Coal is a fossil fuel that forms when dead plantmatter is converted into peat, which in turn is converted into lignite, then sub-bituminous coal, after that bituminous coal, and lastly anthracite. This process takes millions of years and occurs under the pressure of the earth'scrust.
Types of Coal
Peat: The earliest stage of coal formation, containing a high amount of water and less carbon than other types of coal.
Lignite: Also known as brown coal, it has a higher carbon content than peat but is still relatively low in energy content.
Sub-bituminous coal: It has a higher energy content than lignite and is used primarily for electricity generation.
Bituminous coal: This type of coal is widely used for power generation and is a major source of coke for steel production.
Anthracite: The highest rank of coal, known for its high energy content and low moisture and impurity levels. It is used primarily for heating.