Comment by yabones
2 days ago
Yeah, I don't see a way to get around the fact that space is a fabulous insulator. That's precisely how expensive insulated drink containers work so well.
If it was just about cooling and power availability, you'd think people would be running giant solar+compute barges in international waters, but nobody is doing that. Even the "seasteading" guys from last decade.
These proposals, if serious, are just to avoid planning permission and land ownership difficulties. If unserious, it's simply to get attention. And we're talking about it, aren't we?
You should read the linked article, they talk about it there. You radiate the heat into space which takes less surface area than the solar panels and you can just have them back to back.
In general I don't understand this line of thinking. This would be such a basic problem to miss, so my first instinct would be to just look up what solution other people propose. It is very easy to find this online.
Please have a look at how real stations like ISS handle the problem and do not trust in should-work science fiction. It's hard. https://en.wikipedia.org/wiki/International_Space_Station#Po...
Taking a system which was conceptualized about a quarter of a century ago and serves much different needs than what a datacenter in space needs (e.g. very strict thermal band, compared to acceptable temperature range from 20 to 80 degrees) isn't ideal.
The physics is quite simple and you can definitely make it work out. The Stefan Boltzman law works in your favor the higher you can push your temperatures.
If anything a orbital datacenter could be a slightly easier case. Ideally it will be in an orbit which always sees the sun. Most other satellites need to be in the earth shadow from time to time making heaters as well radiators necessary.
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It's definitely a solvable problem. But it is a major cost factor that is commonly handwaved away. It also restricts the size of each individual satellite: moving electricity through wires is much easier than pumping cooling fluid to radiators, so radiators are harder to scale. Not a big deal at ISS scale, but some proposals had square kilometers of solar arrays per satellite
That exactly. It's not that it's impossible. It's that it's heavy to efficiently transport heat to the radiators or requires a lot of tiny sats, which have their with problems.
But heat = energy, right? So maybe we don’t really want to radiate it, but redirect it back into the system in a usable way and reduce how much we need to take in? (From the sun etc)
That's not how physics works. Heat in and of itself does not contain usable energy. The only useful energy to be extracted from heat comes from the difference in temperature between two objects. You can only extract work from thermal energy by moving heat from one place to another, which can only happen by moving energy from a hot object to a cold one.
This is all fundamental to the universe. All energy in the universe comes exclusively from systems moving from a low entropy state to a higher entropy state. Energy isn't a static absolute value we can just use. It must be extracted from an energy gradient.
Useful, extractable energy comes from a temperature differential, not just temperature itself. Once your system is at temperature equilibrium, you cant extract energy anymore and must shed that temperature as heat
Enter https://en.wikipedia.org/wiki/Thermophotovoltaic_energy_conv...