SAGE Electrochromics, Inc. SAGE Electrochromics, Inc. - How it Works


The illustration on the right shows what happens when a SageGlass window is switched. (A) The SageGlass coating on the glass is made up of five layers. When voltage [less than 5V DC] is applied to these layers in their “clear” state, they darken as lithium ions and associated electrons transfer from the counter electrode to the electrochromic electrode layer. (B) Reversing the voltage polarity causes the ions and associated electrons to return to their original layer, the counter electrode, and the glass untints. This solid state electrochromic reaction is controlled through a low voltage DC power supply. When the SageGlass coating darkens, the sun’s light and heat are absorbed and subsequently reradiated from the glass surface much the way low-emissivity glass also keeps out unwanted heat.

How SageGlass technology works
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This diagram shows the all solid-state SageGlass five-layer coating on glass. The transparent conductor layers (TC) form a sandwich around the electrochromic layer (EC), the ion conductor (IC) and the counter electrode (CE), allowing a voltage to be applied to the “stack” of layers. The appropriate condition for tinting the coating is shown, where a positive voltage is applied to the TC in contact with the CE, causing lithium ions to be driven across the IC and inserted into the EC layer, while a charge compensating electron is extracted from the CE, flows around the external circuit, and is inserted into the EC layer.

EC Basics diagram

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After coating the individual panes of glass with the layers described above, SAGE fabricates them into industry standard insulating glass units (IGUs). These IGUs are then installed into frames supplied by SAGE’s window, skylight and curtainwall partners or by a supplier chosen by the architect or builder. Once installed in a building, the SageGlass IGUs are operated by acontrol system control system designed by SAGE. The configuration of the control system can be customized depending upon the needs of the project: windows, skylights and curtainwall can be controlled by a building automation/control system, manually using wall switches, or a combination of the two. The SageGlass control system wiring conforms to the requirements for NEC® Class 2 circuit, and is powered by UL listed power supplies, ensuring that the entire system meets industry standards.