ByK.Harish141FA06019(EEE)

CONTENTS

1)Why do we need Electrical energy?2)Energy resources.3)Power stations 4)Conventional ways of generating electricity.5)Fossil fuels & Their alternatives.6)Types of Energy Sources.7)Conclusion.

Why do we need electrical energy?• We need electrical energy to power

the appliances in our homes.

• Electrical energy powers factories in order to make things.

• Without electricity we wouldn’t have technology as we know it today.

Energy Resources• There are a number of sources of energy that we could

use to generate electricity.• The most common are called fossil fuels.

• Power stations use fossil fuels to generate electricity.•We burn fossil fuels to release heat energy.•The heat energy is used to heat water to produce steam.•The steam drives a turbine and then a generator which converts the kinetic energy of the turbine into electrical energy.

Power stationSteam Turbines

Generator

Oil – Burning oil also releases Carbon Dioxide and Sulphur Dioxide.

Gas – Burning gas releases Carbon Dioxide gas.

• Fossil fuels consist of Coal, Oil and Gas.

Conventional Ways of Generating Electricity

Coal – Burning coal releases Carbon Dioxide (a Greenhouse gas) and Sulphur Dioxide.

•Both of these gases dissolve into the clouds and create acid rain.

Alternatives to Fossil Fuel?• If both Nuclear fuel and Fossil fuels

will eventually run then it makes sense to replace them with something else.

• Also, it makes sense to replace them with something which does not pollute the Earth!

Types of energy sourcesNon Renewable • Coal• Oil• Gas• Nuclear

Renewable• Solar• Wind• Hydroelectric• Geothermal • Biomass

Non-renewable will not be replaced.

Renewable are being replaced all the time.

SOLAR ENERGY• The Sun can be described as

our ultimate source of energy.

• Energy to grow our food comes from the Sun.

(Photosynthesis converts light into plant food)

• The Sun heats the Earth.• The energy from the Sun drives the weather which gives us wind, waves and rain.

We can change sunlight to Electricity by using solar Photovoltaic cells. This electricalEnergy can then be used directly in the home or in larger scale projects as shown.

Solar Cells are quite expensive & required large area to generate a substantial amount of power, also, they do not produce a constant supply of power. e.g. at night.

Despite this, they are often the best energy sourcefor producing electricity in remote locationse.g. on a satellite or when only small amounts of electricity are needed.

WIND ENERGY Wind is another kind of

energy that makes things work. You can’t see the wind, but when it blows on a windy day you can feel it push against your body.

Some areas of the world have areas that are windy most of the year, but the amount of electricity produced always changes with the strength of the wind.

Blowing wind spins the blades on a wind turbine. The spinning blades turn a generator that makes electricity.

Some people say that ‘wind farms’ look unsightly and that they produce a lot of noise as they turn around. This could cause are a nuisance to people living nearby. This is called visual and noise pollution.

HYDROELECTRIC ENERGY

Moving or falling water can be used to do work. Years ago movingwater turned wooden wheels to grind flour. Today moving water is used to make electricity in HYDROELECTRIC POWER STATIONS.

GEOTHERMAL ENERGY

Geothermal means “earth heat” and is as old as the world itself. Deep underground the earth is very hot and this can be used to heat water.

Around 3000m below the earths surface the rock is molten. Water sometimes comes close to this rock and turns into steam. This water can reach temperatures of more than 230degrees Celsius (Remember water boils at 100 degrees)

In some areas of the world there is enough steam produced to turn a Turbine and produce Electricity.

BIOMASS Another sustainable energy

resource is plant matter which is called Biomass.

Forests and certain crops can be cultivated to provide fuel for burning.

The fuel is burnt to release heat. The heat boils water to produce steam which turns a generator. The generator converts the KE of the steam into electricity.

Conclusion

In order to protect our environment it is better to use Renewable sources to generate power.

Thanking You

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