What you need to know about PERC solar cells

Join us for Empower on June 5-6! You&#;ll hear from industry experts on everything from what to expect for the rest of , to how AI is affecting the industry, and more. Note: This blog was originally published in . It was updated in January, to reflect the most recent information. If you have any questions, please contact us.

Conventional silicon photovoltaic (PV) cells have long been the standard in the solar industry. But as the technology matures and approaches hard efficiency limits, researchers and manufacturers have started to embrace a relative newcomer &#; the Passivated Emitter and Rear Contact (

For more information, please visit our website.

PERC

) solar cell.

In this article, we&#;ll look at the

core benefits

of PERC solar cells, how they work, how they&#;re made, and even how to sell them. But first, let&#;s get into some background about how conventional solar cells work and what limitations they present.

How standard solar cells work

Traditional solar cells contain two layers of silicon, commonly called &#;n-type&#; and &#;p-type&#; for their negative and positive charge behavior. A solar panel

creates electricity

when sunlight hits the solar cells, knocking electrons loose from the n-type layer as the p-type layer accepts them.

These flowing electrons are what create an electric field &#; and by extension &#; clean solar power for the customer&#;s home or business.

Although this basic design has served the solar industry well, plain PV cells suffer from several

types of efficiency losses

, including:

• Insufficient sunlight capture either due to light reflecting off panel surfaces or because of wires and other components blocking light

• Excessive heat buildup, especially as light hits the back-most surface of the PV cells

• Free electrons being knocked out of alignment due to scattered light refraction

• Electrons recombining with the silicon material on the front and back of the solar cell

Fortunately, some of these efficiency losses can be mitigated with technology. 

For example, adding a front passivation layer can help stop front-side recombination. This strategy also helps to reduce some reflection. To prevent unwanted electrons from moving through the cell and hitting the rear contact, it&#;s possible to add a back surface field layer or place all the wires on the back of the panel during the manufacturing process.

The hardest efficiency losses to manage, however, are excessive PV panel heating and back-side recombination. Because of these limits, the maximum efficiency of standard solar modules

hovers around 20%

in the field.

What are PERC solar panels and how do they work?

First

introduced in

, PERC panels are modified silicon cells that have an

additional

layer on the back. Because this extra layer is reflective, it is able to send unused light back across the n-type and p-type junctions to generate more energy. Better still, this reflective surface also helps to reduce rear recombination and prevent longer wavelengths from becoming heat that would otherwise impair the cell&#;s performance.

Early commercial implementations of PERC technology ran into trouble &#; largely due to increased

light-induced degradation

. But with 

steady improvements over the years, PERC modules have since achieved solar generation efficiencies up to 12% higher than their traditional silicon counterparts.

As a result, solar PV installers are able to

save time

and

reduce costs

when using the newer PERC standard. This is because fewer panels are needed to achieve the same solar power output. Using fewer panels also helps to reduce the amount of

racking

,

wiring

, and

MLPE

devices needed to connect everything together.

For example, even if roof space is not a major concern, it may be possible to save

PERC module production

PERC solar modules are structurally similar to other silicon panels on the market, which is a distinct advantage for manufacturers.

Even though there are additional costs when creating passivation and rear contact capping layers, panel manufacturers are able to reuse existing production equipment with minimal retooling required.

This places PERC manufacturing costs on par with conventional silicon cell production. Although PERC panels remain

slightly

more expensive, these costs are largely offset by the increased efficiency gains &#; which yield higher lifetime utility bill savings and carbon offsets for the end user. And as the technology continues to mature thanks to economies of scale and R&D, PERC cells will likely continue to benefit from even larger efficiency gains and cost reductions moving forward.  

Types of PERC solar modules

Mono PERC cells

Monocrystalline solar cells are cut from a single piece of silicon, making them more efficient than polycrystalline panels. Additional PERC layers can be added to help further increase efficiency rates.

Poly PERC cells

Unlike uniform monocrystalline cells, polycrystalline PERC cells are manufactured using a blend of silicon shards. This mix yields lower efficiencies, but polycrystalline cells are cheaper to manufacture. 

Just like with monocrystalline cells, adding a PERC layer can significantly increase the efficiency of polycrystalline cells without dramatically increasing their manufacturing costs. But because higher solar power output is the industry&#;s Holy Grail, the more efficient monocrystalline PERC cell is the preferred standard for most new PV installations.

Growth in PERC cell production

Global demand for PERC modules skyrocketed in the late s and continues to see steady growth. In , the

PERC solar sales market

was estimated at around $150 billion and is projected to hit $290 billion by .

While PERC cells are undoubtedly the top panel on the market, some

industry experts

theorize that PERC cells may be phased out in the next few years, favoring N-type solar cells due to their &#;superior conversion efficiency.&#;

Pros and cons of PERC solar panels

There&#;s a reason PERC cells are the industry standard &#; they&#;re highly efficient and a much-improved type of PV technology compared to traditional solar panels. However, compared to the new development of N-type cells, there are some disadvantages. Let&#;s review the pros and cons of PERC solar panels.

Pros of PERC solar panels

Recommended article:
Factors to Consider When Choosing a Battery

Goto KINGSUN to know more.

• More efficient compared to conventional silicon solar panels

• Work better in low light and high heat conditions compared to standard solar cells

• Are more affordable than N-type solar panels

Cons of PERC solar panels

• Slightly more expensive compared to conventional silicon panels

• Don&#;t produce as much power compared to N-type cells

• Are more negatively influenced by high temperatures than N-type cells

How offering PERC solar panels can increase solar sales

The main selling point of PERC panels is their efficiency. Because they make better use of space, fewer modules are required to produce the same solar output as a standard silicon panel. For customers who may have space constraints, offering PERC panels is a compelling option. The same case goes for customers who don&#;t get as much direct roof sunlight or customers who live in high-heat areas: PERC cells perform better in these conditions compared to traditional cells.

 

But even if roof real estate or weather conditions aren&#;t factors, it&#;s possible to

save installation time and costs

by using PERC modules. Because PERC cells are more efficient, less panels will need to be installed.

Side-by-side cost comparison: Traditional vs. PERC Solar Panels

Cost will still be a major consideration for many clients. To seal the solar deal, it&#;s easier to outline how PERC solar panels are a better value in the long run, even if they&#;re a larger upfront investment. The table below provides a good visual.

Next steps

A knowledgeable customer is one of our best weapons when selling solar. Make sure your customers have all the information by giving them

Want to learn more about the solar industry?You&#;ll hear from industry experts on everything from what to expect for the rest of , to how AI is affecting the industry, and more.For example, even if roof space is not a major concern, it may be possible to save installation time and costs by using higher efficiency PERC modules. If a site takes 40 standard modules or 38 PERC modules to reach the desired annual production, you&#;re able to reduce the amount of racking, wiring , and MLPE devices needed to connect everything together.A knowledgeable customer is one of our best weapons when selling solar. Make sure your customers have all the information by giving them a free Solar Sales Follow Up Kit . It has all the background a customer needs on the basics of solar, and can help set their mind at ease.

As the world transitions towards renewable energy sources, the demand for solar power has skyrocketed. The solar industry is projected to grow from $253.69 billion in to $436.36 billion by , at a CAGR of 6% (Fortune Business Insights). At the forefront of this growth are two competing solar cell technologies: TOPCon and PERC.

TOPCon (Tunnel Oxide Passivated Contact) and PERC (Passivated Emitter and Rear Cell) are the latest advancements in solar cell design, offering improved efficiency and performance. As homeowners and businesses explore solar panel installations, understanding the key differences between these technologies is crucial for making an informed decision.

This comprehensive guide will delve into the intricacies of TOPCon and PERC solar cells, comparing their efficiency, cost, manufacturing complexity, high-temperature performance, lifespan, and more. By exploring the pros and cons of each technology, as well as real-world performance data from leading manufacturers, you&#;ll gain valuable insights to determine which solution best suits your needs.

What are TOPCon Solar Cells?

TOPCon, short for Tunnel Oxide Passivated Contact, is a cutting-edge solar cell technology that is rapidly gaining prominence in the photovoltaic (PV) industry. This innovative design represents a significant advancement over traditional solar cell architectures, offering enhanced efficiency and performance.

At the core of TOPCon solar cells lies a unique structure that utilizes a thin oxide layer and a polycrystalline silicon layer to create a highly efficient passivated contact. This design allows for improved charge carrier extraction, resulting in higher energy conversion rates. As explained by Renewsys World, TOPCon cells are a type of n-type solar cell, made with a semiconductor material doped with phosphorus, which contributes to their superior performance.

One of the key advantages of TOPCon solar cells is their potential for higher efficiency rates compared to conventional solar cell technologies. According to Solarwatt, TOPCon cells have the potential to become the new standard in the PV industry, offering efficiency levels that can surpass those of the widely adopted Passivated Emitter and Rear Cell (PERC) technology.

What are PERC Solar Cells?

PERC, or Passivated Emitter and Rear Cell, is a technology that improves the efficiency of conventional solar cells. In a PERC solar cell, the rear surface is passivated with a dielectric layer, which reduces recombination losses and reflects unused light back into the cell. This results in an increase in energy generation of about 6-12% compared to standard solar cells (SunPower).

The key advantage of PERC technology is its ability to boost efficiency without significantly increasing manufacturing complexity or cost. PERC cells have become the industry standard for residential and commercial solar panels due to their excellent balance of performance and affordability (Aurora Solar).

Efficiency Comparison: TOPCon vs PERC

One of the key advantages of TOPCon solar cells is their higher efficiency compared to PERC cells. According to SunGold Solar, TOPCon boasts an impressive efficiency rate of 26.1%, while PERC cells have an efficiency of around 22.5%. This higher efficiency translates to more power generation from the same surface area of solar panels.

Real-world testing data backs up the efficiency edge of TOPCon technology. A study by Fraunhofer ISE compared TOPCon and PERC solar products and found that TOPCon modules achieved efficiencies over 25% in mass production, outperforming standard PERC panels. The higher efficiency of TOPCon allows solar arrays to produce more electricity while using less roof or ground space.

Cost and Manufacturing Complexity

When it comes to cost and manufacturing complexity, PERC solar cells have a slight edge over TOPCon technology. The production process for PERC cells is less complex and more established, which translates to lower upfront costs. According to an analysis by Eltel Networks, the manufacturing costs for PERC cells are approximately 10-15% lower than TOPCon cells.

However, it&#;s important to consider the lifecycle costs as well. While TOPCon cells have a higher initial cost due to their more complex production process, their increased efficiency can lead to lower levelized cost of electricity (LCOE) over the lifetime of the solar panel. Canadian Solar reports that TOPCon modules can offer over 3% additional electricity generation compared to PERC, which can offset the higher upfront cost in the long run.

Performance in Hot Climates

One of the key advantages of TOPCon solar cells is their superior performance in hot weather conditions compared to PERC cells. According to a study by RenewSysWorld (https://www.renewsysworld.com/post/why-topcon-solar-panels-outperform-mono-perc-multi-in-hot-weather), TOPCon panels can maintain higher efficiencies at elevated temperatures due to their unique cell structure.

PERC solar cells, on the other hand, tend to experience more significant efficiency losses as temperatures rise. While PERC panels still perform reasonably well in hot climates, their output can degrade by 3-5% or more when operating above 25°C (77°F). This makes TOPCon a better choice for installations in regions with extended periods of high temperatures.

In addition to better heat tolerance, TOPCon cells also exhibit lower annual degradation rates compared to PERC. Industry estimates suggest TOPCon degrades at around 0.25% per year, while PERC cells may degrade 0.5-0.7% annually. Over the 25-30 year lifespan of a solar panel, this can result in a notable difference in total energy output favoring TOPCon.

Lifespan and Degradation Rates

Both TOPCon and PERC solar cells are designed for long operational lifespans, typically warranted for 25-30 years by manufacturers. However, their degradation rates over time can differ. A study by pv-magazine found that TOPCon modules should not exhibit higher degradation levels than leading PERC modules over a 30-year lifetime.

In general, solar panels experience an annual degradation rate of around 0.5% under ideal conditions, according to SolarMagazine. However, factors like high temperatures, humidity, and poor maintenance can accelerate degradation. While TOPCon cells may degrade slightly faster initially, their long-term degradation rates are expected to be comparable to PERC over a 25-30 year lifespan.

Pros and Cons of TOPCon Solar Cells

TOPCon solar cells offer several key advantages over traditional solar cell technologies:

Advantages:

• • Higher efficiency ratings, typically 22-24% compared to 19-22% for PERC cells, resulting in more power output per square foot. (Source)

• • Lower temperature coefficients, meaning better performance in hot climates. TOPCon cells degrade less at higher temperatures.

• • Simpler structure and manufacturing process compared to other high-efficiency cell technologies like HJT or IBC.

Disadvantages:

• • Higher upfront costs due to advanced materials and more complex production compared to standard PERC cells. (Source)

• • Relatively new technology with less long-term field data on reliability and degradation rates over 25+ years.

• • Manufacturing complexity is still higher than for standard PERC cells, requiring more process steps. (Source)

Pros and Cons of PERC Solar Cells

PERC (Passivated Emitter and Rear Cell) solar cell technology offers several advantages over traditional crystalline silicon cells, but also has some potential drawbacks to consider:

Pros:

• • Higher efficiency, typically 1-2% more than standard cells due to improved light capture and reduced recombination losses. This translates to more power output from each solar panel. (Source)

• • Better high-temperature performance and reduced efficiency losses in hot climates, thanks to the rear passivation layer reflecting more infrared light. (Source)

• • More affordable than premium high-efficiency cell technologies like heterojunction or IBC cells.

Cons:

• • Slightly more complex manufacturing process than standard cells, though still simpler than most premium high-efficiency options.

• • Potential for higher initial light-induced degradation (LID), though this is mitigated in modern PERC cells. (Source)

• • Lower efficiency potential compared to emerging next-generation cell architectures like TOPCon, HJT, and IBC.

Optimal Applications for Each Technology

When it comes to choosing between TOPCon and PERC solar cells, the optimal application depends on your specific needs and priorities. TOPCon solar cells excel in situations where maximizing energy efficiency is the top concern, such as residential installations with limited roof space or commercial projects aiming to generate the highest possible output.

According to Rayzon Solar, TOPCon cells generally offer higher efficiency rates than PERC cells due to their advanced passivation technology and superior temperature performance. This makes them an attractive choice for hot climates or installations where space constraints necessitate squeezing every available watt out of the available surface area.

On the other hand, PERC solar cells strike a balance between cost and performance, making them a compelling option for larger-scale utility projects or installations where budget is a significant factor. While not as efficient as TOPCon, PERC cells offer a more cost-effective solution for generating substantial amounts of clean energy without breaking the bank.

Real-World Performance Comparisons

When it comes to real-world performance, lab tests and field data from top solar panel manufacturers provide valuable insights. According to Clean Energy Reviews, TOPCon solar panels from SunPower and LG have demonstrated superior efficiency and energy yield compared to conventional PERC panels in controlled testing environments.

SunPower&#;s Maxeon 7 TOPCon panels, for instance, achieved an impressive 22.8% efficiency rating under standard test conditions, outperforming most PERC panels on the market. LG&#;s NeON R series, another TOPCon offering, has also consistently ranked among the highest-performing solar panels in third-party tests conducted by organizations like the Photovoltaic Evolution Lab (PVEL).

In real-world field tests, TOPCon panels have proven their mettle, particularly in hot and sunny climates. Data from Panasonic&#;s TOPCon modules installed in Arizona showed a mere 2% degradation after four years of operation, highlighting their exceptional resistance to high temperatures and long-term reliability.

The Future of TOPCon vs PERC Solar Cells

As the solar industry continues to evolve, the battle between TOPCon and PERC solar cell technologies is expected to intensify. According to industry analysts, TOPCon technology is poised to become the dominant player in the market as its costs fall below those of mono-PERC cells.

The National Renewable Energy Laboratory&#;s (NREL) Spring Solar Industry Update projects that while PERC will still hold a 50% market share in , its dominance will wane as TOPCon and other high-efficiency cell designs gain ground. Module efficiencies are expected to rise across all technologies, with TOPCon leading the charge.

The International Energy Agency (IEA) also notes the expanding dominance of PERC with almost 60% market share, but highlights the emergence of TOPCon and other new, even higher-efficiency cell designs. As the demand for high-performance and cost-effective solar solutions continues to grow, the industry is likely to see a shift towards these next-generation technologies.

Which is Right for You?

When deciding between TOPCon and PERC solar panels, there are several key factors to consider for homeowners and businesses:

For homeowners prioritizing maximum energy production and efficiency, TOPCon panels may be the better choice. Their higher efficiency ratings (up to 1% higher than PERC) can translate to more electricity generated from the same roof space. However, this increased performance comes at a higher upfront cost.

For businesses focused on balancing cost and performance, PERC panels offer an excellent middle ground. While not as efficient as TOPCon, PERC technology is more affordable while still providing solid energy output and reliability. PERC may be preferred for large commercial installations where upfront costs are a major consideration.

If you live in a hot climate region, TOPCon&#;s better temperature coefficient gives it an advantage, as it can maintain higher production levels versus PERC in extreme heat. For cooler regions, this benefit diminishes.

Ultimately, your decision should weigh factors like your budget, expected solar production needs, local climate patterns, and projected payback timelines. An experienced solar installer can guide you through analyzing these variables for your specific situation.

Conclusion

TOPCon cells offer superior efficiency and performance, making them an excellent choice for maximizing energy production, especially in residential installations where space is limited. However, PERC cells strike a great balance between cost and performance, often being the more cost-effective option for larger commercial or utility-scale projects.

Ultimately, the decision between TOPCon and PERC will depend on your specific needs and priorities. If maximizing energy output and long-term performance is the primary concern, TOPCon panels are the way to go, despite their slightly higher upfront cost. For those on a tighter budget or with ample space for a larger installation, PERC panels offer a compelling mix of efficiency and affordability.

As solar technology continues to evolve, it&#;s likely that TOPCon cells will become more dominant in the long run, thanks to their superior efficiency and potential for further advancements. However, PERC cells will remain a strong contender, especially as manufacturers continue to refine and optimize the technology.

Regardless of which technology you choose, investing in high-quality solar panels from reputable manufacturers is crucial for ensuring optimal performance, reliability, and a strong return on investment. By carefully weighing the pros and cons of TOPCon and PERC, you can make an informed decision that aligns with your energy needs, budget, and long-term sustainability goals. Contact Solar N Plus if you need topcon cells or PERC cells solutions.

For more PERC PV Moduleinformation, please contact us. We will provide professional answers.