Low-cost gel-polymer electrolytes for smart windows: effects on yearly energy consumption and visual comfort

The experimental analysis of the main figures of merit of an innovative electrochromic (EC) prototype, based on low cost gel-polymer electrolytes, is at the basis of the numerical simulation exposed hereafter, aiming at the assessment of energy and visual comfort benefits deriving from building integration of smart windows in a multi-storey office building. The effectiveness of the dynamic modulation of glazing properties to improve energy efficiency and users’ comfort was tested comparing the EC windows with a typical law-compliant static commercial glazing system and with a clear windows. To better understand the performances of the proposed EC film, six different locations – ranging from Seville to Helsinki – were selected throughout the European continent to conduct energy and daylighting analyses on three different exposures (east, south, west). The results obtained show reductions of summer cooling and winter heating as well in all the locations considered. Eventually, the effect of electrochromic switching of transmittance on the indoor visual comfort, is considered using a well-established metric: Useful Daylight Illuminance; with regards to daylight analyses, a significant reduction of hours in which excessive illuminance occurs was observed in all the locations considered, confirming that properly controlled EC devices improve both energy efficiency and visual comfort.