Open AccessAngularly selective microstructured surface for tuning seasonal sunlight interaction
Author(s) -
Kazutaka Isoda,
Kouji Nagata,
Daisuke Ogawa,
Mizue Ebisawa,
Nathan Hagen,
Yukitoshi Otani
Publication year - 2019
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.036426
Subject(s) - optics , materials science , selective surface , irradiance , reflectivity , solar irradiance , absorption (acoustics) , sunlight , planar , optoelectronics , meteorology , physics , computer graphics (images) , computer science
In the temperate latitudes, high-reflectivity exterior surfaces save energy spent on ventilation and cooling during summer, but cost energy on heating in winter. Angularly selective surfaces that adjust their reflectivities by sun position allow beneficial effects in both seasons - high reflectivity in summer and high absorption in winter. Here we show how a planar microstructured surface can produce such an angularly selective behavior and estimate its energy efficiency under direct solar irradiance at 35° N. Results show that such an ideal angularly selective surface has the potential to improve efficiency by up to 43.2% compared to a conventional concrete surface. Numerical results for an aluminum one-dimensional periodic structure indicate that it achieves a 25.7% improvement of efficiency. Finally, we validate the designed structure by measuring the reflectivity of the fabricated surface at a series of angles.