PERC technology is exerting pressure on the traditional solar cell supply chain as a result of strong global demand for higher-efficiency modules. Technologies like HJT and IBC, categorized under PERC, are anticipated to gain market share starting from 2017.
By 2020, PERC is expected to become a mainstream technology, holding a leading position among emerging technologies. Top cell manufacturers are increasingly adopting PERC, either by upgrading existing in-cell lines or placing orders for new PERC lines.
What exactly are PERC solar panels?
PERC can stand for either Passivated Emitter and Rear Cell or Passivated Emitter and Rear Contact. Essentially, a PERC solar cell is a more efficient version, enabling solar panels constructed with PERC panels to more effectively convert sunlight into usable electricity.
Solar panels in Brisbane that utilize PERC solar panels generally outperform traditional panels in various conditions, including low-light situations and high temperatures. PERC technology enhances efficiency by incorporating an additional layer to the back of a conventional solar cell, providing several production-related advantages to the cell.
How do PERC solar panels differ from standard solar panels?
In terms of construction, a PERC solar cell is not significantly different from a typical photovoltaic solar cell. Both types of solar technology utilize silicon wafers to generate a flow of electrons from incoming solar radiation, and their overall construction is very similar.
The primary distinction between PERC panels and typical monocrystalline photovoltaic panels lies in the integration of a back surface passivation layer. This layer, situated on the back of the panels, offers three key benefits that enhance cell efficiency.
How does the inclusion of a back surface passivation layer contribute to improvements in solar cell efficiency? The passivation layer in a PERC solar cell enhances overall efficiency in three key ways:
- Light Reflection Back Through the Cell
The back surface passivation layer reflects light that traverses the silicon cell without being absorbed, redirecting it back for a second absorption attempt. This reflection ensures that a greater portion of incoming solar radiation is absorbed by the silicon cell, thereby enhancing the cell’s efficiency.
- Minimized Electron Recombination
Introducing a back surface passivation layer diminishes “electron recombination” within the solar cell. In simpler terms, electron recombination refers to the tendency of electrons to recombine, impeding the free movement of electrons through the solar cell. By reducing electron recombination, PERC solar cells aim to optimize efficiency.
- Reduced Absorption of Heat
The third advantage of a PERC solar cell lies in the reflection of specific light wavelengths. Silicon wafers in solar cells can only absorb light up to 1180 nanometers (nm), and light waves with higher wavelengths pass through the silicon, getting absorbed by the metal back sheet of the solar panel, generating heat.
Elevated temperatures lead to reduced operational efficiencies in solar cells. The back surface passivation layer in PERC solar cells is meticulously designed to reflect light with a wavelength exceeding 1180 nm, thus mitigating the heat absorbed by the solar cell and consequently elevating overall efficiency.
Mono PERC panels find application in rooftop solar systems due to their exceptional efficiency. Despite being pricier compared to other solar panel types, mono PERC panels are well-suited for both residential and commercial rooftop solar installations.
Monocrystalline cells (Mono) are crafted from single silicon crystals, offering high efficiency, superior performance in low light conditions, and an extended lifespan due to their use of high-quality silicon crystals.
On the other hand, Polycrystalline cells (Poly), as the name suggests, are formed by melting multiple silicon crystals. They are known for being easy to manufacture, cost-effective, and generating less waste. Nevertheless, the rapidly evolving landscape of cell manufacturing processes is beginning to narrow the cost advantage that poly modules once held over their mono counterparts.
What are the benefits of utilizing mono PERC panels?
While both types of panels serve the same purpose of harnessing energy from sunlight, there are technical distinctions between mono PERC and polycrystalline panels. Mono PERC panels exhibit a 2% to 2.5% higher efficiency compared to their polycrystalline counterparts.
They also demonstrate better performance in low-light conditions and high temperatures. Mono PERC panels typically come in wattages of 370W and above, whereas polycrystalline panels typically reach up to 300W. The installation of mono panels allows for a more efficient utilization of roof space.
As of 2018, mono modules constitute 50% of global PV cell production. While there are other cell developments such as bifacial and thin film, the former is relatively new, and the latter exhibits lower efficiency, especially for residential applications.
PERC, as an innovation, is currently available in the form of both mono and poly cells. Traditional solar cells typically have an emitter layer on the front surface and a black coating on the rear side. In contrast, Passivated Emitter and Rear Cell (PERC) technology incorporate a dielectric passivation film on the rear surface of cells.
This design allows the front surface to absorb direct sunlight, while the rear surface captures scattered or reflected light. As a result, PERC cells achieve higher energy generation compared to their traditional counterparts, owing to enhanced light absorption and internal reflectivity. These advantages are particularly beneficial for end-users, especially residential consumers.
Manufacturing PERC Solar Cells
A significant advantage of PERC technology lies in the minimal investment required for manufacturing PERC solar cells compared to standard monocrystalline solar cells. To produce a PERC cell, two additional manufacturing steps are necessary:
- Application of the back surface passivation layer
- Laser/chemical etching to create small pockets in the passivation layer
These two steps do not significantly increase the costs of the solar cell manufacturing process but result in a higher-quality, more energy-dense solar cell. The conventional obstacle to adopting new solar cell technology often revolves around the high costs associated with new equipment production. However, transitioning to PERC solar cells entails minimal monetary investment, offering an upgraded product at a lower cost.
Advantages of PERC Technology for Solar Consumers
Solar panels constructed with PERC technology enable more energy-dense solar installations. This means that the same amount of energy can be generated with fewer PERC solar panels compared to standard ones. Consequently, by requiring fewer solar panels for your installation, overall costs can be reduced.
Moreover, having fewer panels provides greater flexibility in positioning them on your roof. If available roof space is limited, the use of PERC solar panels or any high-efficiency panel product can transform a solar installation that meets your power needs into a practical reality.
Lowering the quantity of required solar panels also has the advantage of reducing the balance-of-system (BOS) costs associated with your solar panel installation. BOS costs typically encompass any expenses related to solar installation components other than the solar modules themselves. Inverters, racking, and wiring are all contributors to BOS costs, and the fewer panels needed, the fewer additional components will be required.
Top Mono PERC Solar Panels in Australia
While Mono PERC may not be the ideal choice for every solar project, it proves highly suitable for residential rooftop installations, driven by the desire for a quicker return on investment and reduced installation costs. The growing demand for high-efficiency panels is compelling consumers to increasingly embrace the use of mono PERC panels.