[vlovich123]

The maximum heat rejection capacity of the ISS is 126Kw.

Musk’s proposal is to put 1 rack per satellite drawing 150kw using 110 m^2 of radiators (1/4th that of the ISS). The only way to do that is by running the satellite at 71-100C which is a problem for the chips to actually run.

So the open questions are: * can they actually dump the heat and can they have the racks running so hot for so long * is it economical to in one year replace all the capacity you launched 5 years ago (you save up to 0.5B in electricity costs over that time frame but that doesn’t seem like a lot for having to replace that much capacity buildup)? And given they’re running racks way hotter than has been validated on earth, will those chips end up lasting 5 years (including space radiation).

Pretending like it’s a solved problem is neat but I’m not saying sure it’ll be so easy.

[roryirvine]

Those temperatures aren't necessarily a problem for the chips (there are some minor design changes needed, so it's more a question of having enough volume to justify doing it). The real issue is that this is yet another thing you could do better on earth.

In other words, run fully lights-out datacentres that no humans will access during normal operation - this allows you create more extreme temperature gradients and to replace the atmosphere with CO2 (or even He2), both of which will make your cooling solution much more efficient as well as increasing rack density and perhaps even taking the place of a fire suppression system.

The reason that no-one's actually doing that at scale is that it's currently significantly more expensive than traditional datacentre designs. And yet, that's still much less expensive than boosting racks into space and then letting them burn up in the atmosphere five years later.

[phs318u]

It’s as solved as FSD.

[krcz]

Wouldn't it be possible to use heat pumps, making radiators 100C or hotter while running GPUs much below that?

[Eddy_Viscosity2]

That's how space heat radiators already work. Which, by the way, add significant costs to both energy and weight for space-based data center. The problem is once you 'pump' the heat out is what happens next. With out conductive or convective heat transfer, all that is left is radiation of that heat. Which is the slow.