Paulo Afonso Hydroelectric Complex
Encyclopedia
The Paulo Afonso Hydroelectric Complex (Complexo Hidrelétrico de Paulo Afonso), also known as the Paulo Afonso Complex, is a system of three dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...

s and five hydroelectric power plants on the São Francisco River
São Francisco River
The São Francisco is a river in Brazil. With a length of , it is the longest river that runs entirely in Brazilian territory, and the fourth longest in South America and overall in Brazil...

 near the city of Paulo Afonso
Paulo Afonso
Paulo Afonso is a city in Bahia, Brazil. It is located at around . It was founded in 1958.The city is the seat of the Roman Catholic Diocese of Paulo Afonso.The city is served by Paulo Afonso Airport....

 in Bahia
Bahia
Bahia is one of the 26 states of Brazil, and is located in the northeastern part of the country on the Atlantic coast. It is the fourth most populous Brazilian state after São Paulo, Minas Gerais and Rio de Janeiro, and the fifth-largest in size...

, Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

. The complex exploits an 80 m (262.5 ft) natural gap on the river, known as the Paulo Afonso Falls
Paulo Afonso Falls
Paulo Afonso Falls is a series of waterfalls on the São Francisco River in the northeastern section of Brazil adjacent to the city of Paulo Afonso. It stands high. Upstream of the falls, a hydroelectric dam, the Hidrelétrica de Angiquinho blocks the flow of the river...

. Constructed in succession between 1948 and 1979, the dams support the Paulo Afonso I, II, III, IV and Apollonius Sales (Moxotó) power plants which contain a total of 23 generators with an installed capacity of 4,279.6 MW.

PA I was the first large power plant constructed in Brazil and the complex constitutes the densest area of dams in Brazil. The complex provides electricity to areas in northeastern Brazil and is the main tourist attraction in the region.

Background and history

On January 23, 1913, the 1.1 MW Angiquinho Hydroelectric Plant, built by industrialist Delmiro Gouveia, was the first use of the Paulo Afonso Falls
Paulo Afonso Falls
Paulo Afonso Falls is a series of waterfalls on the São Francisco River in the northeastern section of Brazil adjacent to the city of Paulo Afonso. It stands high. Upstream of the falls, a hydroelectric dam, the Hidrelétrica de Angiquinho blocks the flow of the river...

 for power production and the first hydroelectric power plant in northeastern Brazil. Construction of the power plant was intended to spur economic growth in the area and soon after another hydroelectric plant was constructed upstream near Petrolândia
Petrolândia
Petrolândia is a town in the state of Pernambuco, Brazil. It is in the São Francisco Region. Petrolândia has a total area of 1056.6 square kilometers and had an estimated population of 32.568 inhabitants in 2009 according with IBGE...

. By the 1940's Brazil's Ministry of Agriculture recognized the importance of harnessing the São Francisco River
São Francisco River
The São Francisco is a river in Brazil. With a length of , it is the longest river that runs entirely in Brazilian territory, and the fourth longest in South America and overall in Brazil...

 for economic development in the semi-arid region. They began to plan the river's development and the Companhia Hidro-Elétrica do São Francisco (CHESF
CHESF
CHESF generates and transmits electric power from hydroelectric plants to all of the cities in northeast of Brazil....

) was formed in 1945. On May 23, 1944, construction on Paulo Afonso I had been authorized with two generators. Construction began in 1948; workers and engineers experienced difficulty diverting the river, transporting the turbines to the site while in midst of dangerous work conditions. Tunnels and a cavern had to be excavated for Brazil's first underground power plant
Underground power station
An underground power station is a type of hydroelectric power station constructed by excavating the major components from rock, rather than the more common surface-based construction methods....

. Due to the depth and strength of the river near the falls, it was not diverted until 1954. On January 15, 1955, Brazilian President João Café Filho
João Café Filho
João Fernandes Campos Café Filho was a Brazilian politician. Born in Natal, Rio Grande do Norte state, Café Filho was a journalist and federal deputy, elected vice-president in 1950, under Getúlio Vargas. Following the Vargas suicide in 1954, Café Filho assumed the presidency...

 inaugurated PA I. Previously, in 1953, CHESF negotiated with the government for a third generating unit at PA I and the excavation of another underground power plant for the future PA II adjacent to PA I on the falls. The third generator at PA I was commissioned on September 18, 1955 and construction of PA II began that year as well.

By 1961, PA II was complete and on October 24 that year, its first generator was commissioned. PA II's five other generators became operational between 1962 and December 18, 1967. Construction on PA III started soon after in 1967 and was complete in 1971 with its first generator commissioned on October 21 that year. Another generator was commissioned in 1972 and the final two in 1974, the last of which on August 5th. In 1971, construction had moved to the Apollonius Sales (Moxotó) Dam and power plant 4 km (2.5 mi) upstream from the falls. In 1977, construction was completed and its four generators went online in April of that year. In 1972, construction began on the final dam and power plant, PA IV, 2 km (1.2 mi) southwest of the falls. Construction was complete in 1979 and its first generator commissioned on December 1. Two more generators were commissioned in 1980, two in 1981 and the final on May 28, 1983.

Construction of the dams caused a loss of 1600 ha (3,953.7 acre) of land along with displacing 52,000 people.

Apollonius Sales (Moxotó)

The Appollonius Sales Dam and power plant were originally known as Moxotó but were renamed after Appollonius Sales, the founder of CHESF. The dam is a 30 m (98.4 ft) high, 2825 m (9,268.4 ft) long rock and earth-fill embankment dam
Embankment dam
An embankment dam is a massive artificial water barrier. It is typically created by the emplacement and compaction of a complex semi-plastic mound of various compositions of soil, sand, clay and/or rock. It has a semi-permanent waterproof natural covering for its surface, and a dense, waterproof...

. The dam withholds a 1200000000 cubic metre capacity reservoir with a surface area of 100 square kilometre and catchment area of 630000 square kilometre. The dam and its reservoir are primarily intended to regulate water flow to PA I, II and III 4 km (2.5 mi) downstream. On the dam's west side, it supports a 20 floodgate
Floodgate
Floodgates are adjustable gates used to control water flow in flood barriers, reservoir, river, stream, or levee systems. They may be designed to set spillway crest heights in dams, to adjust flow rates in sluices and canals, or they may be designed to stop water flow entirely as part of a levee or...

 spillway
Spillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...

 with a 28000 m3/s capacity. The power plant is located on the east side of the dam near the reservoir's shore and contains four generators
Electrical generator
In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge to flow through an external electrical circuit. It is analogous to a water pump, which causes water to flow...

, each with Kaplan turbine
Kaplan turbine
The Kaplan turbine is a propeller-type water turbine which has adjustable blades. It was developed in 1913 by the Austrian professor Viktor Kaplan, who combined automatically adjusted propeller blades with automatically adjusted wicket gates to achieve efficiency over a wide range of flow and...

s. Each generator has an nameplate capacity
Nameplate capacity
Nameplate capacity, also known as the rated capacity, nominal capacity, installed capacity or maximum effect, refers to the intended technical full–load sustained output of a facility such as a power plant, a chemical plant, fuel plant, metal refinery, mine, and many others.For dispatchable power,...

 of 100 MW for a total installed capacity of 400 MW.

Paulo Afonso I, II, III

Situated directly on top of the Paulo Afonso Falls
Paulo Afonso Falls
Paulo Afonso Falls is a series of waterfalls on the São Francisco River in the northeastern section of Brazil adjacent to the city of Paulo Afonso. It stands high. Upstream of the falls, a hydroelectric dam, the Hidrelétrica de Angiquinho blocks the flow of the river...

, the Delmiro Gouveia Dam supports Paulo Afonso I, II and III. The dam is 20 m (65.6 ft) high, 4707 m (15,442.9 ft) long and is a concrete gravity type. The reservoir formed by the dam has a 26000000 cubic metre capacity and surface area of 4.8 square kilometre. The dam has one uncontrolled spillway and a controlled spillway on its outer linings while also supporting four controlled spillways on the front of the falls. These four surface spillways when open, discharge water below and essentially recreate the falls.

All three power plants are about 82 m (269 ft) underground and adjacent to one another. PA I lies in the center and is housed in a 60 m (196.9 ft) long, 31 m (101.7 ft) high and 15 m (49.2 ft) wide cavern. It contains three 60 MW generators with Francis turbine
Francis turbine
The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. It is an inward-flow reaction turbine that combines radial and axial flow concepts....

s, for an installed capacity of 180 MW. The generators are Vertical Sync-type and were manufactured by Westinghouse
Westinghouse Electric (1886)
Westinghouse Electric was an American manufacturing company. It was founded in 1886 as Westinghouse Electric Company and later renamed Westinghouse Electric Corporation by George Westinghouse. The company purchased CBS in 1995 and became CBS Corporation in 1997...

. The turbines were manufactured by Dominion Engineering Works
Andritz AG
Andritz AG is an Austrian plant engineering group headquartered in Graz. The group gets its name from the district Andritz in which it is located.Andritz employs more than 16,100 employees at 35 production and service facilities and 120 subsidiaries...

. PA II is a 104 m (341.2 ft) long, 36 m (118.1 ft) high and 18 m (59.1 ft) wide power house. It contains six Vertical Sync-type generators with Francis turbines. Two of the generators are 70 MW, one is 75 MW and the remaining three are 76 MW, for a total installing capacity of 443 MW. The generators were manufactured by S. Morgan Smith and Hitachi
Hitachi
Hitachi is a multinational corporation specializing in high-technology.Hitachi may also refer to:*Hitachi, Ibaraki, Japan*Hitachi province, former province of Japan*Prince Hitachi and Princess Hitachi, members of the Japanese imperial family...

 while the turbines by Voith
Voith
The Voith GmbH, which is headquartered in Germany, is a family-run corporation in the mechanical engineering sector with worldwide operations....

. PA III's power house is 127 m (416.7 ft) long, 46 m (150.9 ft) high and 18 m (59.1 ft) wide. It contains four 198.55 MW Vertical Sync-type generators manufactured by Siemens
Siemens
Siemens may refer toSiemens, a German family name carried by generations of telecommunications industrialists, including:* Werner von Siemens , inventor, founder of Siemens AG...

for an installed capacity of 794.2 MW. Each generator utilizes a Francis turbine manufactured by Voith.

Paulo Afonso IV

The Paulo Afonso Dam located 2 km (1.2 mi) southwest of the falls is 35 m (114.8 ft) high and 7430 m (24,376.6 ft) long. The dam is an earth and rock-fill type but contains 1053 m (3,454.7 ft) in length of concrete structures which include the power plant's intake and the spillway. The spillway is composed of eight floodgates and has a maximum discharge capacity of 10000 m3/s. The dam withholds a 127500000 cubic metre capacity reservoir with a surface area of 12.9 km (8 mi). The reservoir receives water through a channel that originates near the southern end of the Appolonius Sales Reservoir and continues south, skirting the city. The PA IV power house is also underground and is 210 m (689 ft) long, 52 m (170.6 ft) high and 24 m (78.7 ft) wide. It contains six 410.4 MW generators for an installed capacity of 2,462.4 MW. Each generator is a SíncronoVertical-type manufactured by Siemens and utilizes vertical shaft Francis turbines that were manufactured by Voith.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK