The non-renewable energy. The Fossil fuels.
It is a sedimentary rock, but the
harder forms, such as anthracite coal, can be regarded as metamorphic rocks because of later exposure to elevated temperature and pressure. It is composed primarily of carbon along with assorted other elements, including sulfur. It is the largest single source of fuel for the generation of electricity world-wide, as well as the largest world-wide source of carbon dioxide emissions, slightly ahead of petroleum and about double that of natural gas. Coal is extracted from the ground by coal mining, either underground mining or open pit mining (surface mining).
Reserve: Coal is more evenly spread over the Earth’s surface than oil. The principal countries possessing coal reserves are the following (2003 figures):
Reserves of coal (carbon coal + lignite) in 2003, in billions of tonnes.
This chart shows how large coal reserves often exist in regions which have small reserves of oil and gas, thereby offering an alternative to these and reducing the risk of resource wars. For example, the Middle East has two thirds of the world's oil but only 5% of the coal. Asia Pacific, North America and Europe all have little oil and gas but large supplies of coal. Unfortunately, some areas such as Africa and South America lose out on all three resources.