You’ve probably noticed that the last few months have been populated by press releases from manufacturers stating that they would either increase their manufacturing capacity in PERC cell technology in order to produce high power and high efficiency solar panels, achieved efficiency records. So what is PERC technology really is ?
Literally, it stands for Passivated Emitter and Rear Cell. You also find the term Passivated Emitter and Rear Contact.
Professionally, PERC cell technology defines a solar cell architecture that differs from the standard cell architecture that has been in use for three decades and that is usually featured in all photovoltaic manuals.
As of today, the vast majority of crystalline solar cells produced follow the structure presented hereunder.
From top to rear:
– screen printed silver paste to form the contacts
– Anti Reflective Coating
– phosphorous diffused, boron doped silicon wafers that form the P-N junction
– aluminum Back Surface Field (Al-BSF)
– screen printed aluminum paste
What is the difference?
The main advantage of the PERC cell structure is that it enables manufacturers to achieve higher efficiencies than with standard solar cells which are reaching their physical limits. With the current state of the technology, it is possible to achieve up to 1% absolute gain in efficiency. While there are more steps in the manufacturing process, the gain in efficiency enables costs decrease, also at the system level. We should always keep in mind that the Holy Grail is to improve efficiency while reducing costs at the same time. And solar cell efficiency improvement is a contributor to the reduction of costs.
So this cell architecture is considered like presenting one of the best potential for producing high efficiency solar panels at competitive prices.