The surface of the panels may be cleaned using neutral soap and water, wiping carefully and without using abrasive material. Denatured alcohol (methylated spirit) can be used to remove grease, etc
Solar Panel Mounting Systems

VELCRO® Brand products are used to mount flexible solar panels to buildings with flat membrane roofs. The system can be rapidly installed, without penetrating the roofing system, is easy to maintain, and is removable. The largest system of its kind in the world was completed at a General Motors facility in Zaragoza, Spain, utilizing 85,000 solar panels and over 250 miles of our hook and loop fastening system.
VELCRO® Solar Panel Mounting Uses & Benefits
•   Flat membrane roof installations with flexible solar panels
•   No roof penetrations
•   Removable
•   Labor savings
M.S.I.E. SUNPORT 2020 Installation guide                            for download
M.S.I.E. VIDEO on installation                                                for download