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74-513: A series of hydro-electric projects have been constructed on the river. Its waters are in demand to irrigate crops. The river is called Ildaruni in Urartian inscriptions. The name Hrazdan derives from a Middle Iranian form of Avestan Frazdānu , which in Zoroastrian mythology is the body of water by which Vishtaspa converted to Zoroastrianism. Frazdānu is composed of

148-745: 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

222-463: 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

296-475: A 16 km stretch of the river, from 2 km upstream of the Yerevan wastewater outfalls to 14 km below, is insufficiently aerated to provide a healthy environment for aquatic life. Hydro-electric Hydroelectricity , or hydroelectric power , is electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity , almost 4,210 TWh in 2023, which

370-531: A 70 kilometres (43 mi) stretch of the river with a total installed capacity of 560 MW with mean annual energy generation of around 500 million kilowatt hours; it is the largest hydro-power generating scheme in Armenia. This scheme was implemented between 1930 and 1962. These are small- and medium-size projects built as run-of-the river power plants. The seven power stations are: Sevan HEP with installed capacity of 34.2 MW with two units completed in 1949;

444-534: A US$ 25 million loan from the Asian Development Bank . The river water is polluted by effluent flows from agricultural, commercial, industrial, and residential development, but particularly by the untreated wastewater from Yerevan. This affects the water quality in the river with dissolved oxygen (DO) levels (less than 5% of the saturated dissolved oxygen level) remaining much lower than the permissible limits. A study carried out in 2008 indicates that

518-421: 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

592-494: 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 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

666-809: 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

740-451: 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

814-592: 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

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888-548: 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

962-540: 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

1036-448: 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

1110-455: 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

1184-414: 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

1258-605: A total catchment area of 2,566 square kilometres (991 sq mi). Precipitation volume is 1572 million cubic metre from an annual rainfall of 257 millimetres (10.1 in) with a maximum of 43 millimetres (1.7 in) in May and a minimum of 8 millimetres (0.31 in) during August. The average temperature recorded in the basin varies from −3 °C (27 °F) in January to 26 °C (79 °F) in July with diurnal variation with

1332-581: 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

1406-522: A year's worth of rain fell within 24 hours (see 1975 Banqiao Dam failure ). The resulting flood resulted in the deaths of 26,000 people, and another 145,000 from epidemics. Millions were left homeless. The creation of a dam in a geologically inappropriate location may cause disasters such as 1963 disaster at Vajont Dam in Italy, where almost 2,000 people died. Sevan%E2%80%93Hrazdan Cascade Sevan–Hrazdan Cascade ( Armenian : Սևան-Հրազդան Կասկադ )

1480-452: 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

1554-471: Is 375 GWh, but the factual generation for the last years has been about 40 GWh. The Argel Hydroelectric Power Plant, is located between the Hrazdan and Arzni stations. It is the largest power plant of the cascade. It has four turbines, supplied by LMZ , with total installed nominal capacity of 224 MW and available capacity about 168 MW. Its nominal annual generation is 870 GWh, but

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1628-741: Is a complex of hydroelectric power plants on the Hrazdan River and its tributaries between the Lake Sevan and Yerevan in Armenia . They use irrigation water flow from the Lake Sevan and streams waters of Hrazdan River. The cascade is owned by the International Energy Corporation (IEC), a subsidiary of Tashir Group owned by Samvel Karapetyan . The first small-scale Yerevan Hydroelectric Power Plant (HPP)

1702-635: 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

1776-470: 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

1850-401: Is important for providing the peak-load capacity as also supplying Yerevan with irrigation and industrial water. The plant was rehabilitated in 1993–1995, a project financed by USAID , Energy pour l’Armenie and Aznavour pour l’Armenie. In 1995, the unit 5 and in 2000, the unit 6 were shut for the renovation, financed by the loan from KfW . These units were reopened in 2003. The renovation

1924-445: 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

1998-590: Is located between of the Argel and Kanaker stations. It has three turbines with total installed capacity of 70.6 MW. Its nominal annual generation is 300 GWh, but the factual generation for the last years has been about 80 GWh. The Kanaker Hydroelectric Power Plant is located next to the Rusal Armenal aluminum smelter in the Kanaker-Zeytun District of Yerevan, in between of

2072-471: 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 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

2146-462: 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

2220-452: 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

2294-410: 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

Hrazdan (river) - Misplaced Pages Continue

2368-679: 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

2442-806: 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

2516-633: 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

2590-583: 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

2664-506: 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,

2738-458: The "Sevan-Hrazdan Management Area", which is one of the five sub-basins of the 14 sub-basins of Kura and Araks basins of Armenia. The river originates from the lake at an elevation of 1,900 metres (6,200 ft). The river which flows from the lake in a southern direction passes through a deep gorge as it enters on the western side of the Yerevan city, and then debauchees into the Aras River on

2812-535: The 19th century, and from early 20th century hydro-power development has also been implemented. The lake waters were planned to be used through the river for irrigating 100,000 hectares (250,000 acres) in the Ararat Valley out of which an irrigation of 80,000 hectares (200,000 acres) was created. The hydro-power development was planned on the river as the Sevan–Hrazdan Cascade involving seven schemes in

2886-569: The Arzni HPP and the Yerevan-1 HPP. It has a total installed capacity of 100 MW which consists of four turbines with capacity of 12.5 MW each and two turbines with capacity of 25 MW each, all supplied by LMZ. The nominal installed capacity is !00 MW and the factual capacity is 87.5 MW. Its nominal annual generation is 425 GWh, but the factual generation for the last years has been about 110 GWh. The plant

2960-475: The HPPs through open diversion canals and tunnels . Most of these canals were built in 1960s and are now in poor conditions and require rehabilitation. Source: IEC, Asbarez The Sevan Hydroelectric Power Plant, is the upper power station of the cascade. It is an underground power station locating 100 metres (330 ft) below the surface. It has two turbines with a total nominal capacity of 34.2 MW and

3034-698: The Hrazdan HEP of 81.6 MW with two units commissioned in 1959; the Argel HEP with installed capacity of 224 MW completed in 1953; the Arzni HEP with capacity of 70.6 MW with installation of 3 units commissioned in 1956; the Kanaker HEP with installed capacity of 100 MW with 6 units completed in 1936; the Yerevan-1 HEP commissioned in 1962 with installation of 44 MW with 2 units; and

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3108-463: 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

3182-523: The Sevan–Hrazdan Cascade is highly dependent on the amount of water drainage from the Lake Sevan and it is suitable for the daily peak generation. Five HPPs operate all year long and two HPPs work only during the irrigation season when additional water is available in the system. Therefore, the power generation during the winter is limited. The water is transported from the Lake Seven to

3256-459: The Yerevan-3 with capacity of 5 MW with one unit commissioned in 1960. However, priority of release of water from the lake is for irrigation and accordingly the power stations are operated. The civil works involved construction of diversion works, open canals or tunnels and power house which over the years were in need of substantial rehabilitation as they were all built around the middle of

3330-464: 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

3404-595: 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,

3478-468: The cascade was given to Inter RAO UES in return for US$ 25 million debt by Armenia. For operation of the cascade, the IEC was incorporated. In 2011, Rushydro bought the IEC from Inter RAO. In 2019 newspaper reported, that Rushydro is going to sell at $ 2.7 million cascade to Tashir group , owned by Samvel Karapetyan . By then the same Tashir Group already owned electricity distributions networks in

3552-466: The center part of Yerevan. The Yerevan Hydroelectric Power Plant-3 is located in Yerevan. It has one turbined with installed capacity of 5 MW. Its diversion channel and penstock are part of the Artashat irrigation channel. There is a rehabilitation project going on the Sevan–Hrazdan Cascade that is predicted to be completed in 2017. The main goal of the rehabilitation project is to re-establish

3626-590: The country. Buyer had to settle all debts running at $ 55.13 million by the end of September 2019. The deal was signed in December 2019 and finalized in early 2020. Sevan–Hrazdan Cascade is stretched over about 70 kilometres (43 mi) and consists of seven hydroelectric power plants (HPP), with total nominal capacity of 565 MW. The HPPs are Sevan, Hrazdan, Argel, Arzni, Kanaker, Yerevan-1 and Yerevan-3—all run-of-the-river type. The cascade produces about 10% of Armenia's electricity. Electricity generation at

3700-404: 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

3774-505: 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

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3848-705: 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

3922-525: The elements fraz 'elevated, high' and dānu 'river'. Dānu derives from the same Iranian root as a number of hydronyms in Europe, such as Don , Dnieper , Danube and Dniester . The change of word-initial fr- to hr- can be seen in a number of Iranian borrowings into Armenian. The Hrazdan is mentioned in Movses Khorenatsi's history. In the history attributed to Sebeos ,

3996-399: 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

4070-622: The factual capacity of about 24 MW. Its nominal annual generation is 130 GWh, but the factual generation for the last years has been about 15 GWh. The water intake of the Sevan HPS was renovated in 2010. The Hrazdan Hydroelectric Power Plant, known as Atarbekyan during the Soviet years, is located between the Sevan and Argel stations. It has two turbines with a total installed capacity of 81.6 MW. Its nominal annual generation

4144-682: The factual generation for the last years has been about 200 GWh. The plant is important for ensuring the frequency of the Armenian power system, ensuring the emergency supply to the Metsamor Nuclear Power Plant , and supplying peak-load capacity. In May 1995, landslides caused by heavy rains destroyed one of the plant spillways and blocked the Hrazdan River channel. It was restored and reopened in 2000 and 2006 correspondingly. The Arzni Hydroelectric Power Plant

4218-518: The form Hurazdan is used, while some later Armenian historians use the form Hurastan . Its name in Turkic languages is Zangu , Zanga , Zangi , or Zengy . It was called Zanga in Tsarist Russian nomenclature. Lake Sevan (with 30 rivers contributing to its storage), the largest located in the central part of the country and the Hrazdan River which originates from it, together form

4292-417: The initial capacity of the cascade. The planned works for the rehabilitation project include a complete reconstruction of Yerevan-1 HPP. Sevan HPP, Hrazdan HPP, Argel HPP, Arzni HPP, and Kanaker HPP will have a new electrical equipment, such as new accumulators and generators. Also the hydro units of Argel HPP, Hrazdan HPP and Kanaker HPP will be replaced. As there is a plan to dredge Yerevan-1 dam right on

4366-501: The largest amount for the region since 1990. Meanwhile, globally, hydropower generation increased by 70 TWh (up 2%) in 2022 and remains 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

4440-750: 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,

4514-616: The late 19th century, the electrical generator was developed and could now be coupled with hydraulics. The growing demand arising from 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,

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4588-690: The lowest night temperature of −15 °C (5 °F) in January and highest day temperature of 44 °C (111 °F) in July. The total flow in the river is 733 million cubic meter. The regulated outflow into the river, which forms the Ararat Valley, is utilized for irrigation and hydro-power benefits. The fauna reported from the river includes 33 species of chironomids and 23 species of blackflies . The chironomids belong to five subfamilies of Tanypodinae , Diamesinae , Prodiamesinae , Orthocladiinae , and Chironominae . 25 species of invertebrates comprising two species of rotifers , 13 species of cladocerans and 10 species of copepods have been recorded in

4662-488: 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 , 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

4736-651: 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, 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,

4810-633: 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

4884-450: 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,

4958-489: The river. While the fish species contained in the lake consist of the Sevan trout ( Salmo ischchan ) or “Prince Fish,” siga, crucian, carp, crayfish, bojak ( Salmo ischchan danilewskii ) and winter bakhtak ( Salmo ischchan ischchan ) and summer bakhtak ( Salmo ischchan aestivalis ), the river is reported to have species of crayfish as well as karas and crayfish in abundance. The lake waters have been used for irrigation since

5032-460: The southern side of the city. The geological formations along the river course are made up of lava flows (existing as basalts) generated from three volcanoes in the Gegham range. The lava surfaces represent environments that existed in the form of "lakes, river channels and floodplains". The chronology of landscape of the upper most layer of basalts indicates an age of 200,000 years. The river drains

5106-518: The twentieth century. In 2003, the International Energy Corporation", a Closed Joint Stock Company, acquired the projects from the Public Services Regulatory Commission of the country under a license No. 0108 for generation of electrical energy. Right from the time of acquisition they started rehabilitating the projects to maximize power generation. The works were completed during 2004. The works were carried out under

5180-524: 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

5254-539: 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,

5328-586: 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

5402-785: Was built in 1923. In 1932, it was replaced by Yerevan-2 HPS. The construction of the current cascade started in 1936, when the Kanaker HPS was opened. That time it was planned to build the whole cascade by 1947. In 1940, construction of the Sevan HPS started but due to World War II , construction was suspended and the HPS became operational only in 1949. The largest HPS, Argel HPS, was opened in 1953, followed by Arzni HPS in 1953, Yerevan-3 HPS in 1955, Hrazdan HPS in 1959 and Yerevan-1 HPS in 1962. The original plan included also construction of three more HPSs—Upper Argavand HPS, Lower Argavand HPSand Noragavit HPS—but these plants were never built. In 2003

5476-495: Was carried out by Alstom Power Generation . The Yerevan Hydroelectric Power Plant-1 is located between the Kanaker and Yerevan-3 stations, at the central Kentron District of Yerevan. It has two turbines with the total installed nominal capacity of 44 MW and available capacity of 22 MW. Its nominal annual generation is 210 GWh, but the factual generation for the last years has been about 50 GWh. It supplies

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