17-4 Coal

What Is Coal, and How Is It Extracted? A Mostly Carbon Fuel

Coal is mostly carbon and contains small amounts of sulphur, released into the atmosphere as SO2 when coal is burned. Burning coal also releases trace amounts of toxic mercury and radioactive materials.

• Area strip mining is used to extract coal found close to the Earth’s surface on flat terrain

• Contour strip mining is used on hilly or mountainous terrain.

How Is Coal Used, and How Long Will Supplies Last?

Coal is burned to generate 40% of the world’s electricity and make three-fourths of its steel. Coal is by far the world’s most abundant fossil fuel, with deposits containing 10 times more energy than oil and natural gas resources combined.

Canada has only 1% of the world’s proven reserves of coal. However, with only 0.5% of the world’s population, Canada can still export 14% of its annual coal production to the United States. The United States has one-fourth of the world’s proven coal reserves. Russia has 19% and China 14%.

What Are the Advantages and Disadvantages of Converting Solid Coal into Gaseous and Liquid Fuels? Better for the Air, Worse for the Climate

Solid coal can be converted into synthetic natural gas (SNG) by coal gasification or into a liquid fuel such as methanol or synthetic gasoline by coal liquefaction.

Without huge government subsidies, most analysts expect these synthetic fuels to play only a minor role as energy resources in the next 20–50 years. Compared with burning conventional coals, they require mining 50% more coal and their production and burning add 50% more carbon dioxide to the atmosphere. Also, they cost more to produce.