4. NON RENEWABLE ENERGY RESOURCES
4.1. COAL
Origin:
coal is a combustible black or brownish-black sedimentary rock
composed mostly of carbon and hydrocarbons.
Coal is a non renewable energy source
because it takes millions of years to create. The energy in
coal comes from the energy stored by plants that lived
hundreds of millions of years ago, when the earth was partly
covered with swampy forests. For millions of years, a layer of
dead plants at the bottom of the swamps was covered by layers
of water and dirt, trapping the energy of the dead plants. The
heat and pressure from the top layers helped the plant remains
turn into what we today call coal.
Extraction:
coal miners use giant machines to remove coal from the ground.
They use two methods: surface or underground mining.
Surface mining
Underground mining
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