1. —Two power conditioning units (PCU)’s needed only if batteries are added for grid failure —AC output is consistent with the requirements of most loads. —excess energy delivered to grid and grid used for storage & backup —Safety feature is required to ensure the PV system will not feed back into the utility grid — when the grid is down for service or power outages Ref: http://www.fsec.ucf.edu Grid-connected PV system power conditioning units