High efficiency photovoltaic roof tile with static concentrator

The use of a static concentrator as an integral component within a photovoltaic roof tile has the potential to significantly lower costs by replacing expensive solar cells with relatively inexpensive acrylic lenses. A light trapping scheme based on a 3-dimensional rear surface structure for the roof tile enables reflected light from the rear to be skewed around so as to be totally internally reflected at the top surface interface with the air. This is achieved while retaining overall dimensions that fit within the constraints imposed by conventional roof tiles. This paper describes the construction of a prototype roof tile module and initial results of outdoor testing. Also given is a selection of bifacial solar cells that are useful for incorporation in the module.<
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