Texas Engineering Experiment Station (TEES)

The use of flat-panel solar photovoltaics (FPV) is growing dramatically as costs decrease. By contrast, more efficient concentrated PV systems (CPV), which focus direct sunlight onto a single point, have not been widely adopted because of their high cost, large size, and expensive tracking systems. A new approach, micro-scale concentrated photovoltaic systems (micro-CPV), may deliver the cost and size benefits of conventional FPV systems, but with an estimated 50% performance improvement. Micro-CPV modules would use cost-effective trackers and generate more electrical power in a given area. This allows installation on space-constrained residential rooftops and decreased costs for commercial and utility applications. Finally, the MOSAIC systems would have the ability to capture both direct and diffuse sunlight, which could make CPV economical in more geographical regions. These innovations could spur the expanded use of PV to generate clean, renewable energy.

Texas Engineering Experiment Station (TEES) and their partners will build a micro-CPV system that incorporates waveguide technology. A waveguide concentrates and directs light to a specific point. TEES's system uses a grid of waveguides to concentrate sunlight onto a set of coupling elements which employ a 45 degree turning mirror to further concentrate the light and increase the efficiency of the system. Each coupling element is oriented to direct its specific beam of light towards high-efficiency, multi-junction solar cells. Further system efficiency is gained by capturing diffuse light in a secondary layer. The system also includes a secondary layer that captures diffuse sunlight, increasing its overall efficiency.

If successful, innovations from TEES’s project may lower the cost of solar systems by enabling economical, high-volume manufacturing of micro-CPV arrays. Improved systems could encourage greater adoption of solar power in all three primary markets – residential, commercial, and utility.