It's like any appliance, only instead of consuming energy it injects it into the local network! A plug & play solar kit generates solar energy using solar panels. The micro inverter converts direct current power from the panels into alternating current power used in your home. A special cable connects the micro inverter to a normal outlet in your home, injecting the kit's energy into the home's electrical circuit. This circuit works similar to a canal system. At different points there are devices that consume. The sum of that electricity consumption is what your electricity company provides to the home at the end of the channel system. Your meter counts how much light there is at each moment. If you now connect a plug & play solar kit to your canal system, that kit injects energy into that network. Connected appliances use that energy first. If you have several electrical circuits at home, they all come together in the electrical panel, which in turn is connected to the meter. If there is excess power on the circuit the kit is connected to, it will go first to the other circuits that require power.