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US Department of Energy: Fusion Ignition Achieved

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Re: US Department of Energy: Fusion Ignition Achieved

#371

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we are all made of star stuff

or as I like to say to encourage myself that small things matter "Stars are made of quarks"

What are quarks made of?

https://static.wikia.nocookie.net/memoryalpha/images/d/d9/Qu...

Re: US Department of Energy: Fusion Ignition Achieved

#372

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…

Do we know how much tritium is needed for a city's energy generation? What about a state etc? Reason I ask is the only uses I have seen for tritium is on old watch dials made in the pre-90's. Curious how much of this resource is out there.

Re: US Department of Energy: Fusion Ignition Achieved

#373
post #163

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Imagine if Musk spend 44 Billion fusion

Given it's Musk and his stated primary life goal, the most ridiculous aspect of the Twitter debacle for him, is: not only of course did he overpay for Twitter by at least 2x; not only is his net worth going to contract as Tesla's stock compresses (such that the poor Twitter decision is going to be that much more painful in relation to his overall wealth); but the $40x billion could have probably paid for getting Star…

>the $40x billion could have probably paid for getting Starship to Mars.

Maybe he doesn't actually believe in Starship.

Re: US Department of Energy: Fusion Ignition Achieved

#374
post #256

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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.

The advantage would be that you wouldn't need tightly controlled and hard to make materials like U-235 or Pu to make one. I'm not in any way saying that using lasers would be a plausible route to such a weapon, since the NIF facility is huge, but if it turns out that the research needs to focus on how to get more output per shot, which I think it inevitably would since a typical conventional or nuclear power plant ge…

Shiiiit... here I was thinking how cool it would be if they could miniaturize this, having somehow forgotten that my pet solution to the Fermi paradox is that a nigh-inevitable wrung on the ladder to interstellar presence involves discovering One Weird Trick to release a whole bunch of energy pretty easily, even on a DIY basis. Instant end of civilization. Even ant-like societies might have mutated members who'd go rogue and misuse the tech, and it wouldn't take many to ruin everything.

Basically it's a twist on the ice-9 solution to the paradox.

Re: US Department of Energy: Fusion Ignition Achieved

#375
post #241
post #40

Remarkable. It's still nuclear energy, and the sobering part for me is that fusion neutrons are an order of magnitude more energetic than fission neutrons. Add the fact that fusion plants are an order of magnitude larger, and you get orders of magnitude more nuclear waste with order of magnitude higher activation/radioactivity. If you don't like nuclear for these reasons, you'll probably hate fusion.

https://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect

I have a PhD plasma physics, I think I am qualified to make these statements without this sort of dismissal!

Re: US Department of Energy: Fusion Ignition Achieved

#376

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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.

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 Q_plasma is well understood/reproducible, achieving positive Q_total (more energy produced than spent running the infrastructure) is just a matter of engineering and potentially waiting for the SOTA for components (like lasers or materials) to catch up.

TLDR: This is the scientists proving the theory. Now it's the scientists' job to refine the theory. Then the engineers get to put it into production.

Re: US Department of Energy: Fusion Ignition Achieved

#377
post #315

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Thanks a ton for that! $25/MWh is great but not the 10x economic impact I expected. Especially since [1] we see PV at $50/MWh currently. [1]: https://en.wikipedia.org/wiki/Cost_of_electricity_by_source

The economic impact doesn't just come from the fuel to energy ratio. One of the biggest differences is also in the space required. Nuclear fusion reactors could eventually end up being very small - like smaller than an SUV. Imagine the cost savings in miniaturizing electrical grids.

if they can be that small then they might find unexpected use in long range spacecrafts or lunar colonies. you'd still have to build and lift the reactor out of earths gravity well.

Re: US Department of Energy: Fusion Ignition Achieved

#378
post #94

I like how over 60 years after the nuclear boom, it somehow just happened to happen today. Just when the world is ready to transition to electric vehicles on a global scale, just when oil companies aren't able to make as much money from oil as they used to, just when one of the major suppliers of fossil fuels (Russia) is at war with the West, it has somehow magically happened. What a coinky-dink. Throw lots of money…

> I like how over 60 years after the nuclear boom, it somehow just happened to happen today. Just when the world is ready to transition to electric vehicles on a global scale, just when oil companies aren't able to make as much money from oil as they used to, just when one of the major suppliers of fossil fuels (Russia) is at war with the West, it has somehow magically happened. What a coinky-dink.

It would be coincidental timing, if the most breathless headlines were actually true. But in reality we're still decades away from commercially viable fusion power generation. A fusion energy gain factor of Q=1 is little more than a psychological hurdle. Imagine you have a process that consumes 1 gigawatt of power and produces 1 gigawatt + one additional watt of power; that's Q=1. And it's certainly not commercially viable.

Re: US Department of Energy: Fusion Ignition Achieved

#379

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.

Don't take it too personally, but you, and many others here, need to rethink their approach. You see a short tweet without context about a topic you clearly know nothing about (which is totally, fully okay, it's a complex topic), and think you are now able to criticize milestones in this impossibly complex topic. Not even ask questions, not something like "hey, I saw this tweet, I know it's just a tweet, but can some…

No thanks.

I get that people are emotional about this, but it’s important to treat science with a critical eye.

The claim is that more energy came out than was put in. This is false.

It’s not just me saying it. https://www.tiktok.com/t/ZTRVP5Pmg/

There is no “context” to understand. Yes, it’s an impressive feat. Yes, other laser designs might fix the huge ignition costs. But that hasn’t happened yet, and until it does, it’s completely fair to point that out.

Will it win me any friends? Probably not. It’s like showing up to a party and saying the reason for the party is mistaken. Very few people care.

But scientists should, and I am one. Doubly so for incorrect reporting to laymen. We have a responsibility to convey what was actually achieved, not what we wish was achieved.

Re: US Department of Energy: Fusion Ignition Achieved

#380

Earlier quoted context omitted.

That's a circular argument. It's big because the people doing it call it big. Why should I, an outsider, care about their internal goals, their egoes, or their status in their field? What does it do or imply for me?

To achieve fusion for power production, you need more output than input. For 60+ years this hasn’t been achieved in a replicated fashion. Now it has, and it’s 50% more power rather than 0.1% more power as was sometimes shown for 2 nanoseconds before. So now we know fusion for power is possible. If it can be scaled successfully (now likely not an if anymore, but a function of time), then we have the ability to have cl…

I'm asking why this somewhat arbitrary line being crossed is something I should care about. It doesn't imply fusion will reach a state of practical application. Why is this more exciting that achieving a ratio of .1, or .5, or 2, or 10? It seems entirely arbirary to me, and smells of an argument that somehow this has made the end goal significantly more attainable.
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