The generation of electricity is most commonly achieved by converting chemical energy in fuels or the flowing energy of wind, water, or steam into electrical energy, using a mechanical turbine connected to a generator. The force of the fluid causes the turbine to rotate, which in turn rotates the magnetic field inside the generator to produce electricity.
First, let's take a quick look at how this happens in a typical power plant. Then we'll explore each part of the process in more detail. And finally, we'll review how electric utilities manage and dispatch the power from their generating plants to meet customers' needs.
Typically, a fuel such as coal or oil is burned in a boiler to produce steam. The chemical energy in the fuel becomes heat energy as it burns, forming hot gases. To help protect the environment, these gases are cleaned by special equipment before they are released through the stack.
The steam, under great pressure, rushes through pipes and valves and turns the steam turbine at high speed. The turbine is made up of blades on a shaft and is driven by the steam like wind drives a windmill. Heat energy in the steam is converted to mechanical energy by the turbine.
When the steam leaves the turbine it goes to the condenser. Water from a nearby source is used in the condenser to cool the steam back to water. The water is sent back to boiler to become steam again.
The rotor in the generator is turned by the shaft from the turbine and electricity is produced. The mechanical energy produced in the turbine is changed to electrical energy in the generator.