As the global energy transition enters a critical phase, the rise of Heterojunction (HJT) technology is undoubtedly at the heart of a new technological revolution and market transformation. On September 6th, the 2024 HJT Heterojunction & Tandem Industry Summit and the 6th Roundtable of the Chinese Photovoltaic 740W+ High-Efficiency Club, was held in Pudong, Shanghai. Grand Sunergy’s CEO, Gao Fei, was invited to deliver the opening speech, and CTO Zhang Wenbin gave a keynote presentation.
Accelerating Photovoltaic Disruption with Tandem Perovskite
The photovoltaic (PV) industry is undergoing a period of profound adjustment, characterized by a temporary imbalance in market supply and demand, sharp price fluctuations, and accelerated technological iterations, all of which test the wisdom and decisiveness of industry professionals. As a next-generation high-efficiency cell technology, HJT boasts leading conversion efficiency, superior power generation performance, and exceptional growth potential. Its maximum power and conversion efficiency continue to set new records, with the industry’s average cell production efficiency already exceeding 26%. With the addition of tandem perovskite, efficiency is expected to surpass 30%.
In recent years, as the HJT equipment and materials supply chain has gradually improved, and the localization of equipment and process compatibility has advanced, the cost-reduction and efficiency-increase process of HJT has accelerated further. Gao Fei stated, “After more than 30 years of development, HJT still has high growth potential. Heterojunction combined with perovskite cells is currently transitioning from the laboratory to pilot production and mass production. By 2025, HJT’s tandem technology will bring more surprises to the market.”
Regarding market applications, HJT technology is steadily aligning with market demand, fully exploring the characteristics of various products, and expanding application scenarios with precision and specialization. “Particularly in terms of market feedback, the acceptance of HJT is steadily increasing,” Gao Fei said. “We are seeing more and more state-owned enterprises and central enterprises include HJT in their bidding processes with dedicated sections, demonstrating that the potential of this technology is being widely recognized.”
“Nowadays, an increasing number of PV companies are entering the HJT industry, from equipment and key auxiliary materials to end-use applications. A relatively complete industrial ecosystem is gradually taking shape. We believe that HJT’s long-term development is not a one-company effort but requires collaborative innovation across the entire industrial chain. It involves building a full-dimensional ecosystem encompassing production, academia, research, and financial capital. We need to transform technological advantages into market advantages, turn research achievements into commercial value, and make HJT a new and vital productivity force in the photovoltaic technology landscape.”
High-Power HJT Enters the 740W+ Era
During the keynote session, Zhang Wenbin delivered a presentation titled Achieving Mass Production of 740W+ HJT Modules. In terms of efficiency improvement, Zhang stated, “HJT has far from reached its efficiency bottleneck. Through developments such as steel plate printing, ACP surface texturing, silicon wafer back polishing, high-mobility target materials, silver-copper paste, and 0BB (zero-busbar) technology, HJT’s mass production efficiency is expected to increase by 0.4% to 0.6% annually. By Q1 2025, the cell mass production efficiency is expected to reach 26.8%. With the introduction of 0BB technology, the module mass production power is expected to reach 740W by Q1 2025.”
Supported by its New Energy Research Institute, Grand Sunergy officially launched its Expedition Series (210R) and Seapower Series (210), which are suitable for offshore photovoltaic applications, in June of this year. These products not only inherit HJT’s natural advantages of high conversion efficiency and superior power generation performance but also achieve a good balance between performance and cost through measures like using ultra-thin silicon wafers, silver-coated copper, and 0BB to reduce costs. With the gradual implementation of clear cost-reduction and efficiency-improvement pathways such as steel plate printing, ACP surface texturing, and back polishing, HJT will achieve unprecedented technological breakthroughs.
Scenario-driven innovation is key to promoting photovoltaics as a major energy source in new power systems. “Photovoltaics + desert reclamation,” “photovoltaics + agriculture, fishing, and livestock,” “photovoltaics + transportation,” and “photovoltaics + architecture” are all multi-energy complementary models that have long received policy support from top-level designs. Zhang Wenbin introduced that Grand Sunergy, while maintaining high power and high reliability, has developed targeted module packaging technologies for specific environments like oceans and deserts to address weather resistance challenges and expand heterojunction product applications.
Taking offshore photovoltaic applications as an example, Grand Sunergy uses solutions like double-layer coated glass, UV-resistant glue film, high-water-resistance butyl rubber edge sealing, polymer composite frames, waterproof/salt-spray-resistant junction boxes, connectors, dust plugs, and protective covers to comprehensively address the technical challenges of offshore PV applications. Due to the high investment costs of offshore photovoltaic projects, especially in terms of fixed support structures, pile foundations, and PV area construction, the cost of offshore fixed-pile foundations is about twice that of land-based ones. However, with HJT’s high reliability, weather resistance, and power generation performance, it helps spread system costs, making it more suitable for high-development-cost projects like offshore photovoltaic installations, thereby maximizing investment returns.
Zhang Wenbin emphasized that technological innovation is the fundamental driving force for breaking the boundaries of photovoltaic application scenarios. “We will continue to strengthen core technology development, improve product performance and service quality, and accelerate all-weather, multi-scenario innovation to support more efficient HJT photovoltaic projects.”
