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Data centers in space makes no sense

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Re: Data centers in space makes no sense

#351
post #288

Earlier quoted context omitted.

Write some books with good ideas then so future human-robots will be inspired to make your dreams into reality.

Unfortunately, these guys are only excited about building the Torment Nexus.

"It's only Torment™ if you aren't a double-digit shareholder!"

Re: Data centers in space makes no sense

#352
post #262

Earlier quoted context omitted.

Can’t you heat exchange inside the satellite, and make one part of the satellite incredibly hot so that it radiates a lot and dissipates. This is just a question. I have no expertise at all with this.

yes. it is how sats currently handle this. its actually exponentially effective too P = E S A T^4 requires a lot of weight (cooling fluid). requires a lot of materials science (dont want to burn out radiator). requires a lot of moving parts (sun shutters if your orbit ever faces the sun - radiator is going to be both ways). so that sounds all well and good (wow! 4th power efficiency!) but it's still insanely expensiv…

Be careful with the math there. While a 4th power is awesome you got the Stefan-Boltzman constant to consider and that's on the order of 10^-8

Radiative power is really efficient for hot things but not so great when you're trying to keep things down to normal levels. Efficient for shedding heat from a sun but not so much for keeping a cpu from overheating...

Re: Data centers in space makes no sense

#353
I was talking to someone about this the other day. I was part of a team at NASA that developed a cooling system for the ISS and this whole premise makes no sense to me.

1. Getting things to space is incredibly expensive

2. Ingress/egress are almost always a major bottleneck - how is bandwidth cheaper in space?

3. Chips must be “Rad-hard” - that is do more error correcting from ionizing radiation - there were entire teams at NASA dedicated to special hardware for this.

4. Gravity and atmospheric pressure actually do wonders for easy cooling. Heat is not dissipated in space like we are all used to and you must burn additional energy trying to move the heat generated away from source.

5. Energy production will be cheaper from earth due to mass manufacturing of necessary components in energy systems - space energy systems need novel technology where economies of scale are lost.

Would love for someone to make the case for why it actually makes total sense, because it’s really hard to see for me!

Re: Data centers in space makes no sense

#354
post #115

I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…

The equation has a ^4 to the temperature. If you raise the temperature of your radiator by ~50 degrees you double its emission capacity. This is well within the range of specialised phase change compressors, aka fancy air conditioning pumps. Next up in the equation is surface emissivity which we’ve got a lot of experience in the automotive sector. And finally surface area, once again, getting quite good here with nan…

Even if you create a material with surface emissivity of 1.0:

- let's say 8x 800W GPUs and neglect the CPU, that's 6400W

- let's further assume the PSU is 100% efficient

- let's also assume that you allow the server hardware to run at 77 degrees C, or 350K, which is already pretty hot for modern datacenter chips.

Your radiator would need to dissipate those 6400W, requiring it to be almost 8 square meters in size. That's a lot of launch mass. Adding 50 degrees will reduce your required area to only about 4.4 square meters with the consequence that chip temps will rise by 50 degrees also, putting them at 127 degrees C.

No CPU I'm aware of can run at those temps for very long and most modern chips will start to self throttle above about 100

Re: Data centers in space makes no sense

#355
post #115

I would not assume cooling has been worked out. Space is a vacuum. i.e. The lack-of-a-thing that makes a thermos great at keeping your drink hot. A satellite is, if nothing else, a fantastic thermos. A data center in space would necessarily rely completely on cooling by radiation, unlike a terrestrial data center that can make use of convection and conduction. You can't just pipe heat out into the atmosphere or build…

musk is always up to something but remarkably people still eat this stuff up - remarkable to watch!

Re: Data centers in space makes no sense

#356
post #345

Earlier quoted context omitted.

It’s a distraction as they suck out as much value from Tesla as possible before the music stops and they go bust. There are a few really big IPOs this year including SpaceX, which will likely trigger significant market volatility.

yes, tesla, famously the worst performing car manufacturer with the worst profit margins, is definitely going bust any day now

Clearly 200 forward P/E and three consecutive quarters of missed earning is a sign of profitability.

It's a stock worth $50-60 with generous valuation. The premium is the Elon bullshit and grift. That isn't gonna last forever.

Re: Data centers in space makes no sense

#357

Google, Spacex, several startups are all doing this. The best people in their fields think it might be viable. I'm skeptical as well, but you do wonder if maybe they are right and how exciting that would be.

Everyone else is announcing initiatives to investigate the feasibility of this because earthlings currently hate the data center build out. The news is full of anti-DC stories about how much electricity/water they're using. They're selling a story.

Re: Data centers in space makes no sense

#358
post #338

Earlier quoted context omitted.

It's like this. Everything about operating a datacenter in space is more difficult than it is to operate one on earth. 1. The capital costs are higher, you have to expend tons of energy to put it into orbit 2. The maintenance costs are higher because the lifetime of satellites is pretty low 3. Refurbishment is next to impossible 4. Networking is harder, either you are ok with a relatively small datacenter or you have…

>1. The capital costs are higher, you have to expend tons of energy to put it into orbit putting 1KW of solar on land - $2K, putting it into orbit on Starship (current ground-based heavy solar panels, 40kg for 4m2 of 1KW in space) - anywhere between $400 and $4K. Add to that that the costs on Earth will only be growing, while costs in space will be falling. Ultimately Starship's costs will come down to the bare cost…

> will come down to the bare cost of fuel + oxidizer

And maintenance and replacing parts and managing flights and ... You're trying to yadda-yadda so much opex here!

Re: Data centers in space makes no sense

#359

Remember what the Luddites actually did? They sabotaged the machines that were disrupting their livelihoods. If AI is as disruptive to large numbers of workers as some people think it will be, keep in mind it's a lot easier to destroy a GPU that's stored on earth than one in space. Anyone planning expenditures as large as a modern data center thinks about all kinds of risks (earthquakes, climate, power, etc), and so…

The luddites won't need to sabotage a space based GPU. They can just wait for waste heat, radiation, or a good old solar storm to do it for them. The rest of the ground lauch infrastructure is fragile.

Re: Data centers in space makes no sense

#360

Earlier quoted context omitted.

Its very simple, xAI needs money to win the AI race, so best option is to attach to Elon’s moneybank (spacex) to get cash without dilution

> xAI needs money to win the AI race Off on a tangent here but I'd love for anyone to seriously explain how they believe the "AI race" is economically winnable in any meaningful way. Like what is the believed inflection point that changes us from the current situation (where all of the state-of-the-art models are roughly equal if you squint, and the open models are only like one release cycle behind) to one where som…

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