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Germany is turning on its monster stellarator

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Re: Germany is turning on its monster stellarator

#101

Post by jpadkins »

saalweachter wrote: post #32
lucaspiller wrote: post #28

Assuming these experiments work as desired and this reactor can produce more energy than it takes in, how long will it be (roughly) until a power plant becomes operational (i.e. connected to the grid) that uses this technology? Years, a decade, many decades?

5-10 years is the classic naive/huckster estimate. 30-50 years is the respectable man's "I have no idea" estimate for anything.

We used to build cathedrals that took 3 generations of masons. Imagine working on a design that your granddaughter would see the launch of...

Re: Germany is turning on its monster stellarator

#102

Post by joelberman »

Practicality wrote: post #89
balabaster wrote: post #83

Earlier quoted context omitted.

Dude... refactor that shit. There is no place in today's development world that a 1500 line function is okay :P

Indeed. It will save you from needing inspiration to debug it as well. It's much less cognitive load when you break those crazy things into understandable parts.

The potential speedup on those old F2C routines is amazing. The ability to use much more memory, understand cache levels, etc. have a huge impact.

Re: Germany is turning on its monster stellarator

#103

Post by ihsw »

justifier wrote: post #87
jakeogh wrote: post #11

Wendelstein 7-X - from concept to reality: https://www.youtube.com/watch?v=lyqt6u5_sHA Im Zeitraffer: Zusammenbau von Wendelstein 7-X: https://www.youtube.com/watch?v=MJpSrqitSMQ (best @ 0.56x) Previously: https://news.ycombinator.com/item?id=10437075 More: https://www.youtube.com/channel/UCAx243-m51RI-k_4lsAqidA/fee...

the first video claims a magnetic field strength of 2.5 Tesla(o) roughly that of an MRI(i) can anyone speak to sort of considerations that lead to this value? 2.5T seems insignificant considering the events it will be confining how sensitive is the field to magnetic interactions outside of the device? (o) https://youtu.be/lyqt6u5_sHA?t=301 (i) https://en.wikipedia.org/wiki/Tesla_(unit)#Examples

Probably for each magnet, of which there are fifty.

And considering these devices are heavily shielded, I would doubt there would be much interaction outside.

Re: Germany is turning on its monster stellarator

#104

Post by annnnd »

fsloth wrote: post #96
balabaster wrote: post #83

Earlier quoted context omitted.

Dude... refactor that shit. There is no place in today's development world that a 1500 line function is okay :P

Not all functions are refactorable. A 'purely hypothetical' scenario: a numeric routine of several klocs on length, that takes in 20 parameters with 1-3 letter obscure variable names, was written 30 years ago in fortran, was f2c:d 20 years ago into c and has been doing it's 'stuff' correctly ever since somewhere in the bottom of mission critical code in a codebase of millions of lines. Commercial codebase. Only a han…

The scenario you describe is a disaster waiting to happen.

Refactor it, preferably yesterday - but make a "shadow deploy". For each set of input / output parameters run both functions and compare them. If they differ, use the old one and go back to figuring out where it went wrong. After some time you can be quite sure that the new clean function works as it should - then you just switch.

Re: Germany is turning on its monster stellarator

#105

Post by kuschku »

vidarh wrote: post #80
kuschku wrote: post #59

Earlier quoted context omitted.

Because this defeat device is nothing you should blame on a single engineer, it is clearly a systematic issue, and normal engineers should not be held accountable for actions that the CEO and board forced them to do.

On the other hand it teaches those on the ground that obeying illegal orders is perfectly fine, because, hey, you won't get punished.

It is also the only way you get people ever providing evidence against their boss, as otherwise they'd risk incriminating themselves.

Re: Germany is turning on its monster stellarator

#106

Post by dgudkov »

A naive question - if this kind of reactors start producing more energy than consuming, what kind of fuel would they need? AFAIK the Sun slowly burns hydrogen into helium. Does it mean that stellarators would only need hydrogen to operate? That would be basically free energy.

Re: Germany is turning on its monster stellarator

#107

Post by drjesusphd »

zamalek wrote: post #78
drjesusphd wrote: post #62

Earlier quoted context omitted.

Can you explain what you mean by tokamaks "going against the physics"?

So far as I understand it (arm chair physicist), Stellerators "shape" the plasma in a "natural" way, Tokamaks force it into a more "unnatural" shape - like trying to put a beach ball [plasma] into a box [torus]. If I misunderstand it disregard my comment entirely, although I'd like to know why.

Here's how I understand it:

- The simplest closed magnetic configuration is a torus. You can't smoothly "comb a hairy ball", but you can comb a hairy torus.

- For a toroidal plasma to be stable, it needs magnetic field components both the "long way" around (toroidal), and the "short way" around (poloidal).

- The tokamak generates the poloidal field from a current within the plasma, whereas the stellerator imposes that component with external magnets.

So you could make a "natural" argument either way, and I was asking the grandparent in what sense the stellerator is more "natural".

Re: Germany is turning on its monster stellarator

#108

Post by DennisP »

jlebrech wrote: post #7

I'm still waiting on LFTR.

Uranium-fueled molten salt reactors will probably happen first; they'd have the same safety advantages but without the huge extension of fuel supply that you'd get from thorium breeding. Some designs would be more proliferation-resistant than LFTRs. Startups attempting it include Terrestrial Energy, Transatomic, ThorCon, Moltex, and Seaborg.

Re: Germany is turning on its monster stellarator

#109

Post by Retra »

vidarh wrote: post #80
kuschku wrote: post #59

Earlier quoted context omitted.

Because this defeat device is nothing you should blame on a single engineer, it is clearly a systematic issue, and normal engineers should not be held accountable for actions that the CEO and board forced them to do.

On the other hand it teaches those on the ground that obeying illegal orders is perfectly fine, because, hey, you won't get punished.

Disobeying those orders would just get you quietly fired.
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