Solar photovoltaic (PV) panels convert sunlight directly into DC electricity. The following energy outputs can be used as a rough rule of thumb for the UK (assuming a reasonable tilt, orientation and system efficiency). 1m2 crystalline array will provide a useful output of 90-110 kWh per year and 1m2 triple-junction thin film array will provide a useful output of 60-80 kWh per year. Grid connect means that the output from the solar panels is delivered direct onto your electricity distribution board (knocking units off your bill). If you change your electricity tariff to Ecotricity or Npower you can get a special solar tariff and get paid for exported units! If you are in the UK don't forget to check our funding page which has details of grants available for domestic solar PV systems.