Electricity generation is the process of generating electric power, expressed in terms of gigawatt-hours. Solar Photovoltaics (PV), also known as solar cells, are electronic devices that convert sunlight directly into electricity. A grid-connected photovoltaic system, or grid-connected PV system is an electricity generating solar PV power system that is connected to the utility grid. A grid-connected PV system consists of solar panels, one or several inverters, a power conditioning unit and grid connection equipment.