Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab • Hacker News Board

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#461

Post by pfdietz » Wed, Oct 13, 2021, 9:15 AM UTC

thehappypm wrote: post #430

Robotbeat wrote: post #211

Earlier quoted context omitted.

It’s actually frozen deuterium tritium. Inside a small pellet blasted by X-rays which compress the pellet until it’s hot and dense enough for the fusion energy produced to continue burning and heating the deuterium/tritium until much more energy is produced than the energy of the X-rays. It all happens in an instant. The pellet’s structure doesn’t survive. But it happens fast enough that just the inertia of the pelle…

How do you freeze hydrogen?

You make it very cold.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#462

Post by pfdietz » Wed, Oct 13, 2021, 9:16 AM UTC

ourmandave wrote: post #406

Fusion is the fuel of the future - and it always will be.

Unlikely. At some point, the meme will just sputter out. Fusion will be as much the energy source of the future as dirigibles will be the aircraft of the future.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#463

Post by tsimionescu » Wed, Oct 13, 2021, 9:27 AM UTC

Iv wrote: post #443

tsimionescu wrote: post #110

Earlier quoted context omitted.

ICF really doesn't have this potential, definitely not in the way it is practiced here. Each shot at NIF costs a few million dollars in material costs alone, because of the precisely machined parts that are required to achieve inertial confinement of the plasma long enough to make it start fusion, which get destroyed in the process.

This was a 50 years project because huge installations need to be built in order to gain knowledge about different technologies and aspects of fusion. The goal of these experiments is to achieve fusion power plants. ITER is probably going to be the first large scale demonstration, though I would not rule out an unexpected innovative design to pass it at one point.

The goal of NIF is weapons research, not fusion power (though their technology can in principle be used for fusion power as well, albeit extremely unlikely to be economical).

ITER is indeed aimed at studying fusion for power generation. It's important to remember though that even if ITER reaches its stated goal, it will not generate even one milliwatt of power - it will in fact consume much more power than it can generate. In fact, they are so far from net power generation that they didn't even bother to try to extract any usable power from the plasma - it wasn't even worth it to add turbines.

DEMO will be the "project" to try to obtain positive net power from plasma (it's not a project, it's just a concept that several countries aim to separately execute on, unlike the international collaboration of ITER). And the timeline for any DEMO net power generation is estimated at 30 years after ITER is successful - so 2050+ IF both ITER and DEMO achieve their expected timelines perfectly.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#464

Post by dreamcompiler » Wed, Oct 13, 2021, 10:22 AM UTC

Animats wrote: post #133

Oh, this is just laser fusion. One pulse of power. That's not a power source, even potentially. It's a lab-sized H-bomb experiment. This isn't one of the magnetic containment systems achieving ignition and sustaining the reaction. Now that would be an achievement.

Well...yeah. The national labs do fusion experiments because they can't do bomb tests any more. (It's also the reason they tend to have the biggest supercomputers in the world, so they can simulate nuclear explosions.) But that doesn't mean they don't learn things that might be useful for energy production.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#465

Post by [deleted] » Wed, Oct 13, 2021, 10:36 AM UTC

smaddox wrote: post #402

ClumsyPilot wrote: post #371

Earlier quoted context omitted.

The capsules are tiny and do not generate usefull amount of energy. ITER is planned to generate 500,000,000W. Thats actually usefull

1 MJ is enough to vaporize roughly half a liter of water that started at room temperature. That's nothing to sneaze at. Obviously you would need to do with a high rate (e.g. once per second) in order for it to be viable for power production. No reason the lasers couldn't do that. The challenge is making the pellets cost effective at scale. Currently, they cost something like $10k each.

[deleted]

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#466

Post by Qwertious » Wed, Oct 13, 2021, 10:59 AM UTC

Andrew_nenakhov wrote: post #333

Qwertious wrote: post #306

Earlier quoted context omitted.

>Living creatures are a source of CO2 too, and a big one. Look up for a share of greenhouse gases coming form agriculture. CO2 emitted by horses comes from the food they eat, which is absorbed from the atmosphere in the first place by the plant when it grows. And a ton of the greenhouse gases from agriculture come from using oil, a major component of that being from tractors and crop dusters (which wouldn't exist in…

No, not really. [1] [1]: https://timeforchange.org/are-cows-cause-of-global-warming-m...

That's methane, I was addressing CO2.

But to address methane: That's cows not horses. Cows produce far more methane than horses.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#467

Post by Robotbeat » Wed, Oct 13, 2021, 12:48 PM UTC

smaddox wrote: post #402

ClumsyPilot wrote: post #371

Earlier quoted context omitted.

The capsules are tiny and do not generate usefull amount of energy. ITER is planned to generate 500,000,000W. Thats actually usefull

1 MJ is enough to vaporize roughly half a liter of water that started at room temperature. That's nothing to sneaze at. Obviously you would need to do with a high rate (e.g. once per second) in order for it to be viable for power production. No reason the lasers couldn't do that. The challenge is making the pellets cost effective at scale. Currently, they cost something like $10k each.

It’d have to be dozens or even hundreds per second, like an internal combustion piston engine.

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#468

Post by gmadsen » Wed, Oct 13, 2021, 1:17 PM UTC

humaniania wrote: post #102

rfrey wrote: post #61

Meta-question about fusion energy -something I don't understand about the movement. I spent a few years as CTO of a company providing heat-to-electricity plants. We financed and built them off high-heat plants like natural gas turbines. The "fuel" was heat going up the stack - so it was essentially free. We still couldn't compete with conventional electricity plants, even with a $30/tonne price on carbon in Canada. G…

Natural gas is only inexpensive because of fracking. With fracking in the USA at least the people involved can set up an LLC that dissolves after the well runs out. They are not required to disclose the contents of the fracking wastewater fluid. It gets pumped back down underground where it could dissipate into the rest of the water system. These people claim that it's safe for decades when our computer models can't…

while I agree with the sentiment, your analogy about weather is misplaced.

We can model the climate decades into the future, which this situation seems more similar to. Obviously the fracking companies would be biased, so I am not siding with them, just that particular argument feels like a straw man

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#469

Post by marktangotango » Wed, Oct 13, 2021, 2:44 PM UTC

cletus wrote: post #322

marktangotango wrote: post #299

Earlier quoted context omitted.

> I firmly believe that space-based solar power collection is our most likely future. Isn't this the same capital expenditure analysis your post starts with though? How many billions does it cost to get the solar panels to orbit in sufficient quantity? And ground stations to receive the energy beams (microwave presumably). This is where Musk/Spacex push for cheap kg to orbit really matter. Even in the 70's they worke…

So during the Space Shuttle (and earlier) era I believe the cost of getting payloads to LEO was $20-50k/kg. Currently with Falcon 9 it's gone down to ~$1000/kg. I imagine this will continue to get cheaper with further reuse and Starship. But we really need to get down to Imagine being able to take a cable car into orbit. That's what orbital rings promise and you need little more than copper wire and stainless steel.…

Ha, I had not heard of orbital rings yet, thank you. My comment there is "who will think of the children/astronomers" parodying the simpsons. Although that applies space elevators as well.

https://www.youtube.com/watch?v=RybNI0KB1bg

Re: Major nuclear fusion milestone reached as ‘ignition’ triggered in a lab

#470

Post by SuoDuanDao » Wed, Oct 13, 2021, 3:09 PM UTC

xondono wrote: post #451

SuoDuanDao wrote: post #368

Earlier quoted context omitted.

I hope we could agree though, that the cost of switching to renewables too early is negligible compared to the cost of switching too late. If that can be agreed on by all, the relevant questions are 1) when do we think it would be too late? 2) how certain are we of that date? 3) how long will it take to switch to renewables? and 4) How certain are we of that date? I don't disagree with your basic premise. Personally…

> that the cost of switching to renewables too early is negligible compared to the cost of switching too late. Smaller yes, but I wouldn't call it negligible. > the more the economy grows before the switch to renewables is complete, the harder it becomes to make the switch. That one I think you got reversed. Think that one through, the economy now is way greater than it was in 1980, do you really think we were better…

>That one I think you got reversed. Think that one through, the economy now is way greater than it was in 1980, do you really think we were better prepared for the switch back then?

I wasn't clear. We become better prepared to switch but the switch itself becomes harder. The 1980 economy was smaller, therefore it would have required fewer renewable energy sources to replicate using only renewable energy. Sure, renewable energy is more available today than in 1980, but that's due in large part to people since 1980 being willing to invest in something other than fossil fuels, despite the lower margins.