The PV plant shows extreme soiling caused by smog and dust. Lack of structural integrity of the sheet metal roofing and mechanical damages at the module level were also observed. It is recommended to (i) increase the cleaning frequency to at least three times per month, (ii) replace and/or install UV cable protection means (iii) reinforce the structural integrity of the roofing material (iv) rearrange the modules based on the damage categories and (v) restring the circuits based on the shading conditions. The estimated production boost expected by the retrofitting actions lies between 17% and 22%.
Pipes carrying cables are brittle and some parts have already broken, exposing cables to UV radiation. The colors have already started to fade.
The simulation shows shading losses caused by the cables of 1.5%.
Total Estimated Energy Loss
The structural integrity of the roof shall be reinforced. The cables shall be protected from UV radiation by robust pipes or tubes.
A weather station, or at least an irradiation sensor on the module plane, shall be installed so that the performance of the system can be properly determined.
Manual cleaning shall be implemented and re-scheduled based on the results of a soiling study that adjusts the cleaning needs to each season.
Modules with heavy cracks shall be grouped in the same string or at least assigned to one MPPT. The grouping will be conducted based on infrared inspection with high irradiation levels and after cleaning. Modules with similar shading conditions shall be installed in the same string or at least assigned to one MPPT.