Do-it-yourself radiative cooler as a radiative cooling standard and cooling component for device design

We demonstrate a simple, low-cost design of a selectively emissive radiative cooler using scotch tape and aluminum foil, which can be further augmented by higher quality metal deposition methods. This do-it-yourself radiative cooler achieves solar reflectance, long wavelength infrared emittance, and optical selectivity comparable to state-of-the art designs and is experimentally demonstrated as achieving a 7°C subambient temperature drop at night for the aluminized scotch tape and an average 2°C drop under a solar illumination of 965 W∕m² for the silvered scotch tape. In addition, an 11°C subambient temperature drop at night for the aluminized scotch tape was obtained when a convection shield was used. Detailed optical properties are presented for an ultrawide wavelength range and a ∼2π angle of emittance. Given its ease of fabrication and performance, we propose this set of materials as a control for future radiative cooling experiments and an effective radiative cooling accessory for passive cooling designs.