Bifacial Solar Modules could become the next big thing in renewable energy sector. With rising demand, the prices of PV modules have decreased exponentially. Now, since the technology is always moving, the improvement in efficiency of solar modules becomes a point of question. Industries started questioning if the bar for efficiency was already reached!
People have come to wonder if future solar improvements will be through system solutions, such as coupling solar with storage, rather than through module technology innovation. But, a newer innovation is paving the way to the next generation of module technologies that will revolutionize solar efficiency for many applications.
Bifacial solar modules have the capability to generate electricity by capturing light from both sides of the module. It is expected that bifacial solar module is going to move the market in coming few years. Because bifacial modules can generate power from the front and back of the module, they require less labor costs and balance of system costs to produce the same amount of energy. They can also produce more energy from the same project footprint, with minimal additional installation costs. Bifacial modules offer substantial savings.
But, what really is bifacial solar module and how do they work?
Bifacial solar cells are designed to allow light to enter from both sides. They typically employ a front surface design similar to that used in industry‑standard screen printed solar cells, with the major difference being the structure of the rear surface contact. Instead of covering the entire back surface with a reflective aluminium contact, a ‘finger’ grid is used in its place in order to allow sunlight through the rear. The silicon material used for bifacial solar cells must be of superior quality such that photo-generated electric charges near the rear surface can contribute to power production as they travel towards the ‘emitter’ on the front surface. This design also necessitates the use of transparent encapsulating materials (i.e. glass) on both sides of modules.
Image Source: Gamma Solar via NREL
Vincent Ambrose, Canadian Solar’s general manager for North America said,
“The challenge with bifacial has always been the unpredictability of the power output because it’s dependent upon the substrate behind the modules—a white commercial roof, a dark comp shingle, grass, gravel. It’s hard to model what the module is going to produce. The financing community is coming around on bifacial and the cost structure is coming down. We’ll be hearing more about that technology in the coming two or three years.”
Chinese panel manufacturer LONGi Solar believes we’re entering a new era of PV, one where high-efficiency modules are supreme. Bifacial technology supports the concept of using quality materials for high-energy yields.
Source: Solar Power World