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Comment by robertjpayne

7 hours ago

Problem wont be energy input it'll be heat dumping. You can't transfer heat in a vacuum effectively -- just go google how large the International Space Station's radiators are just to ensure its electrical systems are cooled adequately.

Unless someone figures out how to break the laws of thermodynamics there's never going to be a cost effective DC in space.

To keep everything under 100C (or 50C), your radiator surface area is in the same ballpark as your solar panel surface area. No laws of thermodynamics need to be broken. But you do need very low launch costs.

Edit: https://en.wikipedia.org/wiki/Planetary_equilibrium_temperat... A blackbody sphere near Earth's orbit balances out to almost exactly 0C. A sphere has about 4x as much radiating surface as capturing surface. A flat surface facing the sun that would have 2x, front and back.

ISS needs its radiators for the humans rather than for the electronics, which can run hotter than we can remain alive. However, main thing is compare them to the size of the ISS's solar panels: both are big, but similarly big.