Lightweight switchable smart solutions for energy saving large windows and glass facades destiny
Start: 10.2019 – Duration: 48months

HMCS.NTUA is participating in the European project Switch2save: Lightweight switchable smart solutions for energy saving large windows and glass facades (H2020-NMBP-ST-IND-2018-2020) along with 9 partners covering 6 European countries.

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 windows-to-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.

HMCS.NTUA main activities in the project are:

  • Energy performance assessment of EC, TC and combined configurations (Insulation Glass Unit – IGU) at “element” and “building” levels
  • Development of tools for thermal bridge calculation and assessment
  • In situ measurement of IGU U-values in pilot testing facility (mock-up)
  • Reaction to Fire testing of IGUs
  • Assessment of lighting; photo-metric assessment of IGUs and novel EC and TC combined configurations
  • Support demonstration monitoring campaign in Greece, before and after interventions with novel IGUs
  • Life cycle assessment, Life Cycle Costing and development of Key Performance Indicators (KPIs) to holistically assess performance of novel IGUs
  • Dissemination and communication activities

More information can be found here
Switch2Save EU Cordis
Press Release

The project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 869929.