3. Countries with Most Dams
•
•
•
•
•
•
China (~24,000 dams, about 45% of total)
United States (6600)
India (4300)
Countries with Most Hydro Generation
•China
145 GW
Japan (2700)
•Canada
89
•United States
80
Spain
•Brazil
69
•Russia
45
•India
34
Canada
•
T. Ferguson,
University of
Japan
•Norway
•France
Sources: Sustainable Energy, Wikipedia
27
27
25
5. Largesse of Installations
Three Gorges Dam
Yangtze River, China
23,000 MW
Grand Coulee Dam
Columbia River, US
6,500 MW
T. Ferguson,
University of
6. Energy Conversion Principles
Power available from 1 cubic meter of water
falling through 1 meter every second:
P = Energy per unit of Time
= mgh
= 1000 kg X 9.8 m/s2 X 1 m/ 1 s
= 9800 Joules/s
= 9800 W
= 9.8 kW
So, for every cubic meter of water per meter of
Drop per second,
9.8 kW of power is available
T. Ferguson,
University of
7. Energy Conversion Principles
Impoundment (e.g. Grand Coulee)
1. Cubic meter of Water (ρ= 1000 kg/m3 or 62.4 lb/ft3)
Pond or
Reservoir
Z = head = 160 m
2. PE = mgh
or PE/m3 = ρgZ
3. For Grand Coulee,
PE/m3 = 1000 kg/m3
X 9.8 m/s2
X 160 m
= 1.6 E 6 J
T. Ferguson,
University of
Discharge or
Tailrace
4. For a flowrate of 5000 m3/s,
Power = Potential Energy X Volume/Time X Efficiency
= (1.6 E 6 J) X (5000 m3) X (s-1) X (0.8)
= 6.4 E 9 J/s = 6400 MW
8. Energy Conversion Principles
Run of River (e.g. Limestone Station, MHEB)
1. Flow rate through station matches natural flow rate of river (5100 m 3/s)
Forebay
Z = 27.6 m
2. Minimal static head: PE = 1000 kg/m3
X 9.8 m/s2
X 27.6 m
= 2.7 E 5 J
PowerPE = PE X Flowrate X Eff
= 1.1 E 9 J/s = 1100 MW
T. Ferguson,
University of
3. Nameplate capacity
= 1340 MW
11. Grand Coulee Powerhouse Cross-section
1.
2.
3.
4.
5.
Excavation
Penstock
Trashracks
Vert. Axis
Turbine
Runner
T. Ferguson,
University of
12. Turbine-Generator
1. Typical clearance of runner
to scroll case wall < 1 mm
2. Wicket gates
3. Stator/Rotor
4. Reaction turbine
T. Ferguson,
University of
Source: Sustainable
Energy, p 539.
13. Manitoba Hydro
AC
1. Length = 900 km
2. 18,432 thyristors (BP2)
3. 4 cm diameter cable
Bipole 1
+ 450 kVDC
~
Rectifier
Bipole 2
+ 500 kVDC
Inverter
AC (Eastern
Interconnection)
T. Ferguson,
University of
Source: Manitoba Hydro
Limestone
15. Future in US is Uncertain
T. Ferguson,
University of
16. Hydroelectric in Developing
Countries
• Western Uganda: 60 kW run of river system for
US$15,000 ($250/kW)
• Uganda planning more microhydros
• Primary source today is 200 MW hydro; only 5%
of population served; drought afflicted
• Microhydros: <100 kW; $200-$500/kW; impulse
turbines
• China has ~ 42,200 microhydros (28 GW)
T. Ferguson,
University of
Source: IEEE Spectrum, May 2007, pp 32-37.