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Mandraka Power Station
Mandraka Dam is a gravity dam on the Mandraka River near Mandraka in the Analamanga Region of Madagascar. The dam was constructed by a French firm by 1956 and creates Lake Mandraka. Mandraka Power Station The dam supplies water to a hydroelectric power station to the east, down in the valley. The change in elevation between the dam and power station affords a hydraulic head on . The dam and power station are operated and owned by Jirama and the four Pelton turbine-generators were commissioned between 1958 and 1972. See also *Mantasoa Dam Mantasoa Dam is a buttress dam on the Varahina-North River, a tributary of the Ikopa River, near Mantasoa in the Analamanga Region of Madagascar. The dam was constructed by French contractors between 1937 and 1938. It creates Lake Mantasoa whic ... – regulates water flow to Mandraka Dam References {{reflist Dams in Madagascar Analamanga Gravity dams Dams completed in 1956 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analamanga Region
Analamanga is a region in central Madagascar, containing the capital Antananarivo and its surrounding metropolitan area. The region has an area of , and had a population of 3,618,128 in 2018. Administrative divisions Analamanga Region is divided into eight districts, which are sub-divided into 137 communes. * Ambohidratrimo District - 24 communes * Andramasina District - 14 communes * Anjozorobe District - 18 communes * Ankazobe District - 15 communes * Antananarivo-Atsimondrano District - 26 communes * Antananarivo-Avaradrano District - 16 communes * Antananarivo-Renivohitra District - 1 commune; the city of Antananarivo * Manjakandriana District - 23 communes Geography The region extends mainly towards the north of the capital. It is bordered by Betsiboka to the north, Bongolava and Itasy to the west, Alaotra Mangoro to the east, and Vakinankaratra to the south. Rivers The main rivers are the Betsiboka River and the Ikopa River. Major lakes Lake Mantasoa (1375 ha) and T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jirama
Jirama ( ''Jiro sy rano malagasy'') is a state-owned electric utility and water services company in Madagascar. History The Jirama was established on 17 October 1975 when the Société Malagasy des Eaux et Electricité and the Société des Energies de Madagascar merged. Up until 1999, it was the only state-owned electricity company of the country. After 1999, the Jirama maintained its monopoly on transportation and distribution networks. In 2007, when Antananrivo's Mayor Andry Rajoelina took office, the city's treasury had a debt of 8.2 billion Malagasy Ariary (approximately 4.6 million U.S. dollars). On 4 January 2008, because of unpaid debts to the Jirama, the city of Antananarivo was hit by a general water cutoff and brownouts of the city's street lights. After an audit, it was found that the Jirama owed about the same amount of money to the city, and the sanction on the city's population was relieved. In 2008, thanks to the launch of a new thermal power plant in Mandrosez ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelton-type
The Pelton wheel or Pelton Turbine is an impulse-type water turbine invented by American inventor Lester Allan Pelton in the 1870s. The Pelton wheel extracts energy from the impulse of moving water, as opposed to water's dead weight like the traditional overshot water wheel. Many earlier variations of impulse turbines existed, but they were less efficient than Pelton's design. Water leaving those wheels typically still had high speed, carrying away much of the dynamic energy brought to the wheels. Pelton's paddle geometry was designed so that when the rim ran at half the speed of the water jet, the water left the wheel with very little speed; thus his design extracted almost all of the water's impulse energywhich made for a very efficient turbine. History file:Pelton wheel (patent).png, Figure from Lester Allan Pelton's original October 1880 patent Lester Allan Pelton was born in Vermillion, Ohio in 1829. In 1850, he traveled overland to take part in the California Gold Rush. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Dam
A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation to oppose the horizontal pressure of water pushing against it. Gravity dams are designed so that each section of the dam is stable and independent of any other dam section. Characteristics Gravity dams generally require stiff rock foundations of high bearing strength (slightly weathered to fresh), although in rare cases, they have been built on soil foundations. The bearing strength of the foundation limits the allowable position of the resultant force, influencing the overall stability. Also, the stiff nature of the gravity dam structure is unforgiving to differential foundation settlement, which can induce cracking of the dam structure. Gravity dams provide some advantages over embankment dams, the main advantage being that they can tolerate minor over-topping flows without damage, as the concre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa across the Mozambique Channel. At Madagascar is the world's List of island countries, second-largest island country, after Indonesia. The nation is home to around 30 million inhabitants and consists of the island of Geography of Madagascar, Madagascar (the List of islands by area, fourth-largest island in the world), along with numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian subcontinent around 90 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of wildlife of Madagascar, its wildlife is endemic. Human settlement of Madagascar occurred during or befo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Mandraka
Lake Mantasoa is a large lake created by the Mandraka Dam on the Mandraka River in the Analamanga region Analamanga is a region in central Madagascar, containing the capital Antananarivo and its surrounding metropolitan area. The region has an area of , and had a population of 3,618,128 in 2018. Administrative divisions Analamanga Region is divided in ... of Madagascar. It has an extension of 2005 ha. References Mandraka Analamanga {{Madagascar-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroelectric
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, 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 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. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Head
Hydraulic head or piezometric head is a specific measurement of liquid pressure above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22. It is usually measured as a liquid surface elevation, expressed in units of length, at the entrance (or bottom) of a piezometer. In an aquifer, it can be calculated from the depth to water in a piezometric well (a specialized water well), and given information of the piezometer's elevation and screen depth. Hydraulic head can similarly be measured in a column of water using a standpipe piezometer by measuring the height of the water surface in the tube relative to a common datum. The hydraulic head can be used to determine a ''hydraulic gradient'' between two or more points. "Head" in fluid dynamics In fluid dynamics, ''head'' is a concept that relates the energy in an incompressible fluid to the height of an equivalent static column of that fluid. From Bernoulli's principle, the total energy at a given point in a fluid i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pelton Turbine
The Pelton wheel or Pelton Turbine is an impulse-type water turbine invented by American inventor Lester Allan Pelton in the 1870s. The Pelton wheel extracts energy from the impulse of moving water, as opposed to water's dead weight like the traditional overshot water wheel. Many earlier variations of impulse turbines existed, but they were less efficient than Pelton's design. Water leaving those wheels typically still had high speed, carrying away much of the dynamic energy brought to the wheels. Pelton's paddle geometry was designed so that when the rim ran at half the speed of the water jet, the water left the wheel with very little speed; thus his design extracted almost all of the water's impulse energywhich made for a very efficient turbine. History file:Pelton wheel (patent).png, Figure from Lester Allan Pelton's original October 1880 patent Lester Allan Pelton was born in Vermillion, Ohio in 1829. In 1850, he traveled overland to take part in the California Gold Rush. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mantasoa Dam
Mantasoa Dam is a buttress dam on the Varahina-North River, a tributary of the Ikopa River, near Mantasoa in the Analamanga Region of Madagascar. The dam was constructed by French contractors between 1937 and 1938. It creates Lake Mantasoa which has a surface area of . The dam itself is made of of concrete and has a reinforced buttress design. Water released from the dam supplies a regulated flow to hydroelectric power station at the Antelomita Dams downstream. A saddle dam on the north side of the Mantosoa reservoir regulates water flow into the Mandraka River for the Mandraka Dam Mandraka Dam is a gravity dam on the Mandraka River near Mandraka in the Analamanga Region of Madagascar. The dam was constructed by a French firm by 1956 and creates Lake Mandraka. Mandraka Power Station The dam supplies water to a hydroelect ... downstream. See also * Tsiazompaniry Dam – on the Varahina South River References {{reflist Dams in Madagascar Analamanga Buttress dams Dam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
