Hebrew University team makes flexible, see-through solar cells for windows

Most solar panels are rigid, dark and opaque, which limits where they can go. Researchers at the Hebrew University of Jerusalem have described a different kind of device: flexible, semi-transparent solar cells whose colour and transparency can be tuned, designed to be built into windows, building façades and curved surfaces. The work, led by Professor Shlomo Magdassi and Professor Lioz Etgar of the university's Institute of Chemistry and Center for Nanoscience and Nanotechnology, with Vikas Sharma, Ouriel Bliah and Tal Binyamin, was published in the journal EES Solar and announced on 12 January 2026.

The cells use perovskites, a family of crystalline materials that have become one of the most promising alternatives to silicon. The team's key idea was to control how much light passes through not by thinning the light-absorbing layer, but by adding microscopic polymer pillars made by 3D printing, and by adjusting the thickness of a transparent electrode. Changing those parameters alters how see-through the device is and what colour it appears, without altering the solar material itself.

In laboratory tests the cells reached power-conversion efficiencies of up to 9.2 percent while letting through about 35 percent of visible light on average, and they kept working after repeated bending and during extended operation. The fabrication process runs at low temperatures and avoids toxic solvents, which the researchers say makes it better suited to environmentally friendly manufacturing. Magdassi said the goal had been to rethink how transparency is achieved in solar cells.

The team's next steps are to improve long-term durability with protective encapsulation and barrier layers, a common hurdle for perovskite devices, with a view to eventual commercial use.