H-H. Hsieh
Industrial technology research institute,
Taiwan
Keywords: recyclable, solar module, encapsulant, relability
Summary:
Solar encapsulant material is a critical component in photovoltaic (PV) modules, as it protects the solar cells from external environmental factors, such as moisture and dust. The encapsulant material needs to have high chemical stability and optical performance to maintain its protective function over the long term. Ethylene Vinyl Acetate (EVA) has been the most widely used encapsulant material in c-Si solar modules for several decades. However, research has shown that PV degradation concerning the encapsulant materials is around 25%, which is higher than that of other module components. Therefore, there is a need to improve the performance and reliability of encapsulant materials.Accelerated aging tests, such as UV exposure, humidity, and thermal variation, have been developed to evaluate the durability and reliability of the encapsulant materials. In this research, a cyclic UV exposure/Thermal cycling test/Humidity Freeze sequential aging test, based on IEC 61215, was proposed to observe the power degradation in each step. The test results indicate that most encapsulant materials can sustain four aging cycles with a power loss of less than 5%. The humidity freeze test, which is conducted under high-temperature (85°C) and high-humidity (85% RH) conditions, results in a higher power drop (>0.5%) compared to other tests. This indicates that the key factors responsible for EVA degradation are humidity and temperature, specifically the humidity freeze test. The following UV exposure test helps to evaporate humidity from the module, resulting in a slight power recovery. These findings suggest that encapsulant materials with better resistance to humidity and temperature can improve the performance and reliability of PV modules. It is also important to note that different encapsulant materials may respond differently to aging tests, and therefore, further research is required to evaluate their durability and reliability. In conclusion, the cyclic UV exposure/Thermal cycling test/Humidity Freeze sequential aging test can provide valuable insights into the performance and reliability of encapsulant materials used in PV modules. Improving the durability and reliability of encapsulant materials can help to enhance the overall efficiency and lifespan of PV modules, making them more effective in generating clean energy for years to come.