Outline
MAE 493R/593V- Renewable Energy Devices
Hydro-Power
• Basics of hydro-turbines
• Benefits and environmental impacts of hydropower
generation
• Current status of hydropower generation in USA
http://hidden-technology.org/Common-Alternative-Energy-Sources.php
http://www.flickr.com/photos/royal65/3167556443/
Hydroelectric Power Generation
Hydroelectric Power Generation
¾ Hydropower is "water power“. Hydroelectric power is the electricity
generated using water power.
Terminology (Jargon)
• Head
9 Water must fall from a higher elevation to a lower one to release its
stored energy.
9 The difference between these elevations (the water levels in the
forebay and the tailbay) is called head
• Dams: three categories
9 high-head (800 or more feet)
9 medium-head (100 to 800 feet)
9 low-head (less than 100 feet)
http://www.wapa.gov/crsp/info/harhydro.htm
Hydroelectric Power Generation
Types of Hydroelectric Installation
Hydroelectric Power Generation
Power of hydroelectric plants
Potential energy stored in a reservoir becomes kinetic energy, and then
converted to mechanical energy (shaft work) by a hydro-turbine, and then
turned into electrical energy by a generator.
e = g×H
•
Pstored = m gH
•
Pactual = η m gH
• P - power (kW)
• g - gravitational acceleration (9.81 m/s2)
• H - effective head (m)
•
•
m - mass flow rate (kg/s)
• η - turbo-generator efficiency (0<n<1)
Boyle, Renewable Energy, 2nd edition, Oxford University Press, 2003
Hydroelectric Power Generation
Hydroelectric Power Generation
Types of Hydropower Turbines
Efficiency of Hydropower Plants
• Hydropower is very efficient
• Typical energy losses are due to
9 Frictional drag and turbulence of flow
9 Friction and magnetic losses in turbine & generator
• Overall efficiency ranges from 75~95%
Boyle, Renewable Energy, 2nd edition, Oxford University Press, 2003
Hydroelectric Power Generation
Boyle, Renewable Energy, 2nd edition, Oxford University Press, 2003
Hydroelectric Power Generation
Kaplan Turbine Schematic
Francis Turbine – Grand Coulee Dam
Source: Wikipedia.com
Hydroelectric Power Generation
Types of Hydropower Turbines
• Kaplan
Hydroelectric Power Generation
Types of Hydropower Turbines
2 < H < 40
• Francis 10 < H < 350
• Pelton
50 < H < 1300
• Turgo
50 < H < 250
(H = head in meters)
Boyle, Renewable Energy, 2nd edition, Oxford University Press, 2003
Boyle, Renewable Energy, 2nd edition, Oxford University Press, 2003
Hydroelectric Power Generation
Hydroelectric Power Generation
Impoundment:
This the most common type of hydroelectric power plant. It uses a dam to
store river water in a reservoir. Water released from the reservoir flows
through a turbine, spinning it, which in turns a generator to produce electricity.
Three types of hydropower facilities:
‰ Impoundment
‰ Diversion
‰ Pumped storage
By courtesy of Richard Nelson
Hydroelectric Power Generation
Diversion:
Also called run-of-river, facility channels a portion of a river through a canal
or penstock. It may not require the use of a dam
e.g. Niagara Falls
Source: http://www.daviddarling.info/encyclopedia/H/AE_hydroelectric_power.html
Hydroelectric Power Generation
Pumped Storage:
When energy storage is needed, a facility pumps water from a lower reservoir
to an upper reservoir. During periods of high electrical demand, the water is
released back to generate electricity.
Source: http://www.daviddarling.info/encyclopedia/H/AE_hydroelectric_power.html
Hydroelectric Power Generation
Cabin Creek Pumped Hydro (Colorado)
• Completed 1967
• Capacity – 324 MW
9 Two 162 MW units
• Purpose – energy storage
9 Water pumped uphill at night
• Low usage – excess base load capacity
Source: http://www.tva.gov/power/pumpstorart.htm
Hydroelectric Power Generation
Advantages
¾ a clean fuel source, free of pollution.
¾ a domestic source of energy.
¾ relies on the water cycle, which is driven by the sun, thus it's renewable
power source.
¾ engineers can control the flow of water through the turbines to produce
electricity on demand.
¾ impoundment hydropower creates reservoirs that offer a variety of
recreational opportunities, notably fishing, swimming, and boating. Other
benefits may include water supply and flood control.
9 Water flows downhill during day/peak periods
9 Helps Xcel to meet surge demand
• E.g., air conditioning demand on hot summer days
• Typical efficiency of 70 – 85%
Water Cycle
Source: DOE
Source: http://www.daviddarling.info/encyclopedia/H/AE_hydroelectric_power.html
Hydroelectric Power Generation
Hydroelectric Power Generation
Disadvantages
Large Dams in the World
¾ High investment costs
Name
¾ Hydrology dependent (precipitation)
Country
Year
Max
Generation
Annual
Production
Three Gorges
China
2009
18,200 MW
¾ Risk at inundation of land and wildlife habitat
Itaipú
Brazil/Paraguay
1983
12,600 MW 93.4 TW-hrs
Guri
Venezuela
1986
10,200 MW
¾ Loss or modification of fish habitat
Grand Coulee
United States
1942/80
46 TW-hrs
6,809 MW 22.6 TW-hrs
¾ Fish entrainment or passage restriction
Sayano
Shushenskaya
Russia
1983
6,400 MW
¾ change in reservoir and stream water quality
Robert-Bourassa
Canada
1981
5,616 MW
Churchill Falls
Canada
1971
5,429 MW
¾ Displacement of local populations
Iron Gates
Romania/Serbia
1970
2,280 MW 11.3 TW-hrs
Source: http://ga.water.usgs.gov/edu/wuhy.html
Hydroelectric Power Generation
35 TW-hrs
“Hydroelectricity,” Wikipedia.org
Hydroelectric Power Generation
Three Gorges Dam Location Map
Three Gorges Dam
The dam stretches 7,661 feet long, 331 feet high and 377 feet wide
http://china-tourism.org/
Source: enchantedLearning.com
Hydroelectric Power Generation
Hydroelectric power generation in the world
Worldwide hydropower produced 3,288 TWh, just over 16% of global
electricity production in 2008, and the overall potential for hydropower is
estimated to be >16,400 TWh/yr.
Source: http://www.iea.org/
Hydroelectric Power Generation
Ten largest hydroelectric producers in 2009
Source: Wikipedia
US Energy production from wind
US Energy production from wind
US energy cost
U.S. Energy Production and Consumption (2009)
U.S. Energy cost (2009)
Source: http://www1.eere.energy.gov/maps_data/pdfs/eere_databook.pdf
Hydroelectric Power Generation
Estimates of US Hydro Construction
• Study of 2000 potential US hydro sites
• Potential capacities from 1-1300 MW
• Estimated development costs
9 $2,000-4,000 per kW
9 Civil engineering 65-75% of total
9 Environmental studies & licensing 15-25%
9 Turbo-generator & control systems ~10%
9 Ongoing costs add ~1-2% to project inflation
Hall et al. (2003), Estimation of Economic Parameters of US Hydropower Resources, Idaho National Laboratory
hydropower.id.doe.gov/resourceassessment/ pdfs/project_report-final_with_disclaimer-3jul03.pdf
Source: http://www1.eere.energy.gov/maps_data/pdfs/eere_databook.pdf