Advances in Steam Turbines for Modern Power Plants: The first steam turbine for power generation was designed and built by Sir Charles Algernon Parsons in 1884 in England.
Advances in Steam Turbines for Modern Power Plants
Advances in Steam Turbines for Modern Power Plants Hand book
Edited by
Tadashi Tanuma
Contents
- Part I Steam Turbine Cycles and Cycle Design Optimization
- Part II Steam Turbine Analysis, Measurement
- Part III Development of Materials, Blades and Important Parts of Steam Turbines
- Part IV Turbine Retrofitting and Advanced Applications in Power Generation
Introduction to steam turbines for power plants
- Features of steam turbines
The first steam turbine for power generation was designed and built by Sir Charles Algernon Parsons in 1884 in England. Steam turbines have been key components of electrical power generation since the 19th century and are one of the distinctive out comes of the industrial revolution. Steam turbines have played a major role in power-generation industries, upgrading technology innovations for more than 130 years, and they continue to do so today.
Steam turbines are turbomachinery prime movers in which stator blades acceler ate and swirl high-temperature and high-pressure steam provided from their boilers around their rotors, and rotating blades receive impulse forces and reaction forces from the accelerated and swirled steam, and the rotating blades transmit the torque generated by the steam forces to their rotors. A turbine stage consists of a pair of a stator blade row and a rotating blade row. There are many kinds of steam turbines, from single-stage turbines to multi-stage turbines that have 30 or more stages. Therefore, the capacity range of a single unit is very wide, from the hundreds-of kW class to the 1900-MW class, and the range of applications of steam turbines is also very wide.
Electric power generation is one of main applications of steam turbines. Since high-temperature and high-pressure inlet steam conditions increase efficiency, inlet steam pressures range from 24.1 to 31.0 MPa.g (mega Pascal plus atmospheric pres sure), and temperatures range from 593C to 600C in typical steam turbines for modern large-scale thermal power plants. Steam turbines under these steam condi tions are usually called ultra-supercritical (USC) pressure steam turbines. Unit power outputs of USC power plants typically range from 600 to 1100 MW for one turbine unit, because a large capacity for one unit is advantageous for turbine effi ciency. As a representative case of USC steam turbines, a steam turbine usually consists of one single-flow high-pressure (HP) turbine, one single-flow or double flow intermediate-pressure (IP) turbine, and two double-flow low-pressure (LP) tur bines with last-stage blades of 1 m or more in length because the steam volume flow, including extraction steam of the steam turbine outlet in a condenser vacuum condition, increases up to 2000-times that of the inlet. Figs. 1.1 and 1.2 show typi cal USC steam turbines for modern power plants.
Figure 1.1 700 MW class steam turbine in a large-capacity power plant. HP inlet steam :
24.1 MPa 593C, IP inlet steam: 593C.
Source: Courtesy from Toshiba Corporation and Hokuriku Electric Power Company.
 |
| Figure 1.1 700 MW class steam turbine in a large-capacity power |
Figure 1.2 1000 MW class steam turbine in a large-capacity power plant. HP inlet steam:
25.1 MPa 600C, IP inlet steam: 610C.
Source: Courtesy from Mitsubishi Hitachi Power Systems Ltd.
 |
Figure 1.2 1000 MW class steam turbine in a large-capacity power plant. HP inlet steam: 25.1 MPa 600C, IP inlet steam: 610C. Source: Courtesy from Mitsubishi Hitachi Power Systems Ltd. |
Roles of steam turbines in power generation
Electricity is the world’s fastest-growing form of end-use energy consumption, as it has been for many decades. World electricity generation is projected to increase by a factor of 1.7 by 2040, from 21.6 trillion kilowatt-hours (kWh) in 2012 to 25.8 trillion kWh in 2020 and 36.5 trillion kWh in 2040. An important factor in electricity demand growth is economic growth, especially among the emerging non Organization for Economic Cooperation and Development (non-OECD) countries [1].
Power systems have continued to evolve in order to supply enough electricity into this increasing world market.
Power generation methods can be categorized by fuel as thermal (coal, natural gas, and petroleum), nuclear, and renewable (hydro, wind, biomass, geothermal, solar photovoltaics (PVs), and solar thermal). Steam turbines are widely used in coal-fired, natural gas-fired combined, nuclear, geothermal, and solar thermal power plants.
Fig ( 3 ) shows the world power generation of steam turbine power plants calcu lated using world net electricity generation by fuel [1, 2] and an assumption of a power plant configuration ratio by fuel (power generation ratio of steam turbines, gas turbines, hydro turbines, wind turbines, PVs, and others, by each fuel). The data for 2007 and 2012 are factual, while the data for 20202040 are forecasts of demand. The electricity generation of steam turbine power plants was 12.1 trillion
0 Comments