Technical iterations of photovoltaic glass

It is difficult to have both massification and thin slicing, and the two application scenarios may diverge.

One of the key directions of technological iteration is thin-film. From a production and cost perspective, assuming an average yield of 84%, 82%, 80% and 75% for raw 3.2mm, 2.5mm, 2mm and 1.6mm glass respectively, and 97%, 95%, 95% and 93% for processed glass respectively, when the nominal thickness of glass is reduced from 3.2mm to 2.5mm, 2.0mm and 1.6mm respectively, the current capacity of the same The glass production capacity of the kiln can be increased by 17%, 41% and 60% respectively. At the same time, the capacity advantage of thin glass is expected to be further enhanced as the yield of thin glass increases and thickness is more accurately controlled.

Another important direction for technology iteration is towards larger sizes. Large wafer sizes are a mainstream trend in the current market as they can increase the power per wafer and reduce BOS costs without changing the size of the module. As wafer size and glass size need to be matched in PV modules, the trend is to increase the size of PV glass.

Due to performance limitations, it is difficult to combine thin wafer and large size of PV glass. As the thickness decreases, the impact and bending strengths of ultra-white calendered and float glass gradually decrease, while the combination of the two has a more detrimental effect on the mechanical properties of PV glass as the loading moment of the glass increases due to the larger size. This can also be used to explain the fact that the current maximum module power of distributed 2mm double-glazed modules can exceed 600 watts per module, but distributed 1.6mm double-glazed modules can only reach over 400 watts.

Therefore, we believe that the application scenarios of large-size PV glass and ultra-thin PV glass will be divided, with the former being used more in centralised PV plants and distributed plants with better stress conditions due to its higher single-piece power, and the latter being lighter (if we compare 1.6mm+1.6mm double-glazed modules with 2mm+2mm double-glazed modules, the difference in weight per square metre is about 2kg, accounting for about 10% of the overall The difference in weight between 1mm+1 6mm double-glass modules and 2mm+2mm double-glass modules is about 2kg per square metre, which is about 10% of the overall PV system weight.

The barriers to thinness are high, and in the context of the overall increase in the R&D cost rate of listed PV glass companies, there is a possibility of differentiated products with both thin and large characteristics. Photovoltaic glass large-scale need to upgrade the existing production line, the barriers mainly lie in the financial level rather than the technical level, so the homogeneity of the product is still difficult to change. And photovoltaic glass sheeting to improve the yield rate, the need for a higher degree of automation of the production line for the whole process of more detailed control, bubble control when melting, flatness control when forming, product strength control are higher requirements, combined with large size panels on the mechanical properties of more stringent requirements, the technical end of the barrier is higher. However, taking into account that in recent years, photovoltaic glass-related listed companies R & D expenditure rate is on the rise, and thin sheet for which the important R & D direction, so we believe that we need to focus on both thin, large characteristics of differentiated product development progress.

TCO conductive film glass is transparent conductive oxide coated glass, which is a transparent conductive oxide film uniformly coated on the surface of flat glass by physical or chemical coating methods. The glass is an important accessory for second generation CdTe thin film cells and third generation Chalcogenide modules. The competitive barriers to in-line coating are high due to the need for customisation of in-line equipment + complex modification of float production lines + experimentation with process parameters.