The turbine serves as the prime mover, meaning it generates the mechanical energy required for electricity production. It can be driven by various sources, including steam, natural gas, or water, depending on the power plant type. In thermal power plants (e.g., coal, natural gas), a boiler generates steam that is directed at high pressure and temperature towards the turbine blades, causing them to spin rapidly. In hydroelectric plants, the kinetic energy of flowing or falling water drives the turbine.
As the turbine spins, it rotates a shaft connected to the generator. The generator is essentially a rotating electrical machine that converts the mechanical energy from the spinning shaft into electrical energy. Inside the generator, the rotating shaft carries a set of coils known as the armature, which moves within a stationary set of coils called the stator. This relative motion induces an electric current in the stator coils due to the principles of electromagnetic induction. The alternating current (AC) produced by the generator is then sent to transformers to adjust the voltage levels and is often converted to direct current (DC) before being distributed to consumers.
