People did the calculation: radiative cooling requires smaller surface area than solar panels. So, basically, a solar panel itself can radiate heat.
Have you done a calculation yourself?
Have you done a calculation yourself?
And even if viable, why would you just not cool using air down on earth? Water is used for cooling because it increases effectiveness significantly, but even a closed loop system with simple dry air heat exchangers is quite a lot more effective than radiative cooling
You don't have experience of being in space, so your "intuition" about cooling is worth literally nothing without formulas / numbers