Unlike bifacial modules, monofacial modules can only generate energy from the front of the solar panels. Bifacial solar panels can absorb light on both the front and back faces of the panels, this increases the efficiency of the solar panels.
In this article, You will learn more about bifacial solar panels, including their pros, cons, and efficiency.
What Are Bifacial Solar Panels?
Bifacial solar panels have solar energy cells on both the front and back side of the solar panel. This allows solar energy to be collected on the backside of the panel and enhance the energy output of the solar energy system. As a result, bifacial solar panels have a higher efficiency, as they are capable of capturing sunlight on both sides. Since they're made to be completely transparent, they are usually frameless without metal gridlines. This makes them stronger in structural integrity and easier on the eye.
Bifacial Solar Panel VS Traditional Solar Panel
Bifacial solar panels have two faces on the front and on the back sheet. You can see the solar cells sandwiched in two layers of glass and this increases its output especially if you install it on likely white concrete ground. Besides, it is mainly used in commercial or utility-scale applications where panels are elevated and angled away from a mounting surface, allowing light to reflect into the back of panel. This means that a bifacial solar panel can absorb light that is reflected off the ground or another material. However, on the traditional solar panel, you would have a white back sheet that can not get reflected light energy. So bifacial solar panels can be effective in certain applications in some ground-mounted systems or roofs.
How Much More Efficient is a Bifacial Solar Array?
When considering this question, taking full advantage of the bifacial solar panel is important. In order to achieve its max output, there are a couple of key considerations.
First, the more reflective the environment around the panels, the more energy they'll generate. A lighter-colored environment will reflect more light and boost its output performance. For example, the snow cover is great.
Second, there needs to be space for the reflected light to reach the back of the panel. This means bifacial panels don't make sense for rooftops where they'll sit almost right against the shingles. They're best utilized in large, commercial installations where they're up in the air on poles, with plenty of space for light to reflect against the back.
A 2018 study by LONGi Solar showed that bifacials can increase efficiency by 11% compared to a conventional solar panel system. The bifacial solar cell efficiency increase can be as high as 27% with a solar tracking system that tilts solar cells continuously toward the sun during its trajectory across the sky. The exact amount of extra energy will depend on the environment surrounding the solar panels themselves.
Pros & Cons of Bifacial Solar Panels
Bifacial solar panels are becoming increasingly popular, gaining attention due to both their affordability and efficiency. More homes and businesses are choosing to install bifacial over monofacial panels to reap the rewards, but do the advantages truly outweigh the disadvantages?
The Advantages of Bifacial Solar Panels
● Increased Efficiency. As bifacial modules can produce powers from both sides of the panel, there is an overall increase in energy generation.
● More Durable. As bifacial panels are frameless, and are covered both sides by tempered glass, they're often more durable. The tempered glass is weather-resistant, UV resistant and can withstand high temperatures and strong winds. As a result of their durability, bifacial solar panels are expected to have longer lifespans.
● Aesthetically Pleasing. Bifacial modules come in many designs, including frameless. Many see the complete glass frame more aesthetically pleasing compared to monofacial solar panels.
● Works Well in Diffuse Light. The extra surface area also means that bifacial panels perform better in diffuse light. Making the long-term costs lower than monofacial panels.
● Reduced PID. In the instance of a frameless bifacial panel, the solar cells are less likely to suffer from potential-induced degradation (PID). This is where electrical currents stray from their intended path and as a result corrodes the solar panels. Furthermore, bifacial panels without a metal frame don't require grounding, as there are no metal contacts on the exterior.
● Longer Warranties. Bifacial solar panels often come with a longer warranty of up to 30 years.
The Disadvantages of Bifacial Solar Panels
Bifacial solar panels do have their downsides, the largest of these downsides is cost. Bifacial solar panels themselves cost slightly more than monofacial solar panels. In addition, as bifacial solar panels are heavier, and require specialised equipment to take full advantages of the benefits, the installation costs are higher.
The larger cost difference comes from specialized solar racking for the bifacial panels.
Because bifacial solar panels require minimal shading behind the panels, specialized racking is installed to avoid blocking light that travels through the panels. This racking is more costly and requires experienced installers to do the job right. This all adds to the cost of a bifacial solar installation.
It is recommend bifacial modules for installation sites that can benefit for bifacial gain, meaning, that residential homeowners with roof mount installations are advised to seek other solar panel solutions. Under the right conditions, bifacial modules can produce more power with less equipment, saving in both initial investment cost, and increasing your return on investment.