A power station , also referred to as a power plant and sometimes generating station or generating plant , is an industrial facility for the generation of electric power . Power stations are generally connected to an electrical grid .
98-497: The GRES-2 Power Station (or Power Station Ekibastuz ) is a coal-fueled power generating station in Ekibastuz , Kazakhstan. It is located close to Solnechny , by lake Shandaksor . The ashes of the station are dumped into nearby lake Karasor . GRES -2, commissioned in 1987, has an installed capacity of 1,000 MWe and has the world's tallest flue-gas stack at 419.7 metres (1,377 ft) tall. The reinforced concrete chimney
196-447: A magnetic field and a conductor creates an electric current . The energy source harnessed to turn the generator varies widely. Most power stations in the world burn fossil fuels such as coal , oil , and natural gas to generate electricity. Low-carbon power sources include nuclear power , and use of renewables such as solar , wind , geothermal , and hydroelectric . In early 1871 Belgian inventor Zénobe Gramme invented
294-579: A transformer to step up voltage for long-distance transmission and then stepped it back down for indoor lighting, a more efficient and less expensive system which is similar to modern systems. The war of the currents eventually resolved in favor of AC distribution and utilization, although some DC systems persisted to the end of the 20th century. DC systems with a service radius of a mile (kilometer) or so were necessarily smaller, less efficient of fuel consumption, and more labor-intensive to operate than much larger central AC generating stations. AC systems used
392-420: A byproduct of the useful electrical energy produced. The amount of waste heat energy equals or exceeds the amount of energy converted into useful electricity . Gas-fired power plants can achieve as much as 65% conversion efficiency, while coal and oil plants achieve around 30–49%. The waste heat produces a temperature rise in the atmosphere, which is small compared to that produced by greenhouse-gas emissions from
490-497: A closed space (e.g., combustion chamber , firebox , furnace). In the case of model or toy steam engines and a few full scale cases, the heat source can be an electric heating element . Boilers are pressure vessels that contain water to be boiled, and features that transfer the heat to the water as effectively as possible. The two most common types are: Fire-tube boilers were the main type used for early high-pressure steam (typical steam locomotive practice), but they were to
588-423: A common four-way rotary valve connected directly to a steam boiler. The next major step occurred when James Watt developed (1763–1775) an improved version of Newcomen's engine, with a separate condenser . Boulton and Watt 's early engines used half as much coal as John Smeaton 's improved version of Newcomen's. Newcomen's and Watt's early engines were "atmospheric". They were powered by air pressure pushing
686-438: A flywheel and crankshaft to provide rotative motion from an improved Newcomen engine. In 1720, Jacob Leupold described a two-cylinder high-pressure steam engine. The invention was published in his major work "Theatri Machinarum Hydraulicarum". The engine used two heavy pistons to provide motion to a water pump. Each piston was raised by the steam pressure and returned to its original position by gravity. The two pistons shared
784-427: A generator powerful enough to produce power on a commercial scale for industry. In 1878, a hydroelectric power station was designed and built by William, Lord Armstrong at Cragside , England . It used water from lakes on his estate to power Siemens dynamos . The electricity supplied power to lights, heating, produced hot water, ran an elevator as well as labor-saving devices and farm buildings. In January 1882
882-423: A given cylinder size than previous engines and could be made small enough for transport applications. Thereafter, technological developments and improvements in manufacturing techniques (partly brought about by the adoption of the steam engine as a power source) resulted in the design of more efficient engines that could be smaller, faster, or more powerful, depending on the intended application. The Cornish engine
980-425: A hydroelectric power station water flows through turbines using hydropower to generate hydroelectricity . Power is captured from the gravitational force of water falling through penstocks to water turbines connected to generators . The amount of power available is a combination of height and water flow. A wide range of Dams may be built to raise the water level, and create a lake for storing water . Hydropower
1078-416: A large extent displaced by more economical water tube boilers in the late 19th century for marine propulsion and large stationary applications. Many boilers raise the temperature of the steam after it has left that part of the boiler where it is in contact with the water. Known as superheating it turns ' wet steam ' into ' superheated steam '. It avoids the steam condensing in the engine cylinders, and gives
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#17327806941031176-403: A lower reservoir to an upper reservoir. Because the pumping takes place "off peak", electricity is less valuable than at peak times. This less valuable "spare" electricity comes from uncontrolled wind power and base load power plants such as coal, nuclear and geothermal, which still produce power at night even though demand is very low. During daytime peak demand, when electricity prices are high,
1274-406: A material that enhances the mixing of the upflowing air and the down-flowing water. In areas with restricted water use, a dry cooling tower or directly air-cooled radiators may be necessary, since the cost or environmental consequences of obtaining make-up water for evaporative cooling would be prohibitive. These coolers have lower efficiency and higher energy consumption to drive fans, compared to
1372-409: A partial vacuum by condensing steam under a piston within a cylinder. It was employed for draining mine workings at depths originally impractical using traditional means, and for providing reusable water for driving waterwheels at factories sited away from a suitable "head". Water that passed over the wheel was pumped up into a storage reservoir above the wheel. In 1780 James Pickard patented the use of
1470-569: A pipe containing a heat transfer fluid, such as oil. The heated oil is then used to boil water into steam, which turns a turbine that drives an electrical generator. The central tower type of solar thermal power plant uses hundreds or thousands of mirrors, depending on size, to direct sunlight onto a receiver on top of a tower. The heat is used to produce steam to turn turbines that drive electrical generators. Wind turbines can be used to generate electricity in areas with strong, steady winds, sometimes offshore . Many different designs have been used in
1568-405: A piston into the partial vacuum generated by condensing steam, instead of the pressure of expanding steam. The engine cylinders had to be large because the only usable force acting on them was atmospheric pressure . Watt developed his engine further, modifying it to provide a rotary motion suitable for driving machinery. This enabled factories to be sited away from rivers, and accelerated
1666-592: A power station is nearly the maximum electrical power that the power station can produce. Some power plants are run at almost exactly their rated capacity all the time, as a non-load-following base load power plant , except at times of scheduled or unscheduled maintenance. However, many power plants usually produce much less power than their rated capacity. In some cases a power plant produces much less power than its rated capacity because it uses an intermittent energy source . Operators try to pull maximum available power from such power plants, because their marginal cost
1764-433: A set speed, because it would assume a new constant speed in response to load changes. The governor was able to handle smaller variations such as those caused by fluctuating heat load to the boiler. Also, there was a tendency for oscillation whenever there was a speed change. As a consequence, engines equipped only with this governor were not suitable for operations requiring constant speed, such as cotton spinning. The governor
1862-522: A significantly higher efficiency . In a steam engine, a piston or steam turbine or any other similar device for doing mechanical work takes a supply of steam at high pressure and temperature and gives out a supply of steam at lower pressure and temperature, using as much of the difference in steam energy as possible to do mechanical work. These "motor units" are often called 'steam engines' in their own right. Engines using compressed air or other gases differ from steam engines only in details that depend on
1960-414: A steam jet usually supplied from the boiler. Injectors became popular in the 1850s but are no longer widely used, except in applications such as steam locomotives. It is the pressurization of the water that circulates through the steam boiler that allows the water to be raised to temperatures well above 100 °C (212 °F) boiling point of water at one atmospheric pressure, and by that means to increase
2058-628: A steam rail locomotive was designed and constructed by steamboat pioneer John Fitch in the United States probably during the 1780s or 1790s. His steam locomotive used interior bladed wheels guided by rails or tracks. The first full-scale working railway steam locomotive was built by Richard Trevithick in the United Kingdom and, on 21 February 1804, the world's first railway journey took place as Trevithick's steam locomotive hauled 10 tones of iron, 70 passengers and five wagons along
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#17327806941032156-421: A steam turbine. Bioenergy can also be processed through a range of temperatures and pressures in gasification , pyrolysis or torrefaction reactions. Depending on the desired end product, these reactions create more energy-dense products ( syngas , wood pellets , biocoal ) that can then be fed into an accompanying engine to produce electricity at a much lower emission rate when compared with open burning. It
2254-643: A steam turbine. The combination of a "top" cycle and a "bottom" cycle produces higher overall efficiency than either cycle can attain alone. In 2018, Inter RAO UES and State Grid Archived 21 December 2021 at the Wayback Machine planned to build an 8-GW thermal power plant, which's the largest coal-fired power plant construction project in Russia . A prime mover is a machine that converts energy of various forms into energy of motion. Power plants that can be dispatched (scheduled) to provide energy to
2352-495: A system include: Non-dispatchable plants include such sources as wind and solar energy; while their long-term contribution to system energy supply is predictable, on a short-term (daily or hourly) base their energy must be used as available since generation cannot be deferred. Contractual arrangements ("take or pay") with independent power producers or system interconnections to other networks may be effectively non-dispatchable. All thermal power plants produce waste heat energy as
2450-612: A trio of locomotives, concluding with the Catch Me Who Can in 1808. Only four years later, the successful twin-cylinder locomotive Salamanca by Matthew Murray was used by the edge railed rack and pinion Middleton Railway . In 1825 George Stephenson built the Locomotion for the Stockton and Darlington Railway . This was the first public steam railway in the world and then in 1829, he built The Rocket which
2548-682: A turbine is spun creating energy. This method is being specifically studied by the Norwegian utility Statkraft, which has calculated that up to 25 TWh/yr would be available from this process in Norway. Statkraft has built the world's first prototype osmotic power plant on the Oslo fjord which was opened on 24 November 2009. In January 2014, however, Statkraft announced not to continue this pilot. Biomass energy can be produced from combustion of waste green material to heat water into steam and drive
2646-445: A typical wet, evaporative cooling tower. Power plants can use an air-cooled condenser, traditionally in areas with a limited or expensive water supply. Air-cooled condensers serve the same purpose as a cooling tower (heat dissipation) without using water. They consume additional auxiliary power and thus may have a higher carbon footprint compared to a traditional cooling tower. Electric companies often prefer to use cooling water from
2744-561: A very limited lift height and were prone to boiler explosions . Savery's engine was used in mines, pumping stations and supplying water to water wheels powering textile machinery. One advantage of Savery's engine was its low cost. Bento de Moura Portugal introduced an improvement of Savery's construction "to render it capable of working itself", as described by John Smeaton in the Philosophical Transactions published in 1751. It continued to be manufactured until
2842-473: A water pump for draining inundated mines. Frenchman Denis Papin did some useful work on the steam digester in 1679, and first used a piston to raise weights in 1690. The first commercial steam-powered device was a water pump, developed in 1698 by Thomas Savery . It used condensing steam to create a vacuum which raised water from below and then used steam pressure to raise it higher. Small engines were effective though larger models were problematic. They had
2940-487: A wide range of frequencies depending on the type of load; lighting load using higher frequencies, and traction systems and heavy motor load systems preferring lower frequencies. The economics of central station generation improved greatly when unified light and power systems, operating at a common frequency, were developed. The same generating plant that fed large industrial loads during the day, could feed commuter railway systems during rush hour and then serve lighting load in
3038-451: Is a heat engine that performs mechanical work using steam as its working fluid . The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder . This pushing force can be transformed by a connecting rod and crank into rotational force for work. The term "steam engine" is most commonly applied to reciprocating engines as just described, although some authorities have also referred to
Ekibastuz GRES-2 Power Station - Misplaced Pages Continue
3136-700: Is about 40 m (130 ft) taller than the Inco Superstack in Sudbury, Ontario , Canada. It is the tallest chimney ever built. The power station is the start of the Powerline Ekibastuz–Kokshetau and uses a transmission voltage of 1,150 kVAC, the highest transmission voltage in the world. The extension of this line to Chelyabinsk in Russia is also designed for 1,150 kV, but it currently operates at only 500 kV. About 3/4 of
3234-431: Is cylinder condensation and re-evaporation. The steam cylinder and adjacent metal parts/ports operate at a temperature about halfway between the steam admission saturation temperature and the saturation temperature corresponding to the exhaust pressure. As high-pressure steam is admitted into the working cylinder, much of the high-temperature steam is condensed as water droplets onto the metal surfaces, significantly reducing
3332-583: Is possible to store energy and produce electrical power at a later time as in pumped-storage hydroelectricity , thermal energy storage , flywheel energy storage , battery storage power station and so on. The world's largest form of storage for excess electricity, pumped-storage is a reversible hydroelectric plant. They are a net consumer of energy but provide storage for any source of electricity, effectively smoothing peaks and troughs in electricity supply and demand. Pumped storage plants typically use "spare" electricity during off peak periods to pump water from
3430-518: Is practically zero, but the available power varies widely—in particular, it may be zero during heavy storms at night. In some cases operators deliberately produce less power for economic reasons. The cost of fuel to run a load following power plant may be relatively high, and the cost of fuel to run a peaking power plant is even higher—they have relatively high marginal costs. Operators keep power plants turned off ("operational reserve") or running at minimum fuel consumption ("spinning reserve") most of
3528-465: Is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. Solar energy can be turned into electricity either directly in solar cells , or in a concentrating solar power plant by focusing
3626-399: Is then pumped back up to pressure and sent back to the boiler. A dry-type cooling tower is similar to an automobile radiator and is used in locations where water is costly. Waste heat can also be ejected by evaporative (wet) cooling towers, which use a secondary external water circuit that evaporates some of flow to the air. River boats initially used a jet condenser in which cold water from
3724-410: Is used intermittently (peak load). Steam turbines generally operate at higher efficiency when operated at full capacity. Besides use of reject heat for process or district heating, one way to improve overall efficiency of a power plant is to combine two different thermodynamic cycles in a combined cycle plant. Most commonly, exhaust gases from a gas turbine are used to generate steam for a boiler and
3822-542: Is vented up the chimney so as to increase the draw on the fire, which greatly increases engine power, but reduces efficiency. Sometimes the waste heat from the engine is useful itself, and in those cases, very high overall efficiency can be obtained. Steam engines in stationary power plants use surface condensers as a cold sink. The condensers are cooled by water flow from oceans, rivers, lakes, and often by cooling towers which evaporate water to provide cooling energy removal. The resulting condensed hot water ( condensate ),
3920-697: The Roscoe Wind Farm is the largest onshore wind farm in the world, producing 8000 MW of power, followed by the Zhang Jiakou (3000 MW). As of January 2022, the Hornsea Wind Farm in United Kingdom is the largest offshore wind farm in the world at 1218 MW, followed by Walney Wind Farm in United Kingdom at 1026 MW. In 2021, the worldwide installed capacity of power plants increased by 347 GW. Solar and wind power plant capacities rose by 80% in one year. As of 2022 ,
4018-468: The Rumford Medal , the committee said that "no one invention since Watt's time has so enhanced the efficiency of the steam engine". In addition to using 30% less steam, it provided more uniform speed due to variable steam cut off, making it well suited to manufacturing, especially cotton spinning. The first experimental road-going steam-powered vehicles were built in the late 18th century, but it
Ekibastuz GRES-2 Power Station - Misplaced Pages Continue
4116-488: The largest photovoltaic (PV) power plants in the world are led by Bhadla Solar Park in India, rated at 2245 MW. Solar thermal power stations in the U.S. have the following output: Large coal-fired, nuclear, and hydroelectric power stations can generate hundreds of megawatts to multiple gigawatts. Some examples: Gas turbine power plants can generate tens to hundreds of megawatts. Some examples: The rated capacity of
4214-399: The piston or turbine machinery alone, as in the beam engine and stationary steam engine . As noted, steam-driven devices such as the aeolipile were known in the first century AD, and there were a few other uses recorded in the 16th century. In 1606 Jerónimo de Ayanz y Beaumont patented his invention of the first steam-powered water pump for draining mines. Thomas Savery is considered
4312-439: The second law of thermodynamics ; therefore, there is always heat lost to the environment. If this loss is employed as useful heat, for industrial processes or district heating , the power plant is referred to as a cogeneration power plant or CHP (combined heat-and-power) plant. In countries where district heating is common, there are dedicated heat plants called heat-only boiler stations . An important class of power stations in
4410-567: The steam turbine and devices such as Hero's aeolipile as "steam engines". The essential feature of steam engines is that they are external combustion engines , where the working fluid is separated from the combustion products. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle . In general usage, the term steam engine can refer to either complete steam plants (including boilers etc.), such as railway steam locomotives and portable engines , or may refer to
4508-626: The tramway from the Pen-y-darren ironworks, near Merthyr Tydfil to Abercynon in south Wales . The design incorporated a number of important innovations that included using high-pressure steam which reduced the weight of the engine and increased its efficiency. Trevithick visited the Newcastle area later in 1804 and the colliery railways in north-east England became the leading centre for experimentation and development of steam locomotives. Trevithick continued his own experiments using
4606-514: The 1860s to the 1920s. Steam road vehicles were used for many applications. In the 20th century, the rapid development of internal combustion engine technology led to the demise of the steam engine as a source of propulsion of vehicles on a commercial basis, with relatively few remaining in use beyond the Second World War . Many of these vehicles were acquired by enthusiasts for preservation, and numerous examples are still in existence. In
4704-562: The 1960s, the air pollution problems in California gave rise to a brief period of interest in developing and studying steam-powered vehicles as a possible means of reducing the pollution. Apart from interest by steam enthusiasts, the occasional replica vehicle, and experimental technology, no steam vehicles are in production at present. Near the end of the 19th century, compound engines came into widespread use. Compound engines exhausted steam into successively larger cylinders to accommodate
4802-490: The 20th century central stations became larger, using higher steam pressures to provide greater efficiency, and relying on interconnections of multiple generating stations to improve reliability and cost. High-voltage AC transmission allowed hydroelectric power to be conveniently moved from distant waterfalls to city markets. The advent of the steam turbine in central station service, around 1906, allowed great expansion of generating capacity. Generators were no longer limited by
4900-408: The 20th century, where their efficiency, higher speed appropriate to generator service, and smooth rotation were advantages. Today most electric power is provided by steam turbines. In the United States, 90% of the electric power is produced in this way using a variety of heat sources. Steam turbines were extensively applied for propulsion of large ships throughout most of the 20th century. Although
4998-572: The Drakensberg, Ingula Pumped Storage Scheme . The power generated by a power station is measured in multiples of the watt , typically megawatts (10 watts) or gigawatts (10 watts). Power stations vary greatly in capacity depending on the type of power plant and on historical, geographical and economic factors. The following examples offer a sense of the scale. Many of the largest operational onshore wind farms are located in China. As of 2022,
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#17327806941035096-493: The Middle East uses by-product heat for the desalination of water. The efficiency of a thermal power cycle is limited by the maximum working fluid temperature produced. The efficiency is not directly a function of the fuel used. For the same steam conditions, coal-, nuclear- and gas power plants all have the same theoretical efficiency. Overall, if a system is on constantly (base load) it will be more efficient than one that
5194-566: The United States, Ferranti and Charles Hesterman Merz in UK, and many others . 2021 world electricity generation by source. Total generation was 28 petawatt-hours . In thermal power stations, mechanical power is produced by a heat engine that transforms thermal energy , often from combustion of a fuel , into rotational energy. Most thermal power stations produce steam, so they are sometimes called steam power stations. Not all thermal energy can be transformed into mechanical power, according to
5292-610: The amount of work obtained per unit of fuel consumed. By the 19th century, stationary steam engines powered the factories of the Industrial Revolution . Steam engines replaced sails for ships on paddle steamers , and steam locomotives operated on the railways. Reciprocating piston type steam engines were the dominant source of power until the early 20th century. The efficiency of stationary steam engine increased dramatically until about 1922. The highest Rankine Cycle Efficiency of 91% and combined thermal efficiency of 31%
5390-475: The atmosphere or into a condenser. As steam expands in passing through a high-pressure engine, its temperature drops because no heat is being added to the system; this is known as adiabatic expansion and results in steam entering the cylinder at high temperature and leaving at lower temperature. This causes a cycle of heating and cooling of the cylinder with every stroke, which is a source of inefficiency. The dominant efficiency loss in reciprocating steam engines
5488-404: The boiler and engine in separate buildings some distance apart. For portable or mobile use, such as steam locomotives , the two are mounted together. The widely used reciprocating engine typically consisted of a cast-iron cylinder, piston, connecting rod and beam or a crank and flywheel, and miscellaneous linkages. Steam was alternately supplied and exhausted by one or more valves. Speed control
5586-552: The cooling machinery. These screens are only partially effective and as a result billions of fish and other aquatic organisms are killed by power plants each year. For example, the cooling system at the Indian Point Energy Center in New York kills over a billion fish eggs and larvae annually. A further environmental impact is that aquatic organisms which adapt to the warmer discharge water may be injured if
5684-401: The efficiency of the steam cycle. For safety reasons, nearly all steam engines are equipped with mechanisms to monitor the boiler, such as a pressure gauge and a sight glass to monitor the water level. Many engines, stationary and mobile, are also fitted with a governor to regulate the speed of the engine without the need for human interference. The most useful instrument for analyzing
5782-411: The energy carried by ocean waves , tides , salinity , and ocean temperature differences . The movement of water in the world's oceans creates a vast store of kinetic energy , or energy in motion. This energy can be harnessed to generate electricity to power homes, transport and industries. The term marine energy encompasses both wave power —power from surface waves, and tidal power —obtained from
5880-448: The energy produced by GRES-2 was exported to Russia. Fifty percent of GRES-2 shares are owned by Inter RAO UES , and fifty percent by Kazakhstan's government . The planned capacity of 4,000 MWe is to be provided by eight equal units, 500 MWe each. Power station Many power stations contain one or more generators , rotating machine that converts mechanical power into three-phase electric power . The relative motion between
5978-409: The evening, thus improving the system load factor and reducing the cost of electrical energy overall. Many exceptions existed, generating stations were dedicated to power or light by the choice of frequency, and rotating frequency changers and rotating converters were particularly common to feed electric railway systems from the general lighting and power network. Throughout the first few decades of
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#17327806941036076-463: The higher volumes at reduced pressures, giving improved efficiency. These stages were called expansions, with double- and triple-expansion engines being common, especially in shipping where efficiency was important to reduce the weight of coal carried. Steam engines remained the dominant source of power until the early 20th century, when advances in the design of the steam turbine , electric motors , and internal combustion engines gradually resulted in
6174-402: The inventor of the first commercially used steam powered device, a steam pump that used steam pressure operating directly on the water. The first commercially successful engine that could transmit continuous power to a machine was developed in 1712 by Thomas Newcomen . James Watt made a critical improvement in 1764, by removing spent steam to a separate vessel for condensation, greatly improving
6272-406: The kinetic energy of large bodies of moving water. Offshore wind power is not a form of marine energy, as wind power is derived from the wind , even if the wind turbines are placed over water. The oceans have a tremendous amount of energy and are close to many if not most concentrated populations. Ocean energy has the potential of providing a substantial amount of new renewable energy around
6370-518: The largest power plants terawatt-hours (TW·h). It includes the electricity used in the plant auxiliaries and in the transformers. Net generation is the amount of electricity generated by a power plant that is transmitted and distributed for consumer use. Net generation is less than the total gross power generation as some power produced is consumed within the plant itself to power auxiliary equipment such as pumps , motors and pollution control devices. Thus Steam engine A steam engine
6468-429: The late 18th century. At least one engine was still known to be operating in 1820. The first commercially successful engine that could transmit continuous power to a machine was the atmospheric engine , invented by Thomas Newcomen around 1712. It improved on Savery's steam pump, using a piston as proposed by Papin. Newcomen's engine was relatively inefficient, and mostly used for pumping water. It worked by creating
6566-425: The light to run a heat engine. A solar photovoltaic power plant converts sunlight into direct current electricity using the photoelectric effect . Inverters change the direct current into alternating current for connection to the electrical grid. This type of plant does not use rotating machines for energy conversion. Solar thermal power plants use either parabolic troughs or heliostats to direct sunlight onto
6664-399: The nature of the gas although compressed air has been used in steam engines without change. As with all heat engines, the majority of primary energy must be emitted as waste heat at relatively low temperature. The simplest cold sink is to vent the steam to the environment. This is often used on steam locomotives to avoid the weight and bulk of condensers. Some of the released steam
6762-479: The ocean or a lake, river, or cooling pond instead of a cooling tower. This single pass or once-through cooling system can save the cost of a cooling tower and may have lower energy costs for pumping cooling water through the plant's heat exchangers . However, the waste heat can cause thermal pollution as the water is discharged. Power plants using natural bodies of water for cooling are designed with mechanisms such as fish screens , to limit intake of organisms into
6860-518: The pace of the Industrial Revolution. The meaning of high pressure, together with an actual value above ambient, depends on the era in which the term was used. For early use of the term Van Reimsdijk refers to steam being at a sufficiently high pressure that it could be exhausted to atmosphere without reliance on a vacuum to enable it to perform useful work. Ewing 1894 , p. 22 states that Watt's condensing engines were known, at
6958-557: The past, but almost all modern turbines being produced today use a three-bladed, upwind design. Grid-connected wind turbines now being built are much larger than the units installed during the 1970s. They thus produce power more cheaply and reliably than earlier models. With larger turbines (on the order of one megawatt), the blades move more slowly than older, smaller, units, which makes them less visually distracting and safer for birds. Marine energy or marine power (also sometimes referred to as ocean energy or ocean power ) refers to
7056-456: The performance of steam engines is the steam engine indicator. Early versions were in use by 1851, but the most successful indicator was developed for the high speed engine inventor and manufacturer Charles Porter by Charles Richard and exhibited at London Exhibition in 1862. The steam engine indicator traces on paper the pressure in the cylinder throughout the cycle, which can be used to spot various problems and calculate developed horsepower. It
7154-456: The piston axis in vertical position. In time the horizontal arrangement became more popular, allowing compact, but powerful engines to be fitted in smaller spaces. The acme of the horizontal engine was the Corliss steam engine , patented in 1849, which was a four-valve counter flow engine with separate steam admission and exhaust valves and automatic variable steam cutoff. When Corliss was given
7252-674: The plant shuts down in cold weather . Water consumption by power stations is a developing issue. In recent years, recycled wastewater, or grey water , has been used in cooling towers. The Calpine Riverside and the Calpine Fox power stations in Wisconsin as well as the Calpine Mankato power station in Minnesota are among these facilities. Power stations can generate electrical energy from renewable energy sources. In
7350-406: The power themselves, in which case the generation output is classified into gross generation , and net generation . Gross generation or gross electric output is the total amount of electricity generated by a power plant over a specific period of time. It is measured at the generating terminal and is measured in kilowatt-hours (kW·h), megawatt-hours (MW·h), gigawatt-hours (GW·h) or for
7448-559: The power transmission of belts or the relatively slow speed of reciprocating engines, and could grow to enormous sizes. For example, Sebastian Ziani de Ferranti planned what would have reciprocating steam engine ever built for a proposed new central station, but scrapped the plans when turbines became available in the necessary size. Building power systems out of central stations required combinations of engineering skill and financial acumen in equal measure. Pioneers of central station generation include George Westinghouse and Samuel Insull in
7546-406: The reciprocating steam engine is no longer in widespread commercial use, various companies are exploring or exploiting the potential of the engine as an alternative to internal combustion engines. There are two fundamental components of a steam plant: the boiler or steam generator , and the "motor unit", referred to itself as a "steam engine". Stationary steam engines in fixed buildings may have
7644-417: The replacement of reciprocating (piston) steam engines, with merchant shipping relying increasingly upon diesel engines , and warships on the steam turbine. As the development of steam engines progressed through the 18th century, various attempts were made to apply them to road and railway use. In 1784, William Murdoch , a Scottish inventor, built a model steam road locomotive. An early working model of
7742-578: The river is injected into the exhaust steam from the engine. Cooling water and condensate mix. While this was also applied for sea-going vessels, generally after only a few days of operation the boiler would become coated with deposited salt, reducing performance and increasing the risk of a boiler explosion. Starting about 1834, the use of surface condensers on ships eliminated fouling of the boilers, and improved engine efficiency. Evaporated water cannot be used for subsequent purposes (other than rain somewhere), whereas river water can be re-used. In all cases,
7840-728: The road, which was the monopoly of the gas companies. The customers included the City Temple and the Old Bailey . Another important customer was the Telegraph Office of the General Post Office , but this could not be reached through the culverts. Johnson arranged for the supply cable to be run overhead, via Holborn Tavern and Newgate . In September 1882 in New York, the Pearl Street Station
7938-777: The same power plant. Natural draft wet cooling towers at many nuclear power plants and large fossil-fuel-fired power plants use large hyperboloid chimney -like structures (as seen in the image at the right) that release the waste heat to the ambient atmosphere by the evaporation of water. However, the mechanical induced-draft or forced-draft wet cooling towers in many large thermal power plants, nuclear power plants, fossil-fired power plants, petroleum refineries , petrochemical plants , geothermal , biomass and waste-to-energy plants use fans to provide air movement upward through down coming water and are not hyperboloid chimney-like structures. The induced or forced-draft cooling towers are typically rectangular, box-like structures filled with
8036-412: The steam plant boiler feed water, which must be kept pure, is kept separate from the cooling water or air. Most steam boilers have a means to supply water whilst at pressure, so that they may be run continuously. Utility and industrial boilers commonly use multi-stage centrifugal pumps ; however, other types are used. Another means of supplying lower-pressure boiler feed water is an injector , which uses
8134-512: The storage is used for peaking power , where water in the upper reservoir is allowed to flow back to a lower reservoir through a turbine and generator. Unlike coal power stations, which can take more than 12 hours to start up from cold, a hydroelectric generator can be brought into service in a few minutes, ideal to meet a peak load demand. Two substantial pumped storage schemes are in South Africa, Palmiet Pumped Storage Scheme and another in
8232-489: The temperature of the steam above its saturated vapour point, and various mechanisms to increase the draft for fireboxes. When coal is used, a chain or screw stoking mechanism and its drive engine or motor may be included to move the fuel from a supply bin (bunker) to the firebox. The heat required for boiling the water and raising the temperature of the steam can be derived from various sources, most commonly from burning combustible materials with an appropriate supply of air in
8330-482: The time, as low pressure compared to high pressure, non-condensing engines of the same period. Watt's patent prevented others from making high pressure and compound engines. Shortly after Watt's patent expired in 1800, Richard Trevithick and, separately, Oliver Evans in 1801 introduced engines using high-pressure steam; Trevithick obtained his high-pressure engine patent in 1802, and Evans had made several working models before then. These were much more powerful for
8428-448: The time. Operators feed more fuel into load following power plants only when the demand rises above what lower-cost plants (i.e., intermittent and base load plants) can produce, and then feed more fuel into peaking power plants only when the demand rises faster than the load following power plants can follow. Not all of the generated power of a plant is necessarily delivered into a distribution system. Power plants typically also use some of
8526-565: The world's first public coal-fired power station , the Edison Electric Light Station , was built in London, a project of Thomas Edison organized by Edward Johnson . A Babcock & Wilcox boiler powered a 93 kW (125 horsepower) steam engine that drove a 27-tonne (27-long-ton) generator. This supplied electricity to premises in the area that could be reached through the culverts of the viaduct without digging up
8624-415: The world. Salinity gradient energy is called pressure-retarded osmosis. In this method, seawater is pumped into a pressure chamber that is at a pressure lower than the difference between the pressures of saline water and fresh water. Freshwater is also pumped into the pressure chamber through a membrane, which increases both the volume and pressure of the chamber. As the pressure differences are compensated,
8722-627: Was demonstrated and published in 1921 and 1928. Advances in the design of electric motors and internal combustion engines resulted in the gradual replacement of steam engines in commercial usage. Steam turbines replaced reciprocating engines in power generation, due to lower cost, higher operating speed, and higher efficiency. Note that small scale steam turbines are much less efficient than large ones. As of 2023 , large reciprocating piston steam engines are still being manufactured in Germany. As noted, one recorded rudimentary steam-powered engine
8820-546: Was developed by Trevithick and others in the 1810s. It was a compound cycle engine that used high-pressure steam expansively, then condensed the low-pressure steam, making it relatively efficient. The Cornish engine had irregular motion and torque through the cycle, limiting it mainly to pumping. Cornish engines were used in mines and for water supply until the late 19th century. Early builders of stationary steam engines considered that horizontal cylinders would be subject to excessive wear. Their engines were therefore arranged with
8918-450: Was either automatic, using a governor, or by a manual valve. The cylinder casting contained steam supply and exhaust ports. Engines equipped with a condenser are a separate type than those that exhaust to the atmosphere. Other components are often present; pumps (such as an injector ) to supply water to the boiler during operation, condensers to recirculate the water and recover the latent heat of vaporisation, and superheaters to raise
9016-531: Was entered in and won the Rainhill Trials . The Liverpool and Manchester Railway opened in 1830 making exclusive use of steam power for both passenger and freight trains. Steam locomotives continued to be manufactured until the late twentieth century in places such as China and the former East Germany (where the DR Class 52.80 was produced). The final major evolution of the steam engine design
9114-454: Was established by Edison to provide electric lighting in the lower Manhattan Island area. The station ran until destroyed by fire in 1890. The station used reciprocating steam engines to turn direct-current generators. Because of the DC distribution, the service area was small, limited by voltage drop in the feeders. In 1886 George Westinghouse began building an alternating current system that used
9212-411: Was improved over time and coupled with variable steam cut off, good speed control in response to changes in load was attainable near the end of the 19th century. In a simple engine, or "single expansion engine" the charge of steam passes through the entire expansion process in an individual cylinder, although a simple engine may have one or more individual cylinders. It is then exhausted directly into
9310-479: Was not until after Richard Trevithick had developed the use of high-pressure steam, around 1800, that mobile steam engines became a practical proposition. The first half of the 19th century saw great progress in steam vehicle design, and by the 1850s it was becoming viable to produce them on a commercial basis. This progress was dampened by legislation which limited or prohibited the use of steam-powered vehicles on roads. Improvements in vehicle technology continued from
9408-496: Was routinely used by engineers, mechanics and insurance inspectors. The engine indicator can also be used on internal combustion engines. See image of indicator diagram below (in Types of motor units section). The centrifugal governor was adopted by James Watt for use on a steam engine in 1788 after Watt's partner Boulton saw one on the equipment of a flour mill Boulton & Watt were building. The governor could not actually hold
9506-763: Was the aeolipile described by Hero of Alexandria , a Hellenistic mathematician and engineer in Roman Egypt during the first century AD. In the following centuries, the few steam-powered engines known were, like the aeolipile, essentially experimental devices used by inventors to demonstrate the properties of steam. A rudimentary steam turbine device was described by Taqi al-Din in Ottoman Egypt in 1551 and by Giovanni Branca in Italy in 1629. The Spanish inventor Jerónimo de Ayanz y Beaumont received patents in 1606 for 50 steam-powered inventions, including
9604-438: Was the use of steam turbines starting in the late part of the 19th century. Steam turbines are generally more efficient than reciprocating piston type steam engines (for outputs above several hundred horsepower), have fewer moving parts, and provide rotary power directly instead of through a connecting rod system or similar means. Steam turbines virtually replaced reciprocating engines in electricity generating stations early in
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