Steam turbine

A steam turbine or steam turbine engine is a machine or heat engine that extracts thermal energy from pressurized steam and uses it to do mechanical work utilising a rotating output shaft. Its modern form was invented by Sir Charles Parsons in 1884 and revolutionized marine propulsion and navigation. Fabrication of a modern steam turbine involves advanced metalwork to form high-grade steel alloys into precision parts using technologies that first became available in the 20th century; continued advances in the durability and efficiency of steam turbines remains central to the energy economics of the 21st century. The largest steam turbine ever built is the 1,770 MW Arabelle steam turbine built by Arabelle Solutions (previously GE Steam Power), two units of which will be installed at Hinkley Point C Nuclear Power Station, England.

The steam turbine is a form of heat engine that derives much of its improvement in thermodynamic efficiency from the use of multiple stages in the expansion of the steam, which results in a closer approach to the ideal reversible expansion process. Because the turbine generates rotary motion, it can be coupled to a generator to harness its motion into electricity. Such turbogenerators are the core of thermal power stations which can be fueled by fossil fuels, nuclear fuels, geothermal, or solar energy. About 42% of all electricity generation in the United States in 2022 was by the use of steam turbines. Technical challenges include rotor imbalance, vibration, bearing wear, and uneven expansion (various forms of thermal shock).

History

The first device that may be classified as a reaction steam turbine was little more than a toy, the classic Aeolipile, described in the 1st century by Hero of Alexandria in Roman Egypt.