When cracks appear in a solar cell, the parts separated from the cell might not be totally disconnected, but the series resistance across the crack varies as a function of the distance between the cell parts and the number of cycles for which module is deformed .
Cracking in Silicon solar cells is an important factor for the electrical power-loss of photovoltaic modules. Simple geometrical criteria identifying the amount of inactive cell areas depending on the position of cracks with respect to the main electric conductors have been proposed in the literature to predict worst case scenarios.
PV modules are supposed to have a lifetime longer than 20 years under the exposure to environmental conditions. Thermo-mechanical loads induce stresses into the components of the module, especially into the crystalline Silicon (Si) solar cells, which are affected by cracking 1, 2, 3, 4, 5, 6, 7, 8, 9.
Moreover, a perpendicular crack effect solar cell with 2 busbars has an estimated degradation of power equals to 1.5 Watt. Overall efficiency of the cracked surfaces is equal to 97.28% for a perpendicular to busbars crack which affects 3 solar cells (6 busbars), and 95.3% for a multiple directions crack which affects 3 solar cells.
1. Introduction Cell cracks appear in the photovoltaic (PV) panels during their transportation from the factory to the place of installation. Also, some climate proceedings such as snow loads, strong winds and hailstorms might create some major cracks on the PV modules surface , , .
As illustrated in Fig. 8 (b), the multiple directions crack affected 5 solar cells, reducing the power efficiency of the PV module up to 8.42%. However, the average reduction in the power for the multiple directions crack affecting 1 solar cell with an approximate broken area of less than 46.2 mm 2 is equal to 1.04%.