"Like white paint. A traditional solution."
Not good enough for a place as hot as this. White still absorbs some heat, which in this case is still too much. You need something with much higher reflectivity: something closer to silver paint (like how the original "silver screens" really were silver instead of white to reflect more light from the film projectors). But silver's precious, so we need a more economical way to achieve the same feat.
Biting the hand that feeds IT
