A typical home with electric service from a utility needs no modification to the electrical wiring of the home. Solar panels, also called modules, can be mounted on the roof, or on a ground mount nearby. In the case of a roof mount there is normally a low profile system of special aluminum extrusions which hold the modules. The modules come with wires which plug together to make electrical circuits which lead to a disconnect at ground level. From here, the circuit goes through an inverter, which converts the electricity to standard AC voltage, usually 240V in the US. The output of the inverter is then connected to the electrical system of the home. Usually this is done by adding a 240V circuit to the existing load center - your normal service panel. The inverter is able to sense the utility electricity and synchronize it's output to it perfectly. The energy from the solar panels is therefore mixed together with the utility electricity. If the solar system is producing more energy than you are using, it flows to the grid, and is used by your neighbors. "Net Metering", if offered by your utility, means you receive credit for each kWh at the retail price. The meter "spins backwards" and your electric bill is reduced.