en.Wedoany.com Reported - On July 29, the 2026 4th DeCarbon International Conference on Low-Carbon Science and the 3rd Solar Cell Materials and Devices Academic Salon were grandly held in Qingdao, Shandong Province. Dr. Wu Lin, Senior R&D Engineer at Tongwei's Photovoltaic Technology Center, was invited to attend and delivered a keynote speech, sharing Tongwei's industrialization pathway in perovskite-silicon tandem solar cells, breakthroughs in key technologies, and in-depth reflections on common scientific challenges facing the industry.

Industry Breakthrough: Tandem Technology Is a Must-Choose

At the forum, Dr. Wu Lin pointed out in his keynote speech titled "Several Scientific Issues in the Industrialization Development of Perovskite-Silicon Tandem Solar Cells" that while the cost of photovoltaic power station systems has been declining year by year, land and labor costs are rising, and the industry faces severe homogenization. Crystalline silicon cell efficiency has reached 28%, approaching the theoretical limit, leaving limited room for cost reduction through cell-level improvements alone. Perovskite-silicon two-terminal tandem cells have a theoretical efficiency of nearly 45%, with laboratory PCE already exceeding 35%, and can effectively leverage the mature crystalline silicon industry, making them a core direction for cost reduction and efficiency enhancement. Currently, megawatt-scale pilot lines for perovskite tandem cells have begun trial production, significantly accelerating the industrialization process.

Tongwei's Approach: Compatible with HJT Production Lines

Tongwei has chosen a technical route featuring commercial HJT silicon wafers for the bottom cell and a two-step perovskite film formation method for the top cell, which is highly compatible with existing crystalline silicon production lines. The manufacturing process requires no glove boxes, no toxic solvents, and no atmosphere control, demonstrating significant mass-production feasibility.

In the large-scale preparation of perovskite absorber layers, Tongwei has proposed a novel perovskite crystallization process that regulates the dynamic balance between perovskite nucleation and ion migration, resolving the challenge of achieving conformality, crystallinity, and compositional uniformity simultaneously in perovskite films deposited on textured substrates. Additionally, based on a low-edge-loss solution coating technique, uniform perovskite film formation on 210-size substrates has been achieved, systematically overcoming the industrialization bottleneck of the two-step perovskite reaction.

Landmark Achievement: 32.19% Efficiency on Full-Size 210 Half-Cells

In terms of industrialization results, in September 2025, Tongwei built the industry's first 5MW tandem cell pilot line. Leveraging the high-quality perovskite absorber layer large-scale preparation technology developed on this pilot line, the full-area conversion efficiency of 210 half-cells reached 32.19%, and the power output of G12N-66 standard-format modules exceeded 776W. In March 2026, Chinese Premier Li Qiang personally visited Tongwei's perovskite pilot line for inspection, fully reflecting the nation's high regard for this cutting-edge technology direction.

Dr. Wu Lin stated that the photovoltaic industry is still undergoing deep adjustment, and tandem technology will not see large-scale explosive growth in the short term. At this stage, it is essential to strengthen internal capabilities and systematically address systemic issues such as device efficiency at commercial sizes, scalable manufacturing, and reliability. Tongwei will continue to advance cutting-edge technologies including silver-free metallization, ultra-low-temperature interconnection, and 0BB, accelerating the commercialization of perovskite-silicon tandem solar cells.

As a global leader in photovoltaics, Tongwei has always driven industrial upgrading through technological innovation. This exchange event not only showcased Tongwei's deep expertise in tandem cell technology but also provided a "Tongwei Solution" for industry mass production, highlighting the leading role of Chinese photovoltaic enterprises in next-generation technologies and contributing Tongwei's strength to the global energy transition.