Wave power And the classification... construction and working of 1. Salter duck 2. Oscillating water column 3. Dolphin type

1. WAVE POWER

2. What is wave power…?
Wave energy (or wave power) is the transport and capture of energy by ocean surface
waves. The energy captured is then used for all different kinds of useful work, including
electricity generation, water desalination, and pumping of water.

3. WAVE ENERGY CONSERVATION DEVICES
Wave energy converters are devices that convert the kinetic and potential
energy associated with a moving ocean wave into useful mechanical or
electrical energy.
Wave energy converters can provide clean energy to power the electrical
grid as well as many other applications such as propulsion for ocean vehicles
or pumping for seawater desalination etc.

4. Wave energy converters can generally be classified into…
 Salter duck
 Oscillating water column
 Dolphin type
 Point absorbers
 Terminators &
 Attenuators

5. THE SALTER’S
NODDING
DUCK

6. It was 1974 when Stephen Salter, a professor at Edinburgh University, first
introduced a unique wave-energy conversion concept with efficiencies approaching
90% in two-dimensional sinusoidal waves.

7. Several devices have been designed to harness
energy from the waves. The ‘Salter Duck’ is an
example.
The duck ‘bobs’ up and down on waves and a
special turbine inside converts this movement
into electricity.
The Salter Duck is as large as a Double Decker
bus. They are arranged in set patterns in the sea,
to take advantage of wave formations.

8. CONSTRUCTION

9. WORKING
The device is designed with a paunch shaped such that the dynamic pressure caused by the
wave-induced water particle motions efficiently forces the duck to rotate about its axis of
rotation.
The changing in hydrostatic pressure also contributes to the rotation by causing the
buoyant fore body near the beak to rise and fall.
Since both of this pressure-induced motion is in phase, the nodding duck can convert not
only the kinetic energy but also the potential energy of the wave into mechanical rotational
energy.
The rotational motion then is transformed into electricity by a hydraulic-electricity
subsystem.

10. THE OSCILLATING WATER
COLUMN (OWC)

11. An oscillating water column uses a
large volume of moving water as a
piston in a cylinder. Air is forced out of
the column as a wave rises and fresh
air is drawn in as the wave falls. This
movement of air turns a weir turbine at
the top of the column.

12. CONSTRUCTION

13. WORKING
The OWC consists of a chamber opening to the sea level that is below the water surface.
The wave motion provides momentum for the water to come into the chamber.
As the water moves inside the chamber, the air inside the chamber will be compressed and hence will
escape to the atmosphere through a turbine.
As the water retreats, the air then drawn in through a turbine.
A low-pressure Well turbine is used to convert air linear motion into rotation motion and hence
provides power output.
The reason for using the well turbine is that it can rotates in only one direction in spite of the
direction of air motion.
The advantage of using a OWC system is that simplicity and robustness.

14. THE DOLPHIN
TYPE WAVE
POWER
GENERATOR

15. CONSTRUCTION

16. MAJOR
COMPONENTS
A dolphin
A float
A connecting rod and
Two electrical generators

17. WORKING
This device uses the float which has two motions.
This first is a rolling motion about its own fulcrum with the connecting
rod and the other is a nearly vertical or heaving motion about the
connecting rod fulcrum.
It causes relative revolving moments between the connecting rod and
stationary dolphin.
In both cases , the moments are amplified and converted by gears into
continuous rotary motion that drive the two electrical generators.

18. PURPOSE OF TWO GENERATORS
A “stationary generator”, installed on the top of the structure, collects wave energy from
the “connecting rod” with rolling motion. This generator has a gear arrangement which
rotates the rotor to generate electric power.
The “buoy” which is at the other end of the connecting rod float has two motions, namely
rolling motion and oscillatory motion. The “floating generator” collects wave energy from
the buoy through a gear arrangement and generates electric power continuously.

19. OPERATIONAL
EXPERIENCE…

20. THE EXPERIENCE WITH OCEAN
ENERGY
 Wave and tidal energy systems harness natural oceanic flows among
the most powerful and constant dynamics on the earth.
 To generate electricity,
 A variety of companies, utilities, universities, and governments are
working to realize the promise of consistent and predictable ocean
energy, which currently accounts for a fraction of global electricity
generation.

21.  While the ocean’s perpetual power makes wave and tidal energy
possible, it also creates obstacles.
 Operating in harsh and complex marine environments is a
challenge from designing systems to building installations to
maintaining them over time.
 It is more expensive than producing electricity on solid ground.

22.  Despite decades of work, marine technologies are still in early
development and lag well behind solar and wind.
 Tidal energy is more established than wave, with more projects in
operation today.
 Across the world, a variety of wave-energy technologies are being
tested and honed, in pursuit of the ideal design for converting
waves’ kinetic energy into electricity.
 Wave and tidal energy is currently the most expensive of all
renewables. Still, the opportunity of marine-based energy is massive.

23. Conclusion
Realizing that, it would require a substantial
Investment and expanded Research.

24. THANK YOU…