Press Release: Researchers from the UWB have taken another important step in the development of smart windows

The team of Prof. Jaroslav Vlček from the NTIS research center of the University of Western Bohemia (UWB), Faculty of Applied Sciences (FAV) ( has taken a significant step in the development of windows that can control the passage of heat depending on the outdoor temperature. The scientists were the first in the world to successfully create a thin layer of vanadium dioxide over a large area of ​​ultra-thin glass foil measuring 0.3 × 4 meters.
Smart windows are based on the thermochromic effect, which is ensured by a very thin layer (approx. 400 nanometers) of one type of vanadium dioxide with a specific structure. This material changes its properties at a certain temperature and begins to reflect infrared radiation. As a result, the windows are figuratively closed to the thermal spectrum of solar radiation and thermal comfort is maintained in the building. This will significantly reduce air conditioning costs in the future.

The technology of industrial production of smart windows with vanadium dioxide has so far had a number of pitfalls. However, a team of Pilsen scientists has now managed to solve one of them – they were able to transfer the method of preparation of the thermochromic thin film to a large deposition facility. The vanadium dioxide layer was thus formed on an ultra-thin glass foil with a thickness of 100 micrometers (a little more than human hair) and dimensions of 0.3 m × 4 m. This means a further approximation to the industrial production of smart windows.

The successful implementation took place in the laboratories of the Fraunhofer FEP in Dresden (FhG) ( as part of the participation of Jaroslav Vlček’s team in the European research project Switch2Save, which deals with energy savings in air conditioning, including the application of thermochromic materials on building windows. Researchers from the West Bohemian metropolis were invited to the project based on the results of research into thermochromic coatings, which they published in prestigious foreign journals. They also presented their success at the meeting of the Switch2Save project, which took place at the beginning of November on the premises of the Faculty of Applied Sciences of the UWB.

“I am delighted that our eight-year research has been a success. This was also appreciated by our partners in the project, especially the representatives of the Fraunhofer Institute, where we successfully applied our know-how,” says Jaroslav Vlček. The Switch2Save research project, which addresses the highly attractive and societally important topic of energy saving through advanced surface treatment of window panes, brings together nine partners across the European Union. In addition to the coordinating Fraunhofer Institute, the researchers of the university (University of West Bohemia in Pilsen and the National University of Technology in Athens), technology companies, but also, for example, the second largest hospital in Greece, Agios Panteleimon. This is where the new windows will be tested in real operation. By the end of September 2023, a total of 56 window panes and balcony doors at pediatric and intensive care clinics should be installed in the hospital building.

The Pilsen team now faces another task – to improve the optical properties of the material, especially light transmission and color.

The original press release in Czech:

The achievement of the team of Prof. Jaroslav Vlček was also published in couple of national Czech newspapers: here, here, here

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement n°869929, project Switch2Save.