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Project Launch: 09/01/2021

Partners: Slipstream, Nicor

This project is a collaboration between utilities to assess the existing secondary glazing system market and determine the growth potential for this technology.


Secondary Glazing Systems (SGS) are window attachments with insulating high-performance glazing in anodized or painted aluminum frames with low-e coating on double-lite glass. With an estimated 20% savings over a typical single-pane window, the total market savings potential in ComEd's service territory is approximately 13.8 GWh, assuming full market saturation.

Despite improvements in window technology, the SGS market is still small in northern Illinois. There remain significant barriers to substantial growth in sales of secondary windows in ComEd’s service territory. A combination of market research, quantitative analysis and stakeholder engagement will be used to fully understand these barriers. After assessing the existing SGS market, the project team will focus on determining what market interventions would be most impactful and whether this measure is best suited for program deployment or market transformation.