I have an existing 5.3 KW grid-tied roof mounted system. This only supports my home 100% for about 4-6 hours in the summer, and when the grid goes down the PV system also goes down and i live off the generator. I'm looking to expand my PV system with additional ground mounted panels and add a battery pack (looking at the Generac Power cell). I want to integrate the new PV/battery system with my existing gird-tied system and the generator so when the grid goes down, i can live off the sun and/or battery until it is drained and then have the generator kick in. Then when the sun provides enough power, the generator would shut down. I want to do as much of the work myself to reduce cost, but need to hire a electrical engineer (EE) or other smart person to design the system and act as a technical advisor during the installation process. I live about an hour west of Knoxville TN and east of Cookville TN. If anyone has experience with this type of setup, any help would be appreciated. Also if you know of a qualified EE for hire that would be helpful also.