The energy-saving potential of solar PV vacuum glazing (SVG) insulated facades

Abstract

Buildings significantly impact global energy consumption and carbon emissions due to substantial energy losses through building envelopes. Enhancing the energy efficiency of building façades, a major component of building envelopes, is essential to addressing this issue. Solar PV vacuum glazing (SVG) insulated facades emerge as a potential solution by combining power generation with superior thermal insulation. Numerical simulations are conducted and validated against experimental data to evaluate the thermal, electrical, and overall energy performance of SVG-insulated façades compared to concrete walls, insulation walls, photovoltaic (PV) walls, and radiative cooling (RC) walls. The results indicate that SVG-insulated façades are the most effective in reducing heating loads and are second only to RC walls in reducing cooling loads, while also providing optimal thermal comfort. Compared to insulation walls, SVG-insulated façades reduce heating loads by 68 % in Beijing (cold climate) and cooling loads by 37 % in Hong Kong (hot climate). Although annual electricity generation is reduced by 4.3%–6.2 % due to elevated solar cell temperatures relative to PV walls, energy savings from enhanced thermal comfort partially offset this loss. Overall, SVG-insulated façades achieve substantial annual electricity consumption reductions, ranging from 147.8 kWh/m2 in Hong Kong to 290.9 kWh/m2 in Harbin, compared to concrete walls. This study confirms that SVG-insulated façades are valuable for improving building energy efficiency and reducing overall energy consumption.