A Universal Route to Realize Radiative Cooling and Light Management in Photovoltaic Modules

Abstract

Photovoltaic (PV) modules are not only an opto‐electrical system, but also opto‐thermal one, where the optical, electrical, and thermodynamic domains are strongly coupled. The means to suppress both light and heat losses in PV modules remains undeveloped. Herein, a universal route to realize both radiative cooling and light management via the ultra‐broadband versatile textures is proposed, originating from the interaction with the visible, near‐infrared, and mid‐infrared electromagnetic waves (EMWs) via geometric, diffractive, and subwavelength optical effects. The sol–gel imprinted ultra‐broadband textures exhibited a near‐unity infrared emissivity over 0.96 at the atmospheric window between 8 to 13 μm for radiative cooling, and a solar transmittance and haze above 0.94 and 0.95 at the wavelengths from 350 to 750 nm, respectively, for light management. Applying the ultra‐broadband textures imprinted glass to silicon PV modules as an encapsulant cover, the short‐circuit current and conversion efficiency were increased by 5.12 and 3.13% in relative terms, respectively. The fabrication of such ultra‐broadband versatile textures was photolithography‐free, scalable, and PV industry compatible, which provided a cost‐effective, long‐term durable, and energy‐efficient means to both light and thermal management through ultra‐broadband matter‐EMW interaction not only in PV modules, but also various opto‐electro‐thermal devices.

Metamaterial-Based Radiative Cooling: Towards Energy-Free All-Day Cooling

“…A large variety of shapes and designs have been probed to find the most effective solution. Nanorods, cones, disks, and gratings have all been utilized to prove the usefulness of nanophotonic designs for radiative cooling, demonstrating similar cooling powers as simple film-type structures, but with the added complexity comes an [65], (e) random porous structure [69], (f,g) SiO 2 microparticles [71,73], and (h) porous polymer [74] were reported.…”

“…Lu et al [65] applied a unique fabrication method of modified silica sol-gel imprinting, which makes it possible to increase the durability of the device for real-life applications (Figure 4d) with an average emissivity measured to be greater than 96% in the atmospheric window region. This [41], (b) photonic crystal structure [42], (c) conical shape array [43], (d,e) antenna structures [30,48], (f-h) metasurfaces [54][55][56], (i,j) gratings [57,59], and (k) sphere arrays [60] have been reported.…”

“…Lu et al [65] applied a unique fabrication method of modified silica sol-gel imprinting, which makes it possible to increase the durability of the device for real-life applications (Figure 4d) with an average emissivity measured to be greater than 96% in the atmospheric window region. This method could be utilized in radiative cooling applications such as textiles [66][67][68].…”

“…Therefore, this easy and scalable process, utilizing random particles, is a possibility for low-cost, easy-to-apply coatings that can be used for radiative cooling. [63,7], (c) acrylic resin in TiO2 [64], (d) SiO2 random antenna-shaped particles [65], (e) random porous structure [69], (f,g) SiO2 microparticles [71,73], and (h) porous polymer [74] were reported.…”

Passive radiative cooling and other photonic approaches for the temperature control of photovoltaics: a comparative study for crystalline silicon-based architectures

“…3. Several studies 10,11,12,13,14 utilizing photonic radiative coolers for solar cells have emerged over recent years. In our study we pick two of them to highlight and distinguish the cooling gain that arises in one case mostly by the photon management at the optical regime (Wei Li et al 13 in 2017) and in the other case at the mid-IR (Linxiao Zhu et al 10 in 2015).…”