However, the most significant source is the generator. A simple magneto, or generator, produces electricity when a coil of copper turns inside a magnetic field. In a power plant, electromagnets spinning inside an armature of many coils of copper wire generate vast quantities of current electricity. The electrons are set in motion by a chemical reaction in a battery and flow only one way. The current is therefore constantly changing direction.
Electricity flows more easily through some materials than through others.
Conductors let electricity flow through them easily. Most metals are good conductors, so they are used to make wires for carrying electrical current. Insulators, such as glass, stop the flow of electricity. Most plastics are insulators. Wires carrying electricity are covered in plastic to prevent electric shocks.