Building-Integrated PV (BIPV) plays an important role not only in replacing conventional building materials and generating electricity, but also in saving space that would otherwise be used for nothing or for standalone solar installations. One such BIPV solution at Intersolar Europe 2025 was Fraunhofer ISE’s solar roof tiles.
Fraunhofer ISE has partnered with Freesuns to set up a new solar roof tile production line at Module-TEC in Freiburg. This pilot line will manufacture a total of 4,000 roof tiles, of which 800 have already been manufactured. Freesuns, a Swiss-based roof tiles manufacturing company, has partnered with Fraunhofer ISE, as part of the SPHINX (Sustainable Photovoltaics Integration in buildings and Infrastructure for multiple applications) research project and is currently installing these roof tiles on 5 buildings in Switzerland. These tiles were also on display at Fraunhofer ISE’s booth at Intersolar Europe 2025.
“By manufacturing the first matrix shingling Freesuns solar roof tiles in Fraunhofer ISE's Module TEC, we can collaborate on the production development and demonstrate the great advantage of matrix technology. Our focus in developing this product is on applications for existing buildings, especially those listed as historic structures,” says John Morello, founder and CTO of Freesuns.
The roof tiles feature the matrix shingle technology developed by Fraunhofer ISE. In this configuration, the cells are electrically connected simultaneously in series and in parallel, which ensures that the current flows around the shaded area. The space is optimally utilized by laterally arranging the shingled cells. The research institute also boasts 2%-6% relatively higher module efficiency compared to other half-cell modules with similar dimensions. Other claimed advantages of this technology are: adaptability to building and facade geometry, 100% lead-free interconnection, up to 110% more power in partial shading, and competitive manufacturing costs compared to conventional half-cell modules.
The solar roof tiles have dimensions of 450 × 510 mm with a glass-glass configuration. The cells are based on TOPCon technology connected in a shingled matrix. These tiles come in various color options for aesthetic enhancement. Fraunhofer claims that this is achieved with a high color saturation using its in-house developed coating known as MorphoColor®.
“Matrix shingle modules are predestined for integrated applications, especially in building facades and, as here, as photovoltaic tiles on roofs. This is precisely where maximum space utilization, shading tolerance, and attractive aesthetics are important,” says Torsten Rößler, project manager at Fraunhofer ISE.
The new pilot line at Fraunhofer ISE’s Module-TEC uses a fully automated matrix shingle stringer by M10 Industries AG, which can produce solar cell matrices in flexible shapes, claims Fraunhofer ISE. It also states that the amount of adhesive used in shingling, the size and overlap of cells, and the duration and curing temperature can be optimized within the stringer.
