Researchers at the University of Western Ontario in Canada have proposed a novel solar module encapsulation technology using polycarbonate (PC) to replace traditional ethylene vinyl acetate (EVA) and glass. This innovative approach not only eliminates the need for lamination but also enables easy disassembly, reuse of solar cells, and open-source local manufacturing.
Breakthrough Design: Laminate-Free and Disassemblable
Conventional solar modules typically use EVA as an encapsulant, laminated together with a glass cover sheet. However, this structure makes it difficult to remove the EVA from fragile, high-value solar cells without damage during recycling. To address this challenge, the Western University team demonstrated for the first time a laminate-free solar module design encapsulated with polycarbonate.
"This design specifically enables disassembly and circular-economy reuse of PV – solving one of the largest challenges to recycling standard EVA-glass laminated modules," Joshua M. Pearce, corresponding author of the study, told pv magazine. "The design is completely open-source and thus is available for locally manufacturable PV module production, which contrasts with conventional centralized PV manufacturing. This lowers barriers for community-level fabrication and repair."
Technical Principles and Innovations
In this laminate-free, plastic-encapsulated design, polycarbonate sheets replace traditional glass. A pressure- and heat-based process, combined with a 3D-printed polycarbonate seal, encapsulates the module and holds the cells in place without any EVA. This 3D-printed seal replaces the polyisobutylene (PIB) and silicone commonly used in other laminate-free designs. The seal is fused to the two outer PC sheets by heating the material close to its glass transition temperature and applying pressure. The seal includes an opening for the wires, with its width increased near the wire exit so that excess PC can deform during encapsulation and flow around the wires to improve sealing. After encapsulation, ethyl cyanoacrylate adhesive is applied to close any remaining gaps around the wires.
The research team fabricated single-cell modules using monocrystalline cells supplied by Sunpower for testing. Despite the lack of a laminated structure, the prototypes achieved surprising IP68-equivalent sealing performance, strongly supporting their robustness for field applications.
Performance, Cost, and Circular Economy Advantages
The scientists noted that conventional PV modules typically use 3–4 mm thick glass and EVA layers that together transmit about 95% of incoming light to the solar cell. By comparison, the PC cover tested in the study showed a lower transmissivity of 80.38%. Over a 20-year lifetime, a single-cell module could therefore generate about 102 kWh with a glass cover but only around 86 kWh with the PC cover, resulting in an energy loss of roughly 16 kWh due to reduced light transmission.
However, the PC-based design enables exceptionally easy recovery and reuse of PV cells and other components. This could extend system lifetimes beyond 20 years, as recovered cells could be refurbished, upgraded, or reused in new modules with relatively low additional embodied energy. Initial durability tests also showed promising results, including good mechanical integrity and strong water resistance comparable to an IP68 rating.
According to a preliminary techno-economic analysis, the prototype module can generate 2.12 W under sunny conditions and be produced at a cost of about $3.11/W. This is significantly higher than the current average U.S. module price, although the difference largely reflects the use of retail-priced materials and small-scale fabrication in the study. The researchers said costs could drop substantially if PC were sourced from recycled materials and PV cells were purchased at industrial-scale prices. Under these conditions, scaled production could reach an estimated $0.06–0.30/W, potentially making the design competitive with commercial modules. Distributed manufacturing could further reduce costs by lowering transportation needs and enabling localized production, particularly in regions with abundant recycled plastics.
Future Outlook
"Future work should focus on scaling the design to multi-cell modules, optimizing PC transmissivity, and incorporating impact-resistant materials by moving to a hybrid model," the academics concluded. "Further testing under thermal cycling, damp heat, and prolonged UV exposure is also needed to validate long-term durability."
The new encapsulation technique is presented in "Open-source distributed production of polycarbonate solar photovoltaic modules designed for disassembly," published in the Journal of Cleaner Production.
source：First attempt to build solar modules using polycarbonate encapsulant – pv magazine USA
