F1 c6 Energy

Science Form 1

Unit 6 Sources of Energy

6/5/2009 1SMKBPJ(A) yschow

THE VARIOUS FORMS AND

SOURCES OF ENERGY

6.1


6.1 The Various Forms and Sources of Energy

Chemical energy Electrical energy Potential energyKinetic energy Chemical energy Electrical energy

Light energy Sound energy Heat energy

Potential energy

Nuclear energy6/5/2009 3SMKBPJ(A) yschow

Potential energy

• Potential energy is the stored energy of

position possessed by an object.


Chemical energy

• Chemical Energy is energy stored in the bonds

of atoms and molecules. It is the energy that

holds these particles together.

• Biomass, petroleum, natural gas, and propane • Biomass, petroleum, natural gas, and propane

are examples of stored chemical energy.


Nuclear energy

• Nuclear energy is energy obtained from

the nucleus of some atoms.

Energy can be released from atoms

in two ways: nuclear fusion and in two ways: nuclear fusion and

nuclear fission.

The fuel most widely used

by nuclear plants for

nuclear fission is uranium.


Nuclear plan


Kinetic energy

• Kinetic energy is motion of objects.

• Moving water and wind are good examples of

kinetic energy.


Heat Energy • The Sun is the main source of heat energy.

• Heat energy flows from a region with a higher higher

temperature to a region with a lower lower temperature.

• When heat energy is supplied to matter, its temperature

rises.rises.

• Examples:

i. Burning fuels

ii. Sunshine

iii. Volcanic explosions and hot springs

iv. Electrical heaters

v. Substances taking part in chemical reactions


Light Energy

• Light energy enables us to see thingsto see things.

• The Sun is the main source of light energy and is also

known as as solar energy.solar energy.

• Examples:• Examples:

i. A burning candle or firewood

ii. Lightning flashes

iii. Lighted filament bulbs or fluorescent lamps

iv. The combustion of magnesium in oxygen


Sound Energy

• Sound energy is produced by vibrations and moves

in the form of waves through air.

• Sound energy can be transferred through solids,

liquids and gases but cannot travel through a

vacuum.

• Examples:

i. Audio-visual aids and musical instruments

ii. A ticking clock

iii. A ringing bell.


Mechanical Energy

• Mechanical energy is the total of kinetic energy and total of kinetic energy and

potential energy potential energy possessed by an object.

• Mechanical energy is produced by machines or bodies

changing their position.


i. a pendulum clock that oscillates

ii. the downward and upward movement of a boy's legs when

pedaling a bicycle

iii. the up and down movement of a see- saw

iv. the turning wheels of a vehicle

v. a rotating fan blade


Electrical Energy

• Electrical energy is the energy carried by electric current.

• A large amount of electrical energy can be produced by

generators and power plants.


i. A bicycle dynamo

ii. Solar cells and solar panels

iii. Generators in electric power stations

iv. Lightning

v. Batteries or dry cells

vi. Accumulators


Conservation of Energy

• Energy cannot be created

or destroyed.

• Energy can be transferred • Energy can be transferred

from one form to another.

• Energy converters change

one form of energy into

another form.6/5/2009 14SMKBPJ(A) yschow

The Various Sources of Energy

Geothermal Solar Radioactive

substancesWater

Coal

Waves

Firewood

BiomassWind

Natural gas

and

petroleum


Fossil fuels

• Include coal, petroleum, natural gas.coal, petroleum, natural gas.



How Is Petroleum Used ?


Diesel

• Diesel can only be used in a diesel engine, a

type of internal combustion engine used in

many cars, boats, trucks, trains, buses, and

farm and construction vehicles.farm and construction vehicles.


Petrol (Gasoline)

• Uses as fuel for car engines.


Liquefied petroleum (LPG)


Coal -- a fossil fuel

What is coal ?

Coal is a combustible black

or brownish-black

sedimentary rock composed

Where do we use coal ?

sedimentary rock composed

mostly of carbon and

hydrocarbons



HOW COAL IS USED

• FOR ELECTRIC POWER

. Power plants burn coal to make steam. The steam

turns turbines which generate electricity.

• FOR MAKING STEEL• FOR MAKING STEEL

Coal is baked in hot furnaces to make coke , which is

used to smelt iron ore into iron needed for making

steel.

"Coke" is a solid carbon made from coal6/5/2009 24SMKBPJ(A) yschow

Radioactive substances

• Nuclear or radioactive substances such as uranium

and plutonium are used to produce nuclear energy.

• Nuclear energy is used for

i. generating electrical energy i. generating electrical energy

ii. supplying energy for submarines and ships

iii. producing atomic or hydrogen bombs

iv. supplying energy for satellites, meteorological

stations and lighthouses


Geothermal source

• Geothermal energy is heat from within the heat from within the

earth. earth.

• We can use the steam and hot water

produced inside the earth to heat buildings or produced inside the earth to heat buildings or

generate electricity


Biomass fuels

• What is Biomass?

Biomass is organic

material made from

plants and animals.

• Methane is used as

fuel to heat water

and produce

electrical energy.


BIOMASS AS A TRANPSORTATION FUEL


Environmental Benefits (Biomass)

• No net increase in

atmospheric carbon

dioxide.

• restore and ensure soil

stability and health

along with minimizing

chemical residues and

habitat destruction.


Water (hydro)

• The kinetic energy of water can be used to

generate hydroelectric energy.

• The production and use of hydroelectric

energy does not pollute the environmentenergy does not pollute the environment

Hydroelectric Plant 6/5/2009 30SMKBPJ(A) yschow

Wind

• Wind energy is used for

i. pumping water from ponds

ii. moving sailing ships at sea

iii. turning wind turbines to generate iii. turning wind turbines to generate

electrical energy

• It is also a non-polluting

energy because it does not

produce any green house

effect gases.6/5/2009 31SMKBPJ(A) yschow

Parts of An Electric generating Windmill


Solar

• Solar Power is energy obtained by the sun in

the form of light.

• Solar energy is used for

i. heating water in homes i. heating water in homes

ii. producing electrical energy

Solar panel

Photovoltaic (PV devices) or “solar

cells” – change sunlight directly into electricity


Solar energy can be collected by using

various devices:

� Solar cells.

Used in calculators, watches and satellites.

�Solar panels.

i. Absorb heat energy from the Sun.i. Absorb heat energy from the Sun.

ii. Used to heat the water under the panel.

iii. Usually found on rooftop.

�Solar furnaces.

Generate electrical energy.


The major disadvantages of solar energy

• The amount of sunlight that arrives at the

earth's surface is not constant. . It depends on It depends on

location, time of day, time of year, and location, time of day, time of year, and

weather conditions. weather conditions. weather conditions. weather conditions.

• Because the sun doesn't deliver that much

energy to any one place at any one time, a

large surface area is required to collect the large surface area is required to collect the

energy at a useful rate. energy at a useful rate.


Wave

• Waves are caused by the wind blowing over

the surface of the ocean. Waves have

potential and kinetic energy.

• Waves can be used to generate electrical • Waves can be used to generate electrical

energy through the movements of the floats

connected to the power station.

wave energy plants


Tides

Tides are caused by

the gravitational pull pull

of the moon and sunof the moon and sun,

and the rotation of

the earth.the earth.

There are two-way

systems that generate

electricity on both the

incoming and incoming and

outgoing tidesoutgoing tides..6/5/2009 37SMKBPJ(A) yschow

Law of Conservation of Energy

• The law of conservation

of energy says that

energy is neither

created nor destroyed.

• When we use energy, it

doesn’t disappear.

• We change it from one

form of energy into

another.


Energy Efficiency

• Energy efficiency is the

amount of useful

energy you get from a

system.


RENEWABLE AND NON -

RENEWABLE ENERGY SOURCES

6.2


Nonrenewable and renewable energy

sources ?

Nonrenewable energy sources

• The sources of energy that

can be replenished after

Renewable energy sources

• The sources of energy that

cannot be replenished

• they have been used and

will never run out.

• Free and clean.

• after use.

• They are used up much

faster than they can be

replaced.


Renewable and Non-renewable Energy Sources


The need to conserve energy

• The supply of energy in the

form of fossil fuels is limited

and it will be completely used

up.

• Energy conservation is an • Energy conservation is an

important part of lessening

climate change.

• Energy conservation facilitates

the replacement of non-

renewable resources with

renewable energy.


Efficient Use of Energy

• When a certain form of energy is used to do

work, not all that energy is changed to useful

energy.

• A certain part of the energy is usually wasted • A certain part of the energy is usually wasted

as heat energy.

• The efficient use of energy is the fraction or

percentage of useful energy that does work.


Example:

• A bulb changes only 5% of the electrical

energy that is supplied to it to light energy.

95% of the electrical energy is lost as heat

energy. energy.

Buy energy

efficientproducts.Which do you use ?


Some effective ways to use energy efficiently:

1. Invest highly efficient equipment.

2. Construct buildings that use less energy.

3. Develop uses of alternative energy sources


1. Effective Insulation

2. High-Performance

Windows

3. Tight Construction and ducts

4. Efficient Heating and

Cooling equipment

5. Lighting and Appliances


THE IMPORTANCE OF CONSERVING

ENERGY SOURCES

6.3


Use and Management of Energy Sources

• Energy sources are

utilised in various fields:

a. Transport

b. Developmentb. Development

c. Telecommunication

d. Agriculture

e. Industry


• Energy sources must be conserved because

they are very important to us in our daily lives.

• Alternative sources of energy which are free,

should be used more often and more widely.


• To conserve sources of firewood, trees must

be replanted to replace those that have been

cut down.


What Can I Do to Save Energy?

Energy conservation

• Energy conservation is any

behavior that results in the

use of less energy. Turning

the lights off when you

Energy efficiency

• Energy efficiency is the use

of technology that requires

less energy to perform the

same function.the lights off when you

leave the room and

recycling aluminum cans are

both ways of conserving

energy.

same function.


How Can Recycling Save Energy?

• Recycling means to use something again.

• Newspapers can be used to make new

newspapers.

• Aluminum cans can be used to make new • Aluminum cans can be used to make new

aluminum cans.

• Glass jars can be used to make new glass jars.

• Recycling often saves energy and natural

resources through conservation.


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F1 c6 Energy