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Hello students. Today I'd like to tell you some information about types and sources of energy. Energy is classified into two main groups: renewable and non-renewable.
The energy generated from natural sources such as the sun, wind, rain, and tides is called renewable energy. They are plentiful and can be generated again and again. They also have low carbon emissions so they are considered green and environment-friendly. Moreover, using renewable energy can reduce your electricity bills. Unfortunately, solar energy can be only used during the daytime but not during night or the rainy season. Geothermal energy also can bring toxic chemicals beneath the earth's surface to the top and can create environmental changes.
Non-renewable energy is the energy taken from other sources that are available on earth. They are limited and will run out in the future. They can't be re-generated in a short time. Fossil fuels - natural gas, oil and coal - are examples of them. They are cheap and easy to use. However, when burnt, they release toxic gases in the air so they cause serious environmental changes such as global warming. And the important thing is that non-renewable sources will expire someday.