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INTRODUCTION.
• Energy means ability to do work.
TYPES OF ENERGY.
• There are two types energy. Potential energy
• And kinetic energy. Energy can be converted
• From one form to another. But once fuels are
used, it is not possible to get back fuels from
the forms of energy. We get most of the
energy required by us from fuels and
electricity. Solar energy is also available to us
in the form of a variety of fuels. Coal
petroleum and natural gas are fuels. In this
chapter we shall learn about different sources
of energy types of fuels and why we should
use them judiciously.
SOURCES OF ENERGYRENEWABLE AND NON
RENEWABLE.
• The energy of flowing water, wind. Tides and biogas are
examples of some sources of energy that come directly or
indirectly from the sun. The sources of energy derived from solar
energy are available to us as long as we continue to receive light
and heat from the sun. These are known as renewable
sources. Non renewable sources have formed through a series of
processes that have taken place over millions of years. Once
these fuels are used will not be available again.
TYPES OF FUELS.
• Fuels are of three types solid, liquid and gases.
• SOLID FUELS
• Commonly used solid fuels in our country are fire
wood, charcoal, cow-dung cakes, agricultural
wastes and coal,
• Traditional chulas used do not completely burn
fire wood, cow-dung cakes and other agricultural
wastes.
• Coal is another important solid fuel used in
cities, industries and power stations. Coal
contains mainly carbon and is used to heat
water in industries.
Calorific value of some solid fuels.
•
•
•
•
•
FUEL
CALORIFIC VALUE OF
SOME SOLID FUELS.
Cowdung cake
6000-8000
Wood
17000-22000
Coal
25000-33000
liquid
are obtained from petroleum, also
called crude oil.Petroleum means
oil from rocks.Petroleum is also
called a fossil fuel.Different
constituents,such as
petrol,diesel,kerosene and
petroleum gas.
Calorific value of some liquid fuels.
• FUEL
•
kgram.
• Petrol
• Kerosene
• Ethenol
CALORIFIC VALUE Kjoule
per
47000
45000
30000
GASEOUS FUELS.
• Petroleum gas and natural gas are two common
gaseous fuels. Petroleum mainly consists of a
gas called butane. It also contains ethane and
propane. All these gases are hydrocarbons.
Butane is easily liquefied.
• Therefore it is supplied in liquid form in
cylinders.Natural gas is another fossil fuel that
is found with petroleum in oil.Methane is also a
hydrocarbon.Another gaseous fuel is
• biogas.
RENEWABLE SOURCES
• Sun is the most important source of energy.
At any point of time, one part or the other of
the earth’s surface is illuminated by sunlight.
So we can say that the earth receives the
energy from the sun in the form of heat and
light throughout the year, twenty- four hour a
day.
• Absorption of heat by the land and water on
the surface of the earth gives rise to many
natural phenomena, like blowing of wind, rain
and snow.
Solar cell convert solar energy into electricity .They are
usually made of silicon . Solar cells are used to generate electricity in
satellites and in far off areas such as ladakh . On a limited scale, these
are also used in calculators , traffic lights and for the transmission of
radio and television programmes from remote areas. At present , the
cost of solar cells is high and this prohibits their widespread use.
Wind energy - winds are convection currents in the air cause
by the uneven heating of the earths surface by the sun . The wind
direction and its speed keeps on changing throughout the ear at every
place on the earth.The speed of wind usually increases with height.
Wind speed is also greater over the sea and in costal areas. The
wind
energy has been used for running windmills for many centuries in
some countries,especially in Europe.The energy output from all wind
mills are coupled together to get electricity on a commercial scale.
HYDROELECTRIC ENERGY
• Nowadays, the energy of flowing water is used
for generating electricity in hydroelectric power
plants
Biogas
• In the absence of air, the plant and animal
material in the presence of water decompose to
give methane, carbon dioxide and some other
gases. This mixture of gases is know as biogas.
Biogas is a good fuel for cooking.
NUCLEAR ENERGY
• When the nucleus of a heavy atom (for example,
uranium) splits into lighter nuclei, large quantities of
energy is released. This process is called nuclear
fission and the energy produced is known as nuclear
energy or atomic energy. Another kind of nuclear
reaction is called nuclear fusion. In nuclear fusion, In
nuclear fusion, light nuclei fuse to form a larger nucleus.
Prepared By:
Sanjukta Acharya
Asst. Teacher
Hindol High School, Hindol
THANK
YOU.