Fusion energy breakthrough by Livermore Lab (opens in new tab)

I don't know. Looking closely at the article reveals that the researchers achieved 1.2x energy gain from the lasers, which are about 1% efficient. Given the SOTA for such lasers is closer to 20% efficiency, this means that they achieved about 60% of break-even. But that's energy, no electricity. Even with the best current methods, about 60% efficiency is the best we can hope for in terms of getting actual electricity from this. So in practical terms they achieved 30% of break-even.

Is that good progress? I'd say so, for sure. Is this a breakthrough? I don't know, especially since the article itself says the data is still being analysed and the actual results aren't published yet. 95% of the article is just fluff about the potential and quoting 3rd parties who celebrate a result that hasn't even been officially confirmed yet.

So, no I don't think it's cynicism, I don't think it's contrarianism, and I do think it's VERY healthy to approach sensationalist headlines with a level-headed and down to Earth attitude instead.

Showing a room full of problem solvers an unfinished problem that lacks critical supporting evidence will no doubt elicit a general response in the skeptical-to-cynical range.

I would respectfully argue that is is a health and normal response given the audience, and should be an expected bias on HN.

This is a “show me the evidence don’t tell me about the possibilities” crowd.

I for one and deeply excited if the data proves out, but my bias is “wait and see.” This could be a massive leap towards proof it will work.

No it's not.

My very uninformed opinion (nuclear physicist by training, but not specialized in fusion, lasers, or plasma physics) is that we’re still 20 years (haha) away from fusion energy making its way into the power grid. And that is assuming this result (or other things, like the relative instability of global energy markets lately) causes an increase in funding for the field so that they can solve all the pesky engineering issues related to efficiency, reactor lifespan, reliability, cycling speed, etc.

Hackernews is not infested with reflexive contrarians.

Hackernews has healthy amounts of skepticism and doubt. Extraordinary claims require extraordinary evidence.

The problem is that fusion "breakthroughs" have been hyped by the press for many decades now. After a few such articles gets people excited and then reality crushes the hype, people learn to dismiss every new story as yet another inconsequential thing blown out of proportion.

I'm commenting about the coverage of fusion in general, not about this particular thing. If it is actually a big deal, great!

When I read what USDOE announces, I hope to be less skeptical.

The basis of my skepticism rests on having written a term paper titled ’Nuclear Fusion, Infinite Energy for the Future’ in 1982, and after the semester sharing my ‘it’s only 20 years away’ enthusiasm with my father -a PhD scientist working for the DoD. Hence it’s forty years since I first heard ‘fusion is always 20 years away.’

Of course I don’t know any LLNL scientists but don’t question their or your sincerity or motivation.

The difference between those and the incentives of financially oriented news reporting, doesn’t make me less skeptical. Their mandate is to present potentially market moving ideas before the market can move.

And because I lived through Pons-Fleischman. Which is to say I have forty years of experience with reports…I mean I see excitement for Tokamaks and I wrote about them in 1982.

No one has any idea how that would ever be viable; other fusion alternatives at least have a way to accomplish thermal transfer from the reactor. Then you somehow have to figure out how to build a financially viable power plant. Oh, by the way, the lasers need to fire 1000x more for that. No one has any idea how that would work either.

There is a reason no one but a national lab interested in fusion reactions with massive financial resources has done this before; its interesting but doesn't produce any kind of viable power source.

Edit: The INF was proposed and designed as means to ensure the viabilty of the nuclear stockpile. It and the French equivalent were never understood as somehow prototyping a fusion power plant for the reasons laid out above. The press reporting here is just not accurate.

I'm excited for both for reference.

1. Energy output != power generation. At the end of every fusion reactor is boiling water to turn a turbine to generate electricity. There's a limit on efficiency and we still aren't there yet;

2. Much like all of nuclear power (fission included) we brush over capital costs and focus on operating costs because that tells a much better story.

3. We still have energy loss from neutron loss;

4. We still have container damage to content with due to neutron embrittlement.

Even the article claims (and this is optimistic) that commercial fusion power generation is "decades away".

Much like FTL travel, we get suckered into unwarranted optimism because we want it to be tru, particularly with the fuel abundance and (no) waste issues. We also fall into th enaive trap of thinking if stars can do it, it must work. But what contains stellar nuclear fusion is gravity.

I'd argue there's still way too much optimism. Pointing out these issues doesn't make you a contrarian. It makes you a realist.

I think that's true. But I also think there is a lot in the way of breathless PR around science topics both from university press offices and lower-end science news outlets. Especially around fusion, which has been 20 years away for a lifetime. So I get why people are going to be particularly skeptical.

I can't imagine what it is like to be in their heads. Even for things I am skeptical about, I still want them to be true if they are truly transformative. My worst case scenario is being cautious, but never, ever, negative.

(1) We are used to the same "news" story being cycled again and again. I think a year ago we heard about a previous breakthrough in ignition. When I hear a story like this my first instinct is that the old story has been recycled and I'm not sure that there is any actual news.

A few months back it was announced that scientists had discovered a black hole that was nearest to the earth and it still gets posted to HN which makes me wonder if they discovered a closer one.

(2) For a while there have been two parallel tracks, one of very slow development efforts at LLNL and IETF which might yield a power source in 50 years and another about firms from Lockheed Martin to scrappy startups who are promising to build a "Mr Fusion" tomorrow. There are still memories of the Pons & Fleischman affair from the 1980s and a strange subculture of LENR activists who claim they will sell you a fusion power source today. One could easily assume "fusion is the new blockchain" in this climate

(3) Fusion research has proceeded with no direct line to a practical power source for a long time, the sharpest critique you hear is "the point of the NIF is to do subthreshold tests of nuclear weapons, not develop a power source"

(4) Fusion is really hard. They might have to get the energy output up 100 times and increase the shot rate 500,000 times to build a real power source, even if 1-3 aren't enough to make you dismiss the whole thing. People will point out that ignition is a big threshold and it might not be so hard to increase the energy output from here out, but we have a long ways to go.

What could be done about that aside from expecting people to just... be better? I think the shape of these forums induces those kinds of comments, even if the community and moderators make a real effort to uphold higher standards. And I think if I encountered the same people in a different kind of forum then I might have a higher quality conversation. Heck, my own comments would probably be a lot more constructive!

Real world example of what I'm thinking: I have a neighbor over one fence who has very different political views to mine. We have perfectly civil conversations in which we're both actually really engaged and trying to understand each others' perspectives and experiences, and not just keeping the peace by avoiding difficult topics. It feels like effort we put into the conversation is rewarded.

I can't shake the idea that there might be "one weird trick" (okay, maybe a handful used together) that could make it more rewarding to put more effort into online conversations on forums like Hacker News or Reddit. One I've wanted to try for a while is to recreate something along the lines of Slashdot's moderation system, but with room for a meta-conversation to take place in "moderation space" (in which all community members could participate) and for there to be opportunities for people to refine their comments in response to feedback — and for doing so to be the norm.

Maybe it's not that simple. That's okay, too. But I've seen different moderation strategies around the web produce very different results, so it seems to me that there should be plenty of room for experimentation, and a lot to learn from doing so.

Overall, I'm glad there are still points of excitement and we haven't come to a halt.

I think the best way to increase the quality of discussion for research results is to avoid posting misleading and hype driven coverage, so the discussion can then focus on the actual research results and their implications, rather than on the poor coverage.

When it was all on the upside, inflating the bubble, there was a fair amount of hero worship here for Zuck and others. People were talking about self driving cars being leased by the minute and changing the world, all with a straight face. Google paid an engineer over $110million because he was going to lead the effort to build a fully autonomous self driving car... As an industry, we've sort of failed on that one. AI/ML was going to lead to mass layoffs of people as we "automated" everything, there were companies just pouring money in to anything related to it to avoid being left behind. I think I heard at a conference over the summer that 90+% of all ML/AI project fail to make it to production; that's brutal, like half I could see but 9 of 10?!? Even if you're getting paid tons of money to do that stuff, wouldn't you want to actually achieve some success? Social media has sort of failed us too, the real media got involved and sort of took it away and then the Russians and Chinese have been using it to tamper with our elections and our ability to practice democracy. The internet is "decentralized" but just try to do that without Google or Facebook or Amazon or other... Since everyone seems to be convinced a recession is going to happen, it's going to take one to sort of get things righted and start the next bubble cycle. Or maybe how the gig-economy was going to change it all. Or everyone was going to learn to cook gourmet meals from blue apron and all the carbon used to move boxes of ingredients around was never going to be a big deal...

It's always based in hype. Every handful of years the geeks and nerds think they're going to take over the world again, maybe we'll do it next time.

In the mean time, any and every break through with fusion is awesome. I'm a geek/nerd so don't believe my hype, but when we crack the fusion nut, we will change the world.

The initial flood of comments is always like that, because they are low-effort dismissals. The first 5 comments on every story could probably be auto-flagged.

The better stuff usually rises to the top eventually.

The first one I see is along the lines of "This was only net energy gain in the plasma and not overall so it shouldn't be called a breakthrough". The net energy gain in the plasma is still a huge step and rightfully called a breakthrough.

The second one is along the lines of "These are just intial results and the article says the data is still under review". This one I totally get. Replication of scientific results and accounting for all sources of errors is real big deal. The NIF had an experiment last year where they we able to achieve an ignition reaction but were unable to replicate it.

Don't get me wrong I respect all the effort it takes to do something truly new, inventing technologies that previously didn't exist with the height of what we can produce today, and every step forward is a triumph. But is tomorrow's announcement going to lead to a step-change in anyone's life before my infant daughter goes to college? I doubt it, and I have work to do. I'm happy to be proven wrong though!

Just because they're excited doesn't mean it's a big deal, nor any guarantee that it works or ends up being practical.

I've heard 'exciting' news about fusion many, many times over my entire life and essentially all of them have come to nought. Or after the excitement settles down over said development we still find that fusion ends up being that magic number of 40 years into the future.

I've even worked in the nuclear game but I don't expect to see my home powered by fusion energy in my lifetime, unfortunately.

People laugh at Russian TV, but to a lesser extent all western governments do the same kind of thing.

The LLNL has one job: research nuclear physics for maintaining the bomb stockpile without actually blowing any up in life fire tests.

Anything else they say is just there to make the public feel good about the billions being spent on weapons research.

There is zero — repeat — ZERO chance that the fusion approach used by LLNL will ever be used in any sort of energy production.

That’s not what their setup is for.

I think scientists are humans after all and they (much like people who rejected bitcoin when it was at $3 and now have to justify their pre-held beliefs) have to justify why they didnt think it was possible or "real" even in the face of multiple fusion breakthroughs.

That device in the photo is great. Looks to be about 16AWG magnet wire. Guessing a 10mm ID of the coil, and about 25mm in length. To get to 26 Tesla, looks like you'd need to push about 33,000 A through that coil. Coil inductance might be about 1uH, and if the test lasts ~1us, then you'd need 33kV to push that 33kA through the coil. 30kV/inch insulation resistance, might not get arcing between the wires in air. Probably running the thing in vacuum? Looks like things check out.

https://www.eeweb.com/tools/magnetic-field-calculator/

>NIF has uncovered some new science

What is the new science? Seems like they are working on making the fuel pellets closer to perfect, which makes sense if you are trying to use the implosion shock wave inside the fuel to be the source of heat and pressure needed for further fusion. I'm imagining that the laser initiates the surface fusion, and then you want that fusion to propagate inward, and need thing perfect, so the fuel doesn't go squirting out the sides (so to speak) stopping the chain reaction.

To be fair, that's not entirely the fault of HN. It's hard to get excited about fusion research when I almost always feel mislead, because it is almost never explicitly stated that we are talking about Q-plasma here. I don't expect much from science journalism, but I feel that the fusion scientists have no problem silently playing along this misconception, which they are perfectly aware of.

We see these comments on every science thread because almost all of these people lack the requisite expertise to weigh in on the actual details, so instead they make a high-level criticism to give the appearance of having some kind of knowledge on the subject. Moreover, they think that crapping on things equates to being a critical thinker, and have convinced one another that this is so.

In order to make inertial confinement work, this process needs to occur multiple times per second

All the fancy stuff with the hohlraum, magnetic compression, target cryo cooling must be accomplished accurately and repeatedly, BUT ALSO shot out of an "injector" to fall precisely into alignment with the lasers, in vacuum within a plasma field...

When you write it all out! Yikes!

Then! This has not included any capture of energy, so that part must be implemented as well, which would effectively mean placing all of NIF target chamber inside a thermal heat exchanger.

So, no, inertial confinement is probably the furthest from ever being a suitable arrangement from a power production standpoint.

Physicists have an uncanny ability to ignore engineering.

As a proponent of fusion and fusion research, it's important to keep the focus on what is valuable about the work being done and not mislead the general public about flights of fancy.

If you want to understand radiative pressure and plasma characteristics, this is the place to be, for sure

JET Tokamak was within a factor of 2 and ITER will overshoot by a factor of 10.

1. It is, purely, bomb research dressed up as civilian activity for funding purposes. Everyone working on it has top-secret clearance.

2. It has no consequence for any civilian project. The target that produced a couple of MJ cost $10M. (2.4 MJ is <0.7 kWh.) A real plant would need to feed them in at a high rate. Q is not the important measure. Dollars out / dollars in is the right measure, and everyone is still at exactly zero, with no plausible prospect of ever exceeding 1.

3. Extracting useful energy would require capturing hot neutrons in a "blanket", heating it up, and running fluid through it to boil water to drive a steam turbine. The minimum practical size for such a "blanket" exceeds that of a large fission plant. To collect enough neutrons to be useful requires a huge volume of plasma, as even compressed plasma is very diffuse vs. fissiles.

4. Compressing the plasma with superconducting magnets could increase density, but then the neutron flux through the smaller surface area of the chamber wall would destroy it that much more quickly.

5. The hot neutron flux would also quickly weaken the structural parts required to contain the enormous forces exerted by the electromagnetic coils. Superconducting coils would impose even larger stresses. No research has gone into identifying a viable material, in decades, despite that none is known. After a short time the reactor parts would all become weak and (also) fiercely radioactive. Repairs would need robots not yet designed.

6. Civil fusion would require a large amount of tritium, which no one knows how to make economically.

7. Steam turbines cost a lot to operate, regardless of heat source. No other generation method relying on such steam turbines -- coal, fission, geo -- is today competitive vs. renewables. As the cost of renewables continues on down, they get less competitive by the day.

Fusion is intrinsically interesting, just not for power generation.

One company, Helion, is trying to make a fusion device that does not emit many hot neutrons. However, achieving conditions for this process, D-3He, is even harder than for D-T fusion. They hope to breed their own tritium, which would eventually decay to the 3He they actually need, but it is not clear how they will produce enough. (Fun fact, 3He loves to turn back into tritium.)

If they cannot, but they do get it working, it might end up usable for outer solar system exploration, which is difficult to power.

This "milestone" provides exactly zero meaningful information for the magnetic confinement fusion that is the only avenue being pursued for civil power.

Fusion offers no prospect of "unlimited free energy". It offers instead very expensive energy, or possibly none at all. We already have access to unlimited free energy, and need only build out the solar, wind, and maybe tidal systems to collect some as it goes by.

https://www.world-nuclear-news.org/Articles/First-Light-team...

Fusion has the strong advantage (and disadvantage) that it is a powerful neutron source. Even a very low performance reactor can be useful as a neutron source

https://ats-fns.fi/images/files/2019/syp2019/presentations/T...

Fusion might be useful for making isotopes long before it is competitive as an energy source. In the 1980s I know scientists were looking to hybrid systems that convert ²³²Th to ²³³U and ²³⁸U to ²³⁹Pu as fusion reactors produce so many high energy neutrons that they could be better than fast breeders for manufacturing fuel for thermal fission reactors. In fact, it is very possible a fusion reactor could be used to make fuel for nuclear weapons.

Before this is not solved:

"it's not actually generating power"

I simply would not talk about a real power plant yet, because a real power plant has economic constraints. As long as the current approach is not even generating energy, all the scepticism is warranted, if we are talking about something that is supposed to solve energy generation and climate change. This is why people are upset with it - we need not promises of unsolved tech, but solutions now. So fusion remains exciting and cool tech and I love to read about its recent progress, but please without illusions. Even if they could generate power tommorow - it would still be a very long, unknown way, till it actually helps us.

The article is old news before it was written. The article mentions the previous 'success' (yield was higher than previous experiments), and that was over a year ago now. They haven't been able to reproduce the previous experiment even knowing as precisely as they can what they perceive to be the preconditions necessary for an effective reaction. It also seems that this article was written about a single experiment. They will not be able to intentionally repeat the experiment. The manner in which they're exploring the pareto front is like groping in the dark to find a light switch that has an unknown texture and conformation. It's a classic monte-carlo simulation but they have one iteration every several weeks or months, and they cannot even possibly identify all the controlling parameters, nor do they have the necessary throughput or bandwidth to succeed in their pursuit without windfall.

The low hanging fruit providing the basic harmonics of the solution were discovered well before I was even introduced to this technology (in the 70's and 80's. Coincidentally around the moment of the genesis of many of our modern treaties on weapons testing).

You are overly optimistic, a 40-60% increase in nearly nothing is still nearly nothing. The PR campaign around this event is I think more significant in its political convenience, and in white washing the purpose of the facility. There are significant discoveries that still need to be made to even make the reactions consistent, and they will not come conveniently or quickly. Once the reactions are better understood and the mechanisms can be manipulated with intent the distance between the science and a practical industry / commercial product will require even more hurdles that stretch the imagination to be overcome. For instance I cannot conceive of a practical mechanism for actually utilizing any fraction of the massive amount of energy released in a fraction of a second in a chaotic murder of wavelengths and particles. The most practical way we've yet discovered for converting neutrons to electricity is through boiling water. Grossly inefficient in other contexts, I'm not sure that has even marginal utility in this scope.

I for one am 100% sure I barely know what I'm talking about. My disclaimer is that I'm not a physics guy, and high energy density physics was only a hobby of mine at one brief point in my life. Through perspicacity and access to papers and people, this is my honest mental model of the whole thing. You're welcome to your perspective, but although you seem well informed you sound very inexperienced.

https://coldfusionnow.org/power-equivalent-to-the-sun-we-alr...

This is one aspect of the problem. THe another aspect is that we should create decentralized technology that everybody can use at home. It would make our world a much better place, much more resistant to many things (including terrorism). I think the small amount of virtually infinite energy is a much better option.

https://ndb.technology/

    > Very disappointed by the discourse in this HN thread. The same old quips over and over. "NIF is just a nuclear stewardship program", "it's not actually generating power", "fusion still 30 years away".

Basically, I came to the comments to hear from the skeptics. Of course, most of the skeptics fall victim to a mental trap.

I think there is one key difference between "what I was looking to read from skeptics" and "what most skeptics used as arguments". The information I was seeking: to understand the difference between what the "breakthrough" was being reported as and what the breakthrough actually was. The information I received was: "this is impossible for (reasons)"

An equally important thing I was seeking was to understand was how this work might affect other industries (before it results in "fusion power").

The thing I'm least interested in is hearing "why it will never happen." I think most of us know many of the reasons this is a "Marsshot" problem[1]. I think most of us get annoyed when the media presents news in a manner that provides the general public with extremely unrealistic expectations and are sensitive to the dangers of that, but we get frustrated by those kinds of comments because, likely, none of us need to be told that! :)

It's impossible to make a useful argument to a skeptic that "this technology will exist in (insert timeframe)." The point at which (timeframe) is a trustworthy estimate usually coincides with the technology maturing to the point that the skeptics fall off (or turn out to be right if "timeframe" is never). And there's a long way to go (I think I saw a list of 10 or so "extremely hard problems") but this certainly appears to be something that is chipping away at one of the "impossible problems." Over-simplifying as this is, the rate at which technology advances is not linear; it accelerates. The next problem may not be as difficult or knowledge we attain from solving this one may be able to be used to solve related problems[2].

[0] There were several others on the topic and being ft.com, I assumed it would require a subscription that I do not have.

[1] Maybe far more difficult, but I never liked "moonshot" when describing something that hasn't been done, yet.

[2] Again, not a physicist, but reading through various "fusion is doomed" lists, many of the problems center around "the word 'hot' is a woefully inadequate description".

> So we might be as close as 10-20 years away, as always!

I don't really get the cynicism here. This is a huge milestone that's been passed. Maybe with this, we actually will be 10-20 years away. Or maybe it's more like 30-40, who knows. But this experiment shows that net-positive energy is actually possible to do with our current understanding and technology; before this, I believe much of the skepticism was based on a belief that it may not actually be possible to get more energy out than put in, at least not without technology that's significantly out of reach.

Look, it's really simple:

1. This is a very hard and expensive problem.

2. Progress IS being made.

It's not clever or cute to diminish progress on this problem.

Continual refinement may finally get us where we need to be, but it's going to take a long time.

The viability of fusion has been centered for a long time around getting more power out than you put in and once that marker is met it's viewed as the last giant hurdle in the way. There's still plenty more R&D that needs to be done before it can easily / readily scale though.

It's where nuclear was in the 60s basically. Even if it only ever gets to be comparable to nuclear in terms of costing but with none of the hazardous byproduct, it will come out ahead. When you consider the environmental factors involved in battery production it is pretty clear that fusion at least has the potential to be the cleanest sources of energy. Whether it ultimately gets there is another question.

The other thing is that if LLNL is still using their own definition of Q, it's not necessarily the case that they've demonstrated net-energy breakeven; they like to compare direct energy delivery to energy release, so when calculating Q they basically pretend there aren't any energy losses from actually running the huge laser facility itself. As a result, LLNL assumes that laser technology will improve to the point that real-life Q can catch up with their "scientific Q" metric. (IIRC I think "Project LIFE" was supposed to develop some of those technologies, but it never worked out, possibly since NIF is so far behind their promised schedule.)

1 fusion plant has less NIMBYs to deal with than wind-on-land, for example.

But yes, could be that still it's too expensive by the time it becomes available. By then I hope we can make a fusion plant so small it fits on a space ship and power an Epstein drive :-)

Right now they are, but they often rely on materials from politically unstable regions (particularly Africa), or potential political rivals (China). Also, many solar panels require polysilicon from China, which is almost certainly produced with forced labor.

https://www.csis.org/analysis/dark-spot-solar-energy-industr...

https://foreignpolicy.com/2021/04/12/clean-energy-china-xinj...

https://www.theguardian.com/environment/2022/nov/29/evidence...

And it's not just a China problem.

"On batteries, there were major issues with the mining of between 15% and 30% of the world’s cobalt in the Democratic Republic of the Congo. Amnesty International found that children, some as young as seven, were working in artisanal cobalt mines, often for less than $2 a day. Mining conditions were reportedly hazardous, and workers often did not have adequate protective equipment and were exposed to toxic dust that contributed to hard metal lung disease."

The US is trying to crack down but Europe is lagging behind on it. However, if the report's claim (which I see no reason to doubt) that China has 82% of the global polysilicon market is true, with most of their polysilicon production being in the Xinjiang region, calling solar panels (or batteries) "cheap" is fairly distasteful considering their sources.

Maybe fusion will stay a small part of the energy mix for decades even after the first commercial plants are built but be part of what eventually enables us to use orders of magnitude more energy than we do now…

It could still be a useful technology, especially in space. I could see a moon or mars base powered by fusion.

Cost effectiveness is also a myth perpetrated by the death of nuclear executed through bureaucracy.

The nuclear, however, is currently the true energy source to use, technologically much simpler (than fusion) to execute with decades of experience making it the safest out there. It is the zero-carbon environmentally friendly energy source.

I think it might be fine that fusion power may be more expensive in some ways than fission, as long as its reputation is kept clean (figuratively and literally). Market fusion power as the savior of humanity, and get enough people to believe it, and it'll be fine.

In theory much of that is excessive but there is a long history of very expensive mistakes with massive cleanup efforts. The US talks about three mile island as the largest nuclear accident ignoring the Stationary Low-Power Reactor Number One that killed 3 people. All that complexity and expense comes from trying to avoid real mistakes that actually happened.

I might be in the opposite camp as you but this is very much a "where were you when—" moment for me. I'm sure someone will pop in to disappoint me but I think the point is it's no longer a hypothetical exercise.

Fusion is a much safer alternative both in incidents and fallout

Yeah and with a breeder fission reactor we could reduce this to below 1% probably. With a thorium breeder the fuel cost might be essentially 0%. In the vision of Alvin Weinberg you literally just drop some thorium into the fuel salt every once in a while.

But the real issue for nuclear energy is currently capital cost and time not fuel cost. And capital cost can go down massively with GenIV reactors as well.

So I don't see how fusion will be cheaper.

> In fusion it could be lower

But eventually you have to start breeding tritium, so wouldn't that make it more expensive.

> Disclaimer: I switched from studying fusion energy to advanced fission 16 years ago.

Awesome, we desperately need GenIV reactors (even if I dislike that term).

I'm pretty sure I saw that in a 'goop' sales pitch.

I guess we still don't have anything better than boiling water, right?

“The Lawrence Livermore National Laboratory experiment shows that scientists can get more energy out than put in by the laser itself. This is great progress indeed, but still more is needed: first we need to get much more out that is put in so to account for losses in generating the laser light etc (although the technology for creating efficient lasers has also leapt forward in recent years). Secondly, the Lawrence Livermore National Laboratory could in principle produce this sort of result about once a day – a fusion power plant would need to do it ten times per second. However, the important takeaway point is that the basic science is now clearly well understood, and this should spur further investment. It is encouraging to see that the private sector is starting to wake up to the possibilities, although still long term, of these important emerging technologies.”

While this spins it in an optimistic way, the challenges to make this work are significant. The laser is quite inefficient, so the gain must be much much larger before you have net energy gain. To scale it up to implode a capsule tens of times a second rather than a few times a day, is in the order of 100.000 times more frequent than today.Thus this is a long way from commercial production.

Q-total is still below 1, but some of that can be improved through already-known laser efficiency advancements, and also by pushing Q-plasma higher.

I think pushing Q-plasma above 1 is the big gate though, isn't it? I mean, partly psychologically. Showing that it's actually technically possible.

I'm curious - given that this is the first time we have ever done this (even with the constrained definition as discussed in this article), how there can be a '"usual caveat" about all of the "got more energy out than we put in" stories'?

AFAICT, this is the first such "story" to have ever happened artificially in history.

I'm not by any means well informed on the matter, but isn't the lunar surface covered in tritium deposits?

It might make sense to mine the moon sooner than later. Once we have the necessary equipment and resources there, the delta-v for getting the mined product to Earth isn't nearly as substantial.

Building lunar mining tech is likely to unlock all sorts of advances for the human race.

[1] https://en.wikipedia.org/wiki/Breeding_blanket

But NIF was never, and is not, designed to be a generating reactor, or even a prototype of a testbed. It's a weapons physics facility that happens to do some energy generating research sometimes.

That aside, hitting Q=1 (and be able to use the device again) in any way at all using any equipment is a major milestone that proves humans can get there. From that point, in theory, it's just engineering.

I don't hold out much hope for a practical, economical reactor from inertial confinement, but it's certainly exciting to see them achieve ignition & scientific breakeven, even if it's 10 years behind schedule. The one nice thing about ICF is that the energy gain shoots up dramatically once you cross the ignition threshold. That means they're arguably closer than tokamaks, even though both concepts need ~100x the demonstrated gain to get from where they are now to a workable reactor. (Ie, tokamaks have hit Q~0.3, need to get Q~30, vs ICF that has hit Q~1, needs Q~100).

Small scale fusion on the other hand would have a viable niche application at the poles, in the sea or underground or any other environment that is without sun or space.

Meanwhile the VC money is quietly piling into tokamak and stellarator magnetic confinement designs, driven by high expectations from real breakthroughs in ReBCO tape manufacturing technology. These superconducting tapes can be manufactured like semiconductors and can develop magnetic fields that were previously impossible, which is a key manufacturability enabler in a design whose path to commercialization is far better de-risked overall. There are still concerns with the durability of equipment needed to capture the neutrons in these designs too, but ReBCO tapes were the real prior changer.

This is last unknown in this equation. All others are already known, from achievements of last few years.

Materials research is one of primary targets of ITER.

If good enough materials will not being found fast enough, will need to use clear reactions like boron-carbon fusion, in which need magnitude higher temperature, so practical device will be few times larger (because x-ray losses, proportional to surface square of plasma configuration).

The real question in the experiments here at NIF was about whether inertial confinement fusion would work. This is very promising progress.

Also NIF spends a good portion of its time on weapons research, not fusion power so it's only been a recent focus.

Taking those costs into account, being able to use this method to generate power seems really non-optimal.

Scaling up Qplasma from 1 to ~1000, and scaling up operating time from a microsecond to a megasecond are just two of them.

I have a feeling there is still some science to do.

If we could pick a World 3 track to be on, which one would it be? Now, what can we do to try to push ourselves onto that track? That's what gets me up in the morning.

https://youtu.be/kVOTPAxrrP4

They just won't have a choice; if we can provide a real alternative, we can just forbid gas car altogether. Just like we banned CFC to save the ozone when better alternatives were developed.

The main issue is that our electricity grids and production facilities aren't ready yet to sustain a mass shift to electric, so we need to ease in the transition. But the moment they are, there is no reason to delay any further.

This is the first time that the laser’s photon energy was exceeded by the energy produced by fusion. But this machine isn’t optimized as a power plant, just to demonstrate fusion (mostly to improve modeling of H-bombs, actually). The shots take hours to do, the tiny bombs are currently expensive to make, the chamber for the tiny bombs isn’t designed to capture heat, breed fuel, or even withstand damage from higher yield fusion. Another machine would be needed to demonstrate like 10-100 tiny bombs per second, and the efficiency (and repetition rate) of the lasers would need to be higher and the energy gain also needs to be much higher (but if they got “ignition” where the fusion heat helps sustain the reaction, this may be doable). And need to find a way to make these tiny bombs cheaper.

I need to explain what Q is in the context of fusion. Basically, you heat the plasma with some energy (Energy In), and the fusion reactions produces some energy (Energy out). Q is basically the ratio (Energy out)/(Energy In). When Q is bigger than 1, we call it break-even. However, (Energy In) is not the actual cost of energy you need to run the whole facility, it is only the Energy that reaches the plasma. The same goes for (Energy out): this energy cannot be captured 100% efficiently. Some of it will heat the plasma itself, some of it will escape but the conversion back to electricity is not 100% efficient.

So in a sense, Q > 1, aka break-even, does not mean commercial fusion, it is only a kind of a psychological barrier to achieve (so this is what the NIF announced; still a major breakthrough). We need at least to achieve (Total Electrical Energy out)/(Total Electrical Energy In) > 1 to achieve commercial fusion. But physicists consider the rest as engineering problems, not physics problems. And great news, there is no theoretical limit on how big Q can be: for example, the sun has a Q of infinity, as there is no required energy input. Current estimates put Q at least 30-40 to achieve commercial fusion (again: there is no physical limit to achieve that, only engineering difficulties).

Main costs are: difficult to define, because we haven't commercialized a reactor yet. I would say, for now, everything around it is expensive (magnets, the blanket, the fuel (tritium)). However, once we have sufficiently understood the optimal parameters on how to produce net gain energy, there is no reason why the design of the reactor can't then be simplified to be mass-produced.

Note: the technology used by the NIF is very different from what I described for a realistic fusion device: what I described is called magnetic confinement, and what the NIF did is called inertial confinement.

It is possible though that they could also use this for some fundamental research into how fusion works as a process.

These over-unity reports are meaningless, because every damn one of them only measures Q-plasma, not Q-total.

https://en.wikipedia.org/wiki/Inertial_confinement_fusion

Can't you use energy produced from existing solar panels to create more of them?

Each will be converted to heat in walls and in shielding blanket, which cooled by water.

They could easily buy a newer, more efficient laser for example. That would increase the overall efficiency, but would ultimately be a waste of money. It wouldn't change the science at all, and the point is the science.

I don't think they used that for this recent event, so if it works out that's potentially a significant improvement.

- Breakthrough: a sudden, dramatic, and important discovery or development

- Milestone: a significant point in development

This is clearly neither 'sudden' nor 'dramatic' and should NOT be celebrated or acknowledged as a 'breakthrough'. This level of journalistic malpractice is worth noting, and I have contacted the author on Twitter to voice my disapproval.

https://youtu.be/KtqC8W0_Ups

New things are hard. Nothing truly worthwhile is easy.