> You'd have to build a fully underground cooling system that goes to a nearby river (or huge lake) and use the cold water from that, which would get costly quick.

Helsinki gets its water from the 120 km Päijänne Water Tunnel, which cost €200-250 million (adjusted for inflation) to build. Peak flow is 10 m^3/s by gravity alone and up to 20 m^3/s with pumps, which should be enough to cool a 1 GW data center. You could increase the cost by 2x (because real wages have gone up), by another 2x (because middlemen have destroyed productivity), and by yet another 2x (because everything is more expensive in America), and it would still be pretty reasonable.

Iron Mountain does it but they used an existing limestone mine with a large water reservoir [1][2]

Edit: I guess the scale isn't comparable to a, for example, Google data center though.

[1] https://www.ironmountain.com/data-centers/colocation/our-dat...

[2] https://betterbuildingssolutioncenter.energy.gov/showcase-pr...

They already run liquid cooling loops - compute density is way beyond what could circulate through air. Adding more pipes is probably trivial on the scale of datacenter expenses

So they want to build it in space. Trade one heat problem for another, but put it completely out of range (for most attackers).

Pionen in sweden is a datacenter in a bunker. The Pirate Bay used to be hosted there.

neat. why can't you put the heat in the mountain?

Lots of people have built commercial, non-military, boutique scale stuff in hardened facilities, nobody I'm aware of has done it at scale. There's certainly money to be made from selling expensive "we put datacenter stuff deep down inside a mine" maybe to some weird enterprise and government customers, so the revenue per rack (or per theoretical 208V 30A circuit?) is probably a lot more than commodity colo. But I would very much like to see the aerial photos, if anyone can link them, to a claimed large scale underground or hardened datacenter.

It's a severe engineering challenge to hide massive heat exchangers on the scale of the datacenters built in the industrial area near Dulles (coordinate example: 38.9817915,-77.417775). Find those on a map and observe the scale of their cooling and generator systems and then try to find anything comparable that's been built underground.

It's sad that we have moved away so far from the decentralized web from the 90s and the P2P boom of the 00s. Just like solar panels on every house as a source of energy are much harder to take out than just a few power plants, local P2P storage, messaging, source management, etc. are much harder to take out.

But yeah, the economic incentives are creating unicorns and centralizing compute/capital/etc.

Ukraine are hitting targets 2,500km away

https://united24media.com/war-in-ukraine/ukraine-hits-russia...

dunno, Moscow to Novosibirsk is around 1,800 miles straight-line distance. The war would be probably over by the time Ukraine would have developed those capabilities.

Buried fiber, hard to attack. Fiber repeater shelters, easy to attack. Their locations are public information, and any non public are trivial to find, in my experience as a cybersecurity professional who seeks out infra vulnerabilities for reporting for fun. Public records, satellite imagery, all OSINT one can do from a workstation.

You could potentially bury them in the ground, assuming you don’t use a generator for backup power. To my knowledge, this is not done today except in urban areas where an underground vault is used for power and comms.

https://www.decommsystems.com/resources/what-goes-into-an-il...

Russia is hitting everything in Ukraine… DC, power plants, rail, road housing

Ukraine has a very targeted response but notably tries to minimise civilian casualties

> For 200 kW, you would need a system 12.5 times larger, about 531 square meters—2.6 times larger than the solar array. The satellite would be enormous, larger than the ISS, and all of that for only three racks.

Starlink gen 3 satellite is designed to dissipate 250 kW. You are talking about an already solved issue, with real hardware already being built today.

Are you asserting that we must use the exact same heat rejection architecture the ISS uses for data centers?

https://en.wikipedia.org/wiki/Liquid_droplet_radiator

> Space is a near-vacuum, so it's hard to get rid of the heat.

It's not that hard, Starlink constellation already dissipates around 100 MW of heat, split over many satellites. Any orbital datacenter would use similarly distributed satellites.