
In Fusion Breakthrough, US Scientists Reportedly Produce Reaction With Net Energy Gain (independent.co.uk) 184
"U.S. scientists have reportedly carried out the first nuclear fusion experiment to achieve a net energy gain," reports the Independent, "a major breakthrough in a field that has been pursuing such a result since the 1950s, and a potential milestone in the search for a climate-friendly, renewable energy source to replace fossil fuels."
The experiment took place in recent weeks at the government-funded Lawrence Livermore National Laboratory in California, where researchers used a process known as inertial confinement fusion, the Financial Times reports, citing three people with knowledge of the experiment's preliminary results. The test involved bombarding a pellet of hydrogen plasma with the world's largest laser to trigger a nuclear fusion reaction, the same process which takes place in the sun.
Researchers were able to produce 2.5 megajoules of energy, 120 per cent of the 2.1 megajoules used to power the experiment. The laboratory confirmed to the FT it had recently conducted a "successful" experiment at the National Ignition Facility, but declined to comment further, citing the preliminary nature of the data....
"Scientists have struggled to show that fusion can release more energy out than is put in since the 1950s, and the researchers at Lawrence Livermore seem to have finally and absolutely smashed this decades-old goal," Arthur Turrell, deputy director of the UK Office for National Statistics, wrote on Twitter on Sunday. "This experimental result will electrify efforts to eventually power the planet with nuclear fusion — at a time when we've never needed a plentiful source of carbon-free energy more!"
But "the resources needed to recreate the reaction on the scale required to make fusion practical for energy production are immense," reports the Washington Post: More importantly, engineers have yet to develop machinery capable of affordably turning that reaction into electricity that can be practically deployed to the power grid. Building devices that are large enough to create fusion power at scale, scientists say, would require materials that are extraordinarily difficult to produce. At the same time, the reaction creates neutrons that put a tremendous amount of stress on the equipment creating it, such that it can get destroyed in the process. And then there is the question of whether the technology could be perfected in time to make a dent in climate change.
Even so, researchers and investors in fusion technology hailed the breakthrough as an important advancement.
Researchers were able to produce 2.5 megajoules of energy, 120 per cent of the 2.1 megajoules used to power the experiment. The laboratory confirmed to the FT it had recently conducted a "successful" experiment at the National Ignition Facility, but declined to comment further, citing the preliminary nature of the data....
"Scientists have struggled to show that fusion can release more energy out than is put in since the 1950s, and the researchers at Lawrence Livermore seem to have finally and absolutely smashed this decades-old goal," Arthur Turrell, deputy director of the UK Office for National Statistics, wrote on Twitter on Sunday. "This experimental result will electrify efforts to eventually power the planet with nuclear fusion — at a time when we've never needed a plentiful source of carbon-free energy more!"
But "the resources needed to recreate the reaction on the scale required to make fusion practical for energy production are immense," reports the Washington Post: More importantly, engineers have yet to develop machinery capable of affordably turning that reaction into electricity that can be practically deployed to the power grid. Building devices that are large enough to create fusion power at scale, scientists say, would require materials that are extraordinarily difficult to produce. At the same time, the reaction creates neutrons that put a tremendous amount of stress on the equipment creating it, such that it can get destroyed in the process. And then there is the question of whether the technology could be perfected in time to make a dent in climate change.
Even so, researchers and investors in fusion technology hailed the breakthrough as an important advancement.
How would NIF be sustainable anyway? (Score:3, Interesting)
When your means of causing fusion is to put an exquisite little fuel pellet somewhere and then zap it with huge amounts of laser energy... how do you sustain that? Rig up a mechanism to keep putting fuel pellets there? A mechanism that won't be destroyed by all the energy? Tokamaks etc seem to be a little more aimed at creating a reaction that's not only contained but sustained.
Re:How would NIF be sustainable anyway? (Score:5, Insightful)
It's not but it was never meant to be an energy generator or even really built for the purposes mainly of even studying energy generation, it was built to do nuclear weapon simulation for weapons maintenence and some general science in there as well.
ITER is the next actual phase for fusion.
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Probably not.
ITER really suffers from lack of thinking. It's a build it bigger and maybe it will work project. The problem is at that scale and capital cost we are no longer talking about cheap energy but really expensive energy.
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ITER is a demonstrator of the best known design we have working right now. Maybe other designs that have potential like the MIT one can catch up but ITER is the next largest step for fusion energy as a whole, the only current design for a system at some sort of non-labratory scale and there are a lot of good reasons for that.
ITER is not there to be economical, it's there to show the whole thing will even work in the first place. Scale and cost comes later.
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That's great and I want them to succeed but when are stellarators ready to come out of the labratory and be built into an actual reactor of some sort?
ITER is the only system that has the funding and wherewithall to move onto that second step, like it or now
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Well there are designs that do exactly that. They drop a pellet and zap it, something like 10 times a second (depending on yield etc.) That part is easy, the hard part is dealing with the debris on the laser beam windows. Right now the NIF needs at least 8 hours between shots because they have to swap out the disposable debris shields between each shot.
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Wait, why does it take that long to swap debris shields?
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Wait, why does it take that long to swap debris shields?
Read for yourself [ornl.gov] about what those shields do and how they are placed and you'll have your answer.
Duplicate, or something new? (Score:4, Informative)
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Because they did it in a flying car while curing cancer and Alzheimers.
Re:Duplicate, or something new? (Score:4, Insightful)
From your link: "Using the world's most powerful assembly of lasers, a team of researchers say they have, for the first time, extracted more energy from controlled nuclear fusion than was absorbed by the fuel to trigger it." This time, more energy came out than was used to power the experiment. See?
Just in case you don't see, converting electricity to laser light is quite inefficient. They calculated the input energy after conversion in the earlier experiment.
Not that they aren't claiming "ignition", which I presume requires a method of capturing the output energy as electricity.
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It is not accurate to say "more energy than was used to power the experiment." When they say "net energy" they are talking about the total energy in the laser beams, not the energy used to power the lasers. There's a difference. The lasers are terribly inefficient, they waste well over 90% of the energy, so only a fraction of the input energy comes out as laser beam energy. A newer facility will use DPSSLs instead of the flashlamp-pumped lasers at the NIF, but even those aren't spectacularly more efficient.
Sound like a situation from Looney Tunes (Score:2)
Daffy - I know, but I can only do it once.
Laser MagLIF? (Score:2)
My guess is that they used some ideas used in the the MagLIF concept. In the 2000s at Sandia Labs they used to photograph Z-pinch compression with laser backlighting .. it was noticed that whenever they took those photos, the yield of the fusion reaction went up. That's how the MagLIF concept came about. Also in 2012, at OMEGA in Rochester New York, it was shown that you can reduce thermal conduction in Laser ICF with a magnetic field and increase yield. In MagLIF, at Sandia National Labs, a laser is used t
Inertial Confinement (Score:5, Informative)
To put this in perspective, rheres really good reasons the NIF is primarily used for nuclear weapons research.
1 Every hydrogen bomb ever made does exactly the same thing
2. There is virtually no conceivable way to build an inertial confinement power plant
The NIF laser has a fire rate measure in shots per day
Each Firing is like blowing up a hand grenade in an optical assembly.
In order to achieve energy gain the beams have to split and precisely directed over the surface of the target.
Which naturally has to be re calibrated after the last target explodes./
Magnetic confinement isn't great but we will see power plants based on its technology long before ICF
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Each Firing is like blowing up a hand grenade in an optical assembly.
Really liking this analogy...
More energy out (Score:4, Insightful)
"Scientists have struggled to show that fusion can release more energy out than is put in since the 1950s"
Actually, this was clearly shown in 1952 [wikipedia.org]. Maybe you meant "in a sustained and controlled way"?
Sun Lasers? (Score:4, Insightful)
I'm pretty sure there are no lasers on the sun...
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"...bombarding a pellet of hydrogen plasma with the world's largest laser to trigger a nuclear fusion reaction, the same process which takes place in the sun."
I'm pretty sure there are no lasers on the sun...
They misspoke. It should have been Jewish space lasers.
Yawn. In other news, fusion still impractical. (Score:2)
Yes, it's possible positive net energy out of fusion reactors. It's been done a number of times now. It's main effect is to generate clickbait news articles of the "We're saved from the energy crisis" articles.
BUT, fusion reactors are still impractical due to materials limitations (i.e. the walls melt and the neutron bombardment makes them brittle.
Hint: Fusion isn't going to save us from the coming energy crises. Not in a timeframe that matters.
Re:Yawn. In other news, fusion still impractical. (Score:4, Insightful)
Wattage (Score:3)
2.5 megajoules is equivalent to 694 watt hours. For comparison, an electric space heater running on high consumes 1,500 watts, and low is usually around 750 watts. So the output of this experiment was about enough power to run an electric space heater on low for 1 hour.
However, the input was 2.1 megajoules, which is 583 watt hours. So the actual power production was around 110 watt hours, which is the about the amount of power consumed by a MacBook charger plus an LED lightbulb or two over one hour.
The big question is can this be scaled up by a factor of 1,000 to 100,000 to be useful on a power grid.
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Don't forget that one of the initial costs of a pleasant afternoon of driving one's car often involved hiring a horse-drawn wagon full of spare tires and parts to follow along behind the carefree motorists. I wouldn't expect fusion to be any different. Probably worse, in fact, because the principle might be simple, but the tech behind it is a lot more complicated.
perhaps they can deliver it when (Score:2)
Only part of the equation... (Score:3)
Re:Only part of the equation... (Score:4, Interesting)
Also, most of the energy out from a fusion reaction isn't "heat" - it's fast neutrons. Converting that neutron flux to usable energy without creating a bunch of radioactive waste in the process isn't a solved problem either. Also, right now the tritium used as fuel is bred as a byproduct from heavy water used in cooling pools in fission plants. And the amount of 3H we get this way is tiny. A modest commercial fusion plant would blow through the worlds reserves in a matter of weeks.
Breakthroughs everywhere (Score:2)
Interesting, promissing, but ... (Score:3)
It's a great achievement and hopes are rising, however it's still a net gain for the energy delivered to fusion (1.8MJ) to be lower than the released heat (2.5MJ), not the energy to run the lasers (500MJ) and not the electrical energy, which one might get out of the plasma (depending on the conversion, but steam turbines run in 30ish%).
Source: https://www.sciencemediacentre... [sciencemediacentre.org]
BTW, a fun fact is that in a TV adaptation of "The Expanse" they bet on the inertial confinement fusion.
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The reaction was not sustained so, this is bunk (Score:3)
And maybe not the last (Score:2)
Re:Not the first (Score:4, Informative)
Huh? That's just 100% false. Misinformation. Fusion with energy gain has NEVER been achieved in a tokamak. Do you realize the difference between a fusion reaction and energy gain from fusion? Fucking idiot! Energy gain has never been achieved in any controlled fusion reaction. The only time energy has been gained in an artificial fusion reaction is in an nuclear bomb, which is excessive and uncontrolled and therefore impractical for energy production.
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Correct. Grandparent poster is basically an idiot.
Re:Not the first (Score:5, Insightful)
Learn to discuss and refute someone without going all aggro and insulting. It also makes you look bad and hurts any valid arguments you might have.
I know, this is the Internet and Slashdot and all. But why not make a small effort to make the world a slightly better place.
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In most cases I'd agree with you. However, in this case, the OP ( Iamthecheese ) got really snippy about people being wrong. "I'm kind of tired of seeing...Please do a little research". When in fact the OP was the one who was flat out wrong. When you start chastising people for being wrong when it is you yourself who don't know what you are talking about, you lose the benefit of a cordial discussion, IMHO.
Almost as Misleading as the Headline (Score:3)
This is what actually matters for a fusion reactor. To gain net useful amounts of energy you need to generate much,
Re:Almost as Misleading as the Headline (Score:4, Informative)
How could we be at the same spot we were 50 years ago, that is provably false. A lot of progress has been made since then. Maybe the estimates were bad? Off by a factor of 2 or 3? It happens. Fact is that progress is occurring, slow than anticipated, but it's happening. These facilities take a long time to build given their low funding levels.
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I'm not certain that bombs are totally impractical as energy generators. You just need to confine the reaction. This has been done in underground tests. I don't know that the resulting hot cavities have ever been used as energy sources, but they *could* be used that way.
Re:Not the first (Score:4, Informative)
Atomic bombs are very expensive. Much more expensive than the electricity the would produce.
https://en.wikipedia.org/wiki/Project_PACER
It is >100x as expensive as just burning the plutonium from the primary in a conventional fission reactor.
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Huh? That's just 100% false. Misinformation. Fusion with energy gain has NEVER been achieved in a tokamak. Do you realize the difference between a fusion reaction and energy gain from fusion?
They are identical. The law of conservation of energy says that energy out equals energy in plus fusion energy created.
So, if there is a fusion reaction, there is energy gain.
-- most experiments done in tokamaks, however, are done with hydrogen. Fusion is well understood. Once you know the cross sections, you know how fusion works (and we know the cross sections). Plasma dynamics, on the other hand, are hard, but you don't need deuterium or tritium to work on understanding that, and fusion (with productio
What matters is dollar breakeven (Score:2)
What matters is not energy breakeven but dollar breakeven, and we are a long, long, long way from that.
They used a multi-billion dollar reactor to produce 2.5 Mj of energy or 0.7 kwh. That is worth about 8 cents.
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By that logic, are current fission reactors immediately dollar break even? They take a LOT of money to build. (Through loans or whatnot.)
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> By that logic, are current fission reactors immediately dollar break even?
Some are, some aren't.
They mostly were economically viable when they were built, but in the 50 years since we've developed a lot of other energy systems, and made some of those pretty cheap indeed. So cheap, in fact, it's cheaper to build them and turn off the nuke than it is simply to *operate* the nuke.
So that's why nukes are turning off and not being replaced. For now.
Re:What matters is dollar breakeven (Score:5, Insightful)
Forget dollar even, they are not even energy even. The articles like these are often misleading. The net energy gain is only when you count the energy fed to the equipment to the output energy. The energy fed is in the form of electrical energy and output is typically counted in the form of heat energy. So they fed 10 GJ to it and the fusion takes place and it produces 15 GJ, it is considered energy positive. However, you can't convert all these heat back into net positive electrical energy. And we are not even counting the energy needed to operate the plant.
With cheap solar, the fusion is as good as dead. In future, you will see mostly solar, hydro, nuclear and little bit of geothermal and biofuel. Fusion is unlikely to beat any of these in price to be commercially viable. RIP fusion.
Re: What matters is dollar breakeven (Score:2)
Land and transmission is a huge cost factor of solar. Not to mention energy storage costs. Fusion can be a drop in replacement for a power station on the existing grid. Fusion is going to be 60% to 80% of electricity production.
Re: What matters is dollar breakeven (Score:4, Insightful)
We don't know what the parameters of a working controlled fusion reactor would be. It might well be *much* more expensive that solar+wind+storage. It also might be cheaper. I wouldn't bet on cheaper, though. And solar+wind+storage doesn't get you away from the grid. Dense population centers use a lot more energy that they receive as insolation+wind. The Sahara, the Mojave, the Arabian pennisula, etc. will be important suppliers of energy. Perhaps they'll convert it into a chemical form for shipment and storage. Perhaps they'll just feed it into the grid. (Probably some of each.)
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We may have our definitions mixed up. When it says "produces 15 GJ", I understand that the fusion produces 15 GJ. The input is not counted in the 15 GJ.
Also, we are getting to a point where it becomes interesting. The 10 GJ energy input will end up as waste heat, and we get a total of 25 GJ heat. 40% efficiency is possible in a steam turbine => 10 GJ output. In theory, the power plant could run on its own energy.
In practice, there will be some more losses that cannot be recovered, so we are probably not
Re: What matters is dollar breakeven (Score:4, Insightful)
Re: What matters is dollar breakeven (Score:4, Insightful)
That's a whole lot of words to convey the fact you don't understand the difference between temperature and power.
=Smidge=
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But it isn't and it isn't.
Re: What matters is dollar breakeven (Score:4, Insightful)
False, it is directly applicable as many others have said, a conventional turbine will be used to actually convert the heat to electricity.
In your previous post, you said
hot side source... 1,000,000k and your exhaust is 300k you have 99.97% thermodynamic efficiency.
If you think a "conventional turbine" can run with million degree plasma as the hot end, and you can get "99.97% thermodynamic efficiency", you are living in a fantasy world.
You can't, and you can't.
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> Um, why don't you have a term for the amount of power (electricity produced)?
Because it's impossible to calculate power produced from just temperature. That's exactly the mistake you made before.
What you CAN do, however, is compute the maximum Carnot efficiency - the theoretical maximum efficiency that can be achieved by a machine that converts the flow of energy along a temperature gradient to useful work. That calculation requires only knowing the temperatures on either side of the machine. Of course
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I don't bring up temperate to indicate an amount of power. I bring it up because it restricts the materials we can use and how the heat transfer will work. You just ASSumed that I made that mistake when I didn't. Reread what I wrote. At no point did I indicate that the temperate had anything to do with the amount of power being calculated. You just imagined that because you really really want me to be wrong (but I am not).
They are planning to extract heat from the metal walls on the other side of the m
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> I don't bring up temperate to indicate an amount of power.
Remember when you said this?
"Um, why don't you have a term for the amount of power (electricity produced)?"
> I bring it up because it restricts the materials we can use and how the heat transfer will work.
Which is irrelevant because at no point do you demonstrate even basic understanding of how power would be extracted from such a reactor. Even though you clearly read the link provided, you insist that not making physical contact with a hot t
Re: What matters is dollar breakeven (Score:4, Interesting)
The reactor wasn't designed to generate energy, it was designed to investigate fusion. I think the entire approach is totally unreasonable as an approach to energy generation, but it's reasonable as an approach to investigating fusion. (Not really great, as we can't make targets that are sufficiently similar, but I think they're relatively easy to observe.)
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> My understanding is you can take any modern test reactor and scale it to the right size and it'll do the greater than unity fusion.
No no no, a million times no.
This is precisely what they thought, repeatedly, during the early history in the 50s and 60s. It was wrong 100% of the time. Here, read the sad story of ZETA for one example:
https://en.wikipedia.org/wiki/ZETA_(fusion_reactor)
At the time, everyone thought all you needed to do was scale up and it would work. We've thought the same repeatedly since
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You don't know (though you're probably right).
What you can know is that we already know enough to handle the problem with solar + wind + storage. It would take a lot of building, but we could do it. We don't know whether fusion is even possible, and if it's possible, we don't know how easy it would be to satisfy our needs. It *MIGHT* be easier. (I don't think that's the way to bet, but it's possible.)
OTOH, there are uses that controlled fusion could have that cannot be satisfied by anything else except
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They used a multi-billion dollar reactor to produce 2.5 Mj of energy or 0.7 kwh. That is worth about 8 cents.
if you take climate change cost in account fossil energy is probably a lot more expensive. So even at 8 cents, it would be a very good price. Fission is cheaper and is real but humanity choose to not use it for some caveman reason.
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So even at 8 cents, it would be a very good price.
8 cents isn't the price. $3.5 billion is the price.
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$3.5B is very cheap, climate change is a lot more expensive. Also a qanon billionaire paid, by mistake, a chat app for $45B earlier this year. $3.5B is peanuts.
$3.5B for 0.7kwh, so about $55T gets you to the energy budget for a single average US household for one year. Peanuts, indeed.
Yes, that's a bit of hyperbole on my part, since this would obviously not be a linear scale, but your fanaticism is even more absurd.
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$3.5B is very cheap, climate change is a lot more expensive.
That is an idiotic comparison since NIF is in no way addressing climate change.
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Ya, they should just cut to the chase and start producing a sizable amount of energy. You seem to know what you are talking about, maybe you could tell them. Uh...you might want to tell them about your physics PhD first, you know, so they'll listen to you.
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I see they have made fusion at tomakak, but I don't see this as a net positive amount of energy created.
Who cares. It's all BULLSHIT anyway. (Score:5, Informative)
Laser Q are bullshit values they basically just make up as they go along.
https://en.wikipedia.org/wiki/... [wikipedia.org]
Using the traditional definition of Q, Pfus / Pheat, ICF devices have extremely low Q. This is because the laser is extremely inefficient; whereas ETAheat for the heaters used in magnetic systems might be on the order of 70%, lasers are on the order of 1%.
For this reason, Lawrence Livermore National Laboratory (LLNL), the leader in ICF research, has proposed another modification of Q that defines Pheat as the energy delivered by the driver to the capsule, as opposed to the energy put into the driver by an external power source.
That is, they propose removing the laser's inefficiency from the consideration of gain. This definition produces much higher Q values, and changes the definition of breakeven to be Pfus / Plaser = 1.
On occasion, they referred to this definition as "scientific breakeven".[17][18]
This term was not universally used; other groups adopted the redefinition of Q but continued to refer to Pfus = Plaser simply as breakeven.[19]
On 7 October 2013, LLNL announced that it had achieved scientific breakeven in the National Ignition Facility (NIF) on 29 September.[20][21][22]
In this experiment, Pfus was approximately 14 kJ, while the laser output was 1.8 MJ.
By their previous definition, this would be a Q of 0.0077. For this press release, they re-defined Q once again, this time equating Pheat to be only the amount energy delivered to "the hottest portion of the fuel", calculating that only 10 kJ of the original laser energy reached the part of the fuel that was undergoing fusion reactions.
This release has been heavily criticized in the field.[23][24]
On 17 August 2021, the NIF announced that in early August 2021, an experiment had achieved a Q value of 0.7, producing 1.35 MJ of energy from a fuel capsule by focusing 1.9 MJ of laser energy on the capsule.
The result was an eight-fold increase over any prior energy output.[25]
Basically, if at fusion you don't succeed, redefine result again.
Or input. Say you "REALLY only used a small part of energy you actually used".
After all, you can't REALLY use up energy. It just gets converted. It surrounds us. Binds us. Luminous beings are we. Not these... crude numbers. On energy bills and research budgets.
Who can put a value to a child's smile when it hears about all those megajoules? I rest my case.
Oh and, yes, "people with knowledge of the results" ARE talking about equating "energy in lasers" with energy achieved by fusion. Even in their VERY carefully worded anonymous press leak.
Someone sure is hedging their bets about that whole nuclear physics thing by practicing to be a lawyer. Or a politician.
From the "quoted" FT article:
The fusion reaction at the US government facility produced about 2.5 megajoules of energy, which was about 120 per cent of the 2.1 megajoules of energy in the lasers, the people with knowledge of the results said, adding that the data was still being analysed.
From TFS, quoting the Independent:
Researchers were able to produce 2.5 megajoules of energy, 120 per cent of the 2.1 megajoules used to power the experiment.
See? They're not lying or hiding anything. They are being open and transparent about only counting the energy coming out of the laser. Its tip. Of the laser. Beam. Of the laser. This is not a penis metaphor.
It's not THEIR fault those fuckers at the Independent are illiterate monkeys who never studied physics and yet they report on it like they know what the numbers mean.
What input energy? That's not their department. They're scientists. Electricity bill is the purview of administrators. Possibly of cats.
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You are right they fuck with the definition at times, but the fact is that progress is being made. If they were hitting a brick wall on energy output, we can justify pulling the plug. But as it is, meaningful progress is being made.
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Sorry about the reporting, but incremental changes are the way things happen. When you add up a bunch of incremental changes, you find you're in a very different circumstance. AI has already changed things a lot, and most of it's less intelligent than a cockroach.
If you want a bit of perspective, look a how slowly the web took off. (And it was lightning fast compared to most advances.) Or trace the evolution of cell-phones. (Don't count the last few years, as they can't yet be evaluated in light of his
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> This has been done several times in the US
It has not.
The record prior to this point was Q ~= 0.67 at JET in the 1990s. That number was matched at NIF last year.
This is the first > 1 result in history. And it's a long history, the first attempt was in 1938.
I should temper this with the very important point that Q = 1 means something very different in NIF than it does in JET. NIF measures Q by considering the energy of the final bit of laser that makes it into the chamber. There are significant losses
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When was the energy from Tokamaks, or any other artificial experiments except the mentioned NIF (and bombs) greater than needed to trigger/sustain the fusion reaction?
The provided link doesn't mention anything.
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This has been done several times in the US, notably by the tomakak [pppl.gov] at Princeton
Sore about no longer being able to keep using the "Fusion is five years off.." joke every time the subject comes up?
Re:Not the first (Score:5, Insightful)
> Fusion has a reputation of being utopic.
It is not. Fusion is pretty well understood physically, but it is very challenging from an engineering perspective. It would take about 100 billion US$ to develop a fusion reactor. That estimate has been reasonably constant since the 1970s, and actual funding has always been orders of magnitude lower.
Basically, it is utopic as long as we do not actually try.
Re: Not the first (Score:2)
Funding has finally caught up with costs. Commonwealth Fusion Systems has the funding to build SPARC, and assuming it demonstrates whatâ(TM)s expected of it, they have the funding for ARC too, which would be the first (probably) actual working fusion reactor connected to the grid.
Re:Not the first (Score:5, Informative)
It would take about 100 billion US$ to develop a fusion reactor.
The Pentagon received $58 billion more in its budget [yahoo.com] than it asked for. There's half the amount needed in one fell swoop.
They also received an extra $25 billion [commondreams.org] in 21-22 FY. Now you're up to 3/4 of the amount needed.
It seems money is not the issue it appears to be.
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Re:Not the first (Score:4, Funny)
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That's what always drives me nuts, I've been listening to people make jokes about how it's always 50 years away my entire life, but you know what we've never tried to do? Fund the research. /sigh
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...you know what we've never tried to do? Fund the research. /sigh
well, there was the big peak of billion-dollar-a-year budgets from '75 to '90 or so, but today there's a budget of about $400 million a year.
That's just the US government funding, of course. There are also private programs, and also the Europeans, the Japanese, the Russian, and the Chinese programs.
http://large.stanford.edu/cour... [stanford.edu]
Re:Not the first (Score:4)
> It would take about 100 billion US$ to develop a fusion reactor
This gets tossed around all the time, but it's based on nothing.
The estimate was produced in 1972 by ERDA, who was running the US research program at the time. It was based on the recent (1969) success of the tokamak in the USSR, which had for the first time demonstrated that you could indeed keep plasma in a magnet long enough for fusion.
To take that to a commercial system, you had to:
1) demonstrate you could hold it long enough *and heat it*, which the USSR machine did not do
2) scale that up to demonstrate break-even
3) scale that up to demonstrate ignition and net electrical output
If you look at the estimate you're referring to, you will find a graph with three peaks on it. Those three peaks are the construction phases of the three stages above.
Unfortunately, things did not work out that way. (1) worked, in a machine known as PLT. (2) failed. We've built dozens of machines to attempt (2), and not one has worked. It took decades of additional experiments and theory and computers to figure out why.
So dumping $100 billion into it in the 1970s would have done nothing. They simply did not have the theory or computing power. You would better off giving hat $100 billion to Intel, that would have accelerated the development faster than $100 billion of machines.
But hey, who wants facts to get in the way of a good story?
Re:Not the first (Score:4, Interesting)
It is not. Fusion is pretty well understood physically, but it is very challenging from an engineering perspective. It would take about 100 billion US$ to develop a fusion reactor.
To me, the most significant part of this announcement is that it comes from the inertial confinement side, rather than from the magnetic confinement side of the development effort. The route to practical implementation may be a lot shorter from inertial confinement.
And yes, the US would probably spend $100 billion to bring fusion ro engineered reality. Instead, let's let Elon Musk do it for $10 billion.
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What the fuck are you even saying man?
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Seriously? I mean, this is a big step. A lot of people were saying net energy gain is impossible. You are saying it is impossible, even though progress is being made?
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Seriously? I mean, this is a big step. A lot of people were saying net energy gain is impossible. You are saying it is impossible, even though progress is being made?
There is a post above that claims that LLNL has redefined the value of their energy in (as the output power of the laser, rather than the energy required to produce that output power). I am not sufficiently versed in the topic to know if that is the case or not, but if true, this isn't really net energy gain.
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Should we abandon f
Re:Still not viable after all these years (Score:5, Informative)
Fusion people don't really want to have their little baby sun become uncontained
There is absolutely no frick'n way that a fusion reactor can become "uncontained".
Keeping a fusion reactor going is like keeping a match lit in a category-five hurricane. All possible failure scenarios result in the flame going out.
Match in Cat 5 Hurricane - A solved problem (Score:5, Interesting)
Keeping a fusion reactor going is like keeping a match lit in a category-five hurricane.
I have some of those matches. They've been around for decades. You can find them at most sporting goods stores that have a decent camping section. They go by various names, "storm proof", "waterproof / windproof", "survival". They are basically little flares on sticks. When lit a spherical ball of flames shoots out and submersion in water won't stop it. It going to burn for however many seconds it was designed too. Its a violent chemical exothermic reaction once it starts and only ends when it runs out of its internal fuel.
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The nature of a fusion reaction is that it has to be held together by an external force. Fusion relies on atoms being squeezed very close together and heated. If there is no force holding it together, the fusion reaction itself will blow apart and the atoms will be repelled from each other. It is what makes fusion extremely difficult to achieve. Until now, holding the atoms together for a scaled down reaction required more energy that is released from the reaction itself. Also, there isn't a huge amount of
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The nature of a fusion reaction is that it has to be held together by an external force. Fusion relies on atoms being squeezed very close together and heated. If there is no force holding it together, the fusion reaction itself will blow apart and the atoms will be repelled from each other. It is what makes fusion extremely difficult to achieve.
What if, now hear me out, we had such a big pile of fuel that it’s own gravitation would compress it, cause heating, and start fusing. I’d call it a Super Temperature Arrangement Reaction.
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They are basically little flares on sticks.
So not actually matches then. You're not far off base with your comparison. Not understanding the difference between a match and a mini flare is right on par with no understanding the difference between a fusion reactor and a hydrogen bomb.
Loss of Containment is a Serious Problem (Score:2)
There is absolutely no frick'n way that a fusion reactor can become "uncontained".
That's not at all true and in fact, it is the exact reason why we don't have a fusion reactor. In magnetic confinement reactors the fusing plasma becomes unable and loses containment all the time. This causes it to contact the walls of the vessel and either cool or drag in nuclei of heavier elements (than hydrogen) which then radiate loads of energy in the magnetic fields cooling the plasma and topping the fusion reaction.
Loss of containment is the problem everyone is trying to fix!
Re:Not NIF again... (Score:4, Interesting)
Ever heard of a piston engine? Automobiles and home power generators have been powered by "blowing something up again and again" and work fine to produce energy for thousands of hours between servicing (unless it's a Ford). You are right though, it's a huge but not insurmountable engineering challenge to make it work for fusion (the requirement may be 10 ignitions per second with frequent clearing of deposited target debris from the laser beam entrance windows between shots.)
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Ever heard of a piston engine?
Yea, but an engine isn't creating a small star.
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Yea, but an engine isn't creating a small star.
Neither is a fusion reactor.
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The most important thing is that the computer models (LASNEX, HYDRA etc.) work with a high degree of precision. It means that the scaling works as computed. That, in turn, provides confidence that they can build a bigger machine (called LIFE) that will generate "wall power net energy" (more energy than it takes to run the facility).
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I'd agree with you if it wasn't for the fact that the primary hyperbole comes from news and even scientific journalists who hail this as the end of energy problems worldwide.
It's a small proof of concept, in a tiny scale, of things we know already happen on far, far, far huger scales but which we can't adequately control.
It's almost a science-fair project, in essence, of principles well-known and tested but "this one is sure to work and be the end of all our problems, forever" is the real problem - that the