George Washington University (GWU)

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.

George Washington University (GWU) and their partners will develop a hybrid CPV concept that combines highly efficient multi-junction solar cells and low-cost single-junction solar cells. When direct sunlight hits the lens array, it is concentrated 1000-fold and is focused onto the multi-junction solar cells. Diffuse light not captured in this process is instead captured by the low-cost single-junction solar cells. The module design is lightweight, fewer than 10 mm thick, and has a profile similar to conventional FPV. Moreover, the combination of the two types of cells increases efficiency. GWU will use its expertise in micro-transfer printing to fabricate and assemble the multi-junction cells. This process will reduce manufacturing costs and further increase efficiency.

If successful, innovations from GWU in this 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