Energy efficient vacuum glazed window: A system design and investigations on hermetic sealing materials

Predictions by Fang et al (2010) indicate that triple vacuum glazing can theoretically achieve a centre of pane thermal transmittance of less than 0.26 W/(m2.K). To date two materials indium and solder glass have been used for sealing the edges the glass sheets in a vacuum glazing. Indium is a low temperature sealing material (157C) but is very expensive. Solder glass is a high temperature sealing material (around 450 C). One of the main hindrance to the manufacture of vacuum glazing at the industrial level is the cost. In this poster presentation, a vacuum glazing system for production at a laboratory scale using a modified evacuation pump-out sealing technique is presented. A number of samples have been fabricated using existing and new sealing materials that achieve a vacuum pressure less than 0.001Pa in the cavity of the vacuum glazing samples. An experimental performance verification of samples using new cost effective sealing materials will be executed in a hot box calorimeter to measure thermal transmittance performance of the samples. Issues associated with degradation of the vacuum pressure inside the cavity can be addressed by introducing non-evaporable getters.