If you're looking at bifacial solar panels for sale, one of the most important questions is how much electricity they can actually produce. Bifacial technology has become increasingly popular because these panels can generate electricity from both the front and rear of the module.
However, the amount of additional energy a bifacial panel produces depends heavily on how and where it is installed.
What Is Bifacial Energy Gain?
The additional electricity generated from the rear of a bifacial solar panel is known as bifacial gain.
The front of the panel receives direct sunlight, while the rear can capture reflected and scattered light from the surrounding environment.
This means a bifacial panel can potentially generate more electricity than a conventional monofacial panel of a similar specification.
However, there is no single percentage of additional generation that applies to every installation.
How Much More Energy Can Bifacial Panels Generate?
The additional energy generated by bifacial panels varies depending on the conditions around the installation.
Some systems may achieve relatively modest additional generation, while installations specifically designed to maximise rear-side exposure can achieve considerably higher bifacial gains.
Important factors include:
-
Surface reflectivity
-
Panel height
-
Panel spacing
-
Tilt angle
-
Orientation
-
Shading
-
Local solar conditions
-
Mounting structure
For this reason, it's better to calculate expected performance based on the specific installation rather than relying on a generic percentage.
Surface Reflectivity Is Important
The surface underneath the panels can have a significant effect on bifacial performance.
Light-coloured and reflective surfaces can send more sunlight towards the rear of the modules. Dark surfaces tend to absorb more sunlight and provide less reflected light.
For example, a ground-mounted system installed over a relatively reflective surface may provide better conditions for bifacial generation than panels installed directly above a dark surface.
Panel Height Can Affect Performance
The height of the panels above the surface underneath them can also influence how much light reaches the rear.
Elevating the panels allows sunlight to reach the rear from a wider range of angles. This can increase the amount of reflected light available to the rear solar cells.
This is one reason bifacial technology can be particularly attractive for ground-mounted systems and elevated solar structures.
Panel Spacing Matters
The distance between individual panels can also affect energy generation.
Panels installed too close together can block light from reaching the rear of neighbouring modules. Appropriate spacing allows more reflected and scattered light to reach the back of the panels.
Large solar installations have greater flexibility to optimise their layout, making careful spacing particularly important.
Orientation and Tilt
The orientation and tilt angle of the panels can affect the amount of sunlight available to both sides of the module.
A well-designed system should aim to maximise front-side solar exposure while also allowing useful reflected light to reach the rear.
The ideal configuration will vary depending on the location, installation type and available space.
Shading Can Reduce Bifacial Performance
Shading is another important consideration.
Buildings, trees, mounting structures and neighbouring panels can prevent sunlight from reaching the modules.
With bifacial systems, it's important to consider not only shading on the front but also obstructions that prevent light from reaching the rear.
A professional site assessment can help identify potential shading problems before installation.
Where Can Bifacial Panels Generate the Most Energy?
Bifacial panels can be used in a variety of solar installations, but some applications can provide particularly favourable conditions.
Ground-Mounted Solar
Ground-mounted systems can provide plenty of space beneath the panels for reflected light to reach the rear surface.
Commercial Solar
Large commercial installations can potentially benefit from carefully planned panel layouts and mounting structures.
Solar Car Parks
Elevated solar car parks can provide exposure to light on both sides of the modules, making bifacial panels an attractive option for some projects.
Residential Solar
Bifacial panels can also be used on residential properties, although the potential additional generation will depend heavily on the roof surface and mounting arrangement.
Does a Higher Wattage Mean More Energy?
When searching for bifacial solar panels for sale, it can be tempting to choose the panel with the highest wattage.
However, the wattage rating is only one part of the equation.
Panel efficiency, bifaciality, installation conditions, shading and the number of modules all influence the overall system output.
A slightly lower-wattage panel may sometimes be more suitable if it provides better efficiency or fits the available installation space more effectively.
How Can You Estimate Your Solar Output?
A professional solar installer can calculate an expected annual energy yield based on your specific site.
The assessment can take into account:
-
Solar irradiation
-
Panel specifications
-
Number of panels
-
Orientation
-
Tilt angle
-
Shading
-
Mounting configuration
-
Expected bifacial gain
This provides a more realistic estimate of potential energy production than simply using the panel's maximum power rating.
Are Bifacial Panels More Productive?
Under the right conditions, bifacial panels can produce more electricity than conventional monofacial panels because they can make use of additional light reaching their rear surface.
However, the technology doesn't guarantee the same increase in every installation.
The more effectively the system is designed to expose the rear of the panels to useful light, the greater the potential benefit.
Conclusion
Bifacial solar panels can increase energy generation by capturing sunlight from both sides of the module. The amount of additional electricity produced depends on factors including surface reflectivity, panel height, spacing, shading, orientation and installation design.
If you're searching for bifacial solar panels for sale, it's therefore important to consider the complete solar system rather than simply comparing panel wattages.
With the right installation conditions and careful system design, bifacial technology can help maximise the amount of renewable energy generated from your available space.
In the next article in this series, we'll look at how to choose the right bifacial solar panels for your solar system.
