In an embodiment, a unitized overhead glazing system of the present invention includes an array of assembled structural framing cassettes each having at least five photovoltaic modules. In an embodiment, each cassette forms one electrical string and is pre-wired, tested, and shipped ready to install for a variety of applications, including, but not limited to, parking canopies, covered walkways and specialty awnings. The unitized overhead glazing system can be utilized to generate electricity, provide shade, collect water, reduce heat island effect, provide more controlled lighting and support infrastructure for plug-in vehicles. The unitized overhead glazing system is designed to be installed and maintained from below, eliminating safety concerns associated with conventional canopies where work must be performed while on top of the canopy. The unitized overhead glazing system incorporates sealing methods and components to manage water, limit debris build up, and maximize energy yield.