What are the types of PV systems?
There are basically 2 types of PV systems—stand-alone and grid-connected. Stand-alone systems operate independently of a utility grid and are normally used where no grid connection is possible, such as in remote areas, for portable highway signs, etc. Some stand-alone systems produce only DC power, but stand-alone systems can also produce AC power. Prior to 2002, stand-alone PV systems were the most common, but since 2002, more PV generation has been attributed to grid-connected systems than to stand-alone systems. One reason for this transition is that fully-interactive, grid-connected, systems optimize the use of PV electricity. The reason for this is that when the grid is available for a fully interactive grid-connected PV system, none of the energy generated by the PV system is wasted. Any electricity generated by the PV system that is not used on site is sold back to the utility for someone else to use. Grid-connected, but not interactive, PV systems use the utility grid as an aux
