Thermal insulation performance of an advanced photovoltaic vacuum glazing: A numerical investigation and simulation

Abstract

Structural details of an advanced laminated PV (photovoltaic) vacuum glazing are illustrated. The glazing design features low heat gain or loss, while the sandwiched PV film generates electricity and allows daylight and vision. The thin vacuum gap and glass sheets make it slimmer and lighter than conventional designs. Aerogel support pillars and epoxy resin edge seals minimise conductive heat transfer and further reduce the weight of the window. The thermal insulation performance of the PV vacuum glazing is numerically investigated. All the three heat transfer mechanisms are considered in the COMSOL modelling. During the modelling of radiation in participating media, the optical properties of low-e (low-emissivity) and PV coating are considered and a boundary condition for translucence is re-customized in particular. For the verification of the modeling accuracy, a simplified vacuum glazing model is adopted first. The simulation results are consistent with the thermal performance data report of a vacuum glazing manufacturer. Subsequently, comprehensive simulation results with different configurations of the PV vacuum glazing are presented and discussed. Retrofitting of steel pillars with aerogel pillars for conventional vacuum glazing can yield a decrease of 0.3255 W/m2 K in the overall U-value and a decrease of 0.2559 W/m2 K in the central U-value. Besides, the thermal resistances of the laminated structure are calculated layer by layer. Moreover, the influence of the radiative parameters of the PV film on the thermal performance of the glazing is assessed. On the other hand, the simulation of the PV vacuum glazing under solar radiation is carried out to evaluate its working temperature.