Global Coal Reserves
In a way similar to petroleum, production of coal will reach a peak, after which production will enter into a terminal decline. This will occur for several reasons - diminishing energy quality of remaining coal resources, competition from alternate sources of energy, government proscriptions on greenhouse gases and other types of pollution, and increasing coal prices as the "easy coal" is depleted.
There will be two peaks, one based on bulk quantity of coal and the other based on the amount of energy available from the coal produced. Since the highest quality coal tends to be mined first and depleted, it is anticipated that the energy peak will occur substantially before the bulk quantity peak.
Coal peaks will occur at different times in different countries. Some countries have been through both peaks, while others are still producing at increasing rates.