[jeltz]

I think you missed the point. If you have a 100 MW communicstion satellite and a 100 MW compute satellite those are very different beasts. The first might send 50% of the energy away as radio communication making it effectively a 50 MW satellitefor cooling purposes.

[habinero]

No, they didn't. You can't "send away" thermal energy via radio waves. At the temperatures we're talking about, thermal energy is in the infrared. That's blackbody radiation.

[adrian_b]

You missed the point.

Nobody describes a satellite by specifying the amount of heat that it produces, but by the amount of electrical energy that it consumes.

In a communication satellite, a large fraction of the consumed electrical energy goes into the radio transmitter. Radio transmitters are very efficient and most of the consumed power is emitted as radio waves and only a very small part is converted into heat, which must be handled by the cooling system.

So in any communication satellite, a significant fraction of the consumed energy does not become heat.

[mortehu]

Your answer makes it seem like you too missed the point. If a Starlink sends a 1000W signal to Earth, that is 1000W of power that does not heat the satellite.