HJT modules continue to rely on glass-glass encapsulation due to their high sensitivity to moisture and UV, which current backsheet solutions can't adequately protect against
With HJT's limited market share and specific material challenges, backsheet R&D is largely centered on TOPCon, where compatibility and performance are more achievable
Coveme’s use of rPET in backsheets – with up to 33% recycled content – maintains virgin material quality while reducing environmental impact through chemical recycling
Endurans develops recyclable polyolefin encapsulants with low carbon intensity and high monomer recovery potential, aligning with clean energy policies and circular economy goals.
The TaiyangNews Market Survey on Backsheets and Encapsulation 2025 explored solutions for both backsheets and encapsulation across various solar technologies. As we have discussed in our previous articles focusing on backsheet options for TOPCon, the natural follow-up question is: what is the optimal solution for encapsulation?
HJT: The backsheet-based solution is currently not a priority for HJT – first, due to its limited market share and high R&D costs. No new technology or materials have yet succeeded in sufficiently lowering WVTR for HJT cells. For now, glass-glass solutions are the primary approach for HJT, as WVTR challenges make backsheet-based solutions less viable. While companies like Meyer Burger and REC have produced HJT modules with glass backsheets, newer HJT cells are more sensitive to moisture and UV exposure, according to leading backsheet suppliers. The advanced surface treatments and metal compositions of these cells further distinguish them from older technologies, likely making glass-backsheet configurations less viable for future HJT modules (see Transparent Backsheets For TOPCon).
Sustainability: As the solar industry continues to expand, sustainability has become a critical focus, ensuring that the environmental benefits of solar energy extend beyond power generation to the entire lifecycle of PV modules. With growing concerns over waste management and resource conservation, manufacturers are exploring ecofriendly materials that reduce carbon footprints and enhance recyclability. One such advancement is the use of recycled PET (rPET) in backsheet production. Coveme took the first step of developing a backsheet with 33% recycled content. As also detailed in our previous edition of the survey, the process breaks down waste material to the starting monomer – the building block for all polyesters – removes contamination, and then rebuilds it into a PET film for PV or any other application.
Coveme offers products containing PET films made using a blend of upcycled PET waste with 2/3rd virgin material. The key here is to make the recycled product’s properties identical to one made with 100% virgin material. Endurans is yet another company taking sustainability seriously, designing its polyolefin backsheets and encapsulants with recyclability, low carbon intensity, and efficient waste-to-energy recovery in mind. Polyolefins, being thermoplastic materials, are ideal for recycling as they can be melted down and reprocessed at the end of a module’s life cycle. Additionally, they enable potential pyrolysis, a process that can recover monomers with up to 90% efficiency, thereby supporting circular economy goals in the solar industry. Compared to traditional materials, polyolefin-based products offer a lower carbon footprint, contributing to the industry’s broader sustainability objectives. Endurans is also actively developing a pipeline of new products within the polyolefin and encapsulant categories to meet evolving regulatory requirements and sustainability standards. These innovations align with the objectives of the Inflation Reduction Act (IRA) and support the growing demand for US-manufactured solar products (see Coveme's Italian-Engineered PV Backsheets Featured At REI 2024).
As India ramps up efforts to strengthen its solar PV manufacturing industry, the TaiyangNews Solar Technology Conference India 2025 will serve as a key platform for discussing the latest technological advancements. Scheduled for April 10–11, 2025, in New Delhi, the event will bring together technologists, scientists, and engineers driving innovation in the sector.
Day 2 will feature a session titled "Advancing Solar Module Performance and Reliability Through the Right Bill of Materials." Speakers include InYoung Suh, Director of Business Development at Hangzhou First; Dr. Khushbu Patel, AGM of Business Development at Alishan Green Energy, who will discuss innovations in encapsulants and backsheet materials; and Mohammad Asif Patel, General Manager – BD at DhaSh PV Technologies, who will present on "From Concept to Connection: Experiences in Setting Up a GW-Scale JB Fab in India." Registrations are open here.
The text is an excerpt from the latest TaiyangNews Market Survey on Backsheets & Encapsulation Materials 2024/25, which can be downloaded for free here.