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Energy is what makes everything
happen. Your body needs energy
so that you can move, grow, and
keep warm. We also need energy
to power our cars, light our homes,
and do thousands of other jobs.
What is energy?
Is energy destroyed when we use it?
Science and technology
Geothermal energy
is heat from deep
underground.
Plants
can be burnt to
provide energy for cooking,
heating, and lighting.
Waves
can be used to
make small amounts
of electricity.
Wind
drives wind turbines,
which convert movement
energy into electricity.
Sources of energy
Energy comes from lots
of different sources.
Dams
harness the energy
in rivers flowing downhill
to make electricity.
Fossil fuels
such as oil are
used to power cars and to
make electricity.
Sunshine
We get nearly all our energy from
the Sun. Plants absorb the energy in
sunlight and store it as chemical energy.
The stored energy enters our bodies as
food and is released inside our body’s
cells. All animals and plants obtain
their energy from the Sun this way.
Stored energy
An object can store energy
and release it later. When
you wind up a clockwork
toy, energy is stored in
a spring. A bow and
arrow uses stored
energy to shoot the
arrow. Stored energy
is also called potential
energy because it has
the potential to make
things happen.
A bow stores energy by
bending. When you let
go, the bow springs back
into shape and releases
the stored energy.
The Sun’s
energy can be
captured by solar panels
to make electricity.
Only a tiny fraction
of the Sun’s energy
reaches Earth.
