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How much power do solar modules loose in their lifetime due to cell cracks?

I ndeed. A crack in a solar cell may not be visible to the naked eye, but it may have adverse effects on PV module power output. The tricky issue about cell cracks is that they are a dynamic phenomenon, and they open and close more or less randomly as the module undergoes handling, transportation, thermal cycling, and flexing in the field. NCPRE has developed a particular Dynamic Mechanical Loading (DML) in situ-EL imaging setup (Page 9) which mimics the way modules are installed in the field. Also, NCPRE has developed a new accelerated test by optimizing the combination of variables like frequency of cycle, the number of cycles, the pressure applied. It was found that the PV modules reach a point where all cell cracks that tend to open up have opened and the module power loss reaches a maximum value and does not increase anymore. It assesses the vulnerability of different module designs to suffer power loss due to cell cracks. This would also be useful in evaluating the impact of existing cell cracks on the power loss which is often the case when the PV plants change hands.

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