PV connection to the grid
A grid-connected photovoltaic power system, or grid-connected PV system is an electricity generating solar PV system that is connected to the utility grid. A grid-connected PV system consist of solar panels, one or several inverters, a power conditioning unit and grid connection equipment. They range from small residential and commercial rooftop systems to large utility-scale solar power stations. When conditions are right, the grid-connected PV system supplies the excess power, beyond consumption by the connected load, to the utility grid.
The term off-grid refers to not being connected to a grid, mainly used in terms of not being connected to the main or national electrical grid. In electricity, off-grid can be stand-alone power system or mini-grids typically to provide a smaller community with electricity. Off-grid electrification is an approach to access electricity used in countries and areas with little access to electricity, due to scattered or distant population.