Bifacial solar panels offer many advantages over traditional solar panels. Energy can be produced on both sides of a bifacial module, increasing total energy production.
They tend to be more durable as both sides are UV resistant and potential induced degradation (DIP) issues are reduced when the bifacial module is frameless. The cost of system balance (BOS) is also reduced when more power can be generated from the bifacial modules in a smaller footprint.
Many companies currently market bifacial modules. As more manufacturers enter production, bifacial modules become more economically competitive.
What is a bifacial solar panel?
Bifacial solar panels produce solar energy from both sides of the panel.
While traditional opaque sheet metal panels are monofacial, bifacial modules expose both the front and back of the solar cells.
When bifacial modules are installed on a highly reflective surface (such as a white roof or light-colored stone terrain), some bifacial panel manufacturers claim that power can be increased by up to 30% simply due to the extra power generated from behind.
Bifacial panels have different designs. Some are framed and some are not. Some are double glazed and others use transparent back sheets. Most use monocrystalline cells, but there are polycrystalline designs. The only thing that does not change is that the energy is generated on both sides.
There are double glazed frameless panels which expose the rear of the cells but are not bifacial. True bifacial modules have contacts/busbars on the front and back of their cells.
How are bifacial panels installed?
How to mount a two-sided panel depends on its type.
A framed bifacial module may be easier to install than a frameless module, simply because traditional mounting systems are already adapted to framed models. Most bifacial module manufacturers supply their own brand-specific mounting brackets, taking the guesswork out of installation.
In the case of frameless bifacial modules, the module clamps usually have rubber protectors to protect the glass, and special care must be taken to avoid over-tightening the screws and damaging the glass.
The more a bifacial panel is tilted, the more power it will produce due to its bifacial properties. Bifacial modules mounted flush with the roof prevent reflected light from reaching the rear of the cells. This is why bifacial modules work best on flat roofs and in ground installations, as there is more room for tilting and bouncing of reflected light off the back of the modules.
The mounting system itself can affect the performance of bifacial modules. Rack systems with support rails, typically covered by the backsheet of a monofacial module, will shade the back rows of bifacial cells. Bifacial panel junction boxes have been made smaller or separated into multiple units positioned along the edge of the panel to also avoid shading. Mounting systems and racks specifically designed for bifacial installations eliminate the problem of rear shading.
The future of bifacial panels.
Manufacturers expect bifacial modules to be a major player in the industry in the coming years.
As costs come down, they will become more widely used and popular, especially in tight spaces.
In the future, the best performing panels will prevail. Bifacial technology uses quality materials to obtain high energy performance.
Some experts believe that bifacial modules are the future of the sector.