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WAVE POWER STATION
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CONTENTS
1.WAVES
2. WAVE POWER
3.HOW IT WORKS

• 4. OCEAN WAVE ENERGY TECHNOLOGIES
• Introduction
• -Modern technology
• -Current technology
• a. Buoyant Moored
  Device
• b. Hinged Contour Device
• c.Oscillating Water
  Column.

• - Ocean wave power generator
• Islay wave power station.

5.POTENTIAL
6.CHALLENGES
 
7.ADVANTAGES
8.DISADVANTAGES
9.CONCLUSIONS
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1. WAVES
Waves are generated by wind passing over the sea
organized waves form from disorganized turbulence
because wind pressure pushes down wave troughs
and lifts up wave crests, the latter due to
Bernoullis principle.In general, large waves are
more powerful. Wave size is determined by
wind speed and fetch (the distance over which the
wind excites the waves) and by the depth and
topography of the seafloor (which can focus or
disperse the energy of the waves). A given wind
speed has a matching practical limit over which
time or distance will not produce larger waves.
This limit is called a "fully developed sea."
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2. WAVE POWER
Wave power refers to the energy of ocean surface
waves and the capture of that energy to do useful
work- including electricity generation,
desalination, and the pumping of water (into
reservoirs). Wave power is a form of renewable
energy. Though often co-mingled, wave power is
distinct from the diurnal flux of tidal power and
the steady gyre of ocean currents. Wave power
generation is not a widely employed technology,
and no commercial wave farm has yet been
established
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3. HOW IT WORKS
There are several methods of getting energy
from waves, but one of the most effective works
like a swimming pool wave machine in reverse. At
a swimming pool, air is blown in and out of a
chamber beside the pool, which makes the water
outside bob up and down, causing waves. At a wave
power station, the waves arriving cause the water
in the chamber to rise and fall, which means that
air is forced in and out of the hole in the top
of the chamber.
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4. OCEAN WAVE ENERGY TECHNOLOGIES
A variety of technologies have been proposed to
capture the energy from waves. Some of the more
promising designs are undergoing demonstration
testing at commercial scales.
Wave technologies have been designed to be
installed in nearshore, offshore, and far
offshore locations. Offshore systems are situated
in deep water, typically of more than 40 meters
(131 feet).
While all wave energy technologies are intended
to be installed at or near the water's surface,
they differ in their orientation to the waves
with which they are interacting and in the manner
in which they convert the energy of the waves
into other energy forms, usually electricity. The
following wave technologies have been the target
of recent development.
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Terminator devices extend perpendicular to the
direction of wave travel and capture or reflect
the power of the wave.
Point Absorber Wave Energy Farm

Point absorber
A point absorber is a floating structure with
components that move relative to each other due
to wave action
The oscillating water column is a form of
terminator in which water enters through a
subsurface opening into a chamber with air
trapped above it..
Point Absorber Operation
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Attenuators are long multisegment floating
structures oriented parallel to the direction of
the waves.
Overtopping devices have reservoirs that are
filled by incoming waves to levels above the
average surrounding ocean.
Attenuator Wave Energy Device
Seagoing vessels capture the energy of offshore
waves. These floating platforms create
electricity by funneling waves through internal
turbines and then back into the sea.
"Wave Dragon" Prototype Overtopping Device
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MODERN TECHNOLOGY
Wave power devices are generally categorized by
the method used to capture the energy of the
waves. They can also be categorized by location
and power take-off system. Method types are point
absorber or buoy surfacing following or
attenuator terminator, lining perpendicular to
wave propagation oscillating water column and
overtopping. Locations are shoreline, nearshore
and offshore. Types of power take-off include
hydraulic ram, elastomeric hose pump,
pump-to-shore, hydroelectric turbine, air turbine
and linear electrical generator. Some of these
designs incorporate parabolic reflectors as a
means of increasing the wave energy at the point
of capture.
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CURRENT TECHNOLOGY
 According to the DTI, there are three types of
wave energy collector. These are  a. Buoyant
Moored Devic b. Hinged Contour Device     c.
 Oscillating Water Column
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• Buoyant Moored Device
• This type of device floats on the surface of the
  water or below it. It is moored to the seabed by
  either a taught or loose mooring system. One
  example of this type of device will be discussed,
  the Edinburgh or Salter Duck. The Duck team is
  led by Professor Salter at Edinburgh University.
• The Duck is shown in the figure below. Ducks work
  by independently rotating about a long linkage
  this maintains its stability by out spanning wave
  crests. The front edge of the duck matches the
  wave particle motion. In moderate seas, the more
  cylindrical back portion creates no stern waves
  but when the weather is bad these parts shed
  energy through wave making to the rear. The
  device requires a depth of at least 80 metres and
  uses a system of weights and floats to give
  almost constant tension in the mooring cables.
•  

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b. Hinged Contour Device This type of device
follows the motion of the waves it creates power
using the motion at the joints. It is commonly
moored slackly to hold it in place. One example
of this type of device is the Pelamis WEC that is
being developed by Ocean Power Delivery. As the
Pelamis moves with the waves, the motion is
resisted at the joints by hydraulic rams that
pump high-pressure oil through hydraulic motors
via smoothing accumulators. These motors are used
to drive generators to create power. It has been
said that a 750kW device would be 150m long and
3.5m in diameter and comprise five sections.
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c. Oscillating Water Column (OWC) This method of
generating power from the tide works by using a
column of water as a piston to pump air and drive
a turbine to generate power. This type of device
can be fixed to the seabed or installed on
shore. In Scotland, the Government awarded three
wave energy projects under the Scottish
Renewables Obligation. Only one of these projects
has been realised and is generating power in
Scotland as this pack is being written, this is
the LIMPET 500 on the Island of Islay of the west
coast, enabling the Island to take a step towards
becoming self sufficient in renewable energy.
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OCEAN WAVE POWER GENERATOR
A while back, a Discover Circuits visitor wanted
a simply way to demonstrate how electricity could
be generated from the up and down movement of
ocean waves. The system was to be part of a
science fair project, showing different renewable
energy sources.  I gave this some thought and
came up with the system shown below. It uses a
simple plastic foam float attached to a lever
arm, which is connected to the shaft of an
inexpensive stepper motor, available from
www.jameco.com.
When properly mounted in a tank of water, the
motion of a wave in the tank causes the shaft of
the stepper motor to move. That movement produces
enough electricity to turn on the visible red
LED.
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ISLAY WAVE POWER STATION
The Islay Wave Power Station will provide 0.5MW
of electricity for the island of Islay's grid -
enough to power around 500 homes. Known as LIMPET
500 (Land Installed Marine Powered Energy
Transformer), it was designed and build by
Wavegen and Queen's University, Belfast, with
funding from the EU.Without getting into the
technical details, waves enter a concrete capture
chamber which is set into an excavated rock face
on the island. As water enters and leaves the
chamber with the arrival of each new wave, the
pressure of the air within the chamber increases
and decreases. It is this oscillation of the air
pressure within the chamber which draws air in or
pushes air out of the chamber passing through the
turbine. Whether air is being forced through the
turbine, or drawn back into the chamber through
the turbine, electricity is generated.
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5. POTENTIAL
Good wave power locations have a flux of about 50
kilowatts per meter of shoreline. Capturing 20
percent of this, or 10 kilowatts per meter, is
plausible. Assuming very large scale deployment
of (and investment in) wave power technology,
coverage of 5000 kilometers of shoreline
(worldwide) is plausible. Therefore, the
potential for shoreline-based wave power is about
50 gigawatts. Deep water wave power resources are
truly enormous, but perhaps impractical to
capture.
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6. CHALLENGES

• These are some of the challenges to deploying
  wave power devices
• Efficiently converting wave motion into
  electricity generally speaking, wave power is
  available in low-speed, high forces, and the
  motion of forces is not in a single direction.

• 2. Constructing devices that can survive storm
  damage and saltwater corrosion likely sources of
  failure include seized bearings, broken welds,
  and snapped mooring lines.

• 3. High total cost of electricitywave power will
  only be competitive when the total cost of
  generation is reduced. The total cost includes
  the primary converter, the power takeoff system,
  the mooring system, installation maintenance
  cost, and electricity delivery costs.

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7. ADVANTAGES

1. The energy is free - no fuel needed, no waste
   produced
2. Not expensive to operate and maintain
3. Can produce a great deal of energy.

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8. DISADVANTAGES

• Depends on the waves - sometimes you'll get loads
  of energy, sometimes nothing.
• 2. Needs a suitable site, where waves are
  consistently strong.
• 3. Some designs are noisy.
• 4. Must be able to withstand very rough
  weather.

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9. CONCLUSIONS
Wave power has a potential to play an important
part in the long-term goal of utilising renewable
energy in Scotland. The deployment of the LIMPET
500 has brought recognition to the technology
available in Scotland. This interest will
stimulate the growth of the industry allowing
other technologies to advance and realise their
potential. Until they become economically viable
and more competitive with other renewables such
as wind, it is more likely that wave powered
generation will supply islands or small
communities within Scotland.
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PROJECT MADE BY
Lazea Andreea
Calina Oana
Câlnicean Silviana
COORDINATED BY Schnabel Dieter
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DURING THE PROJECT...
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THE END