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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

#251

Post by tetha »

Robotbeat wrote: post #142
simiones wrote: post #112

Earlier quoted context omitted.

That's a very apt analogy, as both this and Manhattan are weapons research programs. I'm not very excited in hearing we'll get even more powerful thermo-nuclear bombs.

That isn’t what this would be used for. In fact, yields for the largest deployed H-bombs today I think are smaller than they once were (due to better targeting capabilities).

This is true. The issue is that already a relatively small nuclear weapon is perfectly sufficient to wipe out most to all civilian structures. However, it does so in a roughly circular area, and you need to increase the initial explosion a royal lot to increase the devastated area by a bit. And as you increase the overall spherical blast of the weapon in order to increase the circle of doom on the ground, more and more explosive power just vaporizes air.

That's why MIRV was introduced. One ICBM delivering 10 - 20 small warheads result in much greater devastation than an equally heavy warhead in one package, because less power is wasted on air and space.

It's morbid math, but it makes sense.

Re: US Department of Energy: Fusion Ignition Achieved

#252

Post by mixmastamyk »

whycome wrote: post #3
mustacheemperor wrote: post #2

I don't know about everyone else, but I'm taking this particular moment just to swell with pride and excitement for this achievement by science and forget about the details of how much more needs to be done to create the first power plant. I'm remembering when I first learned about fusion energy development, how distant and unfeasible it seemed, and regardless of how long the road ahead still is it's incredible how f…

I guess December 5th was Ignition Day and we didn't know it?

Also Repeal Day for those who want to get lit.

Re: US Department of Energy: Fusion Ignition Achieved

#253

Post by worik »

Robotbeat wrote: post #133
sillysaurusx wrote: post #115

Earlier quoted context omitted.

This tweet claims that 500MJ of energy was required: https://twitter.com/latzenpratz/status/1602686252486217728 > "had to put 500 megajoules of energy into the lasers to then send 1.8 megajoules to the target - so even though they got 2.5 megajoules out, that's still far less than the energy they originally needed for the lasers," says Tony Roulstone of the University of Cambridge. But it's good to finally see progre…

That’s only because they’re using old school flash pumped lasers, not the new solid state lasers you’d use today if you wanted to make a power plant demo.

Why are they using these "flash pumped" lasers if more efficient ones are available?

Re: US Department of Energy: Fusion Ignition Achieved

#254

Post by kzrdude »

mFixman wrote: post #104

Widespread energy generation nuclear fission is politically impossible in most Western countries. Why are people optimistic that fusion won't have the same kind of problems, such as new plants being too expensive to build and old obsolete plants being too useful to decommission?

It is already widespread, being used for 10-20% of US energy, isn't it? And 30-40% in several European countries. I think it's definitely possible since it's already in place, we just need to talk about it more.

Re: US Department of Energy: Fusion Ignition Achieved

#255

Post by lizknope »

simiones wrote: post #112
bioemerl wrote: post #20

Here's your most exciting paragraph > LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE). Many advanced science and technology developments are still needed to achieve simple, affordable IFE to power homes and busines…

That's a very apt analogy, as both this and Manhattan are weapons research programs. I'm not very excited in hearing we'll get even more powerful thermo-nuclear bombs.

Soviet Union built this and it wasn't really practical and ended up leading to test ban treaties

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

Re: US Department of Energy: Fusion Ignition Achieved

#256

Post by jocaal »

tgflynn wrote: post #111
jkelleyrtp wrote: post #33

> LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE) Yesterday, everyone was complaining about the 2.2:2.0 ratio, but now we're working with 3.15:2.05. With modern lasers, that'd be a total Q of 0.375 assuming 100% ef…

I wonder if it might be possible to gain not percentages but orders of magnitude more or less just by making the targets bigger. Is it conceivable that the same basic approach and a comparable amount of input energy could be used to ignite a 100 MJ or even 1 GJ target ? Of course that would present some containment challenges but perhaps not insurmountable ones. I'm also a bit concerned that this type of research may…

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.

Re: US Department of Energy: Fusion Ignition Achieved

#257

Post by dang »

Related ongoing thread:

Nuclear-fusion lab achieves ‘ignition’: what does it mean? - https://news.ycombinator.com/item?id=33971953 - Dec 2022 (82 comments)

Two threads from before the announcement:

Fusion energy breakthrough by Livermore Lab - https://news.ycombinator.com/item?id=33945863 - Dec 2022 (755 comments)

Secretary Granholm to announce major scientific breakthrough by DOE [video] - https://news.ycombinator.com/item?id=33968357 - Dec 2022 (160 comments)

Re: US Department of Energy: Fusion Ignition Achieved

#258

Post by xdavidliu »

bmmayer1 wrote: post #103
jkelleyrtp wrote: post #33

> LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE) Yesterday, everyone was complaining about the 2.2:2.0 ratio, but now we're working with 3.15:2.05. With modern lasers, that'd be a total Q of 0.375 assuming 100% ef…

This is a stupid question but I don't know anything about fusion: How is it possible for X energy to create X+Y energy in output? Doesn't that violate some fundamental law of physics?

sometimes, when two small particles fuse, they become a single larger particle, but the larger particle's mass is slightly less than the sum of the masses of the two smaller particles. The slight difference becomes energy released, and the amount of energy released, roughly speaking, is E = mc^2.

Re: US Department of Energy: Fusion Ignition Achieved

#259

Post by onlyrealcuzzo »

trillic wrote: post #57
panosfilianos wrote: post #39

I tried to do some back-of-the-envelope calculations on what this means in regards to energy costs being saved, because I couldn't find a direct source (maybe GPT could help actually). Anyway, based on ITER [1] to equate the energy production of a 1000MW coal plant you would need 2.7t of coal for that plant or 250kg of deuterium and tritium for the fusion reactor (split equally). Based on [2] deuetrium costs about ~$…

I'd imagine commodity tritium breeders would be a part of the infrastructure build out and that it will be a highly competitive space as fusion-to-the-home nears reality.

What is fusion-to-the-home?
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