Thermal and Optical Performance of Advanced Polycarbonate Systems with Granular Aerogel and Hollow Silica Powder

Aerogel is characterised by high thermal insulation and light transmission, suitable for building envelope applications. Several aerogel-based products are available on the market, but innovation is still possible at both material and components levels. Aerogel glazing systems over perform standard one in winter, however the high insulation and high transmittance may cause overheating and glare in summer. This paper deals with optical and thermal characterization of an innovative glazing unit with a mix of aerogel granules and powder in the gap. The inclusion of powder could reduce light and solar transmittance, without compromising thermal resistance. Glazing systems with and without powder were assembled in different thickness and powder percentage. Optical properties were measured using a built-in spectrophotometer and the thermal resistance of selected samples with a hot-plate facility with the guard ring. Results demonstrated the impact of the aerogel powder in reducing solar gains in order to extend the current application of aerogel panels also to hot climates without neglecting the daylighting performance of the built environment.