ABSTRACTWe have measured the intensity of electroluminescence (EL) and its energy spectrum in a-Si:H solar cells having an initial energy conversion efficiency from 5.75 to 9.8 %, and open-circuit voltages (Voc) between 0.799 and 0.952 V. We found that (a) at room temperature, EL efficiency is proportional to the initial solar cell energy conversion efficiency; (b) the defect energy distribution in the i-layer can be detected by EL energy spectrum at room temperature; and (c) Voc is simply related to the quasi-Fermi level splitting obtainable in the i-layer and that the buffer layer serves to increase this splitting.
Optimization of harvesting solar cell energy based on MPPT to be applied during the rainy season in the tropics