Oxford PV, a perovskite solar module manufacturer, has achieved a significant milestone in the development of perovskite-silicon tandem solar modules. They have successfully integrated their perovskite-silicon tandem solar cells with Fraunhofer ISE's Matrix Shingle module technology, resulting in a power conversion efficiency of 25.6%. This achievement is a testament to the potential of combining two high-tech approaches from Europe, as noted by Stefan Glunz, head of photovoltaics at Fraunhofer ISE.
The Matrix Shingle approach, developed by Fraunhofer ISE, offers a unique solution to conventional solar module interconnection. By replacing traditional busbar-and-ribbon architectures with a dense, overlapping cell layout, it reduces resistive and shading losses while improving energy yield, durability, and module-level performance. This innovative design involves precision-cutting photovoltaic cells into narrow strips and reconfiguring them into a shingled pattern, similar to roof tiles. The adjacent strips overlap slightly and are bonded using electrically conductive adhesive (ECA), providing both mechanical adhesion and electrical interconnection.
One of the key advantages of this approach is the elimination of soldered interconnect ribbons and busbars, which reduces inactive spacing that would otherwise block incoming light. As a result, optical shading losses are significantly reduced, and a larger fraction of the module surface becomes active photovoltaic area, improving packing density. The reduction in metallization shading also enhances current collection efficiency, as more of the cell surface is exposed to sunlight.
Additionally, the shingle configuration shortens current pathways and distributes current more uniformly across the module, which can reduce resistive losses and localized heating. The use of ECA instead of high-temperature soldering also reduces thermal stress during assembly, helping to preserve cell integrity and potentially improve long-term reliability. Overall, the Matrix shingle approach increases module power density by combining higher active-area utilization with improved electrical and optical performance.
Oxford PV's CTO, Ed Crossland, highlighted the successful integration of their perovskite-silicon tandem solar cells with Fraunhofer ISE's Matrix Shingle module technology. This combination not only achieves efficiency gains but also reduces resistive losses, removes the need for copper interconnects, and improves resilience under partial shading. Crossland also noted that the module presented is a prototype, built using standard production cells and fully compatible with mass production.
This achievement builds upon Oxford PV's previous milestones. In June 2024, they unveiled their first perovskite-silicon tandem solar module with 26.9% efficiency. A few months later, they announced the commercial launch of perovskite-silicon tandem modules in the United States. Oxford PV began working on their perovskite tandem solar modules in 2014 and claims to have a clear roadmap to bring the technology to over 30% efficiency.
In conclusion, Oxford PV's achievement of 25.6% efficiency in their perovskite-silicon tandem module, combined with Fraunhofer ISE's Matrix Shingle technology, demonstrates the potential for significant advancements in solar energy conversion. This development paves the way for more efficient and cost-effective solar modules, contributing to the global transition towards renewable energy sources.
