The steam turbine is used to drive an electric generator. A steam turbine is a rotary heat engine that converts the kinetic and thermal energy of flowing steam into mechanical rotary motion transmitted by a mechanical shaft. The turbine consists of one or several sections. Propeller wheels, a part of the machine stator, are called distribution wheels. The others, which are connected to the rotating shaft of the machine, are called impellers and, together with the shaft, form the machine rotor. Large steam turbines are usually divided into several sections– high-pressure and low-pressure, or even medium-pressure. Steam pressure and temperature in a BWR power plant are low compared to a modern coal-fired power plant and the steam turbine is generally very large. Because the steam is exposed to the core, there is some radioactive contamination of the turbines but this is short-lived and turbines can normally be accessed soon after shutdown.
