upvote
> The radiators are much smaller than the solar arrays.

Modern solar panels are way more efficient than the ancient ones in ISS, at least 10x. The cooling radiators are smaller than solar panels because they are stacked and therefore effectively 5x efficient.

Unless there are at least 2x performance improvements on the cooling system, the cooling system would have to be larger than solar panels in a modern deployment.

reply
This is false. It’s pretty straightforward to prove using Stefan-Boltzmann. Radiating from both sides at 300K, a square radiator that’s 1 meter on a side emits 920W.

Additionally, you wouldn’t use cutting edge 35% triple junction cells for a space datacenter, you’d use silicon cells like Starlink and ISS use. 22% efficient with 90% full factor, given 1350W/m^2 and thus 270W/m^2, to provide enough power for that radiator you’d need a solar panel 3.4 times as big, and that’s if you were in 24/7 sunshine. If you’re in a low orbit that’s obscured almost half the time, it’s 6-7 times as big.

Why do people keep making these obviously wrong claims when a paragraph of arithmetic shows they’re wrong? Do the math.

reply