1 The origins of coal
There are many environmental reasons why coal is a rather undesirable source of energy. Burning it introduces large amounts of gases into the atmosphere that harm the environment in a variety of ways, as well as other, solid waste products. Coal extraction leads to spoil heaps and mines that scar the landscape, land subsidence that affects roads and buildings, and in some cases water pollution.
With apparently so little going for it, why do we rely so much on coal to meet our energy needs? In this course, it will become apparent that the most appealing quality of coal is that there is plenty of it. Coal is twice as important globally as any other fuel in generating electricity, and could remain so for the next 200 years. That is reassuring for a future where energy demands continue to increase and when the alternatives to coal are currently looking less dependable. The downside is that continued burning of coal could have dire consequences for the environment in the coming centuries, unless 'cleaner' ways can be found to harness energy from it.
Before these issues are explored in more detail, it is necessary to explore the basics: what coal is, how and where it is found, and how it is extracted at a variety of depths below the surface. Another important theme concerns the distribution of coal reserves and resources, and the control exerted on them by both economics and politics.