University of Rochester

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.

The University of Rochester along with partners Arzon Solar and RPC Photonics will develop a micro-CPV system based on Planar Light Guide (PLG) solar concentrators. The PLG uses a top lenslet layer to focus and concentrate sunlight towards injection facets. These facets guide and redirect light, like a mirror, towards a PV cell at the edge of the device. Combined, these methods lead to higher efficiency over conventional FPV systems. At fewer than 3 mm thick, the system will be thin and flat, similar to traditional FPV panels. The PLG system also reduces complexity and costs by only requiring PV cells at the edge of the device, instead of an array of thousands of micro-PV cells. The team will also develop a scalable fabrication technique that uses grayscale lithography to produce the micro-optics.

If successful, innovations from the University of Rochester’s project may lower the cost of solar systems by allowing 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.