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As the world has been facing many ecological problems, conservationists offer another way of protecting nature through using alternative energy sources.

Alternative or renewable energy sources are all sources of energy derived from nature. So, they can be used many times and are not going to perish anytime soon. All of them are used to convert their powers into electricity.

One of the first renewable sources of energy is sunlight. Solar energy is quite practical to use and can be utilized easily. Scientists developed solar panels and photovoltaic cells to get the amount of energy to meet the demands of humans.

Wind power is another way to get electricity. Scientists created windmills that spin at high speeds and produce viable amounts of energy. The blades of the windmill are attached to a turbine that turns the energy of movement into electricity. There are many windmill farms in some areas, where there is enough empty land and the wind is high enough to generate electricity.

Hydroelectric energy has recently become another source of electricity production. The power of rivers and oceans streams contain a lot of kinetic energy and can be converted into electricity through special generators.

Geothermal energy, which is hidden inside our planet, is released through the holes in the crust of the Earth. These vents of heated air and steam are used to generate power which is considered to be another energy source.

All these renewable energy sources have a lot of benefits and reduce people's dependence on fossil fuels and other non-renewable sources of energy. Besides, there is no doubt that all of them are cost-saving.

Renewable energy sources are

• all sources of energy.
• natural sources of energy.
• exhaustible energy source.

Solar energy

• is cheap.
• can be easily used.
• meets the demands of people.

Blades of windmills

• are parts of a turbine.
• convert kinetic energy into electricity.
• spin over their axes.

Hydropower is converted into electricity

• with the help of special machines.
• through streams and rivers.
• by using the power of movement.

Geothermal energy

• Is in the Earth's core.
• Is under our feet.
• Is generated by heated air and steam.

Alternative energy sources are beneficial because

• they cost less.
• they will never perish.
• all variants.