Sunlight Responsive Thermochromics - Dynamic Windows Made Simple

Dynamic windows offer an opportunity to save energy while enhancing a building’s environment and the occupants’ sense of wellbeing. A thermochromic interlayer with a continuously variable light transmission has been developed for windows that are sunlight responsive. Thus the heat of the sun can provide all the energy required to tint the window and block the much of the visible portion of the energy of the sun when there is sun shining directly on the window. The windows clear to a high visible light transmission state when the sun is not shining directly on the windows. The thermochromic system involves a temperature change induced thermodynamic shift in equilibrium of a reversible reaction. The chemistry that allows this to take place will be described and a status update on commercialization will be given.