Electroluminescence imaging – EL photos, is the technology that allows to penetrate inside the PV modules and detect any invisible defects. Such defects cannot be detected with bare eyes or by any other means such us thermography or I-V characteristics. Electroluminescence is such an X-ray photo, and shows the inside defects of the PV modules (solar cells), such as cracks, micro-cracks, disoldering problems, etching and dead cells.
Such invisible internal defects, probably in the beginning cannot influence the power output of the PV module. As the time passing combined with the environmental influences, such defects are enlarged and cause problems to the modules. Especially, the micro cracks and disolderings can create hot spots or burn out the modules.
Micro cracks and disolderings on modules, can be formed during cells production process, modules assembly and encapsulation, transportation, installation, lighting and hailstorms, heavy snow as well as and also bad maintenance of the park.
For the brand new PV parks, in many countries recently, investors special with large-scale PV projects demand EL photos for the entire number of PV modules from independent company before commissioning. In that way, investors know exactly the inside quality of their PV modules and the quality of the investment. If there are some problems, investors can take from the beginning the right actions. Also investors create from the beginning an EL photo reference for the PV plant, for future use for insurance companies.
For operating PV plants, the creation of EL photos reference, are very useful too, for the investor. He knows the quality of his modules inside and also creates EL Photo reference for insurance companies, in order to refer or claim things.
There is a strong belief that EL Photos are necessary after strong hailstorms & lightings or heavy snow, because then can be formed inside the module, invisible micro cracks or contact burns in the solar cells, that can be detected from the beginning, only with EL photos. These defects, will create crucial troubles in future and the modules have to be substituted. If the park has a reference with EL photos before the storm, then easily with comparison, the investor can prove to the insurance company, how the park was before the storm and how is after the storm strike.
These services are new and many of our customers, the last three months have proceed to ELphoto examination and have EL Photos reference for their parks, mostly for the insurance companies.
With EL Photos can be detected:
- Invisible cracks and micro cracks on solar cells.
- Quality of inside contactors ( Solderings , disolderings )
- Etching of solar cells.
- Dead solar cells.
- PID or LID phenomena
- Snail trails and their reasons
- Discolorations of PV modules and their reasons
- String dark I-V curves and comparison of strings.
SENERS can prepare EL Photos file for any PV park. The EL Photos are taking from experienced engineers and ONLY during the night. There is no any movement or de-installation of solar modules.