The Science & Technology Thread

yes but that isn’t what’s happening. the “extra” energy is “stored” in the atoms already and is just being released.

like, really bad analogy is that you need a spark plug to ignite the gas in your engine

Moderna stock up 22%

https://www.washingtonpost.com/health/2022/12/13/experimental-cancer-vaccine-messenger-rna-melanoma/

So the Secretary of Energy held a press conference. At points it’s just embarrassing. To her credit, the Livermore director throws some cold water on the commercialization talk toward the end.

Today, in case the thumbnail changes:

Not quite 34 years ago:

I would just like to note that some of the same people (or their predecessors) who are hyping this result SLAMMED Pons and Fleischmann for being incompetent attention whores. I am not happy.

Anyway, good thread here:

https://twitter.com/JavierBlas/status/1602263157677985793?s=20&t=WR_dCk2jfe76eP_cCEd8gA

And not that it matters much but just for scale, the 3 MJ of fusion energy produced in the experiment is about 700 kcal, about as much as the food energy in an average American meal. Or, if I got it right, about what you need to convert a little over a liter of room-temperature water to steam.

Average meal is 700 cal, not kcal.

Edit: I stand corrected.

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dietary calorie is a kcal

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merica hater :slight_smile:

Is this the time of thing that could lead to exponential growth once they finally get “ignition” or whatever? Or is that a dumb unanswerable question?

They have “ignition” but at three times per day instead of the 10 times per second they’ll need.

It’s not a dumb question but yeah, technological progress is hard to predict. Kim Goodell is pretty frank about expectations starting at about 26:50 in the press conference video (there’s a funny moment at about 28:20 where I think she wanted to drop the mic but the Sec pushed her back up). She says “a few decades” to build power plants. I didn’t know Biden’s goal was commercialization in 10 years. C’mon, man.

I think by ignition they just mean getting fusion to occur, so that was done a while ago. From wiki, here is the energy output of past experiments:

Maybe that’s exponential? They have to get to hundreds of MJ to be in the ballpark of what’s practical.

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Would you say it’s hot fresh out the kitchen or got every man wishin?

Er no. No I wouldn’t. I have no idea what you’re talking about.

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It’s a reference to Ignition by R Kelly.

Kevin Drum put it this way:

image

No idea if he is reporting the research correctly.

.Warning: The NIF fusion facility didn’t really produce a net energy gain – Kevin Drum

So you’re saying we are still a decade away?

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But they weren’t trying to optimize the efficiency of the input power to laser setup.

Looks like after the input power, there’s the UV power, then the X-ray power, then the laser power, and then the output party.

I’ll see myself out I’m sorry.

HackerNews is having a good discussion on this.

Not sure how accurate all this is, but there are several angles hear I haven’t heard before.

But what about the remix to ignition?

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This is confusing. I can guess*, but don’t know where those numbers come from. From wiki on NIF:

The NIF became the first fusion reactor to achieve breakeven on December 5, 2022, with an experiment producing 3.15 megajoules of energy from a 2.05 megajoule input of laser light for an energy gain of about 1.5.

*My guess is that there should be another box in the path, with the final fusion energy out being 3 MJ, which was what was stated in the press conference. The missing box is the “hohlraum” that contains the small “target” bead with the D-T fuel. The laser beams impinge on the walls of the hohlraum, not directly on the target, and only about 10% of the laser energy delivered to that point actually ends up in the target.

Sabine does a good job boiling down the fusion story in the first few minutes of today’s physics news video.

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https://twitter.com/AJEnglish/status/1619455281963868161?s=20&t=tIR7LK324k16VYnMh18TXA