Multifunctional coatings for solar module glass

Abstract

Currently, single‐layer antireflection coated (SLARC) solar glass has a dominant market share of 95% compared to glass with other coatings or no coating, for Si PV modules. This antireflection coating (ARC) results in an efficiency gain of 2–3%. However, there are issues with these SLARCs: (1) solar cell warming due to increased sub‐bandgap light absorption (by +0.4 ~ 1.2 K), counteracting the cell current gain and accelerating the aging of the solar panels, and (2) poor durability due to the coating's porous structure (typically lasting ≤5 years). This paper aims to develop a non‐porous multilayer coating (MLC) that is more durable and will act as a spectrally selective filter for solar modules. Studies have been conducted on MLCs in terms of optical, microstructure, mechanical, and durability properties compared with commercial single‐layer AR coatings. The MLCs showed superior performance in durability and benefit in reducing parasitic heat absorption in the non‐usable wavelength range. Also, a techno‐economic analysis model based on the multifunctional coating specifically to evaluate economic benefits has been developed.