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At 70-80C (working temp of silicon chips) 1m2 radiates 700-800W, i.e. the heat of 1 GPU like H200 without any need for any cooling equipment beside the radiator itself( and may be some dumb heatpiping) . To acquire that energy you'd need 3-4m2 of solar panels. So a datacenter would be a large field of solar panels with a smaller field of heat radiators in their shadow.

To the commenter below: yes, exactly, this is where my thinking on that started at the cryptocurrency boom - https://news.ycombinator.com/item?id=26289423 - as you don't need close connection between mining GPUs. For AI you'd need to cluster several together while still overall scheme is the same.

>what the equilibrium temperature of a black planar surface is at a given distance from the sun.

it is 120C at the Earth orbit. So you do need to have some reflection, either back through the solar panels, or the radiators to have a reflective back toward the solar panels in the shadow of which they are to be located.

by fc417fc80226 days ago|

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You can probably (I haven't verified this) omit separate radiators and just use the back of the solar panels. Effectively you're describing mounting each H200 to the back of a 4 m^2 solar array at which point I suspect the equilibrium temperature will fall within an acceptable range. In fact the H200 and electricity are both entirely irrelevant here - the core question is what the equilibrium temperature of a black planar surface is at a given distance from the sun.

by kreelman26 days ago|

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Would it be feasible to put several JWST-like stirling engines somewhere in the mix to use up some of that heat and turn it into some kind of useful energy? ....

Perhaps running pumps that move around coolant passing over the cubes of GPUs? ..

That would be extra weight/cost into orbit though...

Also, don't solar panels have reduced efficiency when they're hot? And having anything hot surely increases failure rates.. with metals getting closer to melting points...?

by fc417fc80226 days ago|

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We should be well below the boiling point of water here, not anywhere near the melting point of metal. Any panel efficiency gain needs to be balanced against the energy required to cool the panels, the added mechanical complexity, the added material expense, and the added weight to orbit.

Ideally this is a static structure with an equilibrium temperature acceptable for the silicone to operate. If the required panel area is too hot on its own then a perpendicular cooling fin on the back that falls entirely within the shadow is added.