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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

#541

Post by OJFord »

whimsicalism wrote: post #452
OJFord wrote: post #446

Earlier quoted context omitted.

The point is to get some of it from somewhere cheaper/free - mass, or outside air as in heat pumps. You can't run your laser on mass or air, if you need a coal firing power plant to run your fusion reactor, from which you get less than you consumed from the coal plant... It's great progress, it's just not as close to viable as it might sound like - more breakthroughs needed.

I have yet to find someone saying it sounds like fusion power reactors are right around the corner, but I have found lots of people shadowboxing these people and attacking the scientists for misleading press releases. Seems like an overcorrection to something I haven't even seen anyone here say.

I think to a lot of the technically minded, but non nuclear physicists here, it initially sounded like less (paid for/electricity) energy was used than was put out. That's extremely exciting, and the actual news is still fantastic, it's just that 'actually, we needed to pay for over 100x more energy than we counted as the "input" energy [and it's possible to do 10x but not 100x better than that]' is quite a massive caveat on a 3:2 or whatever yield.

I'm not saying they've claimed anything wrong or deliberately misleading, it's just a misunderstanding/misalignment and possibly made worse by the PR teams in the middle.

In other words, I don't think it's an angry 'well actually' type correction so much as it is disappointment - it initially sounded even greater.

Re: US Department of Energy: Fusion Ignition Achieved

#542

Post by chrisco255 »

daxfohl wrote: post #517
chrisco255 wrote: post #502

Earlier quoted context omitted.

There are hundreds of years worth of oil deposits (possibly more) even at current usage rates. "Selling all the oil" isn't in the realm of possibility.

Still, as much as possible before the party is over.

As much as necessary, sure. Oil it turns out is pretty useful in many different industries and contributes to higher standards of living for the vast majority of the world. It isn't some inherently evil technology or resource. Still, it's going to take decades to transition to electric regardless of any breakthroughs in the meantime.

Re: US Department of Energy: Fusion Ignition Achieved

#543

Post by seandoe »

mlindner wrote: post #434

The design of the National Ignition Facility was never intended to study commercially viable fusion power. It's exclusively a physics testing facility with origins for testing the physics of thermonuclear fusion weapons for better bomb design. Nothing that happens at the NIF is very useful in heading towards commercially viable fusion. The design of the testing apparatus is also similarly incompatible with making a s…

Swaying public perception in an optimistic direction is enough of an effect to justify the cost and effort of this achievement.

Re: US Department of Energy: Fusion Ignition Achieved

#544

Post by LarryMullins »

nerpderp82 wrote: post #536
ClumsyPilot wrote: post #505

Earlier quoted context omitted.

There are like 20 designs of various fusion reactors on the drawing board that need to be built and tested. Scientists also don't work for free. They arent mushrooms that grow by themselves

One of the things that I think I noticed from the press conference, is that funding is going to be the bare minimum to meet some goal for a design they select. This seems like a gross mistake. If we are going to avert a climate catastrophe we will need TW of power to "unburn" the carbon we put into the environment (ocean and atmosphere). Instead of barely hitting this target, we should over deliver since we are runni…

Dump trillions of dollars into fusion energy today and it will still be decades before the first fusion power plant is connected to the grid. You'd be better off funding the construction of fission power plants. Those are very expensive and take years to build, but they're still a hell of a lot cheaper and faster than funding fusion to the degree you're suggesting.

Re: US Department of Energy: Fusion Ignition Achieved

#546

Post by mbauman »

BadBadJellyBean wrote: post #506
twic wrote: post #429

Earlier quoted context omitted.

Take spullara's numbers: 2.01410177811 u = 3.34449439340696e-24 g deuterium 3.01604928 u = 5.008267217094e-24 g tritium 17.6 MeV = 7.832863e-19 kWh energy Divide through, and you will see that you need 4.27 ug/kWh of deuterium, and 6.39 ug/kWh of tritium. A random source [1] says that New York will use 50.6 TWh per year by 2027. That would require ~216 kg/yr of deuterium and ~323/yr kg of tritium. This is all assumin…

I wonder if that is much or not. I have no idea how hard this is to produce. Do you have an idea about that?

Oooof, looks like the primary way of creating it is through... fission reactors.

https://en.wikipedia.org/wiki/Tritium#Production

And there's not much of it:

> According to a 1996 report from Institute for Energy and Environmental Research on the US Department of Energy, only 225 kg (496 lb) of tritium had been produced in the United States from 1955 to 1996.[a] Since it continually decays into helium-3, the total amount remaining was about 75 kg (165 lb) at the time of the report.

Re: US Department of Energy: Fusion Ignition Achieved

#547

Post by empiricus »

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.

Actually just a rhetorical question. We are so irational that fusion makes perfect sense.

Re: US Department of Energy: Fusion Ignition Achieved

#548

Post by LarryMullins »

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...

That's just the lasers, the rest of the plant needs power too. Big water pumps are big power hogs, as is the rest of the supporting equipment that any power plant requires to operate. Far over "wall plug" break even is required for commercial viability.

Re: US Department of Energy: Fusion Ignition Achieved

#549

Post by zardo »

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…

The targets are really the secret sauce right? If there were a civil ICF for power program, would NIF designs and data even be available to help, or is it all classified?

Re: US Department of Energy: Fusion Ignition Achieved

#550

Post by phtrivier »

adventured wrote: post #427
phtrivier wrote: post #215

Since I absolutely decided to take this in the worst possible way (get the downvotes ready) What is the timeframe for those lasers to light a bulb somewhere, vs the timeframe of those lasers killing someone on a battlefield ? (As in, how much of is applicable for the military?)

I'm not sure what you're talking about. What is it you think you took in the worst possible way? The lasers in question are mediocre for battlefield use. The consequences for the military are trivial, unless you're talking about 70 years from now when the US military is using fusion to power some of its military bases, subs or carriers.

I decided to take this "fusion breakthrough" with a massive dose of salt additionned with twice it's weight in pepper and bile.

At least the Nature article had a good ratio of actual information about the experiment, its limitations and prospect, as opposed to massive hyperbole from other commenters already popping the champagne as if the energy crisis was over.

This made sound grumpy, which, truth be written, I am.

(And, jealous, too, of course. I wouldn't mind a bit of actual success, once in a while.)

Or maybe the grunts working on the experiment know better, and are _also_ grinding their teeths at the PR effort ? Maybe _they_ also feel unsatisfied because they still haven't met their own goal ? I suppose nuclear fusion physicists must have imposter syndrome, too ? Who knows.

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