tidal

1. Tidal Power
Methods of Extraction
Patrick Dunlap

2. Definition and Motivation
 What is Tidal Energy?
 Energy contained in a tide, especially that which can
be converted to electricity.
 Why Tidal Energy?
 Declining availability of fossil fuels and global
climate change.

3. Tidal Theory
 Energy Source
 Tidal Cycle
 Amplitude

4. Traditional Method
 Harnesses Potential
Energy within tide

5. Current Plants
Country Site Installed
Power (MW)
Basin Area
(km2)
Mean Tide (m)
France La Rance 240 22 8.55
Russia Kislaya Guba .4 1.1 2.3
Canada Annapolis 18 15 6.4
China Jiangxia 3.9 1.4 5.08

6. Disadvantages
 Environmental
 Economical
 Design

7. New Method
 Involves extraction of
kinetic energy from a tide,
given in KE Flux
 Mechanical processes for
extraction are based on the
hydrofoil.

8. Actual Power Output
 Energy Flux equation is
multiplied by a Constant
Cp
 The differential dA is
now representative of the
sweep are of the blades

9. Site Selection
 High average velocity
(currently looking at > 3
m/s)
 High local energy
demand
 Within Current
Technical Limits

10. Comparison to Wind
 Advantages
 Density
 Predictability
 Aesthetics
 Disadvantages
 Scale
 Construction

11. Current Projects
 In August SeaGen, a 1.2
MW, dual turbine unit
will be connected to the
power grid
 2.25 MW turbine will
supply Portugal
 Last December two
turbines installed in NY’s
East River

12. References
 Tidal Energy, AM Gorlov, 2001
 Choosing and Evaluating sites for Tidal Energy
Evaluation, Byrden, Proceeding of the Institute of
Mechanical Engineers, V 218
 Tapping the Power of the Seas, Economist, V383
 Tidal Current Energy Extraction: Hydrodynamic
Resource Evaluation, Couch, Proceeding of the
Institute of Mechanical Engineers, V 220
 www.wikipedia.org