ANALYSIS FOR DIFFERENT MATERIALS USED AS UP CONVERTERS WHEN INCORPORATED IN BIFACIAL SILICON SOLAR CELLS USING THE PROGRAM PC1-D

摘要

A complete and detailed description of the physical processes occurring in the up conversion phenomena is very difficult to accomplish with complete accuracy. On the one hand, it would be necessary to know how it is distributed luminescent centers in different energy sublevels; and secondly, how does the propagation of light in the converter, and how to deal with this phenomenon. Considering these factors, the objective of this work is to obtain comparative results (I × V) for different materials used as up converters (UC) when incorporated in bifacial silicon solar cells using the unidimensional program PC1-D, in order to get the best candidates for use as UC. Up conversion phenomena consists generally of a non-absorbent matrix containing luminescent centers at a given concentration. The absorption and emission resulting from the luminescence were simplified considering the luminescent center as a series of three energy levels. With the mathematical approaches developed, was obtained tables with photon density per unit for all ranges of wavelengths, between 300 and 2100 nm. The simulation was performed assuming a bifacial silicon solar cell already experimentally characterized and contrasted with theoretical data. Forms of illuminations have been modified for this solar cell considering the information of UC, where changed the intensities constants (transmitted sunlight) and conversion efficiency. The simulations of I × V curves demonstrated that UC which absorb at wavelengths between 1800 and 2000 nm have a better potential in relation to others, the efficiencies found (～20%) for solar cells with UCs implemented are shown below the limit values calculated (～36%). However, approaches the values found in practice (～16%) and modeled.