In the production process of photovoltaic modules, strict factory inspections are conducted to ensure their power generation performance. Domestic manufacturers generally classify modules into three levels: A, B, and C based on performance and appearance. A-class components have excellent performance, generally referring to components with high efficiency and good electrical performance consistency, with a lifespan of at least 25 years; According to their different appearance, they can be divided into levels such as A1, A2, A3, etc. A1 level refers to components with highly consistent color and electrical performance, which is the highest quality level; A2 components generally have significant color differences; A3 has more scratches than A2, but it does not affect normal use. The efficiency of B-level components is lower than that of A1 level components, and there are generally defects and significant color differences. The battery of C-level components often has physical damage, such as missing corners, broken edges, and broken grids. B. Due to defects and quality issues, C-level components cannot guarantee that their subsequent power and attenuation rates will comply with national regulations, nor can they guarantee a service life of 25 years. I solemnly declare that only A-grade components can circulate openly in the market, and any so-called B-grade or C-grade components are selling counterfeit goods!

When purchasing components, it is necessary to choose top tier brands, purchase through legitimate channels, and choose reliable integrators, because the market is now mixed with good and bad products, and counterfeit, fake, and inferior components may also be encountered. If we only look at the components themselves, we can roughly distinguish between good and bad components. Simply put, A-class components do not exhibit these conditions (as shown in the figure below): battery color spots, color differences, bulges, broken grids, missing corners, broken edges, notches, etc; Poor packaging and sealing of component appearance, scratches on backplate, frame, glass, etc.

2. Component authentication

In addition to grade and warranty, selecting components can also be based on the certification they have passed. Component manufacturers comprehensively certify the quality of photovoltaic modules through various testing and certification agencies, proving to customers that their products have passed domestic and international testing standards, possess safety and durability, and ensure the long-term stable operation and high returns of photovoltaic systems. Authoritative certifications include CGC, CQC, TUV, UL, and others.

3. Component attenuation

The 260W photovoltaic module we often refer to strictly means 260Wp, where p represents peak and its peak power is 260W. The testing conditions are all "Standard Test Conditions" (STC): irradiance of 1000W/㎡, battery temperature of 25 ℃, AM=1.5. In other words, a component with 260Wp represents its power generation of 260W at STC, and this parameter will decrease as the component ages.

The aging decay of components refers to the phenomenon of extremely slow power reduction during long-term use, with an annual decay of about 0.7%, and a total decay of no more than 20% over 25 years Professor Shen Hui from Sun Yat sen University's Institute of Solar Energy collected about 3000 modules in China that have been in use for more than 30 years, among which the best performing ones only decayed by 6% after 28 years of use. That is to say, the reliable quality of 260Wp modules will still be at least 208Wp modules after 25 years, and if the situation is good, it may not reach 240Wp or more, thus ensuring the stability of the photovoltaic power plant's revenue for 25 years.