A solar photovoltaic (PV) system converts sunlight into electricity. Sunlight is captured by the solar panels and converted into usable electricity by the inverter. This can then be used to power appliances in your home directly, or stored in a battery for use later when the sun is not shining. If not used or stored, the excess electricity is exported back to the grid.
Systems installed before March 2019 were eligible for the Government Feed in Tariff which paid for electricity generated and exported to the grid. The scheme is now closed but if you already have a Feed in Tariff, from EDF Energy or another supplier this will continue. Details of the EDF Energy scheme are here
The Solar Export Guarantee will replace the Feed in Tariff. It will pay for electricity exported to the grid and will start in January 2020. Announcements will be made here