Retrofit Window Energy Management System for Dynamic Control of Energy Flow Through Building Windows

Abstract

A retrofit window insulation system that achieves a very low solar heat gain coefficient (SHGC) of 0.10 or lower. The retrofit window insulation system is an ultra-lightweight, ultra-clear, low-e polymeric window cover that, in combination with solar screens and/or louvers that are mechanically deployable to offer optional shading for tunable control of daylighting and solar heating. Spectrally selective coatings on louvers which contain a phase change material (PCM) for thermal storage of daytime heat is particularly efficient. Placing a reflective film on the outward-facing surface of the louvers is reflective to sunlight but also emits thermal radiation back into the cold of space through the earth's atmosphere. If the louvers are placed between the retrofit window insulation system and the preexisting window glass, the air gap between the window and the retrofit window insulation system warms so that thermal energy is stored in the PCM.

Dependencies are inferred from the claim text.