GoKawiilCooling in space
Posted 2026-06-11
With all the talk of data centers in space, I remember my first question being “isn’t cooling this stuff a fundamental limit on whether we can have orbital data centers at all?” Turns out that at least this part is definitely doable and quite possible.
I’d like to give a quick thanks to Saurav for convincing me of this originally and Parth for discussions/encouraging me to write this.
I’ll go a little bit slow on this one, since my guess is readers who are interested in this particular topic probably need a little more background. If you don’t, you can skim this next subsection and head directly to the next one.
Why do we need cooling?
Ok, assume we have a datacenter in space and all of its electrical energy comes from solar cells, pointed at the sun.
In this orbital data center (which, in my head, I picture as a big box with solar panels sticking out of it, facing directly at the sun) we have a bunch of GPUs. It’s possible we also have some communication equipment (to send data up to and down from the satellite) and maybe some basic power equipment, but assume that ~ all of the power goes to the GPUs.1
A GPU, in short, is a machine that takes in electricity and outputs heat (and, as a side effect, performs some hopefully-useful computation). In fact, essentially all of the electricity input is converted to heat, which, if not dumped somewhere, will eventually cause the GPU to melt and become a very expensive paperweight made of copper and silicon.
In other words, we need some way of dumping the heat out of the GPU, ideally to some large reservoir.
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