Encapsulants are polymer-based sheets used to integrate components (Glass, Cell, Backsheet, interconnects, etc.) in a solar panel.
To make solar PV modules (Solar Panels), the solar cells are laminated between 2 layers of the encapsulant. Encapsulants at both sides provide insulation to the cells from moisture, dirt, dust, and more importantly the passage to the light to reach the cells, while electrically insulating them. It also provides mechanical integrity by binding various parts of the PV modules (solar panels) together as mentioned above.
The primary function of Encapsulant can be explained as follows:
Provides Support:
The Encapsulant provides structural and positioning support to the solar cell in the solar panels' layout throughout manufacturing, transport, storage, installation, and its use.
Maintains optical transmittance:
It helps retain the optical connection between the solar cell and glass while ensuring that at least 90% of the light from the sun passes through to the solar cells with a maximum loss of 5% over 20-30 years or more.
It also allows UV light to enter the solar panel contributing to higher power generation, while preventing it from damaging the backsheet.
Maintains physical protection:
The Encapsulant also provides and maintains proper physical protection from weathering-induced and environmental damages such as stress cracks, UV degradation, yellowing, blackening, delamination, etc.
Maintains electrical insulation:
It maintains the electrical insulation between the solar cells and the electrical circuit elements during the lifetime of the photovoltaic module.
Maintains the integrity of the electric circuit:
The Encapsulant maintains the integrity of the electric circuit, which generates the necessary current and voltage in the presence of sunlight.
Data Credits:
Image Credits: RenewSys