Redução da potência em módulos fotovoltaicos : análise dos parâmetros elétricos iniciais e da degradação dos primeiros anos em condições externas

Abstract

The decrease in the power of photovoltaic (PV) modules after installation can occur due to the degradation suffered by the module, which depends, among other factors, on the structure of the solar cell, the materials used in the manufacture of the PV module and the environment. The present work analyzes and compares PV modules with Al-BSF technology solar cells, multi and monocrystalline silicon (Si-Mc and Si mono, respectively), installed in three rural properties in the west of Paraná. Test PV modules were installed into the PV systems and reference modules were stored, being electrically characterized after periods of operation/storage, allowing to evaluate the evolution of the electrical parameters and through them the degradation rate, as well as the effect of soiling on the test PV modules in operation. Prior to the installation in the rural properties, the electrical characterization of the PV modules revealed higher nominal powers than those specified by manufacturer datasheet. After the exposure period, the degradation for Si-Mc modules was in the range of -4.4% to -5.0% (in 3 years) and for Si-mono modules was -1.7% (2 years), differing from the manufacturer's forecasts of -3.7% for Si-Mc PV modules (in 3 years) and 3.5% for Si-mono PV modules (2 years). The stored Si-Mc PV modules showed a power drop of -2.4% and -3.5% (for rated power of 270 Wp and 325 Wp, respectively) while the Si-mono modules showed a decrease of only -0.8%. The degradation estimated by the performance ratio of the PV systems was similar to that calculated through the electrical parameters solely for the PV modules with lower soiling.