Novel Silica-Based PV Glass Cover Providing Higher Radiative Cooling and Power Production Compared With State-of-the-Art Glass Covers

Designer SiO2 Metasurfaces for Efficient Passive Radiative Cooling

“…In 2017, Lu and coworkers [65] utilized imprinting techniques to realize disordered pyramidal array structures, achieving an IR emissivity of ≈0.96 (Figure 6k). This value was further improved in 2021 by Fathabadi and co-workers [38] who demonstrated another disordered pyramidal array pattern with an emissivity close to 0.98 (Figure 6l).…”

“…Combined with Equation 1, the overall net cooling power obtained shows a direct proportionality with infrared emissivity. By considering a set of representative values of the average emissivity in the atmospheric transparency window ranging from the bulk case to the highest value reported obtained experimentally in the literature for a SiO 2 emitter (𝜖 avg = 0.98 [38][39][40] ), we see that the expected temperature drop can potentially increase from 5.3 °C to 8.8 °C, with a corresponding net cooling power enhancement of more than 27 W m −2 (Figure 2 and Table 1). How to achieve such high average emissivity values in practice for SiO 2 emitters and hence take full advantage of this additional net cooling power will be the main subject of this review.…”

“…For example, soda-lime glass and borosilicate glass are two common types of glass that are made with SiO 2 as their principal component, but they differ in their composition of added minerals and impurities, which results in variations of the optical properties. While fused silica is highly reflective in the atmospheric window region (≈70%), the added impurities in soda [ 54] Experimental 7 --Zhang et al ( 2019) [ 55] Experimental ---Ishii et al (2020) [ 56] Experimental 5.9 0.85 -Zhao et al (2019) [ 36] Silica fibers Numerical --178 Yalçın R A et al (2020) [ 57] Experimental 6.0 0.90 112 Tsai et al (2023) [ 28] 1D gratings Numerical 31.4 --Zhu et al ( 2013) [ 58] Numerical --114 Blandre et al (2020) [ 59] Numerical -> 0.90 98 Liu et al ( 2021) [ 60] Experimental 3.6 0.91 -Zhao et al (2022) [ 61] 2D micropatterns Experimental 13 --Zhu et al (2015) [ 62] Experimental 2 -600 Long et al (2019) [ 63] Numerical 9 ≈1.0 121 Li et al (2022) [ 64] Experimental 7 0.952 -Pinto et al ( 2023) [ 52] Numerical 17.6 ≈1.0 -Zhu et al ( 2014) [ 45] Experimental -> 0.96 -Lu et al (2017) [ 65] Experimental 9.2 > 0.98 -Fathabadi et al ( 2021) [ 38] Experimental 3 0.977 -Akerboom et al (2022) [ 39] Experimental 7.1 0.95 143 Ding et al (2022) [ 37] Experimental -0.947 -Arrés Chillón et al (2022) [ 66] Microspheres Experimental -> 0.94 -Atiganyanun et al (2018) [ 67] Experimental ≈6.9 --Fan et al (2020) [ 68] Numerical 73 --Whitworth et al (2021) [ 53] Experimental 19 >0.98 350 Fernandez et al (2019) [ 40] Experimental 5 0.946 -Lin et al (2022) [ 69] Numerical -0.916 80 Chen et al (2021) [ 70] lime glass reduce the reflectance in the reststrahlen band resulting in a relatively lower reflectance in the desired region (≈30%), compared to that of pure fused-SiO 2 . Various photonic techniques also have been utilized to enhance th...…”

“…Oelker et al [74] recently explored this idea by proposing a soda lime glass photonic microsphere-based array as an all-photonic radiative cooling approach for improved thermal management of solar cells. In this all-photonic approach related to photovoltaic systems, [38][39][40]45,61,62,65] the objective is to maximize the broad-band thermal emittance in the infrared range while optimizing light reflection in wavelength ranges where photons are not converted into photocurrent. These characteristics minimize heat gain due to inefficient light-electricity conversion while providing radiative cooling.…”

“…l) SEM photograph of the nanoscale pyramidal structure imprinted on the glass's surface and photograph of the fabricated glass with nano pyramidal coating. Reproduced with permission [38]. Copyright 2021, IEEE Electron Devices Society.…”