Start date
October 1, 2019
48 months
End date
Overall budget
6.4M €
Number of partners
John Fahlteich
Project Coordinator
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP
Lenka Bajarová
Project and Dissemination Manager
AMIRES, The business innovation management institute, z.u.

Lightweight switchable smart solutions for energy saving large windows and glass façades


Between 25 and > 60% of total energy transfer through building envelopes is driven by glass based components such as windows, glass facades and glass roofs. In winter, heating energy demand of buildings with high window-wall ratio (WWR) in north- and east direction is up to 35% higher compared to buildings with only small windows. In summer, large windows and glass facades result in high heating of the building interior: cooling energy demand is increased by a factor ≈ 1.5 to 5 when WWR increases from 10% to 90%. Non-residential buildings often make use of large windows or glass facades for building-functional and representative reasons and therefore hardly suffer from increased energy demand. Switch2save targets active management of radiation energy transfer through glass-based building envelopes by integrating transparent energy smart materials with switchable total energy transmission values (g-value). Such materials are electro-chromic (EC) or thermo-chromic (TC) systems. Intelligent switching of those allows significant reduction of both heating energy demand in winter and cooling energy demand in summer.

Switch2save’s unique and lightweight combined EC and TC smart insulating glass unit will be a breakthrough in performance (plus 20%); low-cost potential (minus 33% manufacturing cost) and increased design opportunities compared to state-of-the-art smart shading solutions. Switch2save prototypes will be demonstrated in two representative buildings – a hospital in Athens, Greece and an office building in Uppsala, Sweden by replacing > 50 windows and 200 m² glass façade area. Continuous monitoring of energy demand at thermal comfort levels inside the buildings for at least one year before and after TC/EC integration will verify energy saving potential of Switch2save solution. Switch2save increases the market and application potential of energy smart glass in buildings – targeting the whole building glass market of 4.7 billion square meters produced per year.


AMIRES was involved in the project’s preparatory phase and in the negotiations. Within the project it is responsible for administrative project management and for dissemination of results.


  • Partners:
    • Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP and Fraunhofer Institute for Silicate Research ISC, Germany
    • ChromoGenics AB, Sweden
    • School of Mechanical Engineering @ National Technical University of Athens, Greece
    • University of West Bohemia, Czech Republic
    • SIA AGL Technologies, Latvia
    • Vasakronan AB, Sweden
    • General State Hospital of Nikaia “Agios Panteleimon”, Greece
    • VAN ROMPAEY SARA, Belgium
    • AMIRES, The business innovation management institute, z.u.., Czech Republic


This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement n°869929, project Switch2save.