Powering Solar: The Essential Role of EVA Films in G2G and G2B Module

Ethylene Vinyl Acetate (EVA) films play a critical role in the performance, longevity, and reliability of solar modules. By protecting photovoltaic (PV) cells from environmental stressors and ensuring mechanical stability, EVA film is an essential component of solar module design. Therefore, selecting the right EVA film is crucial.

This polymer acts as a cushioning layer between the PV cells and the protective front sheet (usually glass) and back sheet (either glass or polymer), ensuring that the cells remain intact and operational throughout the module’s lifetime. During the lamination process, EVA film melts and encapsulates the solar cells, providing adhesion and a stable structure.

As the market for solar modules diversifies into Glass-to-Glass (G2G) and Glass-to-Backsheet (G2B) configurations, understanding how EVA interacts with different materials is key to optimizing performance.

EVA Films in G2G (Glass-to-Glass) Solar Modules

Glass-to-Glass (G2G) modules are increasingly favored for their superior durability and long-term performance. These modules consist of PV cells encapsulated between two layers of glass, providing enhanced mechanical strength and improved resistance to environmental factors such as moisture, wind, and thermal expansion.

In G2G modules, EVA acts as the binding agent between both glass layers and the solar cells while also offering excellent UV protection and shock absorption. Important characteristics to consider include:

• Thermal Expansion: Given the dual glass structure, the thermal expansion properties of the EVA film are critical. The film must remain stable despite the stress induced by wide temperature fluctuations.
• Moisture Resistance and Durability: G2G modules are often used in harsher environments, such as desert installations or floating solar projects, where moisture resistance and mechanical durability are essential. EVA plays a pivotal role in ensuring the module remains functional for over 25 years, even in challenging conditions.

EVA in G2B (Glass-to-Backsheet) Solar Modules

Glass-to-Backsheet (G2B) is the most common solar module configuration. In these modules, EVA encapsulates the solar cells between a front glass sheet and a polymer backsheet, offering essential protection against moisture ingress, UV radiation, and mechanical damage.

For G2B modules, key EVA characteristics to focus on include:

• Strong Adhesion: EVA films in G2B modules must offer high transparency to allow maximum sunlight to reach the solar cells. Strong adhesion between the glass, backsheet, and solar cells is critical for maintaining mechanical stability over time.
• UV Resistance: While the backsheet serves as the primary barrier against environmental degradation, UV-resistant EVA further prevents the solar module from becoming yellowish after exposure to sunlight.

It is important to note that all EVA properties—such as transparency, thermal stability, adhesion, UV resistance, and moisture protection—are essential. Manufacturers can significantly enhance the performance and durability of their modules by focusing on these factors, resulting in a stronger return on investment.

Explore Suppliers of High-Quality EVA Films with Mappes

Poor selection or application of EVA film can lead to problems such as delamination, reduced power output due to yellowing, moisture ingress, or electrical issues.

For solar module manufacturers seeking a competitive edge, connecting with an EVA manufacturer that understands your needs and meets global quality standards can be a time-consuming challenge. At Mappes Solar Ecosystem, we’ve mapped the EVA Film value chain, allowing you to explore suppliers worldwide, including those in India, and connect with them directly.

We’ve also partnered with a leading Chinese solar encapsulant film supplier. If you're interested in connecting with them, drop us a DM to learn more.