In a steam turbine, hot water vapours flow from jets onto a rotor having several propeller-type shovel blades. There is a high pressure in front of the turbine, while a low pressure is maintained at the back. As a result, the steam shoots at high speed through the turbine transferring its energy to the rotor. The movement of the turbine is converted into electrical energy, through generators. Steam turbines are used mainly in coal-fired engines and nuclear power plants. The turbines of large power plants are up to 6o m long and weigh several hundred tons. Several rotors are connected in them one after the other.
