Glass for PV applications

The Function of Solar Panel Glass

Solar panel glass performs a few main functions for solar panels, including:

Protection from damage — Tempered solar panel glass serves as a protective layer for solar panels, preventing environmental factors like vapors, water, and dirt from damaging the photovoltaic cells. Tempered solar panel glass also provides high strength, excellent transmissivity, and low reflection.

Durability and safety — Tempered glass offers up to four times more strength than standard glass. This strength is critical as the solar panel’s front sheet requires lasting protection against the elements. Thanks to the thermal and chemical processes that produce tempered glass, it is also known as toughened or safety glass. Tempered glass is safer to use because it shatters into many smaller pieces when broken, reducing the probability of accidental injury. 

Weight — Glass must be of a certain weight for solar panels. The industry standard weight for a 3.2 mm thick solar panel glass is around 20 kg. Tempered glass can provide this minimum weight, avoiding the dangers of cheap, lightweight solar panel glass.

Types of Solar Panel Glass

Solar panel glass may consist of two main types: thin-film or crystalline. Both have distinct features to keep in mind.

Thin-Film — Thin-film glass is lightweight, cost-effective, and easy to install. They are made of standard, non-tempered glass and can be as thin as 2.5 mm. Thin-film solar panels are lightweight because the glass encloses the panel without a frame. They require the most space and have the lowest efficiency out of all the solar panel glass options.

Crystalline — Solar panels made with crystalline glass tend to have a thickness of 3 to 4 mm, which adds more stability. This glass has a unique rough surface, which enables the glass to bond well with the panel’s EVA film for lamination purposes. Smooth glass can lead to gradual delamination. There are two subtypes of crystalline glass: monocrystalline and polycrystalline. Both of these crystalline panels require a fabrication method that involves producing silicon crystals that are cut into thinner wafers for use in solar panel glass.

Monocrystalline — These panels feature a sleek look and optimal efficiency, but they’re slightly more expensive than polycrystalline glass.

Polycrystalline — These are less expensive than their monocrystalline counterparts, at the cost of reduced visual appeal and efficiency.