Some modules with mechanical damages were detected (micro-cracks and burned cells). Cables hang under the modules. Interrow distance is insufficient. Structural earthing is incomplete and corroded. It is recommended to (i) increase the cleaning cycles, (ii) replace damaged modules and cables, (iii) retrofit the mounting structure, (iv) install a new earthing system, and (v) install a weather station or at least an irradiation sensor on the module plane to quantify and monitor the Performance Ratio, (vi) remove objects under modules. The estimated production boost expected by the retrofitting actions lies between 10 and 15%.