How to choose household photovoltaic modules?

1. Check component level

In the production process of photovoltaic modules, strict factory inspections are carried out to ensure their power generation performance. Domestic manufacturers generally classify the modules into three levels: A, B, and C based on their performance and appearance. A-level 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 its different appearance, it can be divided into A1, A2, A3 and other levels. A1 level refers to components with highly consistent color and electrical performance, which are of good quality; 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, generally with defects and severe color differences. Batteries with C-level components often suffer from physical damage, such as missing corners, edge chipping, and grid breakage. B. Due to defects and quality issues, C-level components cannot guarantee that their subsequent power and attenuation rate comply with national regulations, nor can they guarantee a service life of 25 years. I solemnly inform everyone that only A-level components can be openly circulated on the market, and any so-called B-level C-level component is selling counterfeit goods!

When purchasing components, it is necessary to choose top tier brands, purchase through formal channels, and choose reliable integrators, as the market is now mixed with fake, fake, and counterfeit 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-level components will not experience these situations (as shown in the following figure): battery color spots, color differences, bulges, broken grids, missing corners, edges, gaps, etc; Poor packaging of the component appearance, poor sealing, scratches on the backplane, scratches on the frame, scratches on the glass, etc.

2. Component certification

In addition to level and warranty, selecting components can also depend 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 the products have passed domestic and international testing standards, have safety and durability, and ensure the long-term stable operation and high profitability of photovoltaic systems. Authoritative certifications include CGC, CQC, TUV, UL, etc.


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 is 1000W/㎡, battery temperature is 25 ℃, AM=1.5 That is to say, the 260Wp component represents a power generation of 260W at STC And this parameter will decrease as the component ages.

The aging attenuation of components refers to the phenomenon of extremely slow power reduction during long-term use, with an annual attenuation of about 0.7% and a total attenuation of no more than 20% over 25 years Professor Shen Hui from the Solar Energy Research Institute of Sun Yat sen University collected about 3000 modules in China that have been in use for more than 30 years. Among them, the ones that performed well showed a attenuation of only 6% after 28 years of use. That is to say, a 260Wp component with reliable quality will still be at least 208Wp in 25 years, and if the situation is good, it may reach over 240Wp, thus ensuring the stability of the photovoltaic power plant's revenue for 25 years.