The basic principle is that the coils are kept stationary while magnet is turned inside the coil. The stationary coil is called stator. The moving magnet is called rotor. The running water or fuels like, coal, oil or gas are used to run generators for producing electricity. In coal-fired electricity generation, the burning coal heats water in a boiler to produce steam. The steam pushes the blades of a turbine fixed at the lower end of the rotor shaft. As the rotor spins inside the stator, electric power is generated.