Problematic largest hydropower
project
Radomír Goňo
VŠB - Technical university of Ostrava
Department of Electrical Power Engineering
Introduction
The Three Gorges Dam
The Three Gorges Dam
The Three Gorges Dam
Comparison of giants
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The Three Gorges Dam, Yangtze river in China
Comparison of giants
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Water power plant Itaipu Binational, Parana river, Brazil and Paraguay
Comparison of giants
Parameters
Itaipu
Three Gorges
Number of turbines
20 Francis (700MW)
32 Francis (700MW)
Turbine diameter (m)
8.6
9.7
Maximum power (GW)
14
22.4
Electricity generation (TWh/year)
93
100
Discharge capacity (m3/s)
62,200
102,500
Reservoir length (km)
170
600
Reservoir surface area (km2)
1,350
1,084
Dam wall length (m)
7,700
2,309
Dam wall elevation (m)
196
181
Relocation of residents (mil.)
4
1.24
Project History
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1919 - the dam was originally envisioned
1932 - Nationalist government (Chiang Kai-shek),
preliminary work on plans
1939 - Japanese military forces occupied Yichang and
surveyed the area, Otani plan, was completed
1944 - involvement from the United States
1949 - communist victory, Mao Zedong supported the
project, but the Gezhouba Dam was begun first
1980s - plans were revived
1992 - dam was approved by the National People's
Congress
1994-12-14 - the construction started
2003 - the first generator started working
2008 - the last main generator was completed
dam is expected to become fully operational until 2011
Project Scale and Economics
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The dam body was divided into the left side, the spill way, and the right side
The underground power plant under construction is hidden in the mountains
Dam wall
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The project used 27,200,000 m3 of concrete, 463,000 t of steel, and moved
about 102,600,000 m3 of earth
The reservoir created by the TGD
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made of concrete
2,309 m long
181 m high
115 m thick on the bottom
40 m thick on top
660 km in length
1.12 km in width on average
contains 39.3 km3 of water
surface area 1,045 km²
flooded 632 km² of land
cost 180 billion yuan will be recovered when the dam has generated 1,000
TWh of electricity - 10 years after the dam starts full operation
Electricity Generation
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total capacity 22,500 MW
34 generators
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32 main, 700 MW each
2 plant power generators, 50 MW each
annual electricity generation 100 TWh
generators weighs 6,000 t
flow rate between 600 m3/s and 950 m3/s
Francis turbines
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diameter of each turbine is 9.7/10.4 m (VGS
design/Alstom's design)
speed 75 rpm
Electricity Generation
Electricity Generation
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Generator
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normal rated power 778 MVA
maximum power 840 MVA
power factor 0.9
voltage 20 kV
stator outer diameter 21.4/20.9 m
stator inner diameter 18.5/18.8 m
stator height 3.1/3 m
the biggest stator in the world
load 5050/5500 t
average efficiency of the generators is over 94%,
and the highest is 96.5%.
Electricity Generation
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Rotor
Power Distribution
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500 kV DC transmission lines 7,200 MW
500 kV AC transmission lines 12,000 MW.
500 kV DC transmission line 3,000 MW
TGP was expected to provide 10% of the
electricity consumed in China. However,
China’s demand for electricity has increased at
a higher rate than was planned; if it were fully
operational now, it would support only about
3% of China's total electricity consumption
Power Distribution
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Transformer
Operation
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Yangtze River flow
Contributions
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Reduction of Emission
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reduction the coal consumption by 31
million t/year
100 million t of greenhouse gas
millions t of dust
one million t of sulfur dioxide
370,000 t of nitric oxide
10,000 t of carbon monoxide
significant amount of mercury
transport about 31 million t of coal
Contributions
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Waste Management
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50 waste-water treatment plants had been
installed
65% of the waste water is treated
32 deposition land sites were completed
Flood Control and Drought Relief
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flood storage capacity is 22 km3 (100 years)
discharges its reservoir during the dry
season
water level upstream drops from 175 m to
145 m
Contributions
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Navigation
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ship locks
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two ship locks is made up of five stages
four hours in total to transit
vessel capacity of 10,000 t
locks are 280 m long, 35 m wide and 5 m deep
increase river shipping from ten million to 100 million t annually
transportation costs cut by 30%
shipping is safer
freight capacity of the river increased six times
cost of shipping was reduced by 25%
ship lift
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lifting ships of up to 3,000 t
vertical distance 113 m,
size of the ship lift's basin is 120x18x3.5 m
the ship lift will take 40 minutes
ship lift had to be designed to work properly even if the water levels
varied by 12 m on the lower side, and 30 m on the upper side
construction started in 2007 and will be completed in 2014
Problematic Issues
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water quality
detriments to
wildlife
potential
riverbank
collapses
potential silt
related falling of
coastal areas
Problematic Issues
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Relocation of Residents
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Affecting Biodiversity
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1.24 million residents was relocated
endangered Siberian Crane
extinction of Yangtze river dolphin
high levels of pollution in the Yangtze
Effect on Local Culture
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reservoir has flooded some 1,300 archaeological
sites
cultural and historical relics are being moved but
some were flooded
Problematic Issues
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Erosion and Sedimentation
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the dam sits on a seismic fault (?)
80% of the land is experiencing erosion - 40 million
tons of sediment annually
silt in the reservoir
 reduce silt in the Yangtze Delta
 reduce the effectiveness of electricity generation
 the lack of silt deposited in the peninsula could
result in erosion and sinking of coastal areas
 downstream riverbanks more vulnerable to flooding
 the less sediments the more vulnerable is Shanghai
to inundation
Problematic Issues
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National Security
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Structural Integrity
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high-value target
after the first filling of the reservoir, 80 visible cracks
were observed
Earthquakes and Landslides
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potential for earthquake-induced peak ground
acceleration coupled with the immense weight of the
reservoir water, could cause breaching
erosion, induced by rising water, causes frequent
major landslides that have led to noticeable
disturbance in the reservoir surface
Problematic Issues
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Damming Projects Upstream - China
plans to build a series of dams
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maximize the utility of the TGD
cut down on sedimentation
capacity of four dams is 38,500 MW
Problematic Issues
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New plans 38.5 GW
Questions?
Thank you for your attention.
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Three Gorges Project