Photovoltaic glass typically consists of multiple layers. The top layer is made of transparent and protective glass, followed by a layer of photovoltaic cells.
What is a photovoltaic panel?
If we try to describe in a few words the structure, we could say that a photovoltaic panel is composed by a series of photovoltaic cells protected by a glass on the front and a plastic material on the rear. The whole of it is vacuum encapsulated in a polymer as transparent as possible.
One of the most important materials is the encapsulant, which acts as a binder between the various layers of the PV panel. The most common material used as an encapsulant is EVA – Ethylene vinyl acetate. It is a translucent polymer sold in a roll. It must be cut in sheets and deposited before and after the photovoltaic cells.
The front glass is the heaviest part of the photovoltaic module and it has the function of protecting and ensuring robustness to the entire photovoltaic module, maintaining a high transparency. The thickness of this layer is usually 3.2mm but it can range from 2mm to 4mm depending on the type of glass chosen.
Protection Layer: Usually made from glass, though in thin-film modules this can also be transparent plastic. Front Contact: The electric contact at the front, has to be transparent, as otherwise, light would not get into the cell.
How long do solar panels last?
Modules are expected to last for 25 years or more, still producing more than 80% of their original power after this time. A thin-film solar cell is made by depositing one or more thin layers of PV material on a supporting material such as glass, plastic, or metal.
Absorption Material: The heart of the module is the layer where the light is absorbed and converted into electric current. All materials used are semiconductors. In many cells, this is just one material, in most instances, silicon. However, in order to improve performance, there could be multiple layers of different materials.