This Bendy Solar Tile Just Proved the Experts Wrong About Rooftop Energy

TNO, the Netherlands Organization for Applied Scientific Research, has unveiled what it describes as the world’s first electrically functioning solar roof tile based on flexible perovskite solar cells. The tile achieves an energy efficiency of 12.4% despite its curved surface.

The announcement marks a potential turning point in building-integrated photovoltaics, a field that seeks to embed electricity generation directly into construction materials. By converting roof tiles into solar collectors, the approach aims to expand renewable energy capacity without placing additional demand on land or grid infrastructure.

The development comes as European governments and research institutions continue pushing to build domestic solar manufacturing capabilities, reducing reliance on supply chains outside the continent.

From Laboratory to Curved Rooftop

TNO developed the tile in collaboration with Dutch building-integrated photovoltaics specialist ASAT B.V., applying perovskite solar modules built on flexible foil onto a curved composite roof tile. According to TNO, bending the module to fit the tile’s contoured surface had only a limited effect on performance: standalone modules reached efficiencies of up to 13.8%, with 12.4% retained after installation on the curved tile.

The research organization described the project as the culmination of a complete development pathway, from small test cells in the laboratory, to 10-by-10-centimeter flexible modules, and ultimately to a tile that can be directly applied in practice.

Senior Scientist Ilker Dogan stated that, to his knowledge, this is the world’s first electrically functioning solar roof tile concept based on flexible perovskite solar cells. Roland Valckenborg, Senior Project Manager at TNO Solar, framed the significance in broader terms: “This allows roofs and infrastructure to generate sustainable electricity without compromising on design or aesthetics. This makes it an important step in the further development of solar energy in the built environment.”

A notable aspect of the project is the production method. The perovskite modules were encapsulated using an experimental roll-to-roll manufacturing platform developed by TNO, a continuous production technique similar in principle to newspaper printing, in which solar cells are deposited onto long rolls of flexible material. TNO noted that the materials and processes involved operate under normal conditions and are suited to large-scale roll-to-roll production, making them directly compatible with industrial manufacturing rather than requiring specialized laboratory environments.

Commercialization and European Industrial Goals

TNO has indicated it will continue working to improve the technology’s lifetime, reliability, and scalability. In parallel, the organization established a spinout company, Perovion Technologies, on March 11 to pursue commercialization of flexible perovskite solar modules.

Karl Kiel, founder of ASAT, said the demonstrator shows that a commercial introduction is on the near-term horizon.

The project was funded through a combination of regional, national, and European sources, according to TNO. Support came from the Province of North Brabant through its “Solar manufacturing industry to Brabant, Solliance 2.0” program, from the European Union’s Horizon Europe initiative via the LUMINOSITY project, and from the National Growth Fund program SolarNL.

The funding structure reflects wider ambitions to rebuild a competitive European solar manufacturing sector. Paul Gosselink, program manager of New Energy at the Brabant Development Agency (BOM), described the result as emerging from an innovation coalition launched in 2023 by TNO, the Province of North Brabant, and BOM, with a focus on next-generation flexible perovskite technology. He said the organization sees it as the beginning of new economic value and job creation in the region, and as a step toward reducing Europe’s dependence on non-European solar supply chains.

Martijn van Gruijthuijsen, deputy for Economy at the Province of North Brabant, said the goal is to improve solar energy, make it more affordable and more accessible, while building a foundation for increased production in Europe.

TNO’s work on perovskite cells has also extended to related areas, including roll-to-roll and spatial atomic layer deposition processes for solar cell layers and flexible foils. In July of last year, the organization joined Dutch manufacturer Solarge in presenting a lightweight prototype perovskite panel measuring 32 by 34 centimeters, a separate line of development from the roof tile project but drawing on related material science.