Photoluminescence imaging

Photoluminescence imaging appears in a list of advanced inspection methods for PV plants, in the form of advanced outdoor photoluminescence imaging of PV modules. That list follows the description of corrective measures, which are meant to limit losses and costs once a failure has already occurred. One electroluminescence image taken at a single bias current and temperature cannot always pin down the physical cause of a defect. Photoluminescence can be used with EL images taken at two bias currents, infrared thermography or laser-beam induced current to explain why the EL signal varies across a module. In laboratory work, photoluminescence images of a silicon heterojunction cell in a glass/glass laminate were taken at 0 h, 500 h and 1000 h of damp heat testing to follow its degradation.

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• sentence 5: support check: partial - The figure caption shows PL images of one SHJ glass/glass cell at 0, 500 and 1000 h of DH testing, but it does not say they were laboratory work or that the aim was to follow degradation (though the caption links it to degradation mechanism). -->