Table of Contents:
Key takeaways
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Bifacial solar panels can generate between 5% and 30% more energy than single-sided panels.
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The cost of bifacial panels and installing them is significantly higher than monofacial panels.
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Most homeowners aren’t likely to see a significant energy savings difference with bifacial panels for residential use.
Standard solar panels are designed to gather and convert sunlight from the sky above them. But you can also buy panels with solar cells mounted on both sides of the panel known as bifacial solar panels. By taking advantage of both direct sunlight and the light that bounces off surfaces like concrete, white roofing, or sand, bifacial panels can produce higher electricity output. They’re best for commercial solar installations, large-scale solar farms, or areas with highly reflective surfaces.
In this article, we’ll go over how bifacial panels work and how they differ from traditional solar technology. You’ll also learn about why they may not be worth the additional expense for your home.
How bifacial solar panels work
Bifacial solar panels generate electricity by capturing sunlight on both their front and rear surfaces, increasing overall energy production. These panels use transparent backsheets or glass so sunlight reflected off surfaces like the ground, water, or rooftops is absorbed by the rear side, letting silicon cells convert more light into electricity than traditional single-sided panels. This reflected light is also known as the albedo effect.
Structure and materials of dual-sided solar modules
There are a few key differences in how bifacial modules differ from standard solar panel construction. These include:
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Translucent backsheet: Single-sided solar panels typically have an opaque backsheet behind the PV cell layer. Bifacial panels use a translucent backsheet that allows them to collect light from both sides of the panels.
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Specialized PV cells: The silicon PV cells used in dual-sided panels typically have a different structure than those used in standard panels. These cells can be either monocrystalline or polycrystalline silicon, and are usually layered.
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Frame: Bifacial solar panels are usually mounted higher off the surface than single-faced panels to allow more light reflection underneath them.
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Rear glass: Whereas single-sided solar panels only have transparent glass on the top side of the assembly, bifacial panels use the same glass on the underside to allow light to reach the PV cells.
Bifacial solar panel efficiency in real-world conditions
Even though reflected light does not produce nearly as much electricity as direct sunlight, it can still generate a meaningful amount of energy. Bifacial solar panels can produce 5% to 30% more energy per panel than single-sided traditional panels. This makes them especially useful in situations where horizontal space is limited or when they are used to power a building with high energy needs, like in commercial applications.
That said, you might find a use for bifacial panels if you have an off-grid setup. Bifacial panels help you harvest more energy from the sun, which can be useful combined with a solar battery and reflective mounting surface.
Installation variables that affect bifacial module performance
The efficiency of bifacial solar panels is influenced by the type of panel you choose, the height at which they're mounted, the reflectivity of the surface below, and whether your system uses solar tracking technology.
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Solar panel type: Monocrystalline panels deliver the highest efficiency, while polycrystalline panels are slightly less effective.
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Mounting height: Elevating your bifacial panels well above the roof or ground lets more sunlight reach the surface underneath, increasing the amount of light that bounces back into the rear side of the panel.
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Surface reflectivity: The color and texture of the mounting surface are also important—light-colored, smooth surfaces like white rooftop coatings or concrete reflect more sunlight than darker or rougher materials.
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Tracking: Finally, if you install a tracking system—like those produced by NEXTracker or Array Technologies—your panels can follow the sun throughout the day, capturing more light and generating more electricity than fixed systems.
Comparing bifacial solar panels vs monofacial systems
While bifacial solar panels offer higher energy generation per panel, they’re often larger, pricier, and require more installation work than single-sided panels, making them less practical for most residential setups. Let’s compare both in detail.
| Factor | Bifacial Solar Panels | Monofacial Solar Panels |
|---|---|---|
| Light absorption | Absorbs light from both front and rear sides | Absorbs light only from the front side |
| Energy yield | Typically 5–30% higher due to rear-side generation | Standard yield based on front-side irradiance |
| Backsheet | Transparent or glass to enable rear-side light capture | Opaque (often white or black) |
| Albedo effect | Gains additional energy from reflected light (albedo effect) | Does not utilize reflected light |
| Installation types | Best with ground-mount systems or high-clearance setups | Suited for rooftop and fixed installations |
| System Cost | Higher initial cost due to advanced materials and mounting requirements | Lower cost; simpler structure |
| Performance in snow | Better snow shedding; rear generation continues | Prone to complete shutdown if front is covered |
| Soiling loss impact | Less affected due to rear-side compensation | More affected; cleaning has greater impact |
| Weight and structure | Heavier (often dual-glass); requires robust racking | Lighter; standard racking sufficient |
| Tracking system benefit | Works well with solar trackers for enhanced bifacial gain | Less benefit from tracking systems |
| LCOE (cost efficiency) | Potentially lower LCOE over time due to higher energy output | Stable, predictable LCOE with lower upfront cost |
| Use case | Utility-scale solar farms, reflective surfaces | Residential rooftops, small commercial projects |
Disadvantages of bifacial solar panels
The additional energy-generating potential of bifacial solar panels is an attractive selling point. However, there are significant downsides to bifacial panels—especially in residential applications. These include:
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Cost: Bifacial panels tend to cost 15% to 20% more than monofacial panels, requiring a substantially higher initial investment.
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Energy needs: Monofacial panels are usually more than sufficient for most residential energy consumption. That means that the additional expense of bifacial panels isn’t really necessary and may be wasted.
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Installation: Installing bifacial solar panels is more complex and requires more infrastructure than monofacial panels. That means installation costs are also likely to be higher.
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Appearance: Because bifacial panels need to be mounted high off a surface, they’re much more visible than single-sided panels. That can create an aesthetic that may be unpleasant for you and your neighbors.
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Roof surface: Bifacial panels work best when mounted on light-colored, smooth surfaces that reflect lots of light, such as on the roof of a commercial building. Most residential homes use dark-colored shingles that are designed to absorb light. This means there won’t be much light reflected to the back side of the panel, severely limiting the additional energy produced by the rear side.
Bottom line on bifacial photovoltaic panels
There’s no denying that bifacial solar panels are a remarkable technology. However, for most homeowners, these types of solar panels aren’t worth it. Depending on where your home is located, monofacial solar panels can likely supply all the energy you need. If they can’t due to environmental factors, it’s not likely that bifacial panels would make up the difference.
Still, bifacial solar panels are an excellent option for some specific applications. Large commercial buildings with roofs that can be modified to optimize light reflection may see significant benefits from using double-sided panels over monofacial ones.
FAQ about bifacial solar panels
Below are a few frequently asked questions about bifacial solar panels:
Are bifacial solar panels worth it?
Bifacial solar panels can be worth the additional cost in some situations. For example, large commercial buildings that have roofs that can be optimized to reflect sunlight and can support many panels may see substantial energy savings from using bifacial panels.
Can I use bifacial solar panels on my roof?
Unless your HOA prevents you from doing so, you can use bifacial solar panels on your roof. However, you aren’t likely to see enough of a difference in energy production compared to monofacial panels to make up for the additional cost of bifacial panels.
Where should bifacial solar panels be placed?
Bifacial solar panels should ideally be placed several feet above the surface on which they are mounted. In addition, double-sided solar panels can produce the most energy when the surface below them is light in color, smooth, and reflective.
What is the best angle for bifacial solar panels?
Studies have shown that the best angle for bifacial solar panels is 30 degrees. Tests have revealed a significant energy advantage at a 30-degree angle compared to a vertical mount.