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US Department of Energy: Fusion Ignition Achieved

energy.gov

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Re: US Department of Energy: Fusion Ignition Achieved

#691

Post by qwytw »

naikrovek wrote: post #681
w0mbat wrote: post #577

Earlier quoted context omitted.

Their total power draw from the grid was 300 megajoules and they got back about 3 megajoules, so don't start celebrating yet. Source: New York Times.

don't you think it's nuts that your arrogance would have you believe that the people on the ground doing the experiment know less about the power consumption and output than you do? Because I do. There's a lot of supporting stuff as well as energy to drive that stuff that goes into leading edge tech development like this, that does not matter in terms of the reaction itself. If they say they achieved more output than…

I'm sorry but you sound much more arrogant here with your strange assumptions. AFAIK all of those things he said are based on the data from the experiment. And I've read the same (i.e. that it's very far from being energy efficient).

> will believe Wouldn't be better if you were able in to verify stuff to some degree yourself instead blindly trusting every expert (not at all implying that the people who did this experiment are untrustworthy but your bound to run into some bad apples with this attitude eventually)

Re: US Department of Energy: Fusion Ignition Achieved

#692

Post by mnl »

SiVal wrote: post #612
eklitzke wrote: post #262

Earlier quoted context omitted.

Tangentially related, but I think this is an interesting fact, all the atoms in our universe/galaxy/solar system with a mass up to that of iron are formed in the core of stars in stellar fusion. Hydrogen fuses into helium, and as a star nears the end of its lifetime you get heavier elements like lithium, carbon, and so on. Under normal stellar fusion no elements heavier than iron will be produced, and iron is only el…

Iron is always spoken of as the dividing line, but I'd like to know whether iron is exactly on the line, on one side (which?), or it depends. IOW, does fusion of iron atoms release energy (hydrogen side of the line), absorb energy (uranium side of the line), neither, or either (depending on conditions)?

Look at the binding energy curve: http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/nucbin.htm...

Re: US Department of Energy: Fusion Ignition Achieved

#693

Post by rtpg »

petilon wrote: post #330
Rebelgecko wrote: post #144

Earlier quoted context omitted.

It was discussed a lot in the threads about this yesterday, but apparently the lab had relatively inefficient lasers. Newer ones are an order of magnitude more efficient

This is what I captured from the press conference: 300 megajoules was used to generate the laser (this is also captured in [1]). They also mentioned that newer lasers have 20% wall plug efficiency. If so, they need to improve the energy output by 5x in order to break even relative to wall plug energy consumption. [1] https://techcrunch.com/2022/12/13/world-record-fusion-experi...

So if we had the 20% wall plug efficiency, then we need that 3.2:2 ratio to become 10:2 to hit break-even. That looks like a huge gap but maybe there are tricks here that resolve this once you get over the initial gap.

Re: US Department of Energy: Fusion Ignition Achieved

#694

Post by lostmsu »

jasonhansel wrote: post #635
lostmsu wrote: post #462

Earlier quoted context omitted.

In principle inertial confinement is not much different from internal combustion engines where piston compresses the mix, and the explosion energy is harvested. Here lasers compress the mix, and the explosion energy is not yet harvested (but measured). Tokamaks (the other approach) are more like jet engines in that they sustain burning. But currently the burning in tokamaks requires more energy than it generates.

Could it be argued that we should invest more in ICF and less in tokamaks, given this result? I don't know enough about the field to say.

I personally believed so since a while ago, for that exact reason. Although I was thinking more of miniaturizing the existing bomb design where fusion material is surrounded by a fission shell made of material with lower critical mass. But I am no expert either.

Re: US Department of Energy: Fusion Ignition Achieved

#695

Post by opportune »

vlovich123 wrote: post #647
opportune wrote: post #636

Earlier quoted context omitted.

I’m not thinking about just replacing grid energy, but carbon removal. If we can get fusion scaled up and efficient it should be no sweat to use it to just remove carbon from the air In fact carbon removal might be a great way to subsidize fusion at the outset so that it can be overprovisioned/have a guaranteed minimum price

$600 per ton of CO2. The industry is trying to get to $100 per ton of CO2. Energy estimated is 1,200 kilowatt-hours per ton of CO2 removed. Nuclear fission energy averages 0.4 cents/kWh. That's $480 in energy costs alone (ignoring profit margins for removal, etc). Why would bleeding edge fusion that requires cutting edge lasers, magnets, and various other containment stuff have a cheaper energy generation cost? I cou…

Those are figures for current electrical production schemes.

After decades of R&D fusion should become significantly cheaper than fission per kWh if only due to having less of a regulatory burden and smoother permitting process.

It’s more expensive now, but in the long run it will be cheaper.

Re: US Department of Energy: Fusion Ignition Achieved

#696

Post by jboy55 »

floxy wrote: post #686
w0mbat wrote: post #577

Earlier quoted context omitted.

Their total power draw from the grid was 300 megajoules and they got back about 3 megajoules, so don't start celebrating yet. Source: New York Times.

I guess we should take this as a lesson in communications. The "breakeven" thing is a red-herring that should have been have been left out of the message, or at least only mentioned as a footnote. The critical ELI5 message that should have been presented is that they used a laser to create some tiny amount of fusion. But we have been able to do that for a while now. The important thing is that they were then able to…

and not a gigantic amount of fusion that you have in thermonuclear weapons,

Ironically, this experiment was designed primarily to simulate the fusion you have in thermonuclear weapons. That's the NIF's purpose and the purpose of this experiment. From Nature https://www.nature.com/articles/d41586-022-04440-7

"Herrmann acknowledges as much, saying that there are many steps on the path to laser fusion energy. “NIF was not designed to be efficient,” he says. “It was designed to be the biggest laser we could possibly build to give us the data we need for the [nuclear] stockpile research programme.”

Re: US Department of Energy: Fusion Ignition Achieved

#697

Post by opportune »

oreilles wrote: post #669
opportune wrote: post #584

Earlier quoted context omitted.

100% agree. We should be dumping as much as we can in getting fusion up and running ASAP. It could be a silver bullet to stop climate change alone, and by driving energy costs lower, enable huge innovations in AI/automation and increasing material wealth. $1T to move fusion forward just 5 years from eg 2040 to 2035 could alone have a huge ROI in terms of climate mitigation and decarbonization

Cheaper and cleaner energy has never in the history of enery lead to global reduction of pollution, actually pretty much the opposite. Plus, nuclear power is already virtually free and has been available since the 1970s. If stopping climate change was an energy source problem, it would have already been solved then.

I’m not anti fission. But the reality is that many are and the NIMBY effect is strong. You don’t necessarily have that with fusion.

Also, there should hopefully be much less pomp and process around fusion compared to fission due to the safety/radiation profile being much safer.

Re: US Department of Energy: Fusion Ignition Achieved

#698

Post by jboy55 »

tgflynn wrote: post #303
jocaal wrote: post #256

Earlier quoted context omitted.

I don't think a pure fusion bomb will have any form of advantage compared to the current hydro-bombs. They wouldn't produce more energy, but will need more gear to reach ignition.

The advantage would be that you wouldn't need tightly controlled and hard to make materials like U-235 or Pu to make one. I'm not in any way saying that using lasers would be a plausible route to such a weapon, since the NIF facility is huge, but if it turns out that the research needs to focus on how to get more output per shot, which I think it inevitably would since a typical conventional or nuclear power plant ge…

One use for such a 'laser initiated fusion' is the LLNL (Teller) proposed X-Ray laser satellite from the Star Wars program in the 80s. The proposed solution then was to use the X-rays from an exploding bomb at the heart of a satellite and amplify and focus them through a 'lasing' material. It turns out they never found a lasing material that would work, and it would be fairly easy to confuse defeat it, so the project died. What also killed it was the end of the testing program.

Re: US Department of Energy: Fusion Ignition Achieved

#699

Post by opportune »

vlovich123 wrote: post #652
opportune wrote: post #580

Earlier quoted context omitted.

I agree. I am thinking of my future children or myself into my old age. Even if we don’t get commercial fusion until the 2040s, imagine nearly limitless energy (of course we still need to pay for likely massive capex, R&D, and transmission) and its repercussions! At the very least we can likely pull carbon out of the air faster than we put it in. No more destructive hydropower, no need for fission plants, radically r…

I think you're hand waving too many of the problems away and letting your imagination run way ahead of reality. > no need for fission plants Not sure why this is a goal in and of itself. Everything you said is available today with fission and yet still too expensive to remove CO2. Fission has a more real shot at getting to the right price point before fusion even gets off the ground so why not push for more arrows be…

Energy is an input to basically every single thing we make or do. In economic models it’s often been found that “technology” parameters (inversely) correlate almost entirely to energy prices.

If energy cost very little, we could do previously unviable things like vertically farm and let farmland go back to nature, smelt ore onsite, or run simulations/models for a fraction of what they cost now.

Re: US Department of Energy: Fusion Ignition Achieved

#700

Post by jboy55 »

dgacmu wrote: post #221
spullara wrote: post #113

Earlier quoted context omitted.

I mean almost all of the power in a nuclear bomb comes from fusion. The fission part of it is just like the detonator for the real explosion.

This is actually backwards. Fusion weapons are substantially higher yield because they result in more fission, partly by preventing the fission primary from blowing itself up before it has finished. Wikipedia: "Fast fission of the tamper and radiation case is the main contribution to the total yield and is the dominant process that produces radioactive fission product fallout." https://en.m.wikipedia.org/wiki/Thermon…

Most of the fission energy in an H-bomb comes from the massive amounts of neutrons created by the fusion bomb initiating a fission reaction in the U-238 tamper of the secondary. The primary is used for its X-Rays, which cause the incredible pressures within the secondary by ablating the surface of the cylinder. When you look at this experiment and see it uses x-rays to ablate case containing the hydrogen, causing an implosion, the purpose of the experiment is clear.
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