German researchers have developed a technique for applying realistic designs to photovoltaic (PV) modules that allow them to imitate roof tiles, and blend more seamlessly into buildings.

The new method, called ShadeCut, was invented by a research team at Freiburg’s Fraunhofer Institute for Solar Energy Systems (ISE), one of the largest solar energy research institutes in the world. 

The foil cutting patterns can be used, for example, to imitate roof tiles without significantly impairing the efficiency of the PV module. Image: Fraunhofer ISE / Marco Ernst.

It enables complex visual patterns while also retaining approximately 95% of the power output of an uncoated module. The novel approach builds on the institute’s MorphoColor technology, a bio-inspired coating for solar panels.

It produces colour through microscopic structures rather than traditional pigments, and uses specially coloured films with transparent cut-outs to build designs that can resemble roof tiles, masonry or even custom graphics.

“The technology is particularly interesting for modules intended for integration into facades, roof-integrated PV, or even railings, especially on historic buildings,” says Martin Heinrich, PhD, a researcher at Fraunhofer ISE, as well as group leader for encapsulation and integration of photovoltaics.

Aesthetic solar panels

Driven by the iridescent wings of the Morpho butterfly, the MorphoColor method uses 3D photonic structures that manipulate light to generate vivid, angle-stable colours with minimal energy loss.

Marco Ernst, PhD, a researcher at Fraunhofer ISE and developer of the ShadeCut concept, emphasises that by structuring and cutting a colour-producing film, the team can embed colour effects and complex patterns directly into solar modules and facades.

“Additionally, there is the option to add further layers with cut-outs to create structures or additional colours,” says Ernst.

ShadeCut enables the customisation of PV systems, like with lettering or patterns. Image: Fraunhofer ISE / Marco Ernst

Following this biological model, researchers at the institute have also succeeded in applying a similar surface structure to the back of the cover glass of photovoltaic modules using a vacuum process.

Elaborating on the technology, Heinrich notes that ShadeCut uses laser or CAD-controlled processes to cut patterns into films carrying MorphoColor coating. 

Heinrich explains that ShadeCut modules can mimic masonry or roof tiles and match surrounding colours seamlessly. “It also allows for the customisation of PV systems, for example with logo lettering or patterns,” he adds.

High efficiency coatings

According to the team, the MorphoColor technology has surpassed its biological model in performance. Independent tests have shown that such coatings retain about 95% uncoated panels’ power. This makes the technology superior to comparable solutions on the market.

It, moreover, makes it attractive for applications where aesthetics have traditionally limited the adoption of solar panels. The researchers can apply the films to standard photovoltaics and solar thermal modules.

“Depending on the microstructure, cover glasses can thus be produced in various colours,” the researchers revealed in a press release.

Such adaptability could help expand the role of building-integrated photovoltaics (BIPV), where solar panels are used directly into the structure of a building rather than just mounted on top.

In addition, traditional black or blue panels often face resistance in historic areas or design-conscious projects. Colour-matched or patterned modules could make solar installations more acceptable, and even desirable.

The ShadeCut modules will be showcased at The Smarter E/Intersolar Europe 2026 in Munich, the world’s leading exhibition for the solar industry. It will be held between June 23 and 25.