The use of numerical models for exploring the effects of nonuniform illumination in solar cells

To model solar cells accurately one must solve coupled second order, partial, linear differential equations derived from Boltzmann's equation, continuity equations and electrostatics. Analytical solutions prove to be insufficient for modeling complex applications such as concentrating systems. A network model and computer programs which use a sophisticated one-dimensional solar cell model were developed to simulate nonuniformly illuminated cells in concentrating systems.This project's task was to make these programs more efficient and to simulate nonuniform illumination cases with higher intensity levels and with spectral variations previously untried. To this end, modifications were effected resulting in a factor of one hundred reduction in the error of gvalue, an important model parameter, a reduction in running time by a factor of ten for the best cases and no less than two for the worst, and an overall simplification of the modeling process.Presented herein are the results of the simulations performed by the model. Eleven cases of nonuniformity previously untested were modeled at different levels of metalization and degrees of nonuniformity. A comparison of the results obtained was also made to previous work done in this field. In addition to the results of the simulations, the actual computer programs of the network model are included.