Home » Environment

Understanding Bifacial Solar Panels: Technology, Benefits, and Drawbacks

Explore the dual-sided innovation of bifacial solar panels, their technology, advantages, ideal use cases, and potential challenges.

By Medha deb

Created on Sep 26, 2025

Explore the dual-sided innovation of bifacial solar panels, their technology, advantages, ideal use cases, and potential challenges.

What Are Bifacial Solar Panels?

Bifacial solar panels are advanced photovoltaic devices specifically engineered to capture sunlight on both their front and rear surfaces. This means, unlike traditional solar panels (monofacial modules) that absorb sunlight exclusively from the side facing the sun, bifacial panels are designed to convert both direct sunlight and reflected light—which bounces up from the ground or surrounding objects—into electricity. This dual-surface approach substantially boosts their total energy output, often making them a preferred choice for installations aiming to extract maximum efficiency from limited space.

How Bifacial Solar Panels Work

To understand the unique performance of bifacial modules, it’s important to look at their core construction and how they interact with light:

Dual-sided photovoltaic cells: Photovoltaic (PV) cells are placed between two layers of transparent material, usually glass, allowing light to penetrate from both the front and rear of the panel.
Front-side absorption: The front of the panel captures direct sunlight, much like monofacial panels.
Rear-side reflection: The rear surface captures diffused and reflected sunlight from the ground or nearby surfaces. Highly reflective surfaces such as white roofing membranes, sand, snow, or concrete enhance this reflection.
Electrical conversion: Both absorbed and reflected photons liberate electrons in the PV cells, generating power through the same photovoltaic effect as standard panels.

The total electricity generated is thus a combination of the energy created by light hitting both sides, often resulting in a 10%–30% increase in power output over typical monofacial panels.

The Technology Behind Bifacial Panels

Bifacial panels have evolved through decades of research and now incorporate innovations that maximize both performance and durability. Key aspects include:

Double glass or transparent backsheet: Unlike monofacial panels that often have a solid, opaque backsheet, bifacial modules usually employ glass or a clear polymer on both sides, allowing rear-side light penetration while also improving mechanical durability.
Cell types: Modern bifacial panels frequently use N-type monocrystalline silicon solar cells. Unlike traditional P-type cells, N-type cells experience lower degradation and fewer recombination losses, ensuring sustained efficiency over decades.
Framing options: While many bifacial panels are frameless to reduce shading on the rear, some use slim frames for added strength or easier mounting depending on the installation type.

Component	Purpose	Feature in Bifacial Panels
Glass Layers	Protect and seal PV cells	Transparent on both sides for dual sunlight exposure
N-type Silicon Cells	Power generation (higher efficiency, less degradation)	Common in bifacial panels for improved longevity
Junction Box	Electrical connections for energy output	Often centrally placed to avoid shading

Advantages of Bifacial Solar Panels

Up to 30% Higher Energy Yield: By leveraging both direct and reflected sunlight, bifacial panels often deliver 10–30% or more increased power production relative to traditional models. The actual gain depends on ground reflectivity, tilt, and installation height.
Improved Low-Light Performance: Bifacial panels produce more electricity at dawn, dusk, and during overcast weather by capturing diffused and ambient light on both faces.
Greater Durability and Longevity: Their double-glass or clear polymer construction enhances weather resistance, reducing risks of microcracks and extending operational life. Many bifacial modules come with longer warranties.
Versatility in Installation: They can be installed in various orientations (horizontal, vertical, or tilted) and are effective on ground mounts, rooftops, over water, or in carports and pergolas.
Consistent Performance: If the front surface is partially shaded, the rear can still contribute to power generation, resulting in more reliable production year-round.
Environmental Impact: Increased output per panel means fewer panels and support structures for a given energy target, leading to less material use and lower carbon footprint.

Limitations and Drawbacks

Higher Upfront Costs: Bifacial panels generally cost more per unit than monofacial panels due to advanced materials and more intricate manufacturing.
Installation Complexity: Maximizing rear-side energy capture requires careful design—such as optimal tilt, height above ground, and use of reflective surfaces (albedo). Installations without these optimizations may see minimal benefit over conventional designs.
Heavier Panels: The use of glass on both sides increases weight, affecting mounting requirements and sometimes complicating rooftop installations.
Limited Gains in Some Locations: In shaded environments or on dark, non-reflective surfaces (e.g., black roofs), the rear-side yield is low, reducing the technology’s advantage.
Potential for Soiling: While dual glass increases durability, soiling or debris buildup on the rear surface can reduce its effectiveness, so periodic cleaning may be necessary.

When Are Bifacial Panels Most Effective?

Bifacial technology works best in settings where rear-side reflection is maximized:

Above highly reflective surfaces—snow, sand, concrete, or light-colored rooftops
Commercial projects where large ground-mount arrays can be elevated and spaced to prevent shading, maximizing both direct and indirect sun absorption
Carports, awnings, and canopies where panels are elevated off the ground, allowing significant light to bounce onto their undersides
Floating solar farms due to water’s strong reflectivity and cooling effects

Conversely, they are less suitable for locations with extensive shading, minimal rear reflection, or space constraints that require panels to be installed directly on dark, non-reflective surfaces.

Environmental Impact and Sustainability

Bifacial solar panels contribute to sustainability by:

Reducing the number of panels required for a specific energy output, thereby lowering material use
Increasing total energy production per installation, accelerating the payback period and enhancing return on investment
Lowering the overall carbon footprint associated with generating renewable electricity

For companies and homeowners seeking to showcase sustainable practices, bifacial panels offer a visible, cutting-edge commitment to environmental stewardship.

Comparing Bifacial and Monofacial Solar Panels

Feature	Bifacial Panels	Monofacial Panels
Light Absorption	Front and rear	Front only
Potential Energy Yield	10–30% higher (with optimal conditions)	Standard
Construction	Double glass or clear backsheet	Opaque backsheet
Weight	Heavier	Lighter
Cost	Higher upfront price	Lower
Installation complexity	Requires more design consideration	Simpler, standard setups
Best for	Commercial, carport, floating, reflective ground installations	Residential rooftops, shaded areas, limited space

Key Considerations Before Installation

Surface Reflectivity (Albedo): The greater the albedo (reflectivity) of the ground beneath the panels, the more substantial the rear-side energy gains.
Mounting Height: Elevating panels off the ground allows more reflected light to reach the rear, improving output.
Tilt Angle: The optimal tilt depends on your latitude as well as the intended maximization of rear-side irradiation.
Shading: Both sides should be kept as free from obstructions and shadows as possible.
Cleaning and Maintenance: Dual-glass surfaces may require additional periodic cleaning for peak performance.

FAQs About Bifacial Solar Panels

Q: Can bifacial solar panels be installed on a typical home roof?

A: They can, but to maximize the technology’s benefits, installers should assess whether your roof allows enough rear-side reflection and space for air circulation. Flat, dark, or highly shaded roofs generally see little additional yield.

Q: How much more energy do they produce than regular panels?

A: In optimally designed systems with highly reflective surfaces, bifacial modules can produce up to 30% more electricity than monofacial panels, although typical gains range from 10% to 25%.

Q: Are bifacial panels more expensive?

A: Yes, their upfront pricing per watt is usually higher than standard panels. However, the boost in overall energy output and durability can result in better long-term value, especially for large or well-designed systems.

Q: What maintenance do bifacial panels require?

A: Although generally robust and durable, both surfaces should be kept clear of debris and shaded obstructions. In dusty locations or areas with frequent buildup, periodic cleaning of both sides is recommended.

Q: Which installations are most likely to benefit?

A: Ground-mount arrays on light-colored or reflective surfaces, carports, floating solar arrays, and commercial installations where design flexibility and space optimization are priorities.

Conclusion

Bifacial solar panels are a significant technological leap forward in the solar industry, offering a pathway to greater energy efficiency, longer lifespans, and improved financial and environmental benefits. Although they come with higher upfront costs and demand more thoughtful system design, the potential for increased energy production makes them an excellent choice in commercial and utility-scale settings — and for homeowners whose sites are especially well-suited to their strengths.

References

Author

medha deb

Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

Read full bio of medha deb