The construction of custom solar panels varies slightly depending on the lamination method and the materials used. The following is a brief introduction to the construction of tempered glass solar panels and ETFE solar panels.
1. Solar Panel Construction of Tempered Glass Solar Panels
Tempered Glass / EVA / Solar Cell / EVA / Backsheet
2. Solar Panel Construction of ETFE Solar Panels
ETFE film / EVA / Solar Cell / PCB
The role of tempered glass is to protect the solar cells, the selected photovoltaic glass must have high light transmittance (generally more than 91%), and requires ultra-white tempering treatment. The thickness of photovoltaic glass is either 3.2mm or 2.0mm. The most commonly used is the 3.2mm thick glass.
EVA is an important encapsulant material, which is used to bond tempered glass and solar cells. It is usually cut into a thin sheet that can be inserted at the front and rear of the solar cells. The quality of transparent EVA material directly affects the lifespan of the solar panel. Should EVA be exposed to the air, it will easily age and turn yellow, thus affecting the light transmittance of the solar panel, and power generation quality.
The thickness of EVA ranges from 3mm to 4.5mm; among them, 4mm and 4.5mm are used the most.
Solar cells convert sunlight into electricity via the photovoltaic effect. They are the core parts of solar panels. Generally speaking, the power of a solar panel is proportional to the area of the solar cell.
The function of the backsheet is to seal, insulate and waterproof. Therefore, the selected backsheet materials such as TPT and TPE must be resistant to aging.
The backsheet is available in white and black. The white backsheet is commonly used, but some clients choose to use the black backsheet in order to maintain the color consistency with the application product and to be aesthetically pleasing.
ETFE film is a film used to protect solar cells inside solar panels. Its thickness is usually less than 0.2mm, making it thin and light. In addition, it has the characteristics of resistance to temperature changes, high light transmittance of up to 95%, high self-cleaning, corrosion resistance, and long service life.
IBC Solar Cell
ETFE solar panels adopt IBC solar cells (interdigitated back contact) with efficiency up to 24%, to achieve a higher power output in a limited area. Traditional solar cells achieve energy conversion by having front contacts in the cell, while IBC solar cells have the contacts on the rear side, instead of placing them in the front of the cell. This allows them to achieve higher efficiency due to reduced shading on the front of the cell, and also increases the aesthetics since no contacts are visible on the front. IBC solar cell technology also improves the temperature coefficient, which means an IBC solar panel can deliver a better performance in hot climate installations. It also has excellent performance under low light conditions.
WSL Solar has been a quality and professional manufacturer of custom solar panels, solar mini panels, IoT solar panels and solar solution provider in China since 2006.
Source of origin: https://www.wsl-solar.com/Product_News/2022/1212/Custom-Solar-Panel-Construction.html