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Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

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Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#51

Post by oblio »

Systemic33 wrote: post #50
rob74 wrote: post #43

Still unconvinced why this is such a major breakthrough - it may be the first net-positive controlled fusion, but the distinction between controlled and uncontrolled fusion is a bit academic in this case. In uncontrolled fusion ( https://en.wikipedia.org/wiki/Thermonuclear_weapon ), you are using a nuclear fission primary stage to generate enough energy to start the fusion reaction in the secondary stage. In the NIF,…

With regards to NIF being a military facility, I'd very much think that energy production (cheap, safe, limitless?) is very much a military needs as much as a civilian need. Even if said energy goes further to power laser weapons or other exotic power hungry systems; energy is energy, and something has to produce it.

The internet was a military need from what I remember.

The military said something like: "Telephone routing is point to point and inflexible, if the enemy cuts out 1-2 lines of communication, an entire section is completely cut off. We need something better." That something better turned out to be packed switching where you just throw stuff along a network and the network ensures that the packet reaches the destination, but you could theoretically have two packets going from Bucharest to Johannesburg, one through India and the second one through Canada.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#52

Post by oblio »

skelpmargyar wrote: post #17
garyclarke27 wrote: post #9

Most interesting fact from the article. At the system level it took 300 million Joules to produce 3 Million a 1% return - so still a very long way to go! With this kind of approach I can’t see how fusion can ever be cheap, the capital costs are enormous. Better to focus on standardised production lines for small fission reactors.

It's better to focus on standardised production lines for small fission reactors currently if your goal is to produce energy for the power grid right now, but that's not what cutting-edge research or science is about. Whoever launched the first firework probably didn't see how people could walk on the moon either. Science is rarely a linear path. It's also rarely "I have this problem so I solved it this way." That's…

Nuclear fusion is stuck into an "early MASER/LASER phase".

Laser was cool, but nobody knew what to do with it. These days we're at the stage where we're thinking: what can't we do with it??? But for about 3 decades (before CDs, basically) laser was a pop science laughing stock, more or less.

And fusion is much harder plus has been talked about and hyped for at least as long.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#53

Post by moffkalast »

albertopv wrote: post #22

Real Engineering published a video about Helion Energy company. I don't have the tools to filter out commercial BS, still it seems to me to be most promising effort. The idea to get electricity directly from magnetic fields instead of boiling water is very intriguing.

I've also been quite surprised watching that one, it's completely novel approach to fusion and it may be the best way to mass adoption.

If they can make it work that is.

What most surprised me about NIF's ignition announcement was that this was even news. I'd assumed for years that most if not all tokamaks and stellerators could already achieve at least some brief fusion, just not to a useful degree. Turns out they're all just elaborate plasma heaters...

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#54

Post by noobermin »

oblio wrote: post #51
Systemic33 wrote: post #50

Earlier quoted context omitted.

With regards to NIF being a military facility, I'd very much think that energy production (cheap, safe, limitless?) is very much a military needs as much as a civilian need. Even if said energy goes further to power laser weapons or other exotic power hungry systems; energy is energy, and something has to produce it.

The internet was a military need from what I remember. The military said something like: "Telephone routing is point to point and inflexible, if the enemy cuts out 1-2 lines of communication, an entire section is completely cut off. We need something better." That something better turned out to be packed switching where you just throw stuff along a network and the network ensures that the packet reaches the destinati…

That said while the intent the current internet is pretty centralized at least in some senses.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#55

Post by oblio »

ly3xqhl8g9 wrote: post #44
fragmede wrote: post #33

Earlier quoted context omitted.

Transistors? Computers before them used vacuum tubes. In 1943 Thomas Watson, chairman of IBM, said, "I think there's a world market for maybe five computers." Now, it would be easy for us to laugh at him, thanks to us being almost 80 years in the future, but on the topic of "what does the future hold for us", put yourself in Watson's place. You're reasonably smart and knowledgeable, and understand what goes into a co…

Thomas Watson's quote is misrepresented and it is more prescient than it appears. There are indeed maybe five computers on the world market: the BlackRock computer [1], the Google computer, the Tencent computer, and maybe a few others. A computer can be implemented in one CPU, or in millions of CPUs: if the control and the data ownership behind the CPUs is the same, it is still one computer. Watson's quote is more ab…

> Watson's quote is more about psychology rather than technology, just look at the hullabaloo of crypto: a theoretically decentralized technology and the people still use centralized exchanges.

Well, that's easy. I forgot who mentioned it, but crypto has 0 support for actual clients, and the vast majority of day-to-day computing now happens on mobile end user devices (phones, tablets, laptops). So besides (what should be) this fatal flaw, the second thing crypto requires you is to manage your keys SUPER carefully yourself or a server.

Nobody[1]'s going to do that. I'm a techie and I don't want to maintain my own servers. What hope does Joe Locksmith have?

So in practice crypto will always centralize.

[1] 99% of the population.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#56

Post by bawolff »

graderjs wrote: post #49
bawolff wrote: post #47

Earlier quoted context omitted.

Humans usually do the cheap thing. Historically making the right thing the cheap option has been much much more effective than trying to nag the invisible hand, which basically never works.

It's not the point, having cheaper energy is not going to magically reverse priorities. Focus on what's important. Anyway, you work it out. I'm not gonna waste my time having a discussion here.

Who cares what the priorities are as long as the right result happens? If cheap energy makes incentives align so the right outcome happens, why does it matter the wrong priority caused that outcome.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#57

Post by albertopv »

moffkalast wrote: post #53
albertopv wrote: post #22

Real Engineering published a video about Helion Energy company. I don't have the tools to filter out commercial BS, still it seems to me to be most promising effort. The idea to get electricity directly from magnetic fields instead of boiling water is very intriguing.

I've also been quite surprised watching that one, it's completely novel approach to fusion and it may be the best way to mass adoption. If they can make it work that is. What most surprised me about NIF's ignition announcement was that this was even news. I'd assumed for years that most if not all tokamaks and stellerators could already achieve at least some brief fusion, just not to a useful degree. Turns out they'r…

I'm very skeptical about those great announcements, even more when there's an announcement of the announcement. 300MJ in, 3MJ out, I wouldn't call it a breakthrough, maybe a milestone, nothing more.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#58

Post by vesinisa »

bawolff wrote: post #39

Everything i have heard about this makes it sound more like a milestone than a breakthrough. I.e. its great it happened and an important step, but its not shocking that we eventually did it. When i hear breakthrough i think of something more unexpected. I.e. figuring out how to solve a problem we had no idea how to solve.

Exactly.. The article fails to answer the question posed by its very title. What I've gathered, this was a very much expected result and NOT a "breakthrough". And with regards to making fusion a viable source for commercial, large-scale energy production .. this is only tangential at best to that effort.

The problem with celebrating "fake victories" (and being scolded for calling them out) is that when there really is a breakthrough (i.e. something so big it fundamentally changes our perception of the problem), people are going to think you are making just another over-hyped publicity stunt. I am definitely of the opinion that such media attention focused advertising of (otherwise perfectly valid) fundamental research is doing no one favors (not the researches nor the public.)

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#59

Post by danbruc »

tmikaeld wrote: post #12
garyclarke27 wrote: post #9

Most interesting fact from the article. At the system level it took 300 million Joules to produce 3 Million a 1% return - so still a very long way to go! With this kind of approach I can’t see how fusion can ever be cheap, the capital costs are enormous. Better to focus on standardised production lines for small fission reactors.

For one, it's theoretically impossible to make lasers 102 times more efficient, especially if you consider the current industrial efficiency of up to 20% (30% under special conditions). For example, the maximum efficiency of a laser is limited by the quantum efficiency of the laser material, which is the ratio of the number of photons emitted by the laser to the number of charge carriers (electrons and holes) injecte…

For one, it's theoretically impossible to make lasers 102 times more efficient, especially if you consider the current industrial efficiency of up to 20% (30% under special conditions).

That is not true. You can of course not make a 10 % efficient laser more than 10 times more efficient, but there is no limit to how much more efficient you can make a laser in general, you just have to start with an inefficient enough one.

And the NIF lasers are quite inefficient, according to Wikipedia - which might have slightly outdated numbers as someone pointed out to me - they turn 422 MJ stored in capacitors into 1.8 MJ UV laser light, that is an efficiency of 0.43 %. Bringing this up to the 20 % you mentioned would already almost be a factor of 50. Also not all of the gain has to come from more efficient lasers, the fusion process could also be made more efficient.

But you are of course correct that there is some general limit to laser efficiency, therefore the question is if the fusion gain can compensate this and all additional losses during the conversion into electricity further down the line.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#60

Post by hoseja »

moffkalast wrote: post #53
albertopv wrote: post #22

Real Engineering published a video about Helion Energy company. I don't have the tools to filter out commercial BS, still it seems to me to be most promising effort. The idea to get electricity directly from magnetic fields instead of boiling water is very intriguing.

I've also been quite surprised watching that one, it's completely novel approach to fusion and it may be the best way to mass adoption. If they can make it work that is. What most surprised me about NIF's ignition announcement was that this was even news. I'd assumed for years that most if not all tokamaks and stellerators could already achieve at least some brief fusion, just not to a useful degree. Turns out they'r…

They basically have no real achievements yet - the energy harvesting system isn't working, they are just fusing D+He3 - even though the concept sounds impressive. The video was cool but not cool enough to break through healthy fusion vaporware skepticism.
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