re newable energy

8/8/2019 Re Newable Energy

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RERE--NEWABLE ENERGYNEWABLE ENERGY

Renewable energy

sources

tidal power

wind power

Solar power

biomass and

geothermal


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THE NEED FOR RETHE NEED FOR RE--NEWABLENEWABLE

ENERGYENERGY

In the past century, the consumption ofnon-renewable sources of energy hascaused more environmental damage.

This has in turn led to many problems,such as ozone depletion and globalwarming.

Therefore, alternative sources of energyhave become very important and relevantto todays world.


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Observations of Climate Change

y The sources for 90% of the electric energy generated

today are non-renewable: the burning of coal, oil, and

natural gas.

More of the rainfall is occurring in downpours

Corals are bleaching

Glaciers are retreating

Sea ice is shrinking

Sea level is rising

Wildfires are increasing

Storm & flood dama es are much lar er


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TIDAL POWERTIDAL POWER

Three ways of using tidal power in ocean

*TIDAL ENERGY

*WAVE ENERGY

*OCEAN THERMAL ENERGY


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TIDAL ENERGYTIDAL ENERGY

Tides Governed by EarthTides Governed by Earth--MoonMoon--SunSunTidal changes in sea leveloccur as Earth rotatesbeneath bulges in oceanenvelope, which areproduced by solar and

lunar gravitational forces.

MOONS ORBIT

North Pole

Earth rotates counter-clockwise

Greatest range occurswhen sun and moon

pull in same direction

(spring tide)

Weakest when

sun andmoon in

opposition

(neap tide)


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Turning Tides into Usable EnergyTurning Tides into Usable Energy

A dam (barrage) is built

across the mouth of an

estuary.

Sluice gates allow

incoming tides to fill the

basin.

As the tide ebbs, the

water is forced through

a turbine system to

generate electricity.


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TIDAL ENERGYTIDAL ENERGY

THERE ARE TWO TYPES OF TIDES:

HIGHTIDE : THE LEVEL OF THE WATER IN THESEA WILL BE HIGH WHENCOMPARED TO THE TIDAL BASIN.

LOW TIDE : THE LEVEL OF THE WATER IN THESEA WILL BE LOW WHENCOMPARED TO THE TIDAL BASIN.


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How it worksHow it works

HIGHTIDE

LOW TIDE


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WAVE ENERGYWAVE ENERGY

Waves are caused by anumber of forces, i.e.wind, gravitational pullfrom the sun and moon,

changes in atmosphericpressure, earthquakesetc. Waves created bywind are the mostcommon waves. Unequal

heating of the Earthssurface generates wind,and wind blowing overwater generates waves.


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Waves Generated by Wind Over WaterWaves Generated by Wind Over Water

Wave

generatingarea

Waves are aconcentrated form

of solar energy.

Temperature and

pressure

differences give

rise to wind.

Wind blowing over

water generates

waves.


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HOW IT WORKSHOW IT WORKS There are several methods of

getting energy from waves. At awave 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 thechamber. We place a turbine in

this hole, which is turned by the

air rushing in and out.

The turbine turns a generator. A problem with this design is that

the rushing air can be very noisy,

unless a silencer is fitted to the

turbine.


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OTECOTEC

(Ocean Thermal Energy(Ocean Thermal Energy

Conversion)Conversion)

In 1881, Jacques Arsene d'Arsonval, aFrench physicist, was the first to proposetapping the thermal energy of the ocean.

But it was Jacques's student, GeorgesClaude, who in 1930 actually built the first

OTEC plant in Cuba. The systemproduced 22 kilowatts of electricity with alow-pressure turbine.


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OTECOTEC

The energy from the sunheats the surface water ofthe ocean. This energy is

used to produce electricity. On an average, the 60

million sq km of tropicalseas absorb solar

radiation equal to the heatcontent of 245 billionbarrels of oil.


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WORKING OF OTECWORKING OF OTEC

(OCEANTH

ERMAL ENERGY(OCEANTH

ERMAL ENERGYCONVERSION)CONVERSION)


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ADVANTAGES OF TIDAL POWERADVANTAGES OF TIDAL POWER

The tides are anatural source.

Renewable.

Abundant. Pollution free (except

during construction)

Very reliable.

We can predict whentides will be in or out.


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DISADVANTAGES OF TIDALDISADVANTAGES OF TIDAL

POWERPOWER

Very expensive to build.

Only produces power for

about 10 hours of the

day. Cost of Maintenance is

Higher.

It affects the habitat of

sea birds and fish in the

water anywhere near the

site.


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WORLDS LARGESTTIDALWORLDS LARGESTTIDAL

POWER STATIONPOWER STATION

La Rance


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La RanceLa Rance The largest tidal power

station in the world is in thela Rance estuary in northernFrance.

It was built in 1966.

T

he dam's width is 760meters .

24 turbines connected togenerators that produce 240megawatts of power. This

provides enough electricityfor a city of 300,000.

In 1997,they have installedturbines that can spin onboth the incoming and

outgoing tides.


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REFERENCES:REFERENCES:

http://www.acre.murdoch.edu.au/ago/ocean/tidal.html

http://www.edugreen.teri.res.in/explore/renew/renew.htm

http://en.wikipedia.org/wiki/renewable_energy

www.oceanenergycouncil.com/index.php/tidal-energy/tidal-energy.html


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PRESENTED BY:PRESENTED BY: ARULMOZHI.S(IT Dept) &

JANARDHAN.S(CSC Dept)

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