In older, existing buildings in warmer areas of the country, windows are often the weakest link in the thermal enclosure and allow unwanted summer heat to enter the occupied space. Inefficient windows can allow up to 90% of direct solar gain to enter the living space during the summer months, leading to occupant discomfort and increased energy use from air conditioning. Technologies that reduce cooling energy consumption during peak demand will play a large role in reshaping how homes interact with the electric grid while meeting occupant comfort needs. Significant market opportunity exists for window attachments that can affordably control solar heat gain to occupied spaces of a residential building or apartment unit. The proposed technology for this SBIR Phase I grant opportunity is a site-specific exterior window shade that can provide a more cost-effective way of reducing peak cooling loads and energy use, and improving occupant comfort in existing and newly constructed single-family or multi-family residential buildings. While this technology is primarily suited for low-cost retrofit scenarios, it can translate easily to new construction as a lower-cost option to expensive window products or higher-capacity cooling systems. The technology is designed to optimize window shading by geographic location, size and orientation of the window. To assist homeowners, property owners, and installers to properly select and install the correct shade device for each window, a mobile-friendly specification and installation software tool will also be developed and provided with the hardware. The louvered shades on both the horizontal overhang and the vertical side projections of the device are lightweight and allow wind and snow to pass through them, minimizing any loads that could cause damage. The design of the shade device allows the louvers to be collapsed during packaging so the product can be shipped in a smaller package. Both the horizontal and vertical parts of the shade are expandable to fit many different sizes of windows. The product will minimize the Stock Keeping Unit count to 2-3 units, which will be sufficient to shade over 95% of typical window sizes. The product will be commercialized through manufacturer distribution channels and big box stores where siding, window and weatherization contractors can purchase the kits.
