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Earth for our Children

Energy is the ability to do work. It can take a variety of forms:
mechanical, electrical, chemical, and nuclear. To produce any type of
energy, the resources of the earth are used. The main resources of the
earth are fossil fuels such as natural gas, oil, and coal.
We get most of our energy from these fossil fuels, but this is harmful to
the environment. Fossil fuels are nonrenewable and cannot be replaced
easily. Once we use them up, they’re gone forever. They are not clean
as they pollute water or air.
In recent years, scientists try to use other types of energy resources.
They call them clean energy resources because they do not pollute the
earth. Clean energy is renewable. It is made from resources that can be
replaced, like wind, water, sunshine, tides, and plants. When renewable
energy resources are used, the demand for fossil fuels is reduced.
The most common type of clean energy is the solar power. Solar
energy is produced by the radiation that reaches the earth. People
have used the sun as a heat source for thousands of years. Iranians, for
instance, use special designs and arrangements of windows, balconies
and yards to get the most sunshine. Different types of materials might
also be used in building the houses. This keeps people warm during
cold seasons and cool during hot days of the year.
Nowadays, solar energy can be converted into other forms of energy,
such as heat and electricity. Solar energy might be used
for heating water and air in homes,

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