Your Complete Guide to PERC Solar Cells

As solar panel technology improves, the market has seen all kinds of different types of solar panels pop up, claiming higher efficiency, better prices, and better materials. One such panel type is the PERC solar cell.  

Since the market share of PERC solar panels has been expanding recently – primarily due to an increased need for high-efficiency, low-cost solar panels to meet global clean energy needs – it’s essential to understand what makes PERC panels so unique, what types of PERC panels are available, and how and why you should be selling them today.   

What is a PERC Solar Panel? 

To understand how PERC solar panels work, it’s essential to understand the common issues you may encounter with a standard solar cell. First, traditional crystalline silicon solar cells generate power when light hits a silicon layer, loosening electrons and forcing them to flow through a wire. This converts around 20% of the photons passing through to electricity, but the rest is lost since the photons can miss the electrons and hit the silicon instead.  

Secondly, the sunlight can pass straight through the cell and generate heat instead. While this usually isn’t dangerous, it isn’t ideal for the system. It can still result in a loss of efficiency, which is the opposite of what panel manufacturers are looking for when working towards improving panel technology.  

This is where PERC panels come in handy. “PERC” stands for “Passivated Emitter and Rear Cell” or “Passivated Emitter and Rear Contact.” They are different from standard solar cells in the extra layer found on the back that you won’t find on your traditional cell. This extra layer allows for sunlight to be reflected back into the cell, allowing for an extra opportunity to generate additional power through exciting electrons without needing more panels or space.  

This extra sunlight reflection also prevents the heat generation and potentially high temperatures you’ll see with standard panels to help maintain the cell’s temperature and increase efficiency.  

While standard panels and PERC solar modules are different categories of solar panels, you can think of PERC as an upgrade to your traditional panel rather than an entirely new panel type. This is because PERC cells just have an additional layer that you won’t find on your average, run-of-the-mill solar cell but use the same materials and technology as other panels elsewhere in their build.  

Types of PERC Solar Modules 

Just like traditional solar panels, PERC modules come in both Polycrystalline and Monocrystalline varieties, with the same pros and cons you’ll find with their standard counterparts. Here’s a quick breakdown of each type of PERC solar module you’ll find on the market. 

Poly PERC Panels 

Polycrystalline PERC panels are your budget-friendly option. Made with fragments of silicon that are melted together, poly cells have a lower crystal purity and are the less efficient of the two. The upside to using poly panels lies in the price. Since they are easier to manufacture, the price is usually much less than mono panels.  

Poly panel manufacturers can also use the scraps from manufacturing mono panels to build these cells, using all the extra silicon that would otherwise go to waste, giving them a slightly smaller ecological footprint than their counterparts.  

Mono PERC Panels 

On the other hand, monocrystalline PERC panels are built with a single slice or wafer of silicon. A single piece of silicon does a much better job at generating electricity than many tiny shards of melted-down material, thus making it a much more efficient option for your system.  

Since mono panels are harder to manufacture, they are the more expensive option here. Still, the additional efficiency that can be enjoyed with a mono panel quickly makes up for its higher price tag. Additionally, since mono panels are usually the better choice in terms of panel type, you’ll see many more mono PERC panels around than you will with poly. This is also since their clean, black appearance is much more sought-after than the blue hue of poly panels.  

The Benefits of PERC Solar Cells 

As we mentioned earlier, PERC solar cells are much more efficient than standard panels, making them an excellent option for someone looking to make the most out of their solar system. This works out for almost anyone interested in solar energy but is especially useful for homeowners without a lot of roof space.  

Another reason for the growth in popularity of PERC solar cell technology is that they follow the same manufacturing process as standard cells, meaning that the same materials and machinery are required to build them as regular panels. This allows any silicon cell manufacturer to quickly begin production of their own brand of PERC panels without upgrading their facilities.  

Sure, the panel manufacturer has an extra cost with the additional materials and steps required to build a PERC module. Still, it is significantly less than adopting and building an entirely new solar cell technology from scratch. The slight extra cost that will then be passed on to the customer can then be made up quickly from the upgrade in solar cell efficiency they’ll enjoy over the life of their system. 

Offering PERC cells is also an excellent option for solar companies looking to increase efficiency. Since fewer panels are required to get the same amount of efficiency as you would with simple solar modules, this also results in fewer other materials needed for the installation. This includes less racking and wiring and less time spent on the roof overall.  

The Downside of PERC Panels 

One major downside of PERC solar cells, strangely enough, is caused by one of its perks. Since these modules can be manufactured with the same equipment and tools as standard panels and are really just considered a modification or regular panels, PERC cells will often have metal ribbons or strips running through them to attach that extra layer. If this metal rips or cracks, the panels will cease to work correctly and require servicing or a replacement.  

The cost of PERC panels might also turn off a few interested homeowners from selecting them for their solar installations since not everyone may be able to afford this technology upfront. This, however, can be alleviated by the solar installer with financing options, incentives, and discounts.