The rooftop solar system can be majorly classified into the following 3 types:
Off-grid: These Solar PV systems are deployed in remote locations, where access to grid electricity is limited or non-existent. The system generates power during the day, which can be stored in batteries. The power generated can either be consumed during the day simultaneously or during the night by utilizing the storage devices.
Grid-connected: Rooftop PV Systems connected and operating in tandem with grid electricity are called Grid-Connected Rooftop PV (GRPV) systems. These are deployed in urban areas with reliable access to grid. The system generates power during the day, which is deemed to be consumed first by the household or load and only in the case when generation is excess does it get sent to the grid. Owing to the reduced consumption from the grid, the consumer is compensated in the monthly electricity bill.
Hybrid (Grid-tied with storage): A hybrid system uses one or more combinations of Rooftop PV systems, grid connection and storage devices. Although expensive, such systems have the advantage of power continuity and increased reliability during either non-solar days or shortage from the grid.