In the dynamic landscape of solar technology, continual innovations in photovoltaic (PV) modules, commonly known as solar panels, play a crucial role in advancing energy efficiency and sustainability.
Among these breakthroughs, bifacial PV modules have garnered widespread attention for their outstanding advantages.
What are Bifacial PV Modules?
Traditional solar panels typically comprise monofacial PV cells enclosed between a front glass cover and a backsheet. In contrast, bifacial PV modules feature transparent layers on both the front and back, with bifacial cells positioned between them. This unique design allows these modules to harness sunlight from both sides, hence the name "bifacial."
Bifacial solar panels offer several key advantages over their monofacial counterparts, such as:
Increased Energy Production
One of the most significant benefits of bifacial glass-glass PV modules is their superior energy production. These modules can capture sunlight from both the front and rear (ground-facing) sides, making them highly efficient. When placed on a reflective surface, such as white gravel or snow, these modules can receive additional sunlight, which significantly boosts their energy output. Some studies say that bifacial modules can increase energy yield by up to 30% compared to traditional monofacial modules.
Higher Lifetime Energy Yield
Building upon the increased energy production, the bifacial nature of these modules delivers higher lifetime energy yields. This advantage becomes particularly evident in installations that are conducive to capturing reflected light. The inherent ability to harness sunlight from both sides leads to substantial gains in lifetime energy generation, setting them apart from their monofacial counterparts.
Enhanced Aesthetics
The transparent front and back covers of bifacial glass-glass modules provide a sleek, modern appearance that seamlessly integrates into various architectural and design applications. This aesthetic appeal makes them an attractive option for both residential and commercial solar installations.
Types of Bifacial Solar Panels & their Advantages
Bifacial solar panels commonly come in the following two configurations:
Bifacial Glass-Glass Solar Panels
Also known as dual glass or double glass solar panels, these panels feature transparent glass on both the top and bottommost (ground-facing) layers.
Some advantages of bifacial glass-glass panels include:
Superior Moisture Resistance
The best module manufacturers use POE (Polyolefin Elastomer) as the encapsulation material in Glass-Glass solar panels. Known for its exceptional moisture resistance, POE encapsulant boasts a significantly lower water vapour transmission rate (WVTR) compared to the commonly used EVA encapsulant in monofacial solar panels. This characteristic ensures that POE is less likely to permit moisture penetration into the solar panel, reducing the risk of damage to the solar cells and enhancing the panels' reliability, especially in high-humidity environments. Moreover, the POE encapsulant is the preferred choice for module makers when developing moisture-sensitive, high-efficiency solar panels like TOPCon, thanks to its ability to provide long-term protection and reliability.
RenewSys, the trailblazer in PV Encapsulant and Backsheet manufacturing, recently launched India’s first POE (Polyolefin Elastomer) Encapsulant specifically formulated for N-type TOPCon PV cells, CONSERV E – NT.
Enhanced Durability
Another unique feature of glass-glass solar panels is their exceptional resistance to mechanical loads. This resilience is attributed to the equal thickness of both the front and rear glass sheets, each measuring 2 mm. As a result of this uniform thickness, these modules undergo minimal compressive or tensile stress, providing optimal protection for the embedded solar cells. This inherent robustness renders them ideal for diverse installations, demonstrating their capability to withstand challenging environmental conditions.
Bifacial Glass-Backsheet Solar Panels
These modules feature a transparent glass layer on top and a transparent backsheet.
Some advantages of bifacial glass-backsheet panels include:
Lightweight
Bifacial Glass-Backsheet (G-B) modules are 17% lighter than Glass-Glass (G-G) modules. The reduced weight offers several benefits, including lower transportation costs, reduced risk of breakage during transit, decreased labour expenses, savings in balance of system (BOS) costs, improved efficiency in handling and installation, and lower environmental impact.
Optimized Power Gain
The transparent backsheet in bifacial glass-backsheet modules facilitates superior heat dissipation compared to panels with glass on the rear side, allowing them to capture more backside power. This optimization in power gain translates to increased energy production.
Ease of cleaning
The outermost layer of the transparent backsheet features stain resistance, and has hydrophobic properties, encouraging water droplets to easily roll off, carrying away dirt and dust in the process. This helps minimize dirt and dust accumulation on the backsheet surface and ensures minimal impact on energy generation.
Read more advantages of Bifacial Glass-Glass PV modules here.
Data credits:
RenewSys R&D
Image credits:
RenewSys