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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

#571

Post by supergirl »

everyone should watch https://www.youtube.com/watch?v=LJ4W1g-6JiY to put this into perspective.

for some reason, all the news articles are extremely misleading.

previous output ratio for this fusion method was something like 70%, now it is 150%. it's a useful improvement, but not a major breakthrough. the whole system still consumes 100x more energy than it produces. 100MJ of energy is needed to power the laser. the laser generates only 2MJ of energy that powers fusion. fusion generates 3MJ of output energy. so all the articles are saying "they put 2MJ energy and got 3MJ energy back". no, they put 102MJ and got 3MJ.

Re: US Department of Energy: Fusion Ignition Achieved

#572

Post by nabla9 »

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…

3.15 Mj = 0.875 kWh

the unsolved issue with laser fusion (ICF) as an energy source is the fast degradation of high powered lasers. High powered beam degrades optics on it's path and those things are expensive. ITER has similar problem with superconducting magnets.

Re: US Department of Energy: Fusion Ignition Achieved

#573

Post by MrFoof »

pmarreck wrote: post #270
MrFoof wrote: post #220

I’m glad we might see fission power plants in my lifetime (next 30-50 years). My father still finds it novel that he basically gets to wear Dick Tracy’s watch. Yet I’m concerned that shortly thereafter, the giant robotic laser death spiders will destroy entire cities. This might also be be before we’ve built the arcologies to launch into outer space to escape the giant robot laser death spiders.

> fission power you probably meant "fusion" > My father still finds it novel that he basically gets to wear Dick Tracy’s watch. Well, except for the front-facing camera, but that's trivial to add at this point. And as a 50 year old, I agree. I feel like being incarnated in '72 has gotten me ethereal tickets to the greatest technological expansion/brouhaha in all of human history, and I don't know what my soul did to…

Yes, fusion. I 1000% blame mobile autocorrect.

> What was the movie that actually featured a scene with those, btw? I think it had Morgan Freeman

It was specifically a SimCity 2000 reference.

Re: US Department of Energy: Fusion Ignition Achieved

#574

Post by Balgair »

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 agree. This is a Big deal. Like, first-lightbulb big, or polio-vaccine big.

My kids are likely to spend the majority of their lives living a world where energy is clean, cheap, and available to everyone. Climate change is something that is not only going to be stopped, but can be reversed for them. Energy grids can be made to be smaller and mutually supporting, lessening the impacts of disasters. Oil dependency and all the political problems that come with it are going to be gone by the time they are grandparents. Nations like Nigeria and East Timor can have power generation like everyone else. The deserts and oceans and tundra of their lives will be places dotted with little greenhouses and fresh vegetables. If they get this down to the size of a car, then everything opens up for travel and recreation. The only real baseline I have to use here is Star Trek.

Of course, there is a long way to go. There is a lot of work and show-stoppers still out there. And the ideas that I see as their future are just sooooo tiny compared to their reality. I'm thinking of faster horses and they're going to live in a world of supersonic jets. That kind of difference and small thinking of mine.

I'm so happy that, assuming the best with fusion, they are going to live such better lives.

Re: US Department of Energy: Fusion Ignition Achieved

#575

Post by Analog24 »

TeeMassive wrote: post #473
davedx wrote: post #393

Earlier quoted context omitted.

We've had thermonuclear weapons (h-bombs) for a long time already. Harnessing the energy in a controlled and sustainable fashion is what's hard.

H-bombs use the hydrogen to produce more neutrons which boosts the fission process. It still is a fission bomb.

You have it backwards. The fission component is just the "trigger" for the fusion element, which produces the vast majority of the energy release.

Re: US Department of Energy: Fusion Ignition Achieved

#576

Post by moloch-hai »

CuriousCosmic wrote: post #376
sillysaurusx wrote: post #154

Earlier quoted context omitted.

It just seems a little strange to take credit for a milestone when the milestone everyone cares about is yet to be reached. (More energy out than in.) Good to hear that there's a laser design that might achieve that.

Worth noting that the milestone achieved was positive Q_plasma (more energy out of the plasma than in). They are using inefficient lasers because they are cheaper to buy/maintain/modify for research purposes. Determining the conditions for positive Q_plasma is largely a matter of science/research so the external system doesn't matter as long as the variables are controlled and results are reproducible. Once positive…

The theory was proven to everybody's satisfaction in 1950.

There will be no production, except of new, smaller thermonuclear warheads. That is their legislated remit.

Re: US Department of Energy: Fusion Ignition Achieved

#577

Post by w0mbat »

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…

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.

Re: US Department of Energy: Fusion Ignition Achieved

#578

Post by hutzlibu »

londons_explore wrote: post #399
Tuna-Fish wrote: post #363

Earlier quoted context omitted.

Inertial confinement fusion requires fairly expensive targets to collapse. To make it economically viable they have to produce a lot more energy per target destroyed.

> fairly expensive targets The targets are only expensive because they aren't produced at scale yet. They are the exact kind of thing a machine could churn millions of per day out, and then use them at the same rate. Even if the targets were made of expensive materials (eg. platinum), most of that platinum could later be recovered from the reactor wall, so it still wouldn't be very expensive.

"most of that platinum could later be recovered from the reactor wall, so it still wouldn't be very expensive. "

And recovering comes for free?

Every step costs energy (or money).

There is no working design yet. It is waay too early to make any predictions about how scaling could reduce costs. Scaling can even increase costs, if it depletes limited resources like tritium.

Re: US Department of Energy: Fusion Ignition Achieved

#579

Post by moloch-hai »

AlanSE wrote: post #424
phasetransition wrote: post #178

Earlier quoted context omitted.

Almost all nuclear weapons rely heavily on fission of the tamper for yield. Suggest "Ripple: An Investigation of the World’s Most Advanced High-Yield Thermonuclear Weapon Design" from the Journal of Cold War studies to read about a predominantly fusion device family.

This seems to say to me that D-T reactions produce neutrons, and that the kinetic energy of the neutrons is smaller than what you get by hitting U with that neutron. You already have the energy from the neutron (which will land somewhere in the system eventually), and you might as well get a multiplier by putting a blanket of U-238 in front of it. That could be carbon-copied to a fusion power plant, and indeed, there…

Since you asked: We don't build fission plants because they cost more than every other energy source. Fusion plants, if they could ever be made to work at all, would cost a lot more. So, there won't be any.

Re: US Department of Energy: Fusion Ignition Achieved

#580

Post by opportune »

Balgair wrote: post #574
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 agree. This is a Big deal. Like, first-lightbulb big, or polio-vaccine big. My kids are likely to spend the majority of their lives living a world where energy is clean, cheap, and available to everyone. Climate change is something that is not only going to be stopped, but can be reversed for them. Energy grids can be made to be smaller and mutually supporting, lessening the impacts of disasters. Oil dependency and…

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 reduced costs for industrial manufacturing. Cheap energy could make raw resource extraction much cheaper and more easily automated. Fast transportation, vertical farming. With the concurrent innovations in battery tech, robotics/automation, and electric vehicles and ships, the future is looking incredibly bright

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