Project description
New energy saving solutions for large glass façade areas
A considerable number of non-residential buildings in European cities use large windows and glass facades for aesthetic and representative reasons. However, glass-based parts are responsible for energy losses in both the winter and summer. The EU-funded Switch2save project proposes new materials that reduce energy demands in buildings with large glass areas. Their method involves the integration of transparent energy-smart materials with switchable total energy transmission values (g-value) to control the entrance of solar radiation. Switch2save has a unique performance, reduces manufacturing costs and increases opportunities for shadow solutions. Two prototypes will be tested in two buildings with large glass façade areas, a hospital in Greece and an office building in Sweden.
Objective
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.
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Funding Scheme
IA - Innovation actionCoordinator
80686 Munchen
Germany