A research team from Fraunhofer Institute for Solar Energy Systems ISE has developed a groundbreaking photovoltaic (PV) module utilizing perovskite silicon tandem solar cells from Oxford PV. This module boasts an impressive efficiency of 25% and yields 421 watts over 1.68 square meters, marking it as the world's most efficient silicon perovskite tandem solar module in industrial format. Leveraging existing mass production equipment and optimized processes at Fraunhofer ISE's Module-TEC, this innovation holds promise for significantly enhancing solar energy generation efficiency.

Oxford PV, stemming from Oxford University, is advancing perovskite-silicon solar cells with a significant milestone: producing cells in M6 format with an impressive efficiency of 26.8% at its Brandenburg, Germany factory. Commercial production of these tandem solar cells is imminent. Their Chief Executive Officer, David Ward, heralds this achievement as a testament to the remarkable performance of their tandem solar cells in panel assemblies. Fraunhofer ISE, utilizing Oxford PV's cells, has crafted a glass-glass tandem PV module boasting 25% efficiency, surpassing all silicon PV modules in industrial format. Prof. Dr. Stefan Glunz underscores the potential of tandem technology for the PV sector, given its compatibility with mass production techniques.

The research team addressed the temperature sensitivity of the perovskite layer by devising low-temperature processes for interconnection and encapsulation, ensuring gentle treatment of the cells. Dr. Achim Kraft notes the adaptability of these processes to existing PV production lines, making them suitable for industrial mass production. The team employed conductive bonding for cell interconnection, a method already utilized at Fraunhofer ISE's Module-TEC, with plans to explore low-temperature soldering.

CalLab PV Modules used a multispectral solar simulator to precisely determine module efficiency, essential for assessing the tandem module's power accurately. This approach involved illuminating both perovskite and silicon cell layers with LED light sources to replicate natural sunlight conditions, crucial for calculating efficiency over a designated area. While standardized measurement methods aren't fully compatible with this technology yet, field measurements validated the chosen methodology.

Fraunhofer ISE and Oxford PV are collaboratively striving for PV module certification, subjecting modules to rigorous long-term stability tests in climate chambers. This concerted effort signals a significant stride towards harnessing the potential of tandem solar cells, offering a glimpse into a future where solar energy generation achieves unprecedented efficiency and scalability.