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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

#221

Post by dgacmu »

spullara wrote: post #113
tgflynn wrote: post #111

Earlier quoted context omitted.

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 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/Thermonuclear_weapon

Re: US Department of Energy: Fusion Ignition Achieved

#222

Post by dontwearitout »

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?

Fission's amazing potentially is nerfed by three main things: proliferation risk, meltdown risk, and waste handling. These are all solved problems but dramatically raise the cost (you need armed guards, and the reactor has to be built to withstand a 747 strike, etc etc). The fuel cost is a very small fraction of the price of nuclear.

If you can eliminate or reduce the need for armed guards and mountains of red tape, this has the potential to solve many of fission's problems while providing the same benefits (unlimited zero carbon power with dirt cheap fuel).

Re: US Department of Energy: Fusion Ignition Achieved

#223

Post by saul_goodman »

frellus wrote: post #66

I hate to ask this, but have to ... is there any danger of these discoveries being weaponized easily by hostile countries? i.e. does this make unconventional weapons more accessible to countries who otherwise have embargoes on technology and material to make atomic weapons?

You have to remember that all of the classified details about US hydrogen bomb designs we have were leaked from leaked from Russia after the Soviet Union broke apart. And yet only two countries have managed to become nuclear states since then (Pakistan and North Korea).

It's the engineering that makes nuclear weapons hard to do, not the knowledge.

Re: US Department of Energy: Fusion Ignition Achieved

#224

Post by drusenko »

JohnBerea wrote: post #100

Let's say this all works out and over the next few decades fusion replaces all other electricity generation, and we're past the point where all the initial infrastructure costs have been paid for. How much will my electric bill be reduced?

If you live in California, even if electricity generation cost nothing at all it would still only lower your bill by ~15%. Transmission & distribution of electricity is the expensive part not generating it. It doesn’t need to be expensive, yet here we are.

Re: US Department of Energy: Fusion Ignition Achieved

#225

Post by pohl »

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 ~$…

No post body was provided.

Re: US Department of Energy: Fusion Ignition Achieved

#226

Post by [deleted] »

brianyu8 wrote: post #209
dleslie wrote: post #182

Earlier quoted context omitted.

The question on my mind is: where do I sign up to join this effort?! Edit: I'm Canadian, the question is rhetorical.

Assuming you have experience in software, then https://www.llnl.gov/join-our-team/careers/find-your-job/0d6...

[deleted]

Re: US Department of Energy: Fusion Ignition Achieved

#227

Post by dogma1138 »

jeffbee wrote: post #128
dogma1138 wrote: post #13

Earlier quoted context omitted.

Because now it’s reproducible, controllable and consistently net positive in terms of energy output. It’s not a fluke anymore and I assume the engineering behind this is now understood well enough to develop it further and scale it up. Fusion for the most part isn’t a physics problem it’s an engineering problem the difficulty was always in how to implement it in the real world rather than in math at ideal white paper…

What information available to the public suggests this is reproducible and consistent? They do hundreds of shots every year. Why do we think that this energetic shot wasn't just a result of getting luckier this time than they did a few years ago?

Because the press release stated that they’ve ramped up the reaction and got higher energy output and the scaling wasn’t linear in a good way.

Re: US Department of Energy: Fusion Ignition Achieved

#228

Post by aaroninsf »

spullara wrote: post #165
bmmayer1 wrote: post #103

Earlier quoted context omitted.

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?

If you look at the mass before of their fuel, 1 deuterium atom + 1 tritium atom: 2.01410177811 u + 3.01604928 u = 5.03015105811 u vs the mass of the fusion products of 1 helium atom and 1 neutron: 4.002602 u + 1.008 u = 5.010602 u You'll notice that even though we started with 5 neutrons and 2 protons and ended up with the same number there was some additional binding energy that is unaccounted for in the new configu…

This is an A+ comment—helpful, well-formatted, concise, with bonus interesting additional detail.

Thank you.

Re: US Department of Energy: Fusion Ignition Achieved

#229

Post by jameshart »

frellus wrote: post #74
frellus wrote: post #66

I hate to ask this, but have to ... is there any danger of these discoveries being weaponized easily by hostile countries? i.e. does this make unconventional weapons more accessible to countries who otherwise have embargoes on technology and material to make atomic weapons?

Oops, answered my own question I guess: https://en.wikipedia.org/wiki/Pure_fusion_weapon That ain't good. Although fusion is clearly the future of energy, we have to get our sh*t together on earth so we don't kill ourselves off or devolve with endless wars. Or give up and use fusion to leave the planet efficiently.

From your wiki source:

> The power densities needed to ignite a fusion reaction still seem attainable only with the aid of a fission explosion, or with large apparatus such as powerful lasers like those at the National Ignition Facility, the Sandia Z-pinch machine, or various magnetic tokamaks. Regardless of any claimed advantages of pure fusion weapons, building those weapons does not appear to be feasible using currently available technologies

Nothing about this result from NIF seems to suggest that igniting fusion is any easier than previously suspected.

Re: US Department of Energy: Fusion Ignition Achieved

#230

Post by bitcurious »

brofallon wrote: post #30

I'm still a little unclear on the benefits that fusion offers compared to things like wind and solar. I understand that we need to develop better storage technologies for the energy produced by wind and solar, but that seems so much easier than the challenges currently facing fusion. Wind and solar just seem so far ahead of fusion already - they're pretty cheap and very widely deployed on a global scale. In compariso…

Wind and solar have a max theoretical output that is constrained by physical space and competition for its use, in addition to weather patterns, etc.

Fusion energy has a theoretical max that’s orders of magnitude higher.

Wind+solar is the path to decarbonization and sustaining our current world.

Fusion is the path to post scarcity. If/when we get scalable commercial fusion, it’ll be like the transition to oil - society will radically change, in ways we can’t predict.

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