WAVE ENERGY

GROUP MEMBERS

WANNURZANA TAN NYUK MAYNOOR SUHADA BINTI AB RAZAK

SITI NUR BAIZURA BINTI ABU BAKAR NOR KHAZILAH BINTI KARIM

NOR AFIDATUL ASNI BINTI SEMSUDINSALMAH BINTI MAHFULNORDIANA BINTI YUSOF

NUR SYAHIDA ASHIKIN BINTI NOR IZLANINFARADILLA BINTI MOD YATIM

Contents

IntroductionApplications and TechnologiesConnection and operation of wave

technologiesAdvantages and Disadvantages Future PotentialConclusion

Introduction

Waves are caused by the wind blowing over the surface of the ocean. In many areas of the world, the wind blows with enough consistency and force to provide continuous waves.

Wave power refers to the use of the ocean’s waves to generate electricity.

It is the transport of energy by ocean surface waves, and the capture of that energy to do useful work — for example for electricity generation, water desalination, or the pumping of water (into reservoirs).

The world's first commercial wave farm was based in Portugal, at the Agucadoura Wave Park, 23 September 2008.  Pelamis P-750 machines generating 2.25 MW.

Wave farm in Scotland (UK)was announced on February 20, 2007 by the Scottish Executive.

Wave power varies depending on location; more powerful waves are a result of stronger winds blowing over the water’s surface. Globally, this occurs primarily in the areas between 30° and 60° latitude, both north and south.

In general, larger waves are more powerful but wave power is also determined by wave speed, wavelength, and water density.

Wave is one of the power from the ocean energy. Another type of ocean energy is tidal power.

Tidal power is a form of hydropower that converts the energy of tides into electricity or other useful forms of power.

Categories of tidal power:a) Tidal streams system(kinetic energy)b) Barrages(potential energy)

c) Dynamic tidal power-exploits a combination of potential and kinetic energy.

Application and Technologies

Wave technologies have been designed to be installed in nearshore, onshore, offshore, and far offshore locations.

A variety of technologies have been proposed to capture the energy from waves.

Some of the technologies are terminators, attenuators, point absorbers, and overtopping devices.

Nearshore

Nearshore waves offer much better prospects for wave energy development.

Nearshore waves 500 m to 2 km from the coast have 80-90% of the power potential of offshore waves.

OWC -OSCILLATING WATER COLUMN

Near Shore and On Shore

Offshore and Far Offshore

Offshore systems are situated in deep water, typically of more than 40 meters (131 feet).

Terminators

Terminator devices extend perpendicular to the direction of wave travel and capture or reflect the power of the wave.

These devices are typically installed onshore or nearshore; however, floating versions have been designed for offshore applications.

Attenuator

Attenuators are long multisegment floating structures oriented parallel to the direction of the waves.

The differing heights of waves along the length of the device causes flexing where the segments connect, and this flexing is connected to hydraulic pumps or other converters.

PELAMIS WAVE ENERGY CONVERTER

Point Absorbers

Point absorbers have a small horizontal dimension compared with the vertical dimension and utilize the rise and fall of the wave height at a single point for WEC (Wave Energy Converter).

Two types of point absorbers: PowerBuoy AquaBuoy

POWERBUOY POINT ABSORBER WAVE ENERGY CONVERTER

AQUABUOY POINT ABSORBER WAVE ENERGY CONVERTER

Overtopping Devices

Overtopping devices have reservoirs that are filled by impinging waves to levels above the average surrounding ocean.

The released reservoir water is used to drive hydro turbines or other conversion devices. Overtopping devices have been designed and tested for both onshore and floating offshore applications.

Wave Dragon Overtopping Device

Connection of wave energy

Pelamis Wave Energy Converter

A technology that uses the motion of ocean surface waves to create electricity.

The machine is made up of connected sections which flex and bend as waves pass.

How does it work ?

The wave-induced motion of these joints is resisted by hydraulic rams, which pump high pressure fluid through hydraulic motors via smoothing accumulators.

The hydraulic motors drive electrical generators to produce electricity.

Power from all the joints is fed down a single umbilical cable to a junction on the sea bed.

Several devices can be connected together and linked to shore through a single seabed cable.

Advantages and

Disadvantages

Advantages

The energy is free - no fuel needed, no waste produced.

Not expensive to operate and maintain.

Can produce a great deal of energy.

Clean and environment concerns.

Can also serve a secondary function as breakwaters.

Could be built along virtually any seacoast.

Could provide artificial habitats for marine life.

Endlessly renewable.

Disadvantages

Depends on the waves - sometimes you'll get loads of energy, sometimes almost nothing.

Needs a suitable site, where waves are consistently strong.

Some designs are noisy. But then again, so are waves, so any noise is unlikely to be a problem.

Must be able to withstand very rough weather.

Many of the technologies are new and untried, making it difficult to find funding to build the plants.

Could cause navigational hazards for the shipping and fishing industries.

Because of the open location by the open ocean, these power stations could sustain severe damage from storms affecting the coastline, such as hurricanes.

High cost is needed to build the station.

Future Potential

Some experts say that if existing technologies were widely adopted, wave power could provide 16 percent of the world’s electricity needs.

Conclusion There's a lot of energy in waves on the sea. The

hard part is getting it. Waves can make something bob up and down,

and that can drive a generator. A wave power station needs to be able to stand

really rough weather, and yet still be able to generate power from small waves.

Renewable - the waves will keep on coming whether we use them or not.

Needs to be built where there are plenty of reliable, strong waves.

The problem is that it's not easy to harness this energy and convert it into electricity in large amounts. Thus, wave power stations are rare.

REFERENCES

http://ocsenergy.anl.gov/documents/docs/OCS_EIS_WhitePaper_Wave.pdf

http://www.darvill.clara.net/altenerg/wave.htm

http://ocsenergy.anl.gov/guide/wave/index.cfm