What is Bifacial Solar Module Technology?
Bifacial photovoltaic modules are solar panels designed to generate energy from both the front and back sides. Utilizing bifacial solar cells, their back side is encapsulated with transparent materials like glass or a transparent backsheet. This design allows the back side to capture diffused and reflected light from the surroundings, supplementing the energy produced by the front side.
Module with Transparent Backsheet Technology
Bifacial modules with transparent backsheet technology offer up to 20% power gain, influenced by the albedo effect and the design of the photovoltaic system.
What is the bifacial rate?
The bifacial rate is a crucial indicator for evaluating the performance of bifacial photovoltaic modules, which can generate energy from both sides. Also referred to as the bifacial factor or bifacial coefficient, it quantifies the ratio of the rear side’s power generation capacity to the front side’s under standard test conditions. For example, if the rear side of a bifacial module produces 350 watts and the front side generates 500 watts, the bifacial rate is calculated as 350/500 = 70%. This demonstrates that the rear side’s power generation capacity is 70% of the front side’s output.
Cell Structure Design
Bifacial solar panels have a unique cell structure with both a front and rear cell, enabling light capture from both sides to boost energy production. The rear side typically incorporates a back-contact or perforated design, minimizing shading from metallization and enhancing light conversion efficiency.
Comparison Between Bifacial And Monofacial Modules
| Feature | Bifacial Solar Panels | Monofacial Solar Panels |
|---|---|---|
| Energy Conversion | Absorbs sunlight from both front and back sides for higher energy production. | Absorbs sunlight only from the front side. |
| Installation Environment | Optimized for high-reflectance environments to maximize energy generation. | Has lower requirements for the installation environment. |
| Energy Generation | Produces 10-25% more energy than monofacial panels. | Offers relatively stable energy production. |
| Cost | Requires a higher initial investment. | Requires a lower initial investment. |
| Durability | Features a more complex structure, with long-term stability yet to be proven. | Offers a simpler structure with improved long-term stability. |
| Appearance | Modern design with an aesthetically pleasing appearance. | Features a traditional and classic appearance. |
| Land Area | Needs less land area to achieve the same energy production. | Requires relatively more land area for the same energy production. |
Different Types of Bifacial Photovoltaic Modules Available on the Market
PERC
- Efficiency: front side 19.4–21.2%; rear side 16.7–18.1%
- Bifacial rate: 70–80%
- Primarily used in commercial applications; gradually being phased out, typically utilizing p-type monocrystalline silicon cells.
IBC
- Efficiency: front side 22.0-23.2%; rear side 16.1%-18.2%
- Bifacial rate: 70–80%
- Primarily utilizes n-type monocrystalline silicon cells, featuring no metallic contacts on the front side.
- Primarily used in commercial applications with a market share of around 15%.
HJT
- Efficiency: front side 22.1-23.7%; rear side 21.4-23.3%
- Bifacial rate: 95–100%
- Primarily used in commercial applications with a market share of approximately 10%, typically utilizing n-type monocrystalline silicon cells.
TOPCon
- Efficiency: front side 22.0-23.3%; rear side 18.4-20.3%
- Bifacial rate: 70%–90%
- Utilizes n-type monocrystalline silicon cells, offering excellent photoelectric conversion efficiency and a low-temperature coefficient.
- Gradually becoming commercialized, with a market share of approximately 70%.
What Are The Key Factors That Impact The Energy Gain Of Bifacial Modules?
Height of the module from the ground:
Optimal module height for maximizing rear-side gain is between 0.7 and 1.2 meters, balancing cost and maintenance needs. While increased height enhances rear-side efficiency, gains diminish after 1.3 meters due to diminishing returns.
Ground reflectance:
To maximize energy production, bifacial modules utilize light reflected from the ground, with higher reflectance leading to improved efficiency. The reflectance ranking of ground surfaces is: snow > sand/concrete > soil > grass > water.
Module tilt:
To maximize solar radiation during installation, position the module at the optimal angle and direction. In Italy, the angle is about 10 degrees less than the local latitude: 35° in Milan, 32° in Rome, and 27° in Sicily. Orient the module southwest.
Distance between module rows:
Maintaining proper spacing minimizes shading and ensures even illumination while striking a balance between production efficiency and overall costs, tailored to specific project requirements.
Ground reflectance:
To avoid shading the rear side, crossbars should be positioned at the module’s edges. The design must also consider how the rear side and surrounding environment affect energy production gain.
Strategic Application Scenarios For Bifacial Solar Modules
The Bifaciality of Solar Panels: A Comprehensive Guide from Principles to Applications
October 28, 2024
Answers to Common Questions About Bifacial Solar Modules
Learn more about Bifacial technology
Absolutely! Bifacial solar panels seamlessly integrate with solar batteries, heat pumps, and EV chargers, enhancing energy efficiency while promoting a sustainable and interconnected energy system.
Manufacturers state that bifacial solar panels offer up to 30% greater efficiency compared to traditional monofacial panels, increasing energy output and lowering the cost per watt.
Although bifacial solar panels may require a higher upfront investment, their superior efficiency and energy output lead to a lower overall cost per watt and a quicker return on investment.
With exceptional durability and structural integrity, bifacial solar panels have a lifespan of 25-30 years when properly maintained. To ensure reliability, we provide a 10-year comprehensive maintenance plan for enhanced customer satisfaction and peace of mind.