[skywhopper]

The idea that we can’t get enough electrical power on earth because of supply constraints, but that we can solve that by launching the datacenters and their entire support infrastructure into space makes no sense unless you’re a huckster trying to pump up your space launch business ahead of an IPO. There’s no way we are more constrained on land-based solar+battery equipment than we would be on space-worthy solar+battery+space-cooling equipment plus sufficient launch infrastructure and resources. Meanwhile, our government is paying companies to stop building wind power and bombing sources of natural gas.

[chasd00]

sheesh i didn't say a datacenter-in-space was a good/feasibnle idea. The point i was making is I feel that building power plants to power a datacenter is turning out to be harder than software people realize and multi-year (or worse) delays likely the result.

[wmf]

For whatever reason, nobody is trying to build solar-powered AI datacenters. Maybe they can't find enough land.

[fckgw]

The space required to install enough solar panels, especially in the places these things are going (like Ohio, where it's NOT ideal for solar generation), would far, far outsize the data center itself by a significant magnitude.

[quickthrowman]

It takes 2.5 million solar panels to generate 1GW of electricity assuming 400W per panel and direct sunlight. 2.5M times 18 sq ft per panel is about 1000 acres or ~1.55 sq mi.

That would work for a 1 GW data center, during the day, without clouds, during the summer.

[0cf8612b2e1e]

Is that supposed to be a lot? The US is some 3.8 million square miles.

A decade old Reddit thread estimated there are 60 square miles of just McDonalds. That is, a McDonalds footprint of solar panels alone is 39GW.

https://www.reddit.com/r/theydidthemath/comments/2bq7l2/so_i...

[downrightmike]

The US gov't owns at least 50% of every state in the west. Or they could just build in the middle of bum f*ck Texas and get fossil and renewables. Too bad Texas' grid is so piss poor

[AnthonyMouse]

The Texas grid that already generates more TWh from renewables than any other state?

[treis]

Half the time you get 0 solar power.

[AnthonyMouse]

If only data centers had some kind of backup systems to prevent power interruptions, like inverters with batteries attached to them. They could call it an Uninterruptible Power Supply and then charge the batteries when other power is available and run on them when it isn't.

[treis]

Not nearly big enough for data centers approaching 1 GW. Largest is 3 GWH which gets you 3ish hours.

Theoretically you can put as many batteries together but it'd be enormously expensive and run into the same supply chain issues.

[AnthonyMouse]

Anything using 1GW of power is going to be "enormously expensive". The all-in cost of a 1GW data center is on the order of $50 billion. A billion dollars in storage batteries is ~2% of the cost, which is completely reasonable.

~1600 GWh of lithium batteries are produced each year and hundreds of GWh/year of production capacity have been added in each of the last few years, so ~12 GWh isn't going to upend the market.

[wmf]

UPSes are designed to run for minutes not hours. I guess enough Megapacks to run overnight would be more expensive than gas generators.

[AnthonyMouse]

If grid storage batteries are economical in the general case then why wouldn't they be doubly so in a place where the inverters are a sunk cost and you're saving the transmission costs because the load is at the same site as the batteries?

The competition isn't the cost of generators, it's the cost of grid power, or the cost of operating gas generators every day.

[treis]

They aren't economical in the general sense. They are economical to provide frequency stabilization, grid efficiency, and maybe a few hours of demand shifting. They're not yet economical to store solar power during the day and discharge it at night. We are getting closer but I don't think we are quite yet there.

[ww520]

Space DC make sense when local governments and communities don't want DC built on Earth. Space DC is an engineering and finance problem, not a problem in legal/permission, real estate, power generation, grid delivery, environmental, etc.

[gtowey]

You think that building out space infrastructure is a less hard problem to solve than bribing a few local governments to get some building permits?

[panny]

>a less hard problem to solve than bribing a few local governments

Wouldn't it be best if the data centers were just... good neighbors? Like everyone talking about illegal bribes and impossible moonshots when the answer is just don't suck?

[fhdkweig]

We are well past the point of these companies caring about their reputations. People are already losing their homes over this. Here is Penguinz0's commentary on a news report of GA Power eminent domaining someone's home to run a power line through it to power a data center.

https://www.youtube.com/watch?v=bySJ-oVGtvs

[AnthonyMouse]

The general problem is that we've made construction suck for a while now and people are suddenly paying attention to it but only in the case of data centers.

You don't get caught paying bribes if government officials aren't accepting bribes. The problem is the governments have been operating in a mode where blocking everything is the default and paying bribes is the expected way for things to get approved.

[lightbritefight]

The issue with this is that datacenters are inherent "suck" machines. It takes a lot more effort and cost for them to not suck then for them to suck, so "sucking" is part of their core design.

Up till recently, they were a rare enough object that distressed communities still saw the glitz and glam that they are sold with as valuable. Now that brutalist assholes are trying to jam them in every nook and cranny of the earth, word is getting out and people aren't buying it anymore.

There have been some attempts to try floating or water immersed data centers that mitigate or at least hide some of their suckiness, but these were hard and costly, so the incentives weren't there to do them anyway. Maybe now those ideas will resurface and improve, but I expect "bribe, con or sue rural community to destroy their quality of life" is still cheaper and easier.

[ww520]

You missed the lawsuits by everyone else.

[jonlucc]

Isn't it still far simpler and cheaper to build and maintain a DC in the most rural parts of North America than to launch it to space?

[ww520]

You still need to build the power infrastructure to the rural areas. Build the infrastructure for the people, like roads, sewage, water, buildings, etc. Navigate the regulation and permit processes.

[mike_hearn]

On Earth it has to be fossil fuels. With solar you can't do it. I haven't done the calculations myself so, full disclosure, AI work ahead. But I asked GPT 5.6 how big a solar and battery farm would have to be to power a one gigawatt datacenter such that it could ride out a few cloudy days in a row (this is far below the reliability bar).

Its answer is you'd need an "absurdly large battery" and a solar farm of over 100 square kilometers, quite possibly up to over 200 square kilometers. And it would need to be built in the desert.

Also, normal utility scale LiON battery sites are only meant to provide stabilization services for hours, not days.

The problem is you have to overspec the solar farm quite a lot because it must not only be able to power a one gigawatt facility, but also generate more than that so it can recharge the battery packs during the day too.

So this just doesn't work. You think datacenter permitting is bad when it only requires some on-site gas turbines? Imagine the difficulty of getting a 200 square kilometer solar farm over the finishing line.

No, it's quite possible Elon is going to win this one. Regulation is expensive! He can just fire a constant stream of satellites into space. The constellation needed to provide a gigawatt of inferencing would be about the same size as today's Starlink system, well within the bounds of what he's proven can be done.

The threat to space based datacenters isn't really the physics of it. It's the risk of a bubble pop that temporarily craters demand and/or an overbuild of terrestrial capacity. Outside of the software industry we don't see huge new blocks of inferencing demand, and OpenAI at least doesn't seem capacity constrained at all right now.

[bronson]

Why restrict yourself to 100% solar? Solar augmented by grid is pretty great.

Also, you very conspicuously avoided talking about the difficulty/impact of a 1GW datacenter in space. One might suspect your motives aren't as impartial as you seem to think.

[mike_hearn]

The whole problem is difficulty getting grid connections on Earth. If you can just hook up to the grid then why not just use it for everything.

I don't have any motives, what are you talking about? I don't own SpaceX stock if that's what you're thinking.

What's the difficulty of a 1GW datacenter in space? The number of satellites it requires seems to be within the realm of what SpaceX has already achieved. If the calculations are wrong, by all means say so, I haven't checked them.

[rented_mule]

> What's the difficulty of a 1GW datacenter in space?

Simple back of the envelope calculations?

Let's assume your numbers are correct and that panels in space can generate 10x the power per square meter per 24 hour period (due to efficiency, lack of night, and lack of atmosphere/weather). That means 10 KM^2 are needed for one such data center. The largest we've built in space is ~3,000 M^2 on the ISS. So one of these DCs in space will require an array ~3,000 times the size of the largest we've built before. Or, it's going to require ~3,000 satellites, each with an array the size of the largest we've ever deployed.

The largest Starlink satellites currently deployed generate less than 30 KW each. We'd need more than 30,000 of those to generate this much power. Starlink has launched ~12,500 to date, with ~10,000 still functioning. So 3x the size of the functioning fleet that's taken 8+ years to deploy. Currently, we are deploying well under 5,000 per year. Let's assume we can come up with enough spare capacity to launch 5,000 per year. That's 6 years to deploy the first 1GW DC. By the time we get to 1GW, the average GPU is 3 years old. So we need to continue to deploy 5,000 satellites per year to maintain 1GW of GPUs that are, on average, 3 years behind current generation GPU designs.

This is all before we get to the economics of launching, the cost of the satellites themselves, heat dissipation, radiation hardening, hardware failure rates (~20% of deployed Starlink satellites are no longer functioning), etc.

[mike_hearn]

The whole thing does assume Starship works, so at that point satellites could be launched much faster.

I assume Starmind would use Tesla designed chips, which removes Nvidia's margin and so the cost of the chips is not necessarily so high.

Rad hardening isn't important at low altitudes, and inferencing can smoothly recover from glitched calculations/lockups.

I don't know if it makes economic sense or ever will, but technologically it does seem possible. And if you can't build on Earth for political reasons, then space can win by default.

[rented_mule]

In terms of what we decide to build, impossible vs. impractical is not a particularly interesting distinction (that distinction can give rise to fun science fiction). Practicality is at the core of good engineering, and possibility is just the first of many steps in evaluating practicality.

If we're going with a distributed approach, there are other ideas that are more practical. For example, send 1 KW boxes to a million people (< 1% of American homes, but there's no reason to limit this to the US). Very roughly, these are beefed-up gaming consoles - you could even start with existing gaming consoles. That box plugs into electricity and ethernet. Pay each of those people $1,000 a month to leave their box running 24/7. For people with a lot of solar at home, it could be a nice income stream. At $1B per year for payouts, it's far cheaper than doing it in orbit. And it doesn't rely on promised but as-yet undelivered technologies. But data centers are probably more practical.

[AnthonyMouse]

> The whole problem is difficulty getting grid connections on Earth. If you can just hook up to the grid then why not just use it for everything.

Because you already need inverters and batteries for backup power and then using solar + batteries for ordinary operations and the grid for backup is cheaper than the other way around.

Which is also why you may not even need the grid connection. Suppose you have diesel generators to use in case you have some kind of a fault in the solar system, the same as was traditionally done in case of a failure of a grid connection, and then use those for the one week every two years when solar generation is too low.

[bronson]

> What's the difficulty of a 1GW datacenter in space?

Why don't you ask your AI, the way you did with your earth-based scenario?

[abirch]

How do you cool the data center in space cost effectively? Unfortunately in space there isn't a lot of material (air) to transfer the heat.

[mike_hearn]

You can just use ordinary radiators. Do the calculations, cooling isn't the problem it's made out to be.

[abirch]

It's the size of the radiators and the expense of getting them up into orbit (along with maintenance)

Most of my assumptions come from discussions like: https://news.ycombinator.com/item?id=46876105

[sokka_h2otribe]

(1) these are not ordinary radiators because ordinary radiators aren't gold plated and don't unfold dramatically from compact shipping sizes (2) It's absolutely loads of radiators

[bryanlarsen]

100 square kilometers sounds like a big area. And it is, in continental Europe or in an urban area. In Montana, it's enough space for a few hundred cows. In desert regions, it's worth even less. You can buy 100 square kilometres of unserviced desert land for ~$10M.

[mgerdts]

Even better, get rid of the mandate for ethanol and cover a portion of the ex corn fields with solar panels with native plants under and around them. A small portion of the land that is near existing transmission lines is needed to replace combustion vehicles with electric vehicles. The bulk of the rest of this land could be available for other uses, including data centers.

This gives: sustained income for landowners, CO2 reduction, power for new uses, and partially restored ecosystems that have been greatly harmed by chemical laden monocultures.