Yes but if the solar panel area scales linearly with radiator area, the problem doesn't get worse?

It does if you don't turn off the heat source every 30 minutes or so. Since the "datacenters" are targeted at sun synchronous orbits they have 24/7 heat issues. And they convert pretty much all collected energy into heat as well (and some data, but that's negligible). Those GPUs are not magically not generating heat.

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manquer 5 hours ago | parent | prev | next [-]

Wouldn't the panels themselves need cooling too? The ones on earth generate heat while being in the sun.

There are commercial systems that can use open loop cooling (i.e. spray water) to improve efficiency of the panel by keeping the panel at a optimal temp of ~25C and the more expensive closed loop systems with active cooling recovers additional energy from the heat by circulating water like a solar heater in the panel back.

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cowsandmilk 5 hours ago | parent | prev [-]

I would hope SpaceX is using more efficient solar cells than the ISS

	▲	philipkglass 5 hours ago \| parent [-]
		Probably not. The ISS got a solar array upgrade after its initial launch: https://www.spectrolab.com/company.html Twenty-five years after the ISS began operations in low Earth orbit, a new generation of advanced solar cells from Spectrolab, twice as efficient as their predecessors, are supplementing the existing arrays to allow the ISS to continue to operate to 2030 and beyond. Eight new arrays, known as iROSAs (ISS Roll-Out Solar Arrays) are being installed on the ISS in orbit. The new arrays use multi-junction compound semiconductor solar cells from Spectrolab. These cells cost something like 500 times as much per watt as modern silicon solar cells, and they only produce about 50% more power per unit area. On top of that, the materials that Spectrolab cells are made of are inherently rare. Anyone talking about scaling solar to terawatts has to rely on silicon or maybe perovskite materials (but those are still experimental).