Solar century's solar tiles are integrated into a homes roof replacing the standard roof covering. The electrical tiles generate DC electricity from daylight, and even work on cloudy days. The DC energy is then passed via an isolation switch to an inverter which converts it to AC for use in the home. Neither the tiles nor the inverter contain any moving parts, so the whole process happens silently. The inverter is wired to the homes distribution board, where the electricity is exported to the national grid if it is not required for immediate use in the home. If energy is required, electricity from the tiles is used in preference to electricity from the grid. Switching from grid to solar electricity is an automatic process which happens silently without affecting the homes supply. Appliances function in exactly the same way but without causing carbon dioxide emissions. An energy display shows how much electricity is being used in the home, and what proportion has come from the solar tiles. At night, electricity is imported from the grid in the usual way. Solar thermal tiles for making hot water can be integrated alongside electrical tiles; heat from the sun is collected by transfer fluid and transferred to the hot water cylinder. The homes standard boiler is linked to the system to provide additional heat if required, and the hot water is piped around the home in the usual way. With solar hot water available for washing and bathing, solar thermal tiles reduce the amount of work the standard boiler has to do, which in turn reduces the monthly bills and the homes carbon dioxide emissions. Solar tiles can provide approximately half the energy for an average UK home, or all the energy required for an energy efficient home.