Starcloud
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Nvidia's blog post about Starcloud's plans to build a 5-gigawatt orbital data center is met with widespread skepticism and criticism on HN, with commenters questioning the feasibility, energy efficiency, and environmental impact of the project.
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Moreover, why are the energy cost 10x lower when in space you have unlimited access to sun power? Is it the cost of building the energy production infrastructure ?
It's not a slam-dunk "no", we are seeing developments on all metrics. It's just that right now, I wouldn't be surprised if the claim of x10 improvement was anywhere from correct to x100 over-optimistic.
I'm surprised nvidia put their name on this.
More discussion: https://news.ycombinator.com/item?id=43977188
Wonder if that would be less impactful than how ever many rockets they'll need to send up, plus you could, ya know, ~drive~ bike to a failed machine.
So, it's the solar/cooling panels that make up that space, not the data centre per se.
1) The atmosphere attenuates sunlight (even when it's not cloudy)
2) The solar array in orbit can pivot to face the sun all the time.
3) While most orbits will go into earth's shadow some of the time, on average they'll be in sunlight more of the time than a typical point on the surface.
see https://en.wikipedia.org/wiki/Solar_irradiance
Even the ISS has sizable radiators. The Shuttle had deployable radiators in the form of the bay doors if my memory serves me correctly.
Oddly enough the otherwise dumb Avatar films are among the only ones to show starships with something approaching proper radiators.
There’s no air resistance in space so radiators don’t impact your flight characteristics.
I'm pretty sure it was that series that also described https://en.wikipedia.org/wiki/Liquid_droplet_radiator , with the side effects of different ships having very distinct heat patterns because of their radiator patterns. And that if a ship ever had to make a turn while they were active, big glowing arcs of slowly-cooling droplets would be flung out into space and leave a kind of heat plume.
> Next [after loading the computers with on-orbit software] we opened the payload bay doors. The inside of those doors contained radiators used to dump the heat generated by our electronics into space. If they failed to open, we’d have only a couple hours to get Discovery back on Earth before she fried her brains. But both doors swung open as planned, another milestone passed.
I imagine it's the same reason James Cameron is a world expert on submersibles - the guy picks individual topics in his movies to really get right.
> Because caches hold the most recent and most relevant data to the current processing, it is critical that this data be accurate. To enable this, AMD has designed EPYC with multiple tiers of cache protection. The level 1 data cache includes SEC-DED ECC, which can detect two-bit errors and correct single-bit errors. Through parity and retry, L1 data cache tag errors and L1 instruction cache errors are automatically corrected. The L2 and L3 caches are extended even further with the ability to correct double errors and detect triple errors.
If it not i want dibs on it.
> and even the nuclear decay (due to practical considerations the latter, as well as the atmospheric noise, is not viable except for fairly restricted applications or online distribution services)
Here on earth we are surrounded by many molecules, that are not so cold, but colder than us and together they can take a lot of our excess heat energy away.
Stuff in space does.
This prompted my curiosity. None of the following contradicts the thrust of your message, but I thought the nuance is interesting to share.
Interstellar space isn't a vacuum. Space is mostly empty compared to Earthly standards, but it still contains gas (mostly hydrogen and helium), dust, radiation, magnetic fields, and quantum activity.
The emptiest regions are incredibly sparse, but not completely empty. Even in a perfect vacuum, quantum mechanics predicst that particle-antiparticle pairs constantly pop in and out of existence, so empty space can be said to be buzzing with tiny fluctuations.
> Space is not cold. It has no real value for temperature. Stuff in space does.
The cosmic microwave background radiation, the left-over energy from the Big Bang, sets a baseline temperature of about 2.7K (-270°C), just above absolute zero.
Temperature depends on particle collisions, and since space isn't a vacuum, just incredibly sparse, one can talk about the temperature of space, but you're right that what is typically more relevant is the temperature of "specific" objects.
For solar panels:
Assuming area of 1000 square meters (30m x 30m square), solar irradiance of 1 kW/m^2, efficiency of 0.2. As a result power is 200 kW.
For radiators:
Stefan-Boltzmann constant 6E-8, temperature difference of 300 K, emissivity of one, we get total radiator power 1000 x 6E-8 x 300^4 = 486 kW.
The radiator number is bigger so the radiator could be smaller than the solar panels and could still radiate away all the heat. With caveats.
Temperature difference in the radiator is the biggest open question, and the design is very sensitive to that. Say if your chips run at 70 C (340 K), what is the cool temperature needed to cool down to, what is the assumed solar and earth flux hitting the radiator, depends on geometry and so on. And then in reality part of the radiator is cooler and radiates way less, so most of the energy is radiated from the hot part. How low do you need to get the cool end temperature to, in order to not fry your chips? I guess you could run at very high flow rates and small temperature deltas to minimize radiator size but then rest of the system becomes heavier.
If you think of a big ball of droplet mist. From the point of view of a droplet in the center, it gets heat radiation from all the droplets around it. It can only radiate heat to black sky it sees, and it might be none, it's "sky" is just filled by other hot droplets. So it doesn't cool at all.
The total power radiated can't exceed the proportion to the macro surface area with tricks.
I'm skeptical that it makes any economic sense to put a datacenter in orbit, but the focus on the radiators in the last discussion was odd - if you can make the power generation work, you can make the heat dissipation work.
Any data center that isn't generating massive heat is a waste of our time.
And no, JWST is not doing industrial scale cooling.
I could be wrong and this will be a slam dunk. To me, however, the costs/complexity (Cooling, SRP perturbation, stationkeeping, rendezvous, etc.) far outweigh the benefits of the Cheap as Free (tm) solar power
The difference between a criminal and a law-abiding citizen isn't that the citizen knows that crimes are wrong, it's that the citizen cares that crimes are wrong and the criminal doesn't.
Nope, probably the more apt description is 'in denial'.
I'd describe it as "kayfabe".
https://starcloudinc.github.io/wp.pdf
Your thinking seems more risk averse, which is similar to myself. However that doesn't mean that without the business drivers these types of things can't happen if enough attention is given too it. Costs are often because we're comparing one thing which has significant efficiencies built into the supply chain, vs something that doesn't, which by virtue drives up the cost. Perhaps Nvidia have money to burn on trying something.
Why is this exclusive to space? If you're powering datacenters on solar, one would think covering the Sahara or other large desert in datacenters would be easier than launching them into space. Renewable energy is just as plentiful and free there, you can connect it to the rest of the world with multiple TB/s of fiber links, and the construction/maintainence costs would be a few orders of magnitude less.
These plans are so much larger than anything built so far that they're scifi.
They’re the same sort as the cold fusion people coming out of the woodwork with “investment opportunities” during the peak of ZIRP.
The first thing to consider is that this thing won’t be stationary!
Geosynchronous orbit is much more expensive to reach per kg launched, even for Starship… when it starts working properly.
Lower orbits… aren’t stationary. Who wants a data centre that’s “over the horizon” from the owning country most of the time!?
If you think AWS egress costs are bad? Just add some zeroes! No, more zeroes than that…
Would probably need to negotiate for a huge amount of dedicated priority bandwidth, but latency shouldn't actually be that bad.
* while there could, in principle, be no extra infra in the last 200 km vertically, that means someone on the ground is talking directly to GEO. As per similar discussion about big PV space stations beaming power to the ground, your minimum ground spot size for a transmitter this big and this far away is still tens of km, which limits the other parts of your overall system design.
Fine for some applications, but a massive regression from modern fiber infrastructure and definitely not suitable for everything (just think how slow the modern web is even with 15ms connections to datacenters). There's a reason why Starlink & co are trying to set up communication satellites closer to the ground.
Of all the things insane about this proposal, I'm not very bothered about this one. It could be high availability and distributed by default. Like having redundant datacenters with eventual consistency on all continents. Except the continents are spinning really fast above you...
The animation is wild... 5GW concentrated up there at the top of a field of solar panels - it's not a Starcloud, it's an electric Starfurnace.
You pretty much have to have multiple redundancy and special space-rated HW, which I wouldn't be surprised is stuck at super old process nodes to mitigate this exact same issue.
I believe it's on the order of magnitude of 100x return (for a low-orbit space photovoltiac panel that's (almost) always facing direct sun).
That is...very, very large.
The sun will be eclipsed by earth many times per day, requiring you to either shift all workloads or add substantial UPS weight. The radiator grid you need to cool 125kw is something like 16x the size of the entire data center.
I watched this video last week that went into 3 different scenarios, it's a good watch.
https://www.youtube.com/watch?v=JAcR7kqOb3o
By the way, the same channel also has a sobering video on commercial space stations. https://youtube.com/watch?v=2G60Y3ydtqY
Depends on the orbit.
https://en.wikipedia.org/wiki/Beta_angle
My understanding was that water-demands on Earth were an overblown issue and minuscule when compared to other uses of fresh water such as watering one acre of farmland.
Not to mention, "used" water is just "warm" water that can then be used again for other purposes.
So are they perpetuating a myth here? Or is water use a bigger issue than I thought?
Also, the "warm" water has already destroyed ecosystems because the data centers are just dumping it. It's a completely solvable issue if we had any common sense regulations.
Heat is almost impossible to dissipate in space because there's negligible matter to take the heat away.
In the example of a data centre, there would be considerably more heat generation than 3 astronauts, but, I would like to understand more. 38F is cold, so heat is clearly lost not as slowly as we might think.
Can I bet on the contrary odds? Could throw down my whole retirement with confidence
Think: "AI will replace all software developers in 6 months"
The famously heat conductive vacuum...
Someone fedex a vacuum flask full of hot coffee to nvidia HQ with an explanatory note.
1) Space debris. This is proposal is several orders of magnitude larger than the biggest things in near-Earth orbits. Thus equally many orders more likely to be hit by, and create, space debris
2) Heat transport - this isn't my home turf, but I can't imagine building something lightweight enough to be launched, yet also capable of transferring enough heat away from the 5 GW core, without it melting/breaking
It's been a while since I read their whitepaper, but I don't recall either of those points being addressed.
Space is just unfathomably large. If you aren’t in the same orbital plane, you’re just not going to have a problem. And if you did, Kessler syndrome in LEO is a non problem.
Could be an issue for specific orbital planes in stable orbits, but even there, it’s overblown.
I would guess in a system where coolant is pumped and the added heat of that you'll have a similar problem. This is probably further exacerbated by the fact that you cant do clever things to increase surface area - your radiating surfaces must all "see" the black of space in order to function.
Solar energy available around the clock allows it to be self-sufficient for a long time.
I suppose there will be some demand for high-security, high-price setups like that.
Censoring data in a datacenter in space requires either administrative access, or physical access. The latter is complicated in space, The former depends on your trust to the operator, and your security posture.
The difference between the US government censoring a datacentre in orbit and one in California is a matter of cost rather than practicality, and it's actually easier for other spacefaring powers to interfere with it in a deniable manner if it's that important to them than the datacentre in California
Or they are not geostationary but it also means the datacenter will connect to a different earth base station which means the data access route would change and latency would increase which would be unacceptable for a lot of use cases.
You would then need to replicate and synchronise customer data across the different space data centres to make it possible to access said data in constant and low-latency time.
Now we have one - venture capital.
Energy went into mining, extracting, refining, transporting all the raw materials needed to make these chips.
This is typical tech industry green washing as the industry fails to accept its destructive influence on the planet.
We need practical solutions that help reduce consumption and waste and actually address the issues. We don’t always need more we need to find a way to use less.
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