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Title: High albedo daytime radiative cooling for enhanced bifacial PV performance
We present a radiative cooling material capable of enhancing albedo while reducing ground surface temperatures beneath fielded bifacial solar panels. Electrospinning a layer of polyacrylonitrile nanofibers, or nanoPAN, onto a polymer-coated silver mirror yields a total solar reflectance of 99 %, an albedo of 0.96, and a thermal emittance of 0.80. The combination of high albedo and high emittance is enabled by wavelength-selective scattering induced by the hierarchical morphology of nanoPAN, which includes both thin fibers and bead-like structures. During outdoor testing, the material outperforms the radiative cooling power of a state-of-the-art control by ∼20 W/m2and boosts the photocurrent produced by a commercial silicon cell by up to 6.4 mA/cm2compared to sand. These experiments validate essential characteristics of a high-albedo radiative-cooling reflector with promising potential applications in thermal and light management of fielded bifacial panels.  more » « less
Award ID(s):
2144662
PAR ID:
10483720
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
De Gruyter
Date Published:
Journal Name:
Nanophotonics
Volume:
0
Issue:
0
ISSN:
2192-8606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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