Improving photovoltaic efficiency

Researchers report a method to improve solar cell efficiencies by combining current solar technologies. Concentrator photovoltaic (CPV) modules, which focus direct sunlight onto multijunction solar cells, are more efficient at converting sunlight to electricity than other solar technologies, offering a low-cost energy source in regions with high direct sunlight. However, CPVs cannot effectively use diffuse sunlight, limiting their geographic deployment. To capture direct and diffuse light, John Rogers and colleagues designed solar modules that stack or attach flat plate photovoltaics behind CPVs. While the CPV collects direct light, silicon cells on the flat plate photovoltaics capture diffuse light, which the concentrator optics of the CPV fails to direct to the arrays of multijunction solar cells. Outdoor testing of the modules in Durham, North Carolina, Bondville, Illinois, and Washington, DC, resulted in average daily efficiency gains of 1.02-8.45%, depending on weather, over standard CPV modules. According to the authors, the model could expand the geographical deployment and cost effectiveness of photovoltaic power generation. - Read at PNAS.org

Article #16-17391: “Concentrator photovoltaic module architectures with capabilities for capture and conversion of full global solar radiation,” by Kyu-Tae Lee et al.