Performance of Sealed Curtain Wall Spandrel Panels that Direct Deep Sunlight into Multi-Story Buildings

(This entry contains a BEST4 Conference paper and a Powerpoint presentation in PDF format.) A novel solution to overcome problems associated with the use of excessive window areas and shallow floor plates for daylighting buildings is to use active sunlight tracking systems to deliver controlled sunlight to areas that are inaccessible by conventional methods. This technology is commercially available to designers with minimal limitations to building orientation and form. The technology tracks the sun at the top of the building with an array of motorized mirrors and redirects a stationary beam of sunlight to concentrating optics located in sunshades and spandrel panels on each floor of the building. The concentrated beam of sunlight from the spandrel is distributed through the building using hybrid light pipe technology and fixtures. This paper addresses the challenges of integrating an optical system into the building envelope, including limitations on insulation thickness, requirement for clear glass to the exterior and interior of the spandrel, and controlling dust and moisture within the spandrel to maintain the effectiveness of the optics. By means of analysis, testing, and validation, this system is compared with conventional curtain wall spandrels for controlling heat, air, and moisture.

(This entry contains a conference paper and presentation in PDF. For optimal viewing, open in Adobe Acrobat Reader.)