Renewable energy has been on the forefront of our efforts to stop climate change, with solar power being a major focus. Within a given day, solar cell performance is higher around noon and lower during morning and evening hours. To maximize the performance of solar cells, many installations use mechanical tracking arrangements thus adding significant costs while reducing reliability. To improve the efficiency and make them independent of seasonal and daily variation, a novel curved solar cell array contoured to the inside of a hemisphere in conjunction with a specially designed domed lenticular lens is proposed. By contouring the solar cell with a curvature matching the “Petzval curvature” of the full optical system, the efficiency can be increased significantly provided the resulting irradiance remains in balance within the manufactured specification limits. By using proper combinations of curvature and specially designed optical assembly, the need for mechanical systems can be eliminated. Optical modeling was performed to determine optimal curvature and the optimal optical system. Efficiency of the solar cells were measured over three days at two hour intervals, as a base line, and was found to vary from 11.5% to 18%. Then, the optical system consisting of a Fresnel lens was positioned over the curved solar cell array. A 14% increase in peak efficiency was measured. The efficiency during morning and late afternoon also increased significantly over the base line, confirming the benefit of this apparatus. This innovative approach has the potential to increase the efficiency and reduce the cost of future solar panel installations.
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