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The estimated coal reserves are said to ...

The estimated coal reserves are said to be enough to last us for another two hundred years. Do you think we need to worry about coal getting depleted in this case ? Why or why not?

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Coal is used in large amount in thermal power stations for to generate electricity. The use of coal generates pollutants as the coal burns. Coal is also non-renewable resource, once depleted, it cannot be restored back. It will last only for 200 years, but formation of coal has taken millions of years and therefore we should use it with great care.
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