Re: Starship
In low-earth orbit where the solar radiation flux is around 1350 Watts per square meter, and the temperature around 130 deg.C the space shuttle must have its payload bay doors open to help radiate heat. But spacecraft in higher orbits that pass through the shadow of the earth for longer time periods require batteries to keep warm. Spacecraft sent to the outer planets all use nuclear power since solar energy is not sufficient to run their systems or keep them warm.
Getting rid of heat is definitely not a problem for spacecraft outside the habitable zone.