Question

Where does the initial wall socket alternating current come from?

Answer 1

The alternating current in wall sockets of our houses is initially produced by huge AC generators at power plants using some other form of energy (nuclear, hydro, thermal, etc)

The AC (alternating current) produced in power plants is distributed at high voltage to local station through high tension lines (the huge electrical towers we see around). At local stations this high voltage AC is brought down to lower voltage (may be in several steps) and fed to our homes at 110V 60Hz (or whatever be the country standard). At our homes this AC first comes through metering device to main distribution box. From this distrbution box the AC comes to various socket points and other electrical devices (bulb, air conditioner, refrigerator, etc)