Solar photovoltaic glass is used as a surface encapsulation and protection material for solar panels which plays key role for the long-term use of solar panels.
The panel glass used in small solar panels is tempered glass with low iron content and ultra-white glossy or suede. The glossy glass is also called float glass, and the suede glass is also called rolled glass. The thickness of commonly used panel glass is generally 3.2mm and 4mm. The thickness of building photovoltaic glass is 5-10mm. No matter the thickness, the light transmittance is required to be more than 90%. The wavelength range of the spectral response is 320-1100nm. For infrared rays with a wavelength greater than 1200nm, solar glass has a higher reflectivity.
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Small Solar Panel from BlueSolaria
Low iron means that this glass has a lower iron content than ordinary glass, and the iron content (iron trioxide) ≤150 × 10-6, thereby increasing the light transmittance of the glass. Ultra-white refers to that because this glass has a lower iron content than ordinary glass, this glass is whiter than ordinary glass from the edge of the glass, and ordinary glass is greener from the edge.
Suede means that in order to reduce the reflection of sunlight, the surface of the glass is subjected to physical and chemical antireflection treatments to make the glass surface fluffy, thereby increasing the amount of light incident. Some Chinese manufacturers also use sol-gel nanomaterials and precision coating technologies (such as magnetron sputtering method, double-sided immersion method, etc.) to apply a thin film containing nanomaterials on the glass surface. This coated glass can not only significantly Increasing the light transmittance of the panel glass by more than 2% can also significantly reduce light reflections, and also has a self-cleaning function, which can reduce rain, dust and other pollution on the surface of the solar cell panel, keep it clean, reduce light attenuation, and improve the power generation rate of solar module is 1.5% to 3%.
Temperature treatment is to increase the strength of the glass, resist the impact of wind and sand and hail, and protect the solar cells for a long time. The tempering of panel glass is to heat the glass to about 700 ° C through a horizontal tempering furnace, and use cold wind to quickly and uniformly cool it to form a uniform compressive stress on the surface and a tensile stress on the inside, which effectively improves the bending resistance of the glass. And impact resistance. After the panel glass is tempered, the strength of the glass can be increased by 4 to 5 times than that of ordinary glass.
In addition to the above characteristics, what are the unique advantages of glass used in solar modules?
1. Low self-bursting rate
Using high-purity raw materials, it does not contain various detonating impurities compared to ordinary glass, which greatly reduces the self-bursting rate after tempering, which can effectively reduce the defective rate of photovoltaic solar modules during production and use.
2. Color consistency
As the technology matures, ultra-white glass uses the world's advanced colorimeter and analysis software to ensure the consistency of glass color.
3. High visible light transmittance and good permeability
Visible light transmittance greater than 91.5%, with crystal-clear quality. The laminated solar panel can absorb sunlight to the greatest extent.
4.Low UV transmittance
Compared with other ordinary glass, solar-grade glass can filter most of the ultraviolet rays, which can effectively protect the solar cells, EVA and backsheet inside the solar panel.
Post by Julie Huang of BlueSolaria.
