JA Solar’s CTO Dr. Zi Ouyang Elaborated on the Advantages of TOPCon Technology and its Future

On August 16, JA Solar's CTO Dr. Zi Ouyang discussed the numerous advantages of TOPCon technology, highlighting its enhanced efficiency, superior performance and future potential within the PV industry, in the 2024 TOPCon Solar Cell Technology Development Trend Seminar. With ongoing innovations and a commitment to sustainability, TOPCon technology is poised to play a pivotal role in advancing solar energy solutions globally, setting new standards in both energy yield and cost-effectiveness.

The participants of the seminar unanimously agreed that TOPCon will be the mainstream technology for the next five years. Heterojunction ("HJT") and back contact ("BC") technologies also get significant attention but still require process maturity and cost reduction.According to InfoLink Consulting, overall production capacity (including capacity under construction) is expected to approach 900GW, which is sufficient to meet most of the market demand for the next five years. Meanwhile, the report predicts that TOPCon technology market share will remain at 70%-80% for the next five years.

JA Solar's CTO Dr. Zi Ouyang elaborated on the two main reasons that make TOPCon the mainstream technology. The key factor to be considered in cell design is the balance between light absorption, passivation, and multi-particle transmission. TOPCon's combination of contact passivation with poly is the best technical approach to be applied in mass production so far.

Furthermore, the development of mass production technology in PV is an integration of "process + equipment + materials." From PERC to TOPCon, the cost of upgrading the manufacturing process and equipment is less than 30%, yet can greatly improve conversion efficiency, offering exceptional cost-effectiveness. The rapid development of TOPCon was natural after key technology challenges such as boron expansion and poly deposition were overcome, making TOPCon the preferred choice for leading manufacturers.

There is now an industry consensus that TOPCon technology will hold a mainstream position for the next five years or so. TOPCon technology is not static. The introduction of new equipment and new materials and the optimization of cell structure could all help improve the cell efficiency. For example, metallization plays an important role as a key step in the cell to module link. As a product manufactured at high temperatures, a TOPCon cell is feasible for more metallization paths than heterojunction cells and thus has greater potential for innovation and efficiency improvements.

Compared with BC, TOPCon is more suitable as the bottom cell in tandem cells. Many believe that the "TOPCon+perovskite" tandem cell may lead the industry into a multiyear era of "30%+" efficiency in mass production.

In July this year, in the "Solar Cell Efficiency Tables (version 64)" which is compiled by UNSW, JRC, AIST, NREL, ISFH and Fraunhofer, JA Solar topped the "Large-area n-type TOPCon Cell Efficiency" with its mass production cell size, setting a new world record.

In August, ISFH updated the efficiency certification of mass-produced size cell efficiency, which is included in the "2024 China's Highest Efficiency Solar Cell" by the PV Committee of the China Renewable Energy Society. The breakthrough in mass-produced solar cell size is one of the biggest challenges facing the industry. With continual breakthroughs in this area, JA Solar is proving both its strength in technology research and development and the potential of TOPCon technology.

TOPCon technology is advantageous across a wide range of applications. With the rapid development of global PV market, more diversified products are needed for different application scenarios. With the advantages of high efficiency and low cost brought by high capacity production, and its feasibility for different applications, TOPCon products are increasingly preferred by producers and users. For JA Solar, different TOPCon products are being developed for different installation environments, such as deserts, tropical, plateaus, and extreme cold. JA Solar also provides customized TOPCon products for pile and floating offshore PV solutions, single glass and anti-dust rooftop PV, and anti-glare solutions that meet diverse market needs.