a flywheel?
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If a fusion reactor is down, it's likely because the grid can't handle that much power, and the most common causes will be line failure, followed by lack of demand. In that case, the backup fusion reactor would be shut down as well.
Flywheel won't generate enough power, you need a huge initial input for mag fields, computers, and cooling system. Even a single hydro dam is unlikely to generate enough. A fission reactor - perhaps a mini nuke - could be shut down the rest of the time, only running for restart o
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It sounds like we're always going to need a backup source of power then, to bootstrap the fusion reactors when they get taken down for any reason -- capacity, maintenance, errors, what have you. I am slightly reminded of diesel fuel vs. gasoline. There's more energy in the diesel fuel, but it's a lot harder to get it to ignite.
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None of that really amounts to a downside for fusion; unless you're trying to say "solar is cheaper and has failed to be the end to all energy problems, so a more expensive solution doesn't stand a chance," you haven't really dismissed fusion. I'm sure there were coal execs making the same sorts of claims about fission seventy years ago.
As I understand it, solar power does pose some problems of its own. Panel manufacture requires a lot of very... rapacious mineral extraction that isn't doing the environment
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* Passive rather than active.
* Smaller unit cost.
* Radically simpler unit technology.
* Quicker to make a complete system.
* Far more practical diversity in approaches.
* Far more scalable, both up and down, in both individual unit dimensions and whole systems, fitting more spaces and applications.
* Faster evolutionary feedback.
* Quicker to sca
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So ... (Score:5, Funny)
The serious answer to the 20 years thing (Score:2)
I forgot where I read it, but I think it was an article by a major fusion researcher who has been in it since the early years. His claim is that the "20 year" prediction was based on the condition of "...if current levels of funding in relation to the economy continues" Of course, it didn't, because people generally have short attention spans, and if it doesn't get immediate results, it's not worth doing. The basic model was that if the funding were cut in half, it would take twice as long (at least). How
Re: The serious answer to the 20 years thing (Score:2)
Here is a relevant graph [external-preview.redd.it].
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More likely than not. The first fission reactor was the very end of 1942. The S1W reactor did its first serious power run in 1953.
If replacing the boiler in a well understood steam plant with a reactor took 10 and a half years then I would expect it to take longer to get power on the grid from fusion.
https://en.wikipedia.org/wiki/... [wikipedia.org]
https://en.wikipedia.org/wiki/... [wikipedia.org]
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MIT should have SPARC running in 2025. If it works as expected, the fusion problem is AFAIK solved
Science Expirement (Score:5, Interesting)
Laser fusion is not a viable path to the sustained fusion we will need for a working reactor. The NIF is a physics experimental platform on the same scale as a super collider. It is important research project because we need to understand what happens at the moment of fusion but it will not lead to a practical reactor.
Great news for the military (Score:3)
Re: Great news for the military (Score:2)
Ya, and what happens someone loses the keys? They will have to Hotwire the thing and we know where that ends⦠bottom of a canal somewhere
Re: Science Expirement (Score:3)
I'm no physicist, but does the output of these experiments give the boys at ITER more information in order to be successful in their endeavors? Seems like people are quick to shit on this, rather than accept that some gained knowledge from these efforts may apply to other designs meant to be more applicable to energy production...
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My understanding is that the national ignition facility has a lot more to do with research related to (thermo)nuclear weapons. They can't test above ground anymore, so they simulate things in supercomputers and run dedicated experiments of parts of the processes that would occur inside these bombs. This is one of those experiments that provides new data as to how fusion starts and progresses.
As for practical fusion, I think Commonwealth Fusion Systems is among the contenders more likely to reach practical
Well, that is some good news... (Score:2, Insightful)
The whole project was often seen as as way to keep some very, very useful nuclear engineers and scientists from getting bored and leaving the lab. The chosen site (dry, windy, dusty) and initial build plan was just a nightmare. Optic components arriving way before there was a place to even store them, long arguments about what needed to be in house and what didn't (hint, leave control systems to professionals) and so on. Still a way better use of money than most military projects, though. Funny how that nev
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Still a way better use of money than most military projects, though.
You know you have a boondoggle when the main justification is pointing at other expenditures that are even stupider.
You know what this means? (Score:3)
Practical fusion energy is only 10-15 years away now!!
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I'd say more like 5-10 years away. We need to be building the infrastructure that can handle the kind of power output expected from a fusion reactor as it's going to be a bit late to start AFTER we have such reactors.
Once ubiquitous, how long before.. (Score:3)
Ignition definition (Score:5, Interesting)
They keep changing the definition of ignition. First, When the NIF got funded, ignition was projected as when the reaction produced more energy than the lasers consume from the power plant. When the realization dawned that that was hard,, ignition was redefined as when the energy produced from fusion exceeds the energy of the UV lasers (1.9 megajoules). Now they made the definition to be exceeding the x-ray energy (250kJ) deposit on the target pellet by the hohlraum.
Everyone agrees: Ignition occurs when the energy deposited by products of the thermonuclear burn during one confinement time equals the energy required to heat the plasma to thermonuclear burn temperatures.
To me, that sounds like the energy needed to vaporize the hohlraum into plasma.
Now they finagled it to mean the energy of the X-rays wtf?
Reference: https://www.physics.utoronto.c... [utoronto.ca]
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There's basically three "break even" levels to consider:
1) Physics breakeven - when the reaction releases more energy than was absorbed by the fuel to make it fuse - that's what they seem to have done here.
2) Engineering break even - when the reactor generates more energy than was used to power it, including the power needed for ignition and confinement, and conversion losses to convert the resulting heat to electricity. They are still far from this, probably a decade or more.
3) Economic break even - when t
Re: Ignition definition (Score:2)
Physics breakeven is nonsensical. If you want to play that game, physics breakeven has been achieved for decades as there are hotspots within any ICF plasma where fusion is occurring. For example in laser fusion, it happens due to diffraction. You can claim the energy released within the hotspot is greater than the energy directly compressing the hotspot. In fact everywhere fusion occurs can be faux-claimed as physics breakeven. In 1997, when the NIF was funded, the National Academy of Science defined igni
Two things we need (Score:5, Interesting)
First, there's almost no funding of fusion research. The sum total of all that governments of the world have put into fusion since the 1960s is equal to how much they put into fossil fuels every 3 days. Fossil fuels can spare 3 days' of subsidies, given their profit margins, which would more than double the available money in fusion research. This may be sufficient to push fusion over the line.
Second, there's the infrastructure. No country has a grid capable of handling the kind of power levels fusion is likely to produce and substations take time to build. We need to be building out the infrastructure now and upgrading what exists to be able to support this new technology, or we'll acquire fusion but be unable to use it for 10-20 years.
Better infrastructure won't hurt, anyway. It'll make the grid more resilient to terror attacks and extreme weather. (Most here remember when the entire northeast of the US suffered a three day blackout due to a single branch on the wires. The changes since then have been minimal and aren't adequate for the world we live in today. The grid simply isn't currently capable of handling both the modern political atmosphere and the sort of weather that we are now very likely to get on an annual basis.)
I see (Score:2)
"Researchers at Lawrence Livermore National Laboratory's National Ignition Facility (NIF) recorded the first case of ignition"
They call themselves an 'Ignition Facility' and never had an ignition before?
Respect!
Milestones (Score:2)
There have been fusion milestones seemingly every few months for years, so I tend to lump them in with "battery breakthroughs", where "scalable technology is only X years away!"
But this actually does seem like major milestone/breakthrough. I wouldn't go as far as predicting when we'll have commercial power generation, but kudos to these scientists for getting ignition.
should helium overproduction be concern? (Score:2)
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No, helium overproduction isn't an issue. First, it's useful for more purposes that we're currently putting it to, because other gases are more common and can do the job -- like argon for welding. Argon, being 1% or so of the atmosphere, is probably always going to be popular as an inert gas, but helium works too. Helium can also be stored in the same reservoirs currently used to hold natural gas. That's where a lot of our helium supply comes from anyhow -- they're alpha particles from radioactive decay tha
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That falls under the heading of cryogenics, as does JWST.
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No. The amount of helium produced by fusion in any foreseeable future is not going to be enough to solve the global helium shortage.
What's new, exactly? (Score:2)
Can't be bothered to read TFA.
But I thought tokamaks were already igniting, for decades, and so were fusors. The latter were capable even of sustaining. And the TFA design still hasn't proved sustained reaction at break-even so... impressive, but hardly a "breakthrough"?
Can someone clarify?
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Not sure about today's achievement, but at least for tokamak, I know they ignite but have the problem is neutron confinement.
Awaiting the time here is enough energy for aneutronic fusion like Boron+Hydrogen, the Tokamak produce high energy neutrons. They do not care about electromagnetic confinement. and will hammer the device to death. That is a no-go for actual electricity production.
Wendelstein 7-X is the more interesting approach (Score:2)
Therefore, I consider the Wendelstein 7-X [wikipedia.org] experiment much more interesting - their Stellarator has progressed to almost continuous confinement of plasma that reaches the relevant temperatures.
How did they do it? (Score:2)
Re:Hydrogen ... (Score:5, Insightful)
Most fusion concepts use deuterium, which is a lot rarer than hydrogen, but still doesn't represent a major problem. Tritium can be generated from Lithium in the fusion reactor itself.
there are lots of potential problems with practical fusion, but this one isn't concerning.
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I'm not sure that tritium can be generated in a laser-pulse ignition. Everything I've seen has been based around magnetic confinement.
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I'm not sure that tritium can be generated in a laser-pulse ignition.
Why not? You are going to get neutrons either way.
A lithium blanket will absorb the neutrons so they don't damage the reactor structure and put them to good use by generating tritium.
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Well, some of the laser ignition images I've seen show light being blasted in from several directions at once, which makes putting the lithium blanket in place a bit questionable.
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The amount of energy fusion releases per kilogram of hydrogen is on the order of a million times more than it takes to separate the hydrogen from water, ...
Thanks. I suspected that, but thought I'd ask anyway.
Re: Hydrogen ... (Score:3)
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the only fuel would be hydrogen, ...
This is false. DT fusion reactors also consume lithium. Lithium is used to breed tritium.
And where are we going to get all the required hydrogen
Are you serious? The oceans contain a hundred quadrillion tonnes of hydrogen.
The fuel is the easiest part.
You can buy deuterium from Amazon. I bought some for my kids to play with. We made ice cubes that sink.
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The oceans contain a hundred quadrillion tonnes of hydrogen.
Of course, but that hydrogen needs to be split from the water molecules. I was wondering about the energy required to generate enough hydrogen (ffrom water or fossil fuels) to run the fusion reactors. Someone else noted that the fusion process generates more than enough energy per unit of hydrogen (deuterium) that this isn't a concern...
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I think you did not buy Deuterium, but heavy water. ...
And I doubt ice from heavy water is heavy enough to sink
Re:Hydrogen ... (Score:4, Informative)
I think you did not buy Deuterium, but heavy water.
Sure, but electrolysis is easy if you want D2 gas.
And I doubt ice from heavy water is heavy enough to sink ...
Heavy water ice sinks: Normal ice has a density of 0.917. So a straight calculation is that D2O has a density of 0.917 * 20/18 = 1.02. But that is wrong. The actual density is 1.05 since deuterium has shorter molecular bonds to the oxygen, so the crystal structure of the ice is tighter.
Heavy water ice freezes at a higher temperature, about 3.8 C. So if you put a drop on your finger and touch a normal-ice cube, the heavy water will freeze and bond your finger to the icecube.
Another fun experiment is to put a drop of D2O on your tongue. It has a sweet taste.
If you have kids, you should buy them some D20. Also, some gallium and metallic sodium. Wear eye protection with the sodium.
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You're basically confusing/conflating two completely different things.
One's burning 2H2 + O2 => 2H2O, which produces in an absolutely ideal situation the same amount of energy as it takes to split 2H2O => 2H2 + O2.
The other is annihilating the H2 (or H3 preferably) into He, which follows the by now well know E=MC2.
The amount of energy released by the second is a rather large order of magnitudes larger.
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nd where are we going to get all the required hydrogen --
Whatever happened to using He3 for this? The promise was we could mine the moon for unlimited quantities of this.
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Whatever happened to using He3 for this?
We have been working on DT fusion for half a century, and He3 fusion is WAY harder than DT fusion. He3 requires much higher temperatures and has lower energy production.
The only advantage is that it is aneutronic, but that isn't a big deal. In a DT reactor, the neutrons are absorbed by lithium.
The promise was we could mine the moon for unlimited quantities of this.
No, He3 is very rare, even on the moon. It is just slightly less rare there. Meanwhile, the oceans contain quadrillions of tonnes of deuterium.
TL;DR: He3 fusion is totally unrealistic.
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I expect they could manufacture it themselves
Why bother? They are only using small quantities, and they can buy all they need from Amazon for $10.
99.92% D2O, $9.95. [amazon.com]
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Was that meant to be a joke?
Have you ever seen photos of hydrogen bomb explosions? Massive amounts of energy produced by a small amount of hydrogen.
Perhaps you should worry about the Sun running out of Hydrogen?
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Well, much of the hydrogen fused in a nuclear weapon actually comes from the fission of the Lithium in the Lithium Deuteride (the other part is from the deuterium, obviously).
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Which is enough energy to provide for about 20 million people for one day. Multiply that by about 15, and then do that every single day. And that is just for the USA.
It adds up
Historically people have mistaken an abundance of supply for an effectively inexhaustible one before. The costs for such misjudgment getting paid by their descendants sometimes many generations later.
W
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No worries, the deuterium (aka 'heavy hydrogen' from water they'd be using is only one atom out of 3,200 molecules of water. We can't fuse ordinary hydrogen in these devices, you need something the size of star to do that. Earth's water supply is safe!
A mere cubic mile of water has enough deuterium to power the Earth's energy supply for 1,500 years. The ocean has a lot of cubic miles, 300 million of them... the Earth won't last long enough for us to use all the Deuterium in the ocean even if we only
Re:Sounds great and all.... (Score:4, Informative)
We can't fuse ordinary hydrogen in these devices, you need something the size of star to do that.
Pedantic nitpick: You can fuse ordinary hydrogen with boron in an aneutronic fusion reaction [wikipedia.org].
B11 + H => 3He + 8.7MeV
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We can't do that either.
We can't do it with plasma, but we can do it by shooting accelerated protons into a solid chunk of boron.
Certainly, it is impractical for power generation. That is why it is a pedantic nitpick.
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What you brought up is not relevant at all and was pointless.
Exactly. It is pedantry, which is what I said.
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99% of all the water on the planet is believed to be in the mantle and isn't doing much of anything.. We've hydrogen to spare.
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71% of Earth is covered in water. No sane person thinks fusion power can make a dent in that.
Space is full of water and hydrogen too though, they're the most common things that can be.
Re: Again behind.. (Score:2)
Uh no they did not.
Re: Again behind.. (Score:2)
Got proof? A reference link?
Re: Again behind.. (Score:2)
Thereâ(TM)s nothing on Google stating your BS sorry. You lied.