New Developments in Dynamic Glass: Towards a New Era in Sustainable Construction

Abstract

Today’s green building certifications such as LEED, BREEAM, and HQE all recognize that a sustainable design is not just about energy efficiency and all integrate sections related to indoor environment quality, such as provision of natural daylight and views through windows. Yet, on the other hand, with the increasing stringency of building energy efficiency targets in Europe and indeed globally, we are observing an increasing trend to reduce window area in new building energy codes, as windows are often seen as the weak link in the building envelope. Creating both energy efficient and comfortable well daylit spaces could thus be a significant design challenge. Electronically tintable glass, also known as electrochromic (EC) glass, allows the building façade to become dynamic, changing the transmission of the solar heat and light in response to the exterior environment and the needs of the building’s occupants, while always remaining transparent. It thus offers a solution which avoids having to trade off daylight and views with energy performance, allowing more glass to be used without energy penalty AND without causing thermal or visual discomfort for occupants. New developments in the EC technology are reviewed here, as well as a range of new case studies of retrofit and new construction, where dynamic glass has provided increased flexibility for designers, and optimum balance between energy performance and comfort. In all cases, this technology empowered the architect to achieve sustainable design goals, without restricting their design freedom and aesthetics choices.