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85-693: The son of a Galloway quarryman, he joined the civil service at the age of 17, rising through the ranks of the Civil Service Clerical Association . He became a leader of the "Sauchiehall Street Mafia", a left-wing association credited with helping radicalise the civil service unions in the 1960s. In 1983, Christie stood unsuccessfully to become the General Secretary of the National Association of Local Government Officers . Away from politics, Christie

170-745: A greenhouse gas . According to the World Commission on Dams report, where the reservoir is large compared to the generating capacity (less than 100 watts per square metre of surface area) and no clearing of the forests in the area was undertaken prior to impoundment of the reservoir, greenhouse gas emissions from the reservoir may be higher than those of a conventional oil-fired thermal generation plant. In boreal reservoirs of Canada and Northern Europe, however, greenhouse gas emissions are typically only 2% to 8% of any kind of conventional fossil-fuel thermal generation. A new class of underwater logging operation that targets drowned forests can mitigate

255-463: A low-head hydro power plant with hydrostatic head of few meters to few tens of meters can be classified either as an SHP or an LHP. The other distinction between SHP and LHP is the degree of the water flow regulation: a typical SHP primarily uses the natural water discharge with very little regulation in comparison to an LHP. Therefore, the term SHP is frequently used as a synonym for the run-of-the-river power plant . The largest power producers in

340-580: A whodunit by Dorothy L. Sayers , initially published in the US as Suspicious Characters , sees Lord Peter Wimsey , on holiday in Kirkcudbright , investigating the death of an artist living at Gatehouse of Fleet ; the book contains some remarkable descriptions of the countryside. S R Crockett , a bestselling writer of historical romances active before the First World War, set several novels in

425-534: A church or monastery at Whithorn , Wigtownshire , which remained an important place of pilgrimage until the Reformation . A Brythonic speaking kingdom dominated Galloway until the late 7th century when it was absorbed by the English kingdom of Bernicia . English prevalence was supplanted by Britons and Norse-Gaelic ( Gall-Ghàidheal ) peoples between the 9th and the 11th century. This can be seen in

510-536: A copy of the Wycliffe Bible was circulating in Galloway around 1520, and secret groups (proto-conventicles) gathered to hear a man named Alexander Gordon preach from it. With the end of the monasteries, the large ecclesiastical landholdings created under the medieval Lordship of Galloway were broken up amongst hundreds of small landowners. In the case of Dundrennan Abbey , much of the abbey's lands came into

595-581: A crannog, the Black Loch of Myrton site was later recharacterized as a "lochside village". Promontory forts are highly topographically-defined sites, which in Galloway generally occupy coastal promontories overlooking the Solway Firth. Investigation of one such site at Carghidown revealed a "sporadically occupied refuge" according to Toolis, who also notes that "hardly any promontory forts occupy strongly defensive locations or have immediate access to

680-426: A dam and reservoir is a flexible source, since the amount of electricity produced can be increased or decreased in seconds or minutes in response to varying electricity demand. Once a hydroelectric complex is constructed, it produces no direct waste, and almost always emits considerably less greenhouse gas than fossil fuel -powered energy plants. However, when constructed in lowland rainforest areas, where part of

765-421: A flood and fail. Changes in the amount of river flow will correlate with the amount of energy produced by a dam. Lower river flows will reduce the amount of live storage in a reservoir therefore reducing the amount of water that can be used for hydroelectricity. The result of diminished river flow can be power shortages in areas that depend heavily on hydroelectric power. The risk of flow shortage may increase as

850-477: A gradual incorporation of Galloway into Scotland. Scotland's legal system was administered as a system of three provinces, each with a justiciar (high official). The Justiciar of Galloway was one of these, along with justiciars for Lothian and "Scotia" (lands north of the Forth and Clyde). Additionally, Whithorn remained an important cultural centre; medieval kings of Scots made pilgrimages there. Folklore holds that

935-809: A large natural height difference between two waterways, such as a waterfall or mountain lake. A tunnel is constructed to take water from the high reservoir to the generating hall built in a cavern near the lowest point of the water tunnel and a horizontal tailrace taking water away to the lower outlet waterway. A simple formula for approximating electric power production at a hydroelectric station is: P = − η   ( m ˙ g   Δ h ) = − η   ( ( ρ V ˙ )   g   Δ h ) {\displaystyle P=-\eta \ ({\dot {m}}g\ \Delta h)=-\eta \ ((\rho {\dot {V}})\ g\ \Delta h)} where Efficiency

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1020-460: A large number of small landholders began to consolidate into larger estates. The Irish cattle trade increased until up to 10,000 head of cattle per year were being exported through this route in the year 1667. It was in this year that the importation of Irish cattle to England was banned. However, the importation of Scottish cattle was not banned; this created a new opportunity for Galloway landowners to profit from illicit Irish cattle. By this time,

1105-451: A larger amount of methane than those in temperate areas. Like other non-fossil fuel sources, hydropower also has no emissions of sulfur dioxide, nitrogen oxides, or other particulates. Reservoirs created by hydroelectric schemes often provide facilities for water sports , and become tourist attractions themselves. In some countries, aquaculture in reservoirs is common. Multi-use dams installed for irrigation support agriculture with

1190-618: A number of Iron Age and Roman period sites indicate the Scottish Southern Uplands as a possible ore source for the lead material, though it is unclear how early extraction of lead could have taken place in Galloway specifically. Metallurgical testing done on three lead beads recovered from the Carghidown site (dated to c.  360 BC–AD 60 ) indicated a closer affinity to the Southern Uplands than to

1275-556: A number of prominent individuals associated with the Stuart monarchy held lands in both Galloway and in Ulster, facilitating the illicit trade, which "may have been tolerated for political reasons". Many of these landowners were also Episcopalians . Galwegian Gaelic seems to have lasted longer than Gaelic in other parts of Lowland Scotland , and Margaret McMurray (d. 1760) of Carrick (outside modern Galloway) appears to have been

1360-647: A period of Scottish allegiance, a Galloway contingent followed David, King of Scots , in his invasion of England and led the attack in his defeat at the Battle of the Standard (1138). Alan died in 1234, leaving three daughters and an illegitimate son, Thomas ( Tomás mac Ailein ). Alexander II of Scotland , Galloway's suzerain, planned to divide Galloway between Alan's three daughters and their husbands (all Norman noblemen) and to exclude Thomas under Norman feudal law. However, Thomas considered himself Alan's heir under

1445-592: A positive risk adjusted return, unless appropriate risk management measures are put in place. While many hydroelectric projects supply public electricity networks, some are created to serve specific industrial enterprises. Dedicated hydroelectric projects are often built to provide the substantial amounts of electricity needed for aluminium electrolytic plants, for example. The Grand Coulee Dam switched to support Alcoa aluminium in Bellingham, Washington , United States for American World War II airplanes before it

1530-548: A relatively constant water supply. Large hydro dams can control floods, which would otherwise affect people living downstream of the project. Managing dams which are also used for other purposes, such as irrigation , is complicated. In 2021 the IEA called for "robust sustainability standards for all hydropower development with streamlined rules and regulations". Large reservoirs associated with traditional hydroelectric power stations result in submersion of extensive areas upstream of

1615-540: A result of climate change . One study from the Colorado River in the United States suggest that modest climate changes, such as an increase in temperature in 2 degree Celsius resulting in a 10% decline in precipitation, might reduce river run-off by up to 40%. Brazil in particular is vulnerable due to its heavy reliance on hydroelectricity, as increasing temperatures, lower water flow and alterations in

1700-825: A sample from the Isle of Man . The area around Whithorn, containing both the Carghidown and Rispain Camp sites, appears to have become a local power centre. The Carghidown site is located only a short distance to the east along the coast from St Ninian's Cave , while the Rispain Camp site is several miles inland. Following the start of the Roman conquest of Britain , the Roman general Gnaeus Julius Agricola campaigned northward, reaching Scotland around AD 79. A possible comment about "trackless wastes" may have referred to Galloway, but this

1785-448: A small TV/radio). Even smaller turbines of 200–300 W may power a few homes in a developing country with a drop of only 1 m (3 ft). A Pico-hydro setup is typically run-of-the-river , meaning that dams are not used, but rather pipes divert some of the flow, drop this down a gradient, and through the turbine before returning it to the stream. An underground power station is generally used at large facilities and makes use of

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1870-455: A source of low-cost renewable energy. Alternatively, small hydro projects may be built in isolated areas that would be uneconomic to serve from a grid, or in areas where there is no national electrical distribution network. Since small hydro projects usually have minimal reservoirs and civil construction work, they are seen as having a relatively low environmental impact compared to large hydro. This decreased environmental impact depends strongly on

1955-414: A start-up time of the order of a few minutes. Although battery power is quicker its capacity is tiny compared to hydro. It takes less than 10 minutes to bring most hydro units from cold start-up to full load; this is quicker than nuclear and almost all fossil fuel power. Power generation can also be decreased quickly when there is a surplus power generation. Hence the limited capacity of hydropower units

2040-581: A total of 1,500 terawatt-hours (TWh) of electrical energy in one full cycle" which was "about 170 times more energy than the global fleet of pumped storage hydropower plants". Battery storage capacity is not expected to overtake pumped storage during the 2020s. When used as peak power to meet demand, hydroelectricity has a higher value than baseload power and a much higher value compared to intermittent energy sources such as wind and solar. Hydroelectric stations have long economic lives, with some plants still in service after 50–100 years. Operating labor cost

2125-435: Is electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity , almost 4,210 TWh in 2023, which is more than all other renewable sources combined and also more than nuclear power . Hydropower can provide large amounts of low-carbon electricity on demand, making it a key element for creating secure and clean electricity supply systems. A hydroelectric power station that has

2210-452: Is hydroelectric power on a scale serving a small community or industrial plant. The definition of a small hydro project varies but a generating capacity of up to 10 megawatts (MW) is generally accepted as the upper limit. This may be stretched to 25 MW and 30 MW in Canada and the United States. Small hydro stations may be connected to conventional electrical distribution networks as

2295-525: Is a stub . You can help Misplaced Pages by expanding it . This biographical article about a trade unionist in the United Kingdom is a stub . You can help Misplaced Pages by expanding it . Galloway Galloway ( Scottish Gaelic : Gall-Ghàidhealaibh [ˈkal̪ˠaɣəl̪ˠu] ; Scots : Gallowa ; Latin : Gallovidia ) is a region in southwestern Scotland comprising the historic counties of Wigtownshire and Kirkcudbrightshire . It

2380-708: Is a great deal of good pasture. The northern part of Galloway is exceedingly rugged and forms the largest remaining wilderness in Britain south of the Highlands . This area is known as the Galloway Hills . Historically Galloway has been known both for horses and for cattle rearing, and milk and beef production are both still major industries. There is also substantial timber production and some fisheries . The combination of hills and high rainfall make Galloway ideal for hydroelectric power production, and

2465-536: Is administered as part of the council area of Dumfries and Galloway . A native or inhabitant of Galloway is called a Gallovidian. The region takes its name from the Gall-Gàidheil , or "stranger Gaels", a people of mixed Gaelic and Norse descent who seem to have settled here in the 10th century. Galloway is bounded by sea to the west and south, the Galloway Hills to the north, and the River Nith to

2550-635: Is also usually low, as plants are automated and have few personnel on site during normal operation. Where a dam serves multiple purposes, a hydroelectric station may be added with relatively low construction cost, providing a useful revenue stream to offset the costs of dam operation. It has been calculated that the sale of electricity from the Three Gorges Dam will cover the construction costs after 5 to 8 years of full generation. However, some data shows that in most countries large hydropower dams will be too costly and take too long to build to deliver

2635-470: Is highest in the winter when solar energy is at a minimum. Pico hydro is hydroelectric power generation of under 5 kW . It is useful in small, remote communities that require only a small amount of electricity. For example, the 1.1 kW Intermediate Technology Development Group Pico Hydro Project in Kenya supplies 57 homes with very small electric loads (e.g., a couple of lights and a phone charger, or

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2720-445: Is initially produced during construction of the project, and some methane is given off annually by reservoirs, hydro has one of the lowest lifecycle greenhouse gas emissions for electricity generation. The low greenhouse gas impact of hydroelectricity is found especially in temperate climates . Greater greenhouse gas emission impacts are found in the tropical regions because the reservoirs of power stations in tropical regions produce

2805-462: Is not an energy source, and appears as a negative number in listings. Run-of-the-river hydroelectric stations are those with small or no reservoir capacity, so that only the water coming from upstream is available for generation at that moment, and any oversupply must pass unused. A constant supply of water from a lake or existing reservoir upstream is a significant advantage in choosing sites for run-of-the-river. A tidal power station makes use of

2890-452: Is not generally used to produce base power except for vacating the flood pool or meeting downstream needs. Instead, it can serve as backup for non-hydro generators. The major advantage of conventional hydroelectric dams with reservoirs is their ability to store water at low cost for dispatch later as high value clean electricity. In 2021, the IEA estimated that the "reservoirs of all existing conventional hydropower plants combined can store

2975-410: Is often higher (that is, closer to 1) with larger and more modern turbines. Annual electric energy production depends on the available water supply. In some installations, the water flow rate can vary by a factor of 10:1 over the course of a year. Hydropower is a flexible source of electricity since stations can be ramped up and down very quickly to adapt to changing energy demands. Hydro turbines have

3060-657: Is thought that the Iron Age inhabitants of the Barsalloch Fort site were the Novantae people. The Rispain Camp site is also associated with the Novantae. In the west, the city of Rerigonium (literally 'very royal place'), shown on Ptolemy 's map of the world, is a strong contender for the site of Pen Rhionydd , referred to in the Welsh Triads as one of the 'three thrones of Britain' associated with

3145-684: Is unclear. The source of this comment is the version of Tacitus' Agricola which is contained in the Codex Aesinas . The Codex Aesinas is a composite work produced in the 15th century, which is based on a now-lost 9th century work, the Codex Hersfeldensis , which contained portions of the Agricola . The interpretation of "trackless wastes" is based on material thought to derive from the 9th century codex, with an original Latin in avia primum transgressus ("first crossing into

3230-679: The Bonneville Dam in 1937 and being recognized by the Flood Control Act of 1936 as the premier federal flood control agency. Hydroelectric power stations continued to become larger throughout the 20th century. Hydropower was referred to as "white coal". Hoover Dam 's initial 1,345 MW power station was the world's largest hydroelectric power station in 1936; it was eclipsed by the 6,809 MW Grand Coulee Dam in 1942. The Itaipu Dam opened in 1984 in South America as

3315-572: The Galloway Hydro Power scheme was begun in 1929. Since then, electricity generation has been a significant industry. More recently wind turbines have been installed at a number of locations on the watershed, and a large offshore wind-power plant is planned, increasing Galloway's 'green energy' production. It is thought that aspects of the Barsalloch Fort site in Galloway date to the Mesolithic period . A number of sites date to

3400-549: The Industrial Revolution would drive development as well. In 1878, the world's first hydroelectric power scheme was developed at Cragside in Northumberland , England, by William Armstrong . It was used to power a single arc lamp in his art gallery. The old Schoelkopf Power Station No. 1 , US, near Niagara Falls , began to produce electricity in 1881. The first Edison hydroelectric power station,

3485-806: The International Exhibition of Hydropower and Tourism , with over one million visitors 1925. By 1920, when 40% of the power produced in the United States was hydroelectric, the Federal Power Act was enacted into law. The Act created the Federal Power Commission to regulate hydroelectric power stations on federal land and water. As the power stations became larger, their associated dams developed additional purposes, including flood control , irrigation and navigation . Federal funding became necessary for large-scale development, and federally owned corporations, such as

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3570-694: The River Nith . Traditionally it has been described as stretching from "the braes of Glenapp to the Nith". The valleys of three rivers, the Urr Water , the Water of Ken and River Dee , and the Cree, all running north–south, provide much of the good arable land , although there is also some arable land on the coast. Generally however the landscape is rugged and much of the soil is shallow. The generally south slope and southern coast make for mild and wet climate, and there

3655-695: The Stuart dynasty in Britain and Ireland. James , the Stuart monarch of both Scotland and England, heavily policed the activities of the riding clans of the nearby Scottish Borders , leading to a large number of Borderers emigrating or being transported to Ireland or to the American colonies. The Plantation of Ulster began around this time. Attempts by the Stuarts to impose royal absolutism , as well as theological disputes over episcopacy, ultimately triggered

3740-633: The Tennessee Valley Authority (1933) and the Bonneville Power Administration (1937) were created. Additionally, the Bureau of Reclamation which had begun a series of western US irrigation projects in the early 20th century, was now constructing large hydroelectric projects such as the 1928 Hoover Dam . The United States Army Corps of Engineers was also involved in hydroelectric development, completing

3825-583: The Vulcan Street Plant , began operating September 30, 1882, in Appleton, Wisconsin , with an output of about 12.5 kilowatts. By 1886 there were 45 hydroelectric power stations in the United States and Canada; and by 1889 there were 200 in the United States alone. At the beginning of the 20th century, many small hydroelectric power stations were being constructed by commercial companies in mountains near metropolitan areas. Grenoble , France held

3910-506: The potential energy of dammed water driving a water turbine and generator . The power extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head . A large pipe (the " penstock ") delivers water from the reservoir to the turbine. This method produces electricity to supply high peak demands by moving water between reservoirs at different elevations. At times of low electrical demand,

3995-400: The water frame , and continuous production played a significant part in the development of the factory system, with modern employment practices. In the 1840s, hydraulic power networks were developed to generate and transmit hydro power to end users. By the late 19th century, the electrical generator was developed and could now be coupled with hydraulics. The growing demand arising from

4080-589: The "Galloway flail", a variant of the agriculturally-derived melee weapon . Galloway's agricultural economy was indirectly affected by the 17th-century Plantation of Ulster. Peasants in Galloway had, dating back to the Middle Ages, traditionally practiced a mixture of dairy-focused pastoral transhumance and intensive agriculture, with pockets of arable land being intensively cultivated by some peasants, while others migrated between upland and lowland pastures with their herds. Landowners such as Sir John Murray,

4165-582: The 17th-century Bishops' Wars in Scotland, which saw the appearance of the Covenanters as a social, political, and military force. The Covenanters began as participants in conventicles , which were unsanctioned secret religious gatherings that often took place outdoors, or in barns or granaries. The Covenanter movement was particularly popular in the southwest of Scotland. Covenanters had skirmishes with government troops in Galloway, some of which featured

4250-472: The Gaelic system of tanistry . In the ensuing Galloway revolt of 1234–1235 , an army of Galwegian rebels ambushed Alexander's royal army and nearly inflicted a defeat before relief forces arrived to support the king. The rebels retreated to Ireland, and Alexander left Walter Comyn, Lord of Badenoch to subdue Galloway; Comyn sacked its abbeys before fleeing when faced with the return of the rebels. The rebellion

4335-727: The Grim , Earl of Douglas . In 1369, he received the part of Galloway east of the River Cree , where he appointed a steward to administer the area, which became known as the Stewartry of Kirkcudbright . The following year, he acquired the part of Galloway west of the Cree, which continued to be administered by the king's sheriff, and so became known as the Shire of Wigtown . The two parts of Galloway thereafter were administered separately, becoming separate counties . The High Medieval period saw

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4420-463: The IEA released a main-case forecast of 141 GW generated by hydropower over 2022–2027, which is slightly lower than deployment achieved from 2017–2022. Because environmental permitting and construction times are long, they estimate hydropower potential will remain limited, with only an additional 40 GW deemed possible in the accelerated case. In 2021 the IEA said that major modernisation refurbishments are required. Most hydroelectric power comes from

4505-686: The Neolithic; these include the Drumtroddan standing stones , the Torhousekie stone circle , and the Cairnholy chambered cairn. There is also evidence of one of the earliest pit-fall traps in Europe which was discovered near Glenluce , Wigtownshire . The Iron Age is where prehistoric archaeological remains and recorded history overlap for Galloway. Galloway's Iron Age sites are similar to

4590-464: The ability to transport particles heavier than itself downstream. This has a negative effect on dams and subsequently their power stations, particularly those on rivers or within catchment areas with high siltation. Siltation can fill a reservoir and reduce its capacity to control floods along with causing additional horizontal pressure on the upstream portion of the dam. Eventually, some reservoirs can become full of sediment and useless or over-top during

4675-595: The balance between stream flow and power production. Micro hydro means hydroelectric power installations that typically produce up to 100 kW of power. These installations can provide power to an isolated home or small community, or are sometimes connected to electric power networks. There are many of these installations around the world, particularly in developing nations as they can provide an economical source of energy without purchase of fuel. Micro hydro systems complement photovoltaic solar energy systems because in many areas water flow, and thus available hydro power,

4760-518: The candidates for the Scottish Crown. Consequently, Scotland's Wars of Independence were disproportionately fought in Galloway. There were a large number of new Gaelic placenames being coined post 1320 (e.g. Balmaclellan ), because Galloway retained a substantial Gaelic speaking population for several centuries more. Following the Wars of Independence, Galloway became the fief of Archibald

4845-553: The century after Agricola's campaign, Ptolemy's work is a Roman perspective on Britain following the conquest, and not necessarily a reflection of pre-Roman social or ethnic groups. Ptolemy listed two peoples as inhabitants of the area around Galloway: the Novantae in the west (associated with Wigtownshire, Kirkcudbrightshire, and southern Ayrshire) and the Selgovae in the east (primarily associated with modern-day Dumfriesshire). It

4930-770: The context of both the vacuum left by Northumbria being filled by the resurgent Cumbric Britons and the influx of the Norse into the Irish Sea , including settlement in the Isle of Man and in the now English region of western Cumbria immediately south of Galloway. If it had not been for Fergus of Galloway who established himself in Galloway in the mid-twelfth century, the region would rapidly have been absorbed by Scotland. This did not happen because Fergus, his sons, grandsons and great-grandson Alan, Lord of Galloway , shifted their allegiance between Scottish and English kings. During

5015-404: The daily rise and fall of ocean water due to tides; such sources are highly predictable, and if conditions permit construction of reservoirs, can also be dispatchable to generate power during high demand periods. Less common types of hydro schemes use water's kinetic energy or undammed sources such as undershot water wheels . Tidal power is viable in a relatively small number of locations around

5100-505: The dams, sometimes destroying biologically rich and productive lowland and riverine valley forests, marshland and grasslands. Damming interrupts the flow of rivers and can harm local ecosystems, and building large dams and reservoirs often involves displacing people and wildlife. The loss of land is often exacerbated by habitat fragmentation of surrounding areas caused by the reservoir. Hydroelectric projects can be disruptive to surrounding aquatic ecosystems both upstream and downstream of

5185-462: The discovery of such sites eliciting antiquarian interest. For example, the Black Loch of Myrton site (which likely dates to around the 5th century BC) was discovered due to loch-draining activities in the area of the Maxwell family estate during the 19th century. The site received the attention of a local antiquarian, Sir Herbert Maxwell , who conducted a basic excavation. Initially thought to be

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5270-542: The earl of Annandale , received large land grants in Ulster which were only suitable for pasture. In order for their tenants in Ireland to pay rent, an export market had to be created, which was soon sanctioned by the Scottish Privy Council, for Irish cattle to be exported to England via Galloway. Some landowners used the cattle trade in the 17th century as a way to grow their landholdings, as the system of

5355-505: The east; the border between Kirkcudbrightshire and Wigtownshire is marked by the River Cree . The definition has, however, fluctuated greatly in size over history. A hardy breed of black, hornless cattle named Galloway cattle is native to the region, in addition to the more distinctive Belted Galloway or "Beltie". Galloway comprises the part of Scotland lying southwards from the Southern Upland watershed and westward from

5440-705: The effect of forest decay. Another disadvantage of hydroelectric dams is the need to relocate the people living where the reservoirs are planned. In 2000, the World Commission on Dams estimated that dams had physically displaced 40–80 million people worldwide. Because large conventional dammed-hydro facilities hold back large volumes of water, a failure due to poor construction, natural disasters or sabotage can be catastrophic to downriver settlements and infrastructure. During Typhoon Nina in 1975 Banqiao Dam in Southern China failed when more than

5525-399: The excess generation capacity is used to pump water into the higher reservoir, thus providing demand side response . When the demand becomes greater, water is released back into the lower reservoir through a turbine. In 2021 pumped-storage schemes provided almost 85% of the world's 190 GW of grid energy storage and improve the daily capacity factor of the generation system. Pumped storage

5610-534: The forest is inundated, substantial amounts of greenhouse gases may be emitted. Construction of a hydroelectric complex can have significant environmental impact, principally in loss of arable land and population displacement. They also disrupt the natural ecology of the river involved, affecting habitats and ecosystems, and siltation and erosion patterns. While dams can ameliorate the risks of flooding, dam failure can be catastrophic. In 2021, global installed hydropower electrical capacity reached almost 1,400 GW,

5695-453: The hands of the family of its last abbot, Edward Maxwell. Following the death of the pre-Reformation Bishop of Galloway in 1575, there were disputes over who would be bishop, and the seat was vacant for a considerable period of time in the late 16th century due to opposition to episcopacy in Scotland. The Anglo-Scottish Union of the Crowns took place in 1603, leading to the supremacy of

5780-506: The highest among all renewable energy technologies. Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can be used in coastal regions. China added 24 GW in 2022, accounting for nearly three-quarters of global hydropower capacity additions. Europe added 2 GW, the largest amount for the region since 1990. Meanwhile, globally, hydropower generation increased by 70 TWh (up 2%) in 2022 and remains

5865-519: The largest renewable energy source, surpassing all other technologies combined. Hydropower has been used since ancient times to grind flour and perform other tasks. In the late 18th century hydraulic power provided the energy source needed for the start of the Industrial Revolution . In the mid-1700s, French engineer Bernard Forest de Bélidor published Architecture Hydraulique , which described vertical- and horizontal-axis hydraulic machines, and in 1771 Richard Arkwright 's combination of water power ,

5950-750: The largest, producing 14 GW , but was surpassed in 2008 by the Three Gorges Dam in China at 22.5 GW . Hydroelectricity would eventually supply some countries, including Norway , Democratic Republic of the Congo , Paraguay and Brazil , with over 85% of their electricity. In 2021 the International Energy Agency (IEA) said that more efforts are needed to help limit climate change . Some countries have highly developed their hydropower potential and have very little room for growth: Switzerland produces 88% of its potential and Mexico 80%. In 2022,

6035-665: The last recorded speaker. In modern times, Stranraer was a major ferry port, but the company have now moved to Cairnryan . Galloway has been the setting of a number of novels, including Walter Scott 's Guy Mannering . Other novels include the historical fiction trilogy by Liz Curtis Higgs, Thorn in My Heart , Fair is the Rose , and Whence Came a Prince . Richard Hannay flees London to lie low in Galloway in John Buchan 's novel The Thirty-nine Steps . Five Red Herrings ,

6120-416: The legendary King Arthur , and may also have been the caput of the sub-Roman Brythonic kingdom of Rheged . Rerigonium 's exact position is uncertain except that it was 'on Loch Ryan ', close to modern day Stranraer ; it is possible that it is the modern settlement of Dunragit ( Dun Rheged ). According to tradition, before the end of Roman rule in Britain , St. Ninian established

6205-633: The plant site. Generation of hydroelectric power changes the downstream river environment. Water exiting a turbine usually contains very little suspended sediment, which can lead to scouring of river beds and loss of riverbanks. The turbines also will kill large portions of the fauna passing through, for instance 70% of the eel passing a turbine will perish immediately. Since turbine gates are often opened intermittently, rapid or even daily fluctuations in river flow are observed. Drought and seasonal changes in rainfall can severely limit hydropower. Water may also be lost by evaporation. When water flows it has

6290-450: The rainfall regime, could reduce total energy production by 7% annually by the end of the century. Lower positive impacts are found in the tropical regions. In lowland rainforest areas, where inundation of a part of the forest is necessary, it has been noted that the reservoirs of power plants produce substantial amounts of methane . This is due to plant material in flooded areas decaying in an anaerobic environment and forming methane,

6375-471: The region including The Raiders and Silver Sand . Galloway is also the setting of several memoirs, including Devorgilla Days written by Wigtownshire author Kathleen Hart, an account of life in Wigtown , Scotland's national book town. 55°03′N 4°08′W  /  55.050°N 4.133°W  / 55.050; -4.133 Hydroelectric Hydroelectricity , or hydroelectric power ,

6460-407: The relatively low occurrence of rotary querns at sites in the area. Roughly contemporary with the Rispain Camp site, a cluster of roundhouses at Dunragit (dating to the early centuries AD) was revealed to contain examples of native (i.e. non-Roman) pottery. Certain households in Galloway seem to have taken social prominence later in the Iron Age. Lead items appear; isotope analysis of goods at

6545-479: The rest of Scotland. Its distinctive type sites consist of crannogs , promontory forts, and duns . Galloway has a preponderance of crannog-type sites compared to certain other regions of Scotland. This is due largely to the region's geography favouring lochs (or now-former lochs), as well as a bias toward higher survival rates of undisturbed sites available for archaeological investigation due to loch-draining taking place later in Galloway than in other regions, with

6630-493: The sea." While many surviving sites represent sporadically-occupied locations or individual households, there are also examples of multiple-household settlements. One of these is the Rispain Camp site near Whithorn, which contained a form of bread wheat unique amongst Iron Age sites in Galloway. This is a possible indication that Rispain Camp had different agricultural practices than elsewhere in Galloway, especially given

6715-548: The trackless wastes") having been corrupted into annonave prima transgressus , which is grammatically incorrect in Latin. The interpretation that this passage refers to Galloway is based on contextual information, as the work later refers to "the part of Britain that faces Ireland", which is seen as referring to southwestern Scotland. In the 2nd century, the Alexandrian geographer Ptolemy produced his Geographia , which

6800-524: The world are hydroelectric power stations, with some hydroelectric facilities capable of generating more than double the installed capacities of the current largest nuclear power stations . Although no official definition exists for the capacity range of large hydroelectric power stations, facilities from over a few hundred megawatts are generally considered large hydroelectric facilities. Currently, only seven facilities over 10 GW ( 10,000 MW ) are in operation worldwide, see table below. Small hydro

6885-539: The world. The classification of hydropower plants starts with two top-level categories: The classification of a plant as an SHP or LHP is primarily based on its nameplate capacity , the threshold varies by the country, but in any case a plant with the capacity of 50 MW or more is considered an LHP. As an example, for China, SHP power is below 25 MW, for India - below 15 MW, most of Europe - below 10 MW. The SHP and LHP categories are further subdivided into many subcategories that are not mutually exclusive. For example,

6970-586: Was allowed to provide irrigation and power to citizens (in addition to aluminium power) after the war. In Suriname , the Brokopondo Reservoir was constructed to provide electricity for the Alcoa aluminium industry. New Zealand 's Manapouri Power Station was constructed to supply electricity to the aluminium smelter at Tiwai Point . Since hydroelectric dams do not use fuel, power generation does not produce carbon dioxide . While carbon dioxide

7055-555: Was chairman of Falkirk F.C. during the 2000s. During his tenure, Falkirk were promoted to the Scottish Premier League and developed the Falkirk Stadium . He stepped down in 2009, making the announcement after Falkirk played in the 2009 Scottish Cup Final . Christie died at Strathcarron Hospice, Denny, Falkirk, aged 74, on 28 October 2011, after a short illness. This Scottish biographical article

7140-503: Was eventually ended with the return of royal forces. The result was a partition of Galloway, serving to fragment it administratively, though some ecclesiastical (the bishopric) and judicial (the office of Justiciar of Galloway ) offices survived further into the High Medieval period and beyond. Alan's eldest daughter, Derbhorgail (Latinized as Dervorguilla), married John de Balliol , and their son (also John ) became one of

7225-474: Was written c.  AD 150 . This work included Britain. No surviving copies of the Geographia exist which are older than the 13th century, creating the possibility that details may have been lost or distorted. Ptolemy credited much of his work to a now-lost atlas by Marinus of Tyre , a previous geographer whose work is thought to have been created around AD 114. Though it would have been written within

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