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Three Gorges Dam

Three Gorges Dam
长江三峡水利枢纽工程
The dam in September 2009
Location in China
Country China
Location Sandouping, Yiling, Hubei
Coordinates
Purpose Power, flood control, navigation
Status Operational
Construction began December 14, 1994
Opening date 2008
Construction cost ¥180 billion (US$26 billion)
Owner(s) China Three Gorges Corporation)
Dam and spillways
Type of dam Gravity dam
Impounds Yangtze River
Height 181 m (594 ft)
Length 2,335 m (7,661 ft)
Width (crest) 40 m (131 ft)
Width (base) 115 m (377 ft)
Spillway capacity 116,000 m3/s (4,100,000 cu ft/s)
Reservoir
Creates Three Gorges Reservoir
Total capacity 39.3 km3 (31,900,000 acre·ft)
Catchment area 1,000,000 km2 (390,000 sq mi)
Surface area 1,084 km2 (419 sq mi)[1]
Max. length 600 km (370 mi)[2]
Normal elevation 175 m (574 ft)
Power station
Commission date 2003–2012
Type Conventional
Hydraulic head

Rated: 80.6 m (264 ft)
Maximum: 113 m (371 ft)[1]

Power generation
Nameplate capacity 22,500 MW
Capacity factor 45%
Annual generation 98.8 TWh (356 PJ) (2014)
Turbines 32 × 700 MW
2 × 50 MW Francis-type

The Three Gorges Dam is a world's largest power station in terms of installed capacity (22,500 MW). The dam is the largest operating hydroelectric facility in terms of annual energy generation, generating 83.7 TWh in 2013 and 98.8 TWh in 2014, while the annual energy generation of the Itaipú Dam in Brazil and Paraguay was 98.6 TWh in 2013 and 87.8 in 2014.[3][4][5]

Except for a ship lift, the dam project was completed and fully functional as of July 4, 2012,[6][7] when the last of the main water turbines in the underground plant began production. Each main water turbine has a capacity of 700 MW.[8][9] The dam body was completed in 2006. Coupling the dam's 32 main turbines with two smaller generators (50 MW each) to power the plant itself, the total electric generating capacity of the dam is 22,500 MW.[8][10][11]

As well as producing electricity, the dam is intended to increase the Yangtze River's shipping capacity and reduce the potential for floods downstream by providing flood storage space. The Chinese government regards the project as a historic engineering, social and economic success,[12] with the design of state-of-the-art large turbines,[13] and a move toward limiting greenhouse gas emissions.[14] However, the dam flooded archaeological and cultural sites and displaced some 1.3 million people, and is causing significant ecological changes, including an increased risk of landslides.[15] The dam has been a controversial topic both domestically and abroad.[16]

Three Gorges Dam
Simplified Chinese 长江三峡大坝
Traditional Chinese 長江三峡大壩

Contents

  • History 1
  • Composition and dimensions 2
  • Economics 3
  • Power generation and distribution 4
    • Generating capacity 4.1
    • Generators 4.2
    • Generator installation progress 4.3
    • Output milestones 4.4
    • Distribution 4.5
  • Environmental impact 5
    • Emissions 5.1
    • Erosion and sedimentation 5.2
    • Earthquakes and landslides 5.3
    • Waste management 5.4
    • Forest cover 5.5
    • Wildlife 5.6
  • Floods, agriculture, industry 6
  • Navigating the dam 7
    • Locks 7.1
    • Ship lifts 7.2
    • Portage railways 7.3
  • Relocation of residents 8
  • Other effects 9
    • Culture and aesthetics 9.1
    • National security 9.2
    • Structural integrity 9.3
  • Upstream dams 10
  • See also 11
  • References 12
  • External links 13

History

In his poem "Swimming" (1956), engraved on the 1954 Flood Memorial in Wuhan, Mao Zedong envisions "walls of stone" to be erected upstream.[17]

A large dam across the Yangtze River was originally envisioned by Japanese military forces occupied Yichang and surveyed the area. A design, the Otani plan, was completed for the dam in anticipation of a Japanese victory over China.

In 1944, the United States Bureau of Reclamation chief design engineer, John L. Savage, surveyed the area and drew up a dam proposal for the 'Yangtze River Project'.[20] Some 54 Chinese engineers went to the U.S. for training. The original plans called for the dam to employ a unique method for moving ships; the ships would move into locks located at the lower and upper ends of the dam and then cranes with cables would move the ships from one lock to the next. In the case of smaller water craft, groups of craft would be lifted together for efficiency. It is not known whether this solution was considered for its water-saving performance or because the engineers thought the difference in height between the river above and below the dam too great for alternative methods.[21] Some exploration, survey, economic study, and design work was done, but the government, in the midst of the Chinese Civil War, halted work in 1947.

After the 1949 Communist takeover, Mao Zedong supported the project, but began the Gezhouba Dam project nearby first, and economic problems including the Great Leap Forward and the Cultural Revolution slowed progress. After the 1954 Yangtze River Floods, in 1956, Mao Zedong authored "Swimming", a poem about his fascination with a dam on the Yangtze River. In 1958, after the Hundred Flowers Campaign, some engineers who spoke out against the project were imprisoned.[22]

During the 1980s, the idea of a dam reemerged. The National People's Congress approved the dam in 1992: out of 2,633 delegates, 1,767 voted in favour, 177 voted against, 664 abstained, and 25 members did not vote.[23] Construction started on December 14, 1994.[24] The dam was expected to be fully operational in 2009, but additional projects, such as the underground power plant with six additional generators, delayed full operation until May 2012.[11][22] The ship lift was expected to be completed in 2014.[25] The dam had raised the water level in the reservoir to 172.5 m (566 ft) above sea level by the end of 2008 and the designed maximum level of 175 m (574 ft) by October 2010.[26][27]

Map of the location of the Three Gorges Dam and the most important cities along the Yangtze River

Composition and dimensions

Made of concrete and steel, the dam is 2,335 m (7,661 ft) long and the top of the dam is 185 metres (607 ft) above sea level. The project used 27.2 million cubic metres (35.6×10^6 cu yd) of concrete (mainly for the dam wall), 463,000 tonnes of steel (enough to build 63 Eiffel Towers) and moved about 102.6 million cubic metres (134.2×10^6 cu yd) of earth.[28] The concrete dam wall is 181 metres (594 ft) high above the rock basis.

When the water level is at its maximum of 175 metres (574 ft) above sea level, which is 110 metres (361 ft) higher than the river level downstream, the dam reservoir is on average about 660 kilometres (410 mi) in length and 1.12 kilometres (3,700 ft) in width. It contains 39.3 km3 (31,900,000 acre·ft) of water and has a total surface area of 1,045 square kilometres (403 sq mi). On completion, the reservoir flooded a total area of 632 square kilometres (244 sq mi) of land, compared to the 1,350 square kilometres (520 sq mi) of reservoir created by the Itaipu Dam.[29]

Economics

The government estimated that the Three Gorges Dam project would cost 180 billion yuan (US$22.5 billion).[30] By the end of 2008, spending had reached 148.365 billion yuan, among which 64.613 billion yuan was spent on construction, 68.557 billion yuan on relocating affected residents, and 15.195 billion yuan on financing.[31] It is estimated that the construction cost will be recovered when the dam has generated 1,000 terawatt-hours (3,600 PJ) of electricity, yielding 250 billion yuan. Full cost recovery is expected to occur ten years after the dam starts full operation.[30]

Funding sources include the Three Gorges Dam Construction Fund, profits from the

  • China Three Gorges Corporation
  • China Yangtze Power Co., Ltd.
  • Three Gorges Power Plant Animation on YouTube

External links

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  20. ^ John Lucian Savage Biography by Abel Wolman & W. H. Lyles, National Academy of Science, 1978.
  21. ^ //books.google.com/books?id=7SADAAAAMBAJ&pg=PA98 Popular Science, July 1946
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  35. ^ THREE GORGES DAM by Matthew Morioka, Alireza Abrishamkar, Yve Kay CEE 491
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  69. ^ a b c d translation
  70. ^ Topping, Audrey Ronning. Environmental controversy over the Three Gorges Dam. Earth Times News Service.
  71. ^ a b c d e Qing, Dai, 9. The River Dragon Has Come!: The Three Gorges Dam and the Fate of China's Yangtze River and Its People (East Gate Book). Armonk, New York: M.E. Sharpe, 1997.
  72. ^
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  76. ^ a b
  77. ^ translation
  78. ^ Peter Collins, Falling Here, Rising There, The World in 2008, The Economist, p. 63.
  79. ^ Li, Long (1989). Environmental planning of large-scale water projects: The Three Gorges Dam case, China (M.A. thesis) Wilfrid Laurier University
  80. ^ Wu, Jianguo, et al. "Three-Gorges Dam— Experiment in Habitat Fragmentation?" Science 300-5623 (May 23, 2003): 1239–1240.
  81. ^ Chetham, Deirdre. "Before the Deluge: The Vanishing World of the Yangtze's Three Gorges." New York: Palgrave Macmillan, 2002.
  82. ^ Chetham, Deirdre. "Before the Deluge: The Vanishing World of the Yangtze's Three Gorges."
  83. ^ Xie, Ping. "Three-Gorges Dam: Risk to Ancient Fish." Science 302-5648 (Nov 14, 2003): 1149.
  84. ^ Mary Ann Toy, The Age AU, "Three Gorges Dam 'could be huge disaster'", 10-13-07, retrieved 10-13-07.
  85. ^
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  90. ^ Dai, Qing. Yangtze! Yangtze!. UK: Earthscan Ltd, 1994., 184
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  95. ^ Three Gorges Dam will meet the first large-scale flood since being completed July 20, 2010. Retrieved July 20, 2010.
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  109. ^ a b 湖北议案提案:提升三峡翻坝转运能力 ("Hubei's Proposal: raise the Three Gorges dam-bypassing transportation capacity"), 2013-03-17 (Chinese)
  110. ^ 三峡翻坝铁路前期工作启动 建成实现水铁联运 (Preliminary work started on the Three Gorges Portage Railways. The project will implement a water-rail connection.) 2012-10-12
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  128. ^ Steven Hannon. The 1983 Flood at Glen Canyon
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References

See also

[132] Baihetan is preparing for construction and Wudongde is seeking government approval. Another eight dams are in the midstream of the Jinsha and eight more upstream of it.[131] In order to maximize the utility of the Three Gorges Dam and cut down on sedimentation from the

Longitudinal profile of upstream Yangtze River

Upstream dams

[129] The submerged spillway gates of the dam might pose a risk of [127][126][125] Days after the first filling of the reservoir, around 80 hairline cracks were observed in the dam's structure.

Structural integrity

The notion that the military in Taiwan would seek to destroy the dam provoked an angry response from the mainland Chinese media. People's Liberation Army General Liu Yuan was quoted in the China Youth Daily saying that the People's Republic of China would be "seriously on guard against threats from Taiwan independence terrorists."[124]

The [123]

National security

[122] Cultural and historical relics are being moved to higher ground as they are discovered, but the flooding inevitably covered undiscovered relics. Some sites could not be moved because of their location, size, or design. For example, the [121] The 600 km (370 mi) long reservoir flooded some 1,300 archaeological sites and altered the appearance of the Three Gorges as the water level rose over 300 ft (91 m).

Culture and aesthetics

Other effects

Allegedly, funds for relocating 13,000 farmers around Gaoyang disappeared after being sent to the local government, leaving residents without compensation.[120]

Relocation was completed on July 22, 2008.[112] Some 2007 reports claimed that Chongqing Municipality will encourage an additional four million people to move away from the dam to the main urban area of Chongqing by 2020.[116][117][118] However, the municipal government explained that the relocation is due to urbanization, rather than the dam, and people involved included other areas of the municipality.[119]

As of June 2008, China relocated 1.24 million residents (ending with Gaoyang in Hubei Province) as 13 cities, 140 towns and 1350 villages either flooded or were partially flooded by the reservoir [A_2-M:CR3-1HP:S-15],[111][112][113] about 1.5% of the province's 60.3 million and Chongqing Municipality's 31.44 million population.[114] About 140,000 residents were relocated to other provinces.[115]

Relocation of residents

In late 2012, preliminary work started along both future railway routes.[110]

Plans also exist for the construction of short portage railways bypassing the dam area altogether. Two short rail lines, one on each side of the river, are to be constructed. The 88 kilometer long northern portage railway (北岸翻坝铁路) will run from the Taipingxi port facility (太平溪港) on the northern side of the Yangtze, just upstream from the dam, via Yichang East Railway Station to the Baiyang Tianjiahe port facility in Baiyang Town (白洋镇), below Yichang.[109] The 95 kilometer long southern portage railway (南岸翻坝铁路) will run from Maoping (upstream of the dam) via Yichang South Railway Station to Zhicheng (on the Jiaozuo–Liuzhou Railway).[109]

Portage railways

As of May 2014, the ship lift was expected to be completed by July of 2015.[108]

The report said the towers had reached 189 metres of the anticipated 195 metres, the towers would be completed by June 2012 and the entire shiplift in 2015.

In February 2012 Xinhua reported that the four towers that are to support the ship lift had almost been completed.[107]

The ship lift was not yet complete when the rest of the project was officially opened on May 20, 2006.[105][106] In November 2007 it was reported in the local media that construction of the ship lift started in October 2007 and was anticipated to be completed in 2014.[25]

In addition to the canal locks, a [103] and the size of the ship lift's basin will be 120×18×3.5 metres. The ship lift, when completed, will take 30 to 40 minutes to transit, as opposed to the three to four hours for stepping through the locks.[104] One complicating factor is that the water level can vary dramatically. The ship lift must work even if water levels vary by 12 meters (39 ft) on the lower side, and 30 metres on the upper side.

Ship lifts

These locks are staircase locks, whereby inner lock gate pairs serve as both the upper gate and lower gate. The gates are the vulnerable hinged type, which, if damaged, could temporarily render the entire flight unusable. As there are separate sets of locks for upstream and downstream traffic, this system is more water efficient than bi-directional staircase locks.

[69] That is 30 m longer than those on the [101][100] The locks are 280 m long, 35 m wide, and 5 m deep (918 × 114 × 16.4 ft).[99] There are two series of ship locks installed near the dam (). Each of them is made up of five stages, with transit time at around four hours. Maximum vessel size is 10,000 tons.

[98][97]. It is expected that shipping to Chongqing will increase fivefold.Chongqing Ships with much deeper draft will be able to navigate 2,400 kilometres (1,500 mi) upstream from Shanghai all the way to [69] The installation of

The other end of Three gorges dam lock, note the Bridge in the background
Three gorges dam lock view from the road
Ship locks for river traffic to bypass the Three Gorges Dam, May 2004

Locks

Navigating the dam

During the 1998 Yangtze River Floods. The dam's reservoir rose nearly 3 m (9.8 ft) in 24 hours and reduced the outflow to 40,000 m3/s (1,400,000 cu ft/s) in discharges downstream, effectively alleviating serious impacts on the middle and lower river.[95][96]

Since the filling of the reservoir in 2003, the Three Gorges Dam has supplied an extra 11 cubic kilometres of fresh water to downstream cities and farms during the dry season.[94]

The dam discharges its reservoir during the dry season between December and March every year.[92] This increases the flow rate of the river downstream, and provides fresh water for agricultural and industrial usage. It also improves shipping conditions. The water level upstream drops from 175 m to 145 m,[93] preparing for the rainy season. The water also powers the Gezhouba Dam downstream.

In early August 2009, the largest flood in five years passed through the dam site. The dam limited the water flow to less than 40,000 cubic metres (52,000 cu yd) per second, raising the upstream water level from 145.13 metres on August 1, 2009, to 152.88 on August 8, 2009. 4.27 cubic kilometres of flood water were captured and the river flow was cut by as much as 15,000 cubic metres per second.[49]

In 1998 a flood in the same area caused billions of dollars in damage; 2,039 km2 (787 sq mi) of farm land were flooded. The flood affected more than 2.3 million people, killing 1,526.[91]

The reservoir's flood storage capacity is 22 cubic kilometres (18,000,000 acre·ft). This capacity will reduce the frequency of major downstream flooding from once every ten years to once every 100 years. The dam is expected to minimize the effect of even a "super" flood.[87][88] In 1954 the river flooded 193,000 km2 (74,518 sq mi), killing 33,169 people and forcing 18,884,000 people to move. The flood covered Wuhan, a city of eight million people, for over three months, and the Jingguang Railway was out of service for more than 100 days.[89] The 1954 flood carried 50 cubic kilometres (12 cu mi) of water. The dam could only divert the water above Chenglingji, leaving 30 to 40 km3 (7.2 to 9.6 cu mi) to be diverted.[90] Also the dam cannot protect against some of the large tributaries downstream, including the Xiang, Zishui, Yuanshui, Lishui, Hanshui, and the Gan.

An important function of the dam is to control flooding, which is a major problem for the seasonal river of the Yangtze. Millions of people live downstream of the dam, with many large, important cities like Wuhan, Nanjing, and Shanghai situated adjacent to the river. Plenty of farm land and China's most important industrial area are built beside the river.

Floods, agriculture, industry

[86] are guaranteed to be "negatively affected" by the dam.Yangtze sturgeon Yangtze river dolphin. Though it was close to this level even at the start of construction, the dam further decreased its habitat and increased ship travel, which are among the factors causing what will be its ultimate demise. In addition, populations of the baiji of the functional extinction The dam contributed to the [85] Of the 3,000 to 4,000 remaining

[84] Concerns about the potential wildlife impact of the Dam predate the

Wildlife

[78] Research by the

In 1997 the Three Gorges area had 10% forestation, down from 20% in the 1950s.[71]

Forest cover

The dam catalyzed improved upstream wastewater treatment around Chongqing and its suburban areas. According to the Ministry of Environmental Protection, as of April 2007 more than 50 new plants could treat 1.84 million tonnes per day, 65% of the total need. About 32 landfills were added, which could handle 7,664.5 tonnes of solid waste every day.[77] Over one billion tons of wastewater are released annually into the river,[71] which was more likely to be swept away before the reservoir was created. This has left the water looking stagnant, polluted and murky.[76]

Zigui County seat source water protection area in Maoping Town, a few kilometers upstream of the dam

Waste management

Erosion in the reservoir, induced by rising water, causes frequent major Wu River.[75] Also, in the first four months of 2010, there were 97 significant landslides.[76]

Earthquakes and landslides

  • Some hydrologists expect downstream riverbanks to become more vulnerable to flooding.[72]
  • Shanghai, more than 1,600 km (990 mi) away, rests on a massive sedimentary plain. The "arriving silt—so long as it does arrive—strengthens the bed on which Shanghai is built... the less the tonnage of arriving sediment the more vulnerable is this biggest of Chinese cities to inundation..."[73]
  • Benthic sediment buildup causes biological damage and reduces aquatic biodiversity.[74]

The absence of silt downstream has three effects:

Two hazards are uniquely identified with the dam.[70] One is that sedimentation projections are not agreed upon, and the other is that the dam sits on a seismic fault. At current levels, 80% of the land in the area is experiencing erosion, depositing about 40 million tons of sediment into the Yangtze annually.[71] Because the flow is slower above the dam, much of this sediment will now settle there instead of flowing downstream, and there will be less sediment downstream.

Erosion and sedimentation

The dam increased the Yangtze's barge capacity sixfold, reducing carbon dioxide emission by 630,000 tonnes. From 2004 to 2007 a total of 198 million tonnes of goods passed through the ship locks. Compared to using trucking, barges reduced carbon dioxide emission by ten million tonnes and lowered costs by 25%.[69]

From 2003 to 2007, power production equaled that of 84 million tonnes of standard coal, reducing carbon dioxide by 190 million tonnes, sulfur dioxide by 2.29 million tonnes, and nitrogen oxides by 980,000 tonnes.[69]

According to the National Development and Reform Commission of China, 366 grams of coal would produce 1 kWh of electricity during 2006.[66] At full power, Three Gorges reduces coal consumption by 31 million tonnes per year, avoiding 100 million tonnes of greenhouse gas emissions,[67] millions of tonnes of dust, one million tonnes of sulfur dioxide, 370,000 tonnes of nitric oxide, 10,000 tonnes of carbon monoxide, and a significant amount of mercury.[68] Hydropower saves the energy needed to mine, wash, and transport the coal from northern China.

Emissions

Flood mark on Yangtze river
Satellite map showing areas flooded by the Three Gorges reservoir. Compare November 7, 2006 (above) with April 17, 1987 (below)

Environmental impact

The dam was expected to provide 10% of China's power. However, electricity demand has increased more quickly than previously projected. Even fully operational, on average, it supports only about 1.7% of electricity demand in China in the year of 2011, when the Chinese electricity demand reached 4692.8 TWh.[64][65]

[63] Power is distributed over multiple 500

Power distribution and transmission infrastructure cost about 34.387 billion Yuan. Construction was completed in December 2007, one year ahead of schedule.[62]

The State Grid Corporation and China Southern Power Grid paid a flat rate of ¥250 per MWh (US$35.7) until July 2, 2008. Since then, the price has varied by province, from ¥228.7–401.8 per MWh. Higher-paying customers receive priority, such as Shanghai.[60] Nine provinces and two cities consume power from the dam.[61]

Distribution

Annual Production of Electricity
Year Number of
installed units
TWh
2003 6 8.607
2004 11 39.155
2005 14 49.090
2006 14 49.250
2007 21 61.600
2008 26 80.812 [53]
2009 26 79.470 [54]
2010 26 84.370 [55]
2011 29 78.290 [56]
2012 32 98.100 [57]
2013 32 83.270 [58]
2014 32 98.800 [59]

The Three Gorges Dam reached its design-maximum reservoir water level of 175 m (574 ft) for the first time on October 26, 2010, in which the intended annual power-generation capacity of 84.7 TWh was realized.[26] In 2012, the dam's 32 generating units generated a record 98.1 TWh of electricity, which accounts for 14% of China's total hydro generation.[52]

During the November to May dry season, power output is limited by the river's flow rate, as seen in the diagrams on the right. When there is enough flow, power output is limited by plant generating capacity. The maximum power-output curves were calculated based on the average flow rate at the dam site, assuming the water level is 175 m and the plant gross efficiency is 90.15%. The actual power output in 2008 was obtained based on the monthly electricity sent to the grid.[50][51]

By August 16, 2011, the plant had generated 500 TWh of electricity.[45][46] In July 2008 it generated 10.3 TWh of electricity, its first month over 10 TWh.[47] On June 30, 2009, after the river flow rate increased to over 24,000 m3, all 28 generators were switched on, producing only 16,100 MW because the head available during flood season is insufficient.[48] During an August 2009 flood, the plant first reached its maximum output for a short period.[49]

Yangtze River flow rate comparing to the dam intake capacity
Three Gorges Dam annual power output

Output milestones

The 6 underground main generators are also in operation as of May 23, 2012, when the last main generator, No. 27, finished its final test raising capacity to 22.5 GW.[6] After 9 years of construction, installation and testing, the power plant is now fully operational.[11][42][43][44]

The 12 south side main generators are also in operation. No. 22 began operation on June 11, 2007 and No. 15 started up on October 30, 2008.[9] The sixth (No. 17) began operation on December 18, 2007, raising capacity to 14.1 GW, finally surpassing Itaipu (14.0 GW), to become the world's largest hydro power plant by capacity.[38][39][40][41]

The 14 north side main generators are in operation. The first (No. 2) started on July 10, 2003. The north side became completely operational September 7, 2005 with the implementation of generator No. 9. Full power (9,800 MW) was only reached on October 18, 2006 after the water level reached 156 m.[37]

Generator installation progress

The generators are manufactured by two joint ventures. One of them includes Alstom, ABB Group, Kvaerner, and the Chinese company Haerbin Motor. The other includes Voith, General Electric, Siemens (abbreviated as VGS), and the Chinese company Oriental Motor. The technology transfer agreement was signed together with the contract. Most of the generators are water-cooled. Some newer ones are air-cooled, which are simpler in design and manufacture and are easier to maintain.[36]

Three Gorges Dam Francis turbine

The main generators weigh about 6,000 tonnes each and are designed to produce more than 700 MW of power. The designed Francis turbines. Turbine diameter is 9.7/10.4 m (VGS design/Alstom's design) and rotation speed is 75 revolutions per minute. Rated power is 778 MVA, with a maximum of 840 MVA and a power factor of 0.9. The generator produces electrical power at 20 kV. The outer diameter of the generator stator is 21.4/20.9 m. The inner diameter is 18.5/18.8 m. The stator, the biggest of its kind, is 3.1/3 m in height. Bearing load is 5050/5500 tonnes. Average efficiency is over 94%, and reaches 96.5%.[34][35]

Generators

[33] in the mountain south of the dam. The expected annual electricity generation will be over 100 TWh.underground power plant Among those 32 main generators, 14 are installed in the north side of the dam, 12 in the south side, and the remaining six in the [8] Power generation is managed by

Electricity production in China by source. Compare: The fully completed Three Gorges dam will contribute about 100 TWh of generation per year.
  thermofossil
  hydroelectric
  nuclear

Generating capacity

Power generation and distribution

Panorama of the Three Gorges Dam

[32]

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