My electrician installed 10 x 555 Longi panels to my existing 11kva mecer inverter with 2x mercer 4.8kva batteries. Panels are 2 strings of 4 and 6 panels . I use the Watcpower App. App shows that panels produce energy but I have not seen seen any reduction in my electricity account. Can anyone recommend a mercer accredited and reliable installer that can assess my system. Randburg