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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

#751

Post by sbaiddn »

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…

TL/DR

Lasers are pretty inefficient. How much energy did it take to make 2.05 MJ of lased light?

Does this breakthrough have a reasonable path to to make more electrical energy than it puts in?

Re: US Department of Energy: Fusion Ignition Achieved

#752

Post by fastball »

chrisbaker98 wrote: post #650
antonfire wrote: post #568

Earlier quoted context omitted.

> It's a trope to say that our "best minds are working on ads". "The last generation was better because they read _books_ and had _discipline_ and didn't waste their time on frivolous garbage" is also a trope.

Doesn't mean it's wrong.

It probably is though. Sure, they didn't have as much distractions, but they also didn't have the sum total of the world's knowledge at their fingertips in the same way we do today.

People having been saying "this next generation is inferior to the last one" since the ancient Greeks. If that was consistently true we would already be in an Idiocracy scenario.

Re: US Department of Energy: Fusion Ignition Achieved

#753

Post by fastball »

asdff wrote: post #531
zizee wrote: post #511

Earlier quoted context omitted.

Are you suggesting it's all an elaborate scheme? I know it is popular/easy to hate on the man right now, but this is a really strange take. Given that Musk has been talking about mars since at least 2001, many years before he had the resources he has now, and almost went bankrupt funding spacex's first orbital rocket, it's hard to believe he's pretending. People seem happy to believe all negative things they hear abo…

The boring company was literally an elaborate scheme on the other hand. Fool me once, shame on you. Fool me, you can't get fooled again.

I dunno, if you look at the Boring Company through the lens of "this man really wants to go to Mars", it kinda makes sense. Probably a lot of Mars colony infrastructure should be tunneled underground, given the lack of atmosphere / magnetosphere.

Things like Hyperloop also make more sense in that context.

Re: US Department of Energy: Fusion Ignition Achieved

#754

Post by ajross »

galangalalgol wrote: post #581
short_sells_poo wrote: post #478

Earlier quoted context omitted.

I'm always fascinated by the sheer and unfathomable amounts of energy that is thrown around in these events. Just thinking about the fact that a single spoonful of neutron star matter contains more mass than Mount Everest fills me with wonder about the world we live in.

What happens whena tablespoon of neutron soup gets thrown out of the well of a neutron star? Does it suddenly expand to the size of everest? Where do the electrons come from?

It's essentially a giant atomic nucleus, so absent a star's worth of gravity holding it together it's going to decay rapidly into stable isotopes. So essentially it would act more or less the same as a huge fission bomb of the same mass.

Re: US Department of Energy: Fusion Ignition Achieved

#755

Post by jboy55 »

tgflynn wrote: post #733
jboy55 wrote: post #702

Earlier quoted context omitted.

It is interesting that there hasn't been many classification hurdles on something that is pretty explicitly weapons research. My guess is that they achieved high Q values a long time ago in classified research using mechanisms that would give away some secrets.

I think it's mainly because using a laser the size of a football stadium was never seen as a practical way to make a bomb.

Well, its not so much in making the bomb, but the particular ways of focusing the X-Rays and particular efficiencies in creating the tamper for the most velocity and thus most compression in the secondary.

The key thing here is the Lasers aren't doing the immediate compression, the lasers are simulating X-Ray radiation which then is ablating the casing around the tritium. Figuring out how to create and amplify a x-ray pulse was a major sticking point in the Star Wars program.

Re: US Department of Energy: Fusion Ignition Achieved

#756

Post by [deleted] »

ufmace wrote: post #586
CuriousCosmic wrote: post #344

Earlier quoted context omitted.

yes. fusion funding has been sliding downwards for decades which is a large reason why it takes so long to do anything. It's largely the same reason why NASA takes so long to do anything. 1. Shortage of funding 2. failure can result in loss/exhaustion of funding 3. extremely low risk tolerance 4. physical experiments needing new HW only happen when the likelihood of success is extremely high 5. projects are over engi…

"Funding" isn't really a good answer IMO. I don't know a ton about Fusion research specifically, but NASA is horrifically inefficient with money compared to private competitors. Giving them more money won't magically make them more efficient. Reasons why include: - Their incentive is to optimize for political approval, which means spreading facilities among as many congressional districts as possible, which creates a…

[deleted]

Re: US Department of Energy: Fusion Ignition Achieved

#757

Post by jboy55 »

moloch-hai wrote: post #736
dmix wrote: post #711

Earlier quoted context omitted.

From what I can tell this is mostly a useful cover story as a fallback for the moon-shot type energy potential. But are there serious downsides to having this be the case? Does it significantly distract away from the pursuit of energy? Or somehow fundamentally constrain the projects scope?

Exactly the opposite: their task, assigned by Congress, is weapons work . Period. But pretending to work on "carbon-free energy" is good for funding, just now . Four years ago, being all about weapons opened the tap. Make no mistake, there is no story here. There will be no "unlimited free energy" from this, or any other fusion project. The fusion startups are spending down investors' money with zero possibility of p…

At least ITER has a plausible, in a sci-fi story sense, way of creating a sustainable fusion reaction to which more fuel could be given. The fact the neutrons produced, if it did reach the high Q ratios, would irradiate and break down everything involved, is probably 2070's scientists and engineers problems to solve.

Re: US Department of Energy: Fusion Ignition Achieved

#758

Post by XCSme »

empiricus wrote: post #545

I still don't understand why we waste time and money with fusion. Fision so much easier. Should focus on it. Fusion is ok, but 100 years into the future when we are bored.

ChatGPT can answer this:

> Fission is currently the most common method of generating nuclear power, and it has been used in power plants for many years. It is a relatively well-understood technology and it can provide a large amount of energy with relatively little fuel. However, fission produces radioactive waste and the risk of accidents, such as the one that occurred at the Fukushima nuclear power plant in Japan in 2011.

> In contrast, fusion has the potential to provide even more energy than fission and it produces very little radioactive waste. It is considered a safer and more sustainable source of energy than fission.

Re: US Department of Energy: Fusion Ignition Achieved

#759

Post by kevin_thibedeau »

tgflynn wrote: post #733
jboy55 wrote: post #702

Earlier quoted context omitted.

It is interesting that there hasn't been many classification hurdles on something that is pretty explicitly weapons research. My guess is that they achieved high Q values a long time ago in classified research using mechanisms that would give away some secrets.

I think it's mainly because using a laser the size of a football stadium was never seen as a practical way to make a bomb.

It's intended to confirm computer simulations. It doesn't have to be viable for the end article.

Re: US Department of Energy: Fusion Ignition Achieved

#760

Post by naikrovek »

Retric wrote: post #743
naikrovek wrote: post #681

Earlier quoted context omitted.

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…

The paper was very clear what was involved and that information was poorly communicated. The experiment used X energy from a laser pulse to get Y thermal energy. The issue w0mbat referred to is to be self sustaining you need to use the output energy to drive the process. Aka the important number is after all relevant losses including electricity > lasers > fusion > heat > electricity, with each of those stages have l…

none of what anyone said is about a self-sustaining reaction.

this is about more power leaving the reaction chamber than what entered it. that's all the announcement is about.

this is NOT about how much energy it takes to ready the lasers. this is NOT about the electricity consumed by lighting, computers, cooling, or measurement or anything else-- none of that counts when you are measuring the efficiency of the reaction itself.

this is about more energy leaving the reaction chamber than went in.

understanding that is key to understanding the significance of the announcement, and this is significant.

and I maintain that the poster I originally called arrogant is arrogant, because they indicated in their comment that they knew how to calculate reaction efficiency better than the physicists doing the work. I called it arrogant because it is --objectively-- an arrogant position to take.

if that makes me arrogant, then so be it. my arrogance is independent of theirs and has no bearing on comments made before my own, and my comment did not influence theirs. (they were being arrogant before I pointed it out.)

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