oceanic energy(arvind sharma)

8/6/2019 Oceanic Energy(Arvind Sharma)

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Oceanic Energy

Presented by:-

Arvind Sharma

E073065



OCEAN WAVE ENERGY

The content of this topic are mainly related to the basic

study of ocean and its wave ,the ways to harness

energy, the new technologies to convert this energy into

electrical energy, its cost effectiveness, its effect on

environment and the future market conditions for this

energy. The hopes of tomorrow¶s world are mainly

concentrated on ocean wave energy(O.W.E.)

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GENERATION OF OCEAN

WAVESWind is caused by differences in temperature due to the solar heating

of the earth's atmosphere. When this wind skims over the sea, an

interaction is caused in which energy is exchanged between the wind

and the sea surface. At first, little ripples arise on the surface. Then, the

wind that skims along these ripples causes higher air pressure at the

front of the wave than at the back. As a result the ripples change into

small waves. As this process continues, the waves become higher and

the distance between the tops (wave length) becomes longer. The

amount of converted energy depends on the wind speed, the time thewind blows over the waves, and the distance it covers. This is how the

wave energy is produced .

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TYPES OF OCEAN ENERGY

Ocean energy mainly consists of the following 3 types;

1] Tidal power:-due to high and low tides over a day.

2] Ocean current:-they are due to temperature gradient

in the different part of sea.

3] Surface waves;-These are the waves due to wind over the surface of a sea.

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MEDIUMS FOR GENERATION

Generating technologies for deriving electrical power from:-

1. Ocean current energy

2. Ocean thermal energy conversion (OTEC)

3. Salinity gradient energy

4. Tidal power

5. Wave power

6. Wind power (offshore).

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METHODS TO HARNESS OCEAN

ENERGY There are three basic ways to tap the ocean for its

Energy:-

we can use the ocean's waves,

we can use the ocean's high and low tides, or

we can use temperature differences in the

water

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ACTION OF WAVES

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ACTION OF WIND ON WAVES

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METHOD TO HARNESS OCEAN

ENERGY

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OFFSHORE SYSTEM

Offshore systems are situated in deep water, typically

of more than 40 meters (131 feet). Sophisticated

mechanisms²like the Salter Duck²use the bobbing

motion of the waves to power a pump that createselectricity.

Specially built seagoing vessels can also capture the

energy of offshore waves. These floating platforms

create electricity by funneling waves through internal

turbines and then back into the sea.

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ONSHORE SYSTEM

The oscillating water column consists of a

partially submerged concrete or steel

structure that has an opening to the sea

below the waterline. As waves enter the air

column, they cause the water column to rise

and fall. This alternately compresses and

depressurizes the air column. As the waveretreats, the air is drawn back through the

turbine as a result of the reduced air pressure

on the ocean side of the turbine.

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ELECTRICITY FROM TIDAL ENERGY

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ELECTRICITY FROM OCEAN THER M AL

ENERGY CONVERSION (OTEC):

The energy from the sun heats the surface water

of the ocean. In tropical regions, the surface

water can be 40 or more degrees warmer than

the deep water. This temperature difference canbe used to produce electricity. The OTEC

system must have a temperature difference of at

least 25 degrees Celsius to operate, limiting use

to tropical regions. Hawaii has experimentedwith OTEC since the 1970¶s. There is no large-

scale operation of OTEC today

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Wave Energy Converter



SUMMARY AND CONCLUSION

OES could become a major contributor to

electricity generation, particularly in remote

regions with poor grid cover.

OES could make a major contribution to thereduction of greenhouse gas emissions, but

sustainable energy production will only be viable

if the energy production costs can be reduced to

or below the costs of energy from conventional

sources. R&D will play a key role in achieving

this.

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Challenges

Efficiently converting wave motion into

electricity; wave power is available in low-speed,

high forces, and the motion of forces is not in a

single direction. Constructing devices that can survive storm

damage and saltwater corrosion;.

High total cost of electricity; wave power will only

be competitive when the total cost of generation

is reduced

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Global Primary Energy Sources



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Renewable Energy Use



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Turbines for Wave Energy

http://www.jamstec.go.jp/jamstec/MTD/Whale/

Turbine used in Mighty Whale



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Wave Energy Power Distribution



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Wave Energy Environmental Impact

Little chemical pollution

Some hazard to shipping

No problem for migrating fish, marine life

Release little CO2, SO2, and NOx

11g, 0.03g, and 0.05g / kWh respectively

Boyle, Renewable Energy, Oxford University Press (2004)



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.

Disadvantages

depends on the waves - sometimes you'll get loads of energy,

sometimes nothing.

Needs a suitable site, where waves are consistently strong.

Some designs are noisy.

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REFERE NCES

www.wikipedia.com

www.patentstorm.com

Powerpedia.com

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oceanic energy(arvind sharma)

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