Technological advancements in solar cell technology have played a pivotal role in improving the efficiency and cost-effectiveness of solar energy. With the PERC cell having reached its limits, one such innovation that has gained significant attention in recent years is TOPCon (Tunnel Oxide Passivated Contact) cell technology.
In this blog post, we will explore what TOPCon cell technology is, its advantages over PERC cells, and its current and projected market share.
Benefits of TOPCon Technology
Some notable benefits of this new cell technology include:
Adaptability to the existing manufacturing process
One of the key benefits of TOPCon cells lies in their seamless integration with the current manufacturing infrastructure. As TOPCon cells can be produced using similar equipment as PERC cells, the transition to this new technology from existing PERC production lines is smooth and cost-effective. A slight increase in cost allows for easy upgrading to TOPCon solar cells, making it a viable and efficient option for manufacturers.
Higher efficiency
TOPCon cells reach an efficiency of around 28%, which is significantly higher than the efficiency of PERC cells, which is typically around 22%.
Enhanced low-light performance
TOPCon cells exhibit higher efficiency in low-light conditions, enabling them to generate electricity even when sunlight is limited.
Better performance in a hot climate
TOPCon panels have a lower temperature coefficient, usually < (-)0.30 %/°C. This results in less power reduction with every degree rise in temperature, allowing TOPCon panels to outperform mono PERC panels in hot climates by generating more power.
Increased energy generation
When compared to PERC modules, TOPCon modules demonstrate significantly lower power degradation both within the first year and over their extended 25 to 30-year lifespan. As a result, TOPCon panels consistently produce more energy throughout their operational lifetime.
Improved bifaciality
TOPCon cells have a higher bifaciality than PERC cells, generally 80-85%, which means they can generate more electricity from the rear side of the cell. This is important for solar panels that are installed in bifacial configurations.
What is TOPCon Solar Cell Technology?
TOPCon cells are a type of n-type solar cell. N-type cells are made with a semiconductor material that has been doped with phosphorus, which gives the material a negative charge. This type of cell has several advantages over p-type cells, including higher efficiency and better performance in low-light conditions.
TOPCon cell technology is a further development of PERC technology. In PERC cells, the rear surface of the solar cell is passivated with a thin layer of aluminium oxide (Al2O3). This layer helps to reduce recombination losses, which can improve the efficiency of the cell.
In TOPCon cells, a thin layer of silicon dioxide (SiO2) is deposited on top of the Al2O3 layer. This layer creates a tunnelling junction, which allows electrons to flow more easily from the p-type emitter to the n-type substrate. This tunnelling junction helps improve the efficiency of the cell by reducing the series resistance.
TOPCon cells are generally n-type. N-type cells are made with a semiconductor material that has been doped with phosphorus, which gives the material a negative charge. This type of cell has several advantages over p-type cells, including higher efficiency and better performance in low-light conditions.
Current and Estimated Market Share
Currently, TOPCon cells hold a relatively small market share, but it is growing rapidly. In 2022, TOPCon cells accounted for about 10% of the global solar cell market. However, TOPCon is expected to become the dominant cell concept after 2025 and is estimated to reach a market share of around 60% by 2033, according to the International Technology Roadmap for Photovoltaic (ITRPV), April 2023 edition.
Data credits:
RenewSys R&D
International Technology Roadmap for Photovoltaic (ITRPV), April 2023 edition
Image credits:
RenewSys